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Developing a highly selective and sensitive analysis strategy for lincomycin (LIN) is of great significance for environmental protection and food safety. Herein, we reported a novel electrochemiluminescence (ECL) aptasensor based on Ti 3 C 2 QDs-1T/2H MoS 2 nano-hybrid luminophore for detection of LIN. The hybridization of Ti 3 C 2 QDs and 1T/2H MoS 2 endowed nanocomposite with structural and compositional advantages for boosting the ECL performance of QDs by about three times. This enhancement could be attributed to the remarkable electrocatalytic activity and high conductivity exhibited by 1T/2H MoS 2. Secondly, the great surface area of 1T/2H MoS 2 is conducive to the high dispersion of Ti 3 C 2 QDs, and its good conductivity could promote charge transfer. On the other hand, the excellent catalytic performance of 1T/2H MoS 2 could facilitate the reduction of S 2 O 8 2− to produce more radical, which significantly enhance the ECL signal of Ti 3 C 2 QDs. Given these features, a sensor for detection of LIN was established based on specific recognition between target and aptamer. The sensor showed a good linear relationship (0.05 ng mL−1 ∼100 μg mL−1) with a detection limit as low as 0.02 ng mL−1. It is worth noting that this work has been validated in testing milk samples, exhibiting great potential application prospects in food analysis. [Display omitted] • A new ECL aptasensor for analyzing LIN was developed based on Ti 3 C 2 QDs-1T/2H MoS 2. • 1T/2H MoS 2 as a carrier and catalysis can improve the ECL performance of Ti 3 C 2 QDs. • The LIN aptasensor displayed excellent selectivity and high sensitivity. • The ECL sensor was used to detect LIN in milk samples with satisfactory results. [ABSTRACT FROM AUTHOR]

American ginseng (Panax quinquefolius L.) is an herbal medicine with polysaccharides as its important active ingredient. The purpose of this research was to identify the effects of the polysaccharides of P. quinquefolius (WQP) on rats with antibiotic-associated diarrhoea (AAD) induced by lincomycin hydrochloride. WQP was primarily composed of galacturonic acid, glucose, galactose, and arabinose. The yield, total sugar content, uronic acid content, and protein content were 6.71%, 85.2%, 31.9%, and 2.1%, respectively. WQP reduced the infiltration of inflammatory cells into the ileum and colon, reduced the IL-1β, IL-6, IL-17A, and TNF-α levels, increased the levels of IL-4 and IL-10 in colon tissues, improved the production of acetate and propionate, regulated the gut microbiota diversity and composition, improved the relative richness of Lactobacillus and Bacteroides, and reduced the relative richness of Blautia and Coprococcus. The results indicated that WQP can enhance the recovery of the intestinal structure in rats, reduce inflammatory cytokine levels, improve short-chain fatty acid (SCFA) levels, promote recovery of the gut microbiota and intestinal mucosal barrier, and alleviate antibiotic-related side effects such as diarrhoea and microbiota dysbiosis caused by lincomycin hydrochloride. We found that WQP can protect the intestinal barrier by increasing Occludin and Claudin-1 expression. In addition, WQP inhibited the MAPK inflammatory signaling pathway to improve the inflammatory status. This study provides a foundation for the treatment of natural polysaccharides to reduce antibiotic-related side effects. [ABSTRACT FROM AUTHOR]

Background: Blue Native polyacrylamide gel electrophoresis (BN PAGE) followed by denaturing PAGE is a widely used, convenient and time efficient method to separate thylakoid complexes and study their composition, abundance, and interactions. Previous analyses unravelled multiple monomeric and dimeric/oligomeric thylakoid complexes but, in certain cases, the separation of complexes was not proper. Particularly, the resolution of super- and megacomplexes, which provides important information on functional interactions, still remained challenging. Results: Using a detergent mixture of 1% (w/V) n-dodecyl-β-d-maltoside plus 1% (w/V) digitonin for solubilisation and 4.3–8% gel gradients for separation as methodological improvements in BN PAGE, several large photosystem (PS) I containing bands were detected. According to BN(/BN)/SDS PAGE and mass spectrometry analyses, these PSI bands proved to be PSI-NADH dehydrogenase-like megacomplexes more discernible in maize bundle sheath thylakoids, and PSI complexes with different light-harvesting complex (LHC) complements (PSI-LHCII, PSI-LHCII*) more abundant in mesophyll thylakoids of lincomycin treated maize. For quantitative determination of the complexes and their comparison across taxa and physiological conditions, sample volumes applicable to the gel, correct baseline determination of the densitograms, evaluation methods to resolve complexes running together, calculation of their absolute/relative amounts and distribution among their different forms are proposed. Conclusions: Here we report our experience in Blue/Clear-Native polyacrylamide gel electrophoretic separation of thylakoid complexes, their identification, quantitative determination and comparison in different samples. The applied conditions represent a powerful methodology for the analysis of thylakoid mega- and supercomplexes. [ABSTRACT FROM AUTHOR]

Environmental contamination by nanoparticles (NPs) and drugs represents one of the most debated issues of the last years. The aquatic biome and, indirectly, human health are strongly influenced by the negative effects induced by the widespread presence of pharmaceutical products in wastewater, mainly due to the massive use of antibiotics and inefficient treatment of the waters. The present study aimed to evaluate the harmful consequences due to exposure to antibiotics and NPs, alone and in combination, in the aquatic environment. By exploiting some of their peculiar characteristics, such as small size and ability to bind different types of substances, NPs can carry drugs into the body, showing potential genotoxic effects. The research was conducted on zebrafish (Danio rerio) exposed in vivo to lincomycin (100 mg/L) and titanium dioxide nanoparticles (TiO2 NPs) (10 µg/L) for 7 and 14 exposure days. The effects on zebrafish were evaluated in terms of cell viability, DNA fragmentation, and genomic template stability (GTS%) investigated using Trypan blue staining, TUNEL assay, and the random amplification of polymorphic DNA PCR (RAPD PCR) technique, respectively. Our results show that after TiO2 NPs exposure, as well as after TiO2 NPs and lincomycin co-exposure, the percentage of damaged DNA significantly increased and cell viability decreased. On the contrary, exposure to lincomycin alone caused only a GTS% reduction after 14 exposure days. Therefore, the results allow us to assert that genotoxic effect in target cells could be through a synergistic effect, also potentially mediated by the establishment of intermolecular interactions between lincomycin and TiO2 NPs. [ABSTRACT FROM AUTHOR]

Background: Enterococcus cecorum (EC) is one of the main reasons for skeletal disease in meat type chickens. Intervention strategies are still rare and focus mainly on early antibiotic treatment of the disease, although there are no data available concerning the effectivity of this procedure. The present study aimed to investigate the effectivity of early lincomycin-spectinomycin treatment during the first week of life after EC-infection. Furthermore, the impact of lincomycin-spectinomycin treatment and EC infection on the development of cecal microbiota was investigated. Methods: A total of 383 day-old broiler chicks were randomly assigned to four groups (non-infected and non-treated, non-infected and treated, EC-infected and non-treated, and EC-infected and treated). The EC-infected groups were inoculated orally with an EC suspension at the day of arrival and at study day 3. The treatment groups were treated with lincomycin-spectinomycin via the drinking water for six consecutive days, starting two hours after the first inoculation. Necropsy of 20 chickens per group was performed at study days 7, 14, 21, and 42. Bacteriological examination via culture and real-time PCR was performed to detect EC in different extraintestinal organs. Cecal samples of nine chickens per group and necropsy day were analyzed to characterize the composition of the cecal microbiota. Results: No clinical signs or pathologic lesions were found at necropsy, and EC was not detected in extraintestinal organs of the EC-infected and treated birds. Lincomycin-spectinomycin promoted the growth of the bacterial genus Escherichia/Shigella and reduced the amount of potentially beneficial Lactobacillus spp. in the ceca regardless of EC-infection. Unexpectedly, the highest abundances of the genus Enterococcus were found directly after ending antibiotic treatment in both treatment groups, suggesting the growth of resistant enterococcal species. EC was not detected among the most abundant members of the genus Enterococcus. Oral EC-infection at the first day of life did not influence the development of cecal microbiota in the present study. Conclusions: Lincomycin-spectinomycin treatment during the first week of life can prevent the EC-associated disease in broiler type chickens and has a direct impact on the development of the cecal microbiota. The low abundance of EC in the ceca of infected chickens underlines the pathogenic nature of the disease-causing EC strains. Further research on alternative prevention and intervention strategies is needed with regard to current efforts on reducing the use of antibiotics in livestock animals. [ABSTRACT FROM AUTHOR]

Background: In the past decade, Mycoplasma synoviae (M. synoviae) infection has become widely prevalent in China, has caused serious economic losses and has become one of the most important diseases in the chicken industry. Medication is a general approach for the control of M. synoviae infection, but antibiotics are sometimes ineffective in clinical practice. To investigate the sensitivity of M. synoviae to antimicrobials commonly used in the treatment of M. synoviae infection, the antibiotic susceptibility of 32 M. synoviae strains isolated from China from 2016 to 2019 were determined using the minimum inhibitory concentration (MIC) method. Results: All isolates had low MIC values for the combination of lincomycin and spectinomycin, pleuromutilin, and macrolides. However, the M. synoviae isolates displayed variance in MICs for doxycycline hydrochloride with a range of 0.25 to 8 μg/mL, and oxytetracycline hydrochloride with a range of 0.5 to 8 μg/mL. Three and one M. synoviae isolates showed intermediate MIC values to doxycycline hydrochloride and oxytetracycline hydrochloride, respectively. High MIC values for enrofloxacin were detected in all isolates with MICs ranging from 4 to 32 μg/mL. Furthermore, comparison of the parC QRDR identified a mutation at nucleotide position 254 (C254T) resulting in a Thr 85 Ile amino acid change in all M. synoviae isolates and the reference strain ATCC 25204 being resistant to enrofloxacin. Moreover, mutations at Glu 804 Gly and Thr 686 Ala of gyrA QRDR were identified in all M. synoviae isolates and ATCC 25204. The mutation in the QRDR of the parE gene resulted in amino acid changes at positions 197 (Pro to Ser) in 27/32 M. synoviae isolates. Conclusion: Three nonsynonymous mutations in gyrA and parE were first identified to be related to enrofloxacin resistance. Our results showed that M. synoviae resistance to enrofloxacin is widespread. [ABSTRACT FROM AUTHOR]

It is well-established that antibiotics stored individually at their optimal pH and in appropriate solvents are stable over time. However, limited information exists on the stability of antibiotics from multiple classes when prepared and stored as a mixture prior to multiresidue analysis by mass spectrometry. This study tested the stability of antibiotic standard mixtures from eight classes [amphenicols, tetracyclines, sulfonamides, quinolones, macrolides, β-lactams, lincosamides and miscellaneous (i.e., trimethoprim)] in relation to the water:methanol ratio, presence of sodium hydroxide base (to solubilise quinolones), storage temperature, and container type including plain and silanized glass vials. Antibiotics were analysed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry. Several antibiotics, mainly quinolones, tetracyclines and macrolides, were unstable when stored as mixtures for one week regardless of the water:methanol ratio, storage temperature (4, −20 or −80 °C) and presence/absence of sodium hydroxide. Silanization of glassware improved the storage stability of quinolones and macrolides but reduced the stability of tetracyclines and other antibiotics including florfenicol amine, penicillin G, erythromycin and sulfadiazine. Our results show that several antibiotics in water:methanol are unstable when stored as a mixture and suggest a limited advantage of using base or silanized glass vials for the preparation and storage of antibiotic standards mixed together. Freshly prepared antibiotic standard mixtures are recommended for multi-residue quantitation of antibiotics. Abbreviations AMOX: amoxicillin; AMP: ampicillin; AZ: azithromycin; CAP: chloramphenicol; CE: collision energy; CTC: chlortetracycline; CIP: ciprofloxacin; DOX: doxycycline; ENO: enoxacin; ENRO: enrofloxacin; ERYTH: erythromycin; FF: florfenicol; FFA: florfenicol amine; FLU: flumequine; HDPE: high-density polyethylene; LC-MS/MS: liquid chromatography–tandem mass spectrometry; LIN: lincomycin; MRM: multiple reaction monitoring; NOR: norfloxacin; OFL-D3: ofloxacin-D3; OXO: oxolinic acid; OTC: oxytetracycline; PEN-G: penicillin G; PEN-V: penicillin V; ROX: roxithromycin; SDM: sulfadimethoxine; SDZ: sulfadiazine; SMX: sulfamethoxazole; SMZ-D4: sulfamethazine-D4; SSZ: sulfasalazine; TC: tetracycline; TAP: thiamphenicol; TILM: tilmicosin; TRIM: trimethoprim; TL: tolerance limit; VIRG: virginiamycin; UPLC-MS/MS: ultra-high pressure liquid chromatography–tandem mass spectrometry. [ABSTRACT FROM AUTHOR]

Purpose: The current study aimed to optimize the culture and production parameters of industrial production of lincomycin A by Streptomyces lincolnensis using a statistical approach that could also reduce unwanted by-products. Methods: The Plackett-Burman design, steepest ascent method, and response surface design were used to evaluate different factors that affect lincomycin A production. Results: Using an optimized S. lincolnensis fermentation medium, lincomycin A production was increased up to 4600 mg/L in shaking flasks, which indicated a 28.3% improvement over previous production in an un-optimized medium (3585 mg/L). Additionally, the concentration of lincomycin B by-product was reduced to 0.8%, which was 82.2% lower than that in the un-optimized medium. Further, quantitative real-time PCR analysis revealed the optimized medium improved lincomycin A production by stimulating key genes in the lincomycin A biosynthesis pathway, as well as an osmotic stress gene. Conclusions: Based on the results, the sequential optimization strategy in this study provides powerful means for the enhancement of lincomycin A with less by-product. We found that osmotic stress reduced the concentration of lincomycin B, which could also help reduce fermentation by-product yields in other actinobacteria. [ABSTRACT FROM AUTHOR]

Wildlife plays a critical role as a reservoir for zoonosis especially pathogenic enteric bacteria. In this study we evaluated the presence of E. coli and Salmonella isolates from wild birds and determined their antimicrobial resistance. Intestine and fecal samples from 82 dead wild birds obtained from rehabilitation centre, were examined by microbiological analysis, antibiotic susceptibilities against of 18 antimicrobials and presence of tetracycline resistance genes by multiplex and singleplex PCR were investigated. A total of 51 E. coli were identified as well as Salmonella Kentucky and Salmonella Bisberg. A majority of the E. coli isolates were resistant to lincomysin (100%), penicilline (96.1%), kanamycin (80.4%), tetracycline (68.6%), and oxytetracycline (64.7%). All Salmonella serotypes were resistant to lincomycin, nalidixic acid and penicilline.In addition, 58.82% of E. coli isolates had phenotypic resistance to at least three or more antimicrobials. Our results indicated that the high frequency of tetracycline resistance (68.62%) due to the tet (A), tet (B), and tet (D) genes. This is the first report isolating S. Bisberg and determining antibiotic susceptibility of E.coli and Salmonella isolates from wild birds in Turkey. These results will help providing better understand of the dissemination of antibiotic resistancy in the environment, which can be used to potentially decrease spread through bird migration. Moreover, these results help assess the risk of spread of resistance from wild birds to humans. [ABSTRACT FROM AUTHOR]

The objective of the present experiment was to evaluate the effect of bioactive peptides derived from cottonseed (BPC) on chicken performance, immunity, the total antioxidant activity of serum and intestinal morphology. A total of 280 one-day-old male broiler chicks (Ross 308) were randomly allocated into 1 of the following 7 experimental treatments (5 replicates per treatment with 8 broilers per pen). Five diets were formulated to contain 0 (control), 3, 4, 5 and 6 g BPC/kg of diet in comparison with control + 50 U excessive dietary vitamin E and control + 2 mg lincomycin. At 40 d the BW tended to improve in broilers supplemented with an antibiotic, 3, 5 and 6 g BPC/kg groups (p > .05). In the whole trial, supplementing 5 g BPC/kg increased feed intake of broilers in comparison to other groups (p

This article is the Russian translation of the Plain Language Summary (PLS) of the Cochrane Review previously published in the Cochrane Database of Systematic Reviews. Original publication: Popp M, Stegemann M, Riemer M, Metzendorf MI, Romero CS, Mikolajewska A, et al. Antibiotics for the treatment of COVID-19. Cochrane Database of Systematic Reviews. Version published: 22 October 2021. https://doi.org/10.1002/14651858.CD015025

The use of systemic antibiotics may influence the oral microbiota composition. Our aim was to investigate in this retrospective study whether the use of prescribed antibiotics associate with periodontal status, oral microbiota, and antibodies against the periodontal pathogens. The Social Insurance Institution of Finland Data provided the data on the use of systemic antibiotics by record linkage to purchased medications and entitled reimbursements up to 1 year before the oral examination and sampling. Six different classes of antibiotics were considered. The Parogene cohort included 505 subjects undergoing coronary angiography with the mean (SD) age of 63.4 (9.2) years and 65% of males. Subgingival plaque samples were analysed using the checkerboard DNA-DNA hybridisation. Serum and saliva antibody levels to periodontal pathogens were analysed with immunoassays and lipopolysaccharide (LPS) activity with the LAL assay. Systemic antibiotics were prescribed for 261 (51.7%) patients during the preceding year. The mean number of prescriptions among them was 2.13 (range 1–12), and 29.4% of the prescriptions were cephalosporins, 25.7% penicillins, 14.3% quinolones, 12.7% macrolides or lincomycin, 12.0% tetracycline, and 5.8% trimethoprim or sulphonamides. In linear regression models adjusted for age, sex, current smoking, and diabetes, number of antibiotic courses associated significantly with low periodontal inflammation burden index (PIBI, p < 0.001), bleeding on probing (BOP, p = 0.006), and alveolar bone loss (ABL, p = 0.042). Cephalosporins associated with all the parameters. The phyla mainly affected by the antibiotics were Bacteroidetes and Spirochaetes. Their levels were inversely associated with the number of prescriptions (p = 0.010 and p < 0.001) and directly associated with the time since the last prescription (p = 0.019 and p < 0.001). Significant inverse associations were observed between the number of prescriptions and saliva concentrations of Prevotella intermedia , Tannerella forsythia , and Treponema denticola and subgingival bacterial amounts of Porphyromonas gingivalis , P. intermedia , T. forsythia , and T. denticola. Saliva or serum antibody levels did not present an association with the use of antibiotics. Both serum (p = 0.031) and saliva (p = 0.032) LPS activity was lower in patients having any antibiotic course less than 1 month before sampling. Systemic antibiotics have effects on periodontal inflammation and oral microbiota composition, whereas the effects on host immune responses against the periodontal biomarker species seem unchanged. [ABSTRACT FROM AUTHOR]

Microwave dielectrometry and UV/Vis spectrophotometry methods have been used to study the aqueous solutions of selected antibiotics of different classes: lincomycin hydrochloride, levofloxacin hemihydrate, amikacin sulfate, and gentamicin sulfate. The microwave dielectrometry technique demonstrates high sensitivity of complex permittivity values of antibiotics water solutions from antibiotics concentration in such solutions. In our study, the microwave dielectrometry data are validated by the UV-Vis spectrophotometry results for levofloxacin and lincomycin aqueous solutions. The Fisher's correlation coefficients for the electromagnetic waves absorbance values, obtained by the different methods, are close to unity for the mentioned antibiotics. The obtained experimental results confirm that the microwave dielectrometry method developed by us is prospective to be applied for antibiotics determination in aqueous solutions including environmental water samples. [ABSTRACT FROM AUTHOR]

Background and Objectives: One major source of antibiotic contamination in the sea is from aquaculture. We monitored the concentration of commonly used antibiotic classes and antibiotic resistance genes (tet(M), sul1, sul2 and sul3) in aquaculture farms in Peninsular Malaysia. Methods: Antibiotic residues and resistance genes were quantified using high-performance liquid chromatography and real-time PCR respectively. Risk quotients in European technical guidance document on risk assessment was used to assess the potential environmental risk. Results: We detected 23 antibiotics with tetracyclines, sulfonamides and quinolones were the most frequently detected classes, indicating a wide distribution of antibiotics in Malaysian aquaculture farms. The dendrogram and heatmap revealed three groups of antibiotic concentration patterns but with no differences in the types of antibiotics usage among aquaculture farms. The ARGs (10−3 copies/16S) were detected in >90% of the sites except for sul3. Ciprofloxacin, enrofloxacin, norfloxacin and lincomycin posed risks to cyanobacteria and algae in Kelantan, Perak and Pahang. Conclusion: Relative to Asian aquaculture farms, the residues detected here were at low or moderate levels except for quinolones. This study will be useful to develop effective management of aquaculture wastewater in order to mitigate antibiotic pollution and transmission of ARGs to humans through the food chain. [ABSTRACT FROM AUTHOR]

BACKGROUND: At present, the supervision of antibiotic abuse and its research is being strengthened. In recent years, antibiotics have been detected in varying degrees in water in central China. This reinforces the concern of the pollution of antibiotics in surface and groundwater. OBJECTIVES: To investigate the distribution characteristics of 29 antibiotics in groundwater in Harbin. METHODS: A total of 26 groups of groundwater samples were collected in Harbin, and the sampling scope included habitation and production areas such as densely populated, industrial production, agricultural districts and animal husbandry. The ultra - performance liquid chromatography - triple quadrupole mass spectrometry method was used to analyze 29 kinds of antibiotics covering six types, including sulfonamides, quinolones, macrolides, f3 - lactams, tetracyclines, and lincosamides. RESULTS: Antibiotics in the groundwater of Harbin were mainly composed of sulfonamides, quinolones, macrolides and tetracyclines and the detection rates were 61.5%, 46.2%, 42.3% and 38.5%, respectively. The content of antibiotics detected ranged from 0. 02 to 681 ng/L, and the highest contents of sulfathiazole, sulfadiazine, and lincomycin were more than 100ng/L. The average content of quinolones was low compared with some domestic and international areas (such as Beijing, Tianjin, and Barcelona). Sampling sites with higher antibiotic levels were mainly found in the central, southern and eastern regions of the city. These areas are also relatively densely populated and are generally distributed around pharmaceutical factories, urban sewage outlets, and poultry and livestock farms. CONCLUSIONS: The distribution characteristics of antibiotics in groundwater in Harbin are strongly related to the impact of human production and living activities. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that antibiotic administration causes gut injury, negatively affecting nutrient digestion, immune regulation, and colonization resistance against pathogens due to the disruption of gut microbiota. However, the time-course effects of therapeutic antibiotics on alterations of gut microbes and short-chain fatty acids (SCFAs) in young swine are still unknown. In this study, twenty piglets were assigned into two groups and fed commercial diets with or without lincomycin in the first week for a 28-day trial period. Results showed that 1-week lincomycin exposure (LE) did reduce the body weight on day 14 (p = 0.0450) and 28 (p = 0.0362). The alpha-diversity notably reduced after 1-week LE, and then gradually raised and reached the control group level in the second week on cessation of LE, indicated by the variation of Sobs, Chao, Shannon, and ACE index (p < 0.05). Beta-diversity analysis revealed that the distinct microbial cluster existed persistently for the whole trial period between two groups (p < 0.001). The relative abundance of most microbes including fiber-degrading (e.g., Agathobacter and Coprococcus), beneficial (e.g., Lactobacillus and Mitsuokella), or pathogenic bacteria (e.g., Terrisporobacter and Lachnoclostridium) decreased (LDA score > 3), and the concentration of SCFAs also diminished in the feces of 1-week lincomycin-administrated young swine, indicating that therapeutic LE killed most bacteria and reduced SCFA production with gut dysbiosis occurring. After the LE stopped, the state of gut dysbiosis gradually attenuated and formed new gut-microbe homeostasis distinct from microbial homeostasis of young pigs unexposed to lincomycin. The increased presence of potential pathogens, such as Terrisporobacter, Negativibacillus, and Escherichia-Shigella, and decreased beneficial bacteria, such as Lactobacillus and Agathobacter, were observed in new homeostasis reshaped by short-lincomycin administration (LDA score > 3 or p < 0.05), adversely affecting gut development and health of young pigs. Collectively, these results suggested that severe disruption of the commensal microbiota occurred after short-term LE or termination of LE in young swine. Key points: • Therapeutic lincomycin exposure induced gut dysbiosis, killing most bacteria and reducing short-chain fatty acid production. • Gut dysbiosis gradually attenuated and formed new homeostasis after lincomycin exposure stopped. • The new homeostasis, increased Escherichia-Shigella etc. and decreased Lactobacillus etc., was potentially harmful to gut health. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the therapeutic effects of berberine on necrotic enteritis (NE) in broilers caused by Clostridium perfringens. A total of 240 1-day-old Arbor Acres chicks were divided into four groups, as negative controls (NC), positive controls (PC), berberine- (BER-) treated, or lincomycin- (LMY-) treated groups. Broilers were challenged with C. perfringens at 15-21 days of age, followed by BER or LMY supplied in drinking water for 7 days. Experimental results showed that C. perfringens infection significantly decreased growth performance and increased intestinal necrosis index and the number of C. perfringens present to 6.45 Log10CFU/g (P < 0.001). Proinflammatory cytokines in the ileum were significantly increased, but the expression of ileal tight junction proteins occludin and claudin-1 was significantly reduced. Both BER and LMY ameliorated some of these observations. Compared with the PC group, the number of C. perfringens in the cecum was significantly decreased following treatment (P < 0.001), and growth performance and small intestine morphology were similar to those of the NC group (P > 0.05). IL-1β, IL-6, and TNF-α levels as well as occludin and claudin-1 expression were also significantly improved (P < 0.05). BER has the potential to replace antibiotics for NE caused by C. perfringens. [ABSTRACT FROM AUTHOR]

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The specific concentrations of lincomycin in non‐target feed for food‐producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. However, due to the lack of data on the parameters required to calculate the FARSC, it was not possible to conclude the assessment until further experimental data become available. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels of lincomycin in feed that showed to have an effect on growth promotion/increased yield were reported. It was recommended to carry out studies to generate the data that are required to fill the gaps which prevented the calculation of the FARSC for lincomycin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recyclable aqueous two-phase systems were constructed using EO 30 PO 70 and P ADB5.22. • Phase formation mechanism have been studied using Low-field NMR. • Lincomycin was better partitioned with partition coefficient of 5.94. • The recoveries of EO 30 PO 70 and P ADB5.22 reached 95.51 % and 96.18 %, respectively. Aqueous two-phase systems (ATPS) have been widely used in the laboratory separation and purification of antibiotics. However, its large-scale application is limited due to the difficulty in the recovery of the phase-forming polymers. In this study, we aimed to develop a thermo-pH responsive recyclable ATPS using thermo-responsive polymer EO 30 PO 70 and pH-responsive polymer P ADB5.22 for lincomycin partition. This ATPS can rapidly form two-phase interface in less than 5 min and can sustainably be reused. The phase separation mechanism was studied by low-field nuclear magnetic resonance (LF-NMR) and surface tension. The effects of polymer concentration, lincomycin content, pH, temperature and salts type and concentrations on lincomycin partition were investigated. The 25 % (w/v) EO 30 PO 70 /4.5 % (w/v) P ADB5.22 ATPS showed good partitioning at room temperature for lincomycin fermentation broth in the presence of 80 mM LiCl at pH 9.1, with a partition coefficient of 5.94 and extraction recovery of 94.68 %. In addition, the recycling of the two polymers showed a high efficiency, with 95.51 % and 96.18 % recoveries of EO 30 PO 70 and P ADB5.22 after four cycles, respectively. This recyclable ATPS has a promising industrial application in the separation and purification of antibiotics. [ABSTRACT FROM AUTHOR]

In the present study, we aimed to investigate the antibacterial activity and mechanisms of plectasin-derived peptide NZ2114 in vitro and its therapeutic effects in vivo on broilers challenged with Clostridium perfringens. In vitro assay showed that NZ2114 had potent (minimal inhibitory concentration, 0.91 μM) and rapid antibacterial activity (99.9% reduction within 2 h), and the dual antibacterial mechanisms (including interfering with the cell membrane and intracellular DNA) against C. perfringens CVCC 2030. In vivo study, NZ2114 tended to increase linearly and quadratically the average daily gain as NZ2114 level increased and was the highest at 20 mg/L. NZ2114 at 10 ~ 40 mg/L dramatically reduced jejunal lesion score. Besides, the levels of IL-6, TNF-α, and IL-1β tended to downregulate linearly and quadratically as the NZ2114 level increased and were all the lowest at the dose of 20 mg/L. NZ2114 significantly upregulated those levels of IgA, IgG, IgM, and sIgA with a linear and quadratic dose effect, with the highest IgA, IgG, IgM, and sIgA at 20 mg/L. Finally, NZ2114 tended to linearly and quadratically increase the numerical value of crypt depth, with the lowest value at 40 mg/L. Lincomycin only dramatically reduced the jejunal lesion score and increased the numerical value of crypt depth. These results indicate that NZ2114 has the potential as a new alternative to antibiotics for the treatment of C. perfringens–induced necrotic enteritis infection. Key points • NZ2114 could kill C. perfringens by dual antibacterial mechanisms • Broiler necrotic enteritis model induced by C. perfringens was established • NZ2114 treatment could ameliorate C. perfringens–induced necrotic enteritis [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the efficiency of NiO/WO3 heterostructure photocatalytic process for removal of lincomycin antibiotic from aqueous solutions. WO3, NiO, and NiO/WO3 particles were synthesized and characterized by several techniques. NiO and WO3 photocatalytic properties in removal of lincomycin antibiotic were evaluated from experimental and theoretical perspectives. The influence of various parameters such as type of irradiation and photocatalyst, initial concentration of lincomycin (mg/L), NiO loading percentage (wt %), mass of NiO/WO3 (g), time (h), and pH were investigated. According to the results, the interaction energy for lincomycin adsorbed on NiO surface was –114.717 kJ mol–1 and for adsorbed on WO3 surface was –28.379 kJ mol–1. It is apparent from these interaction energy values that lincomycin adsorbed on WO3 surface has more negative Eint values and stronger interactions as compared to NiO surface. According to the experimental and theoretical results, loading of NiO onto WO3 increased the catalyst adsorption to lincomycin and ultimately increased the removal efficiency. The results shown that pH plays an important role in the removal of lincomycin. The maximum removal efficiency of 98.56% was obtained at pH 5, 0.2 g NiO/WO3 (2 wt %), 25 mg/L initial lincomycin concentration and 2 h exposure under sunlight. [ABSTRACT FROM AUTHOR]

The lincosamide family antibiotic lincomycin is a widely used antibacterial pharmaceutical generated by Streptomyces lincolnensis, and the high-yield strain B48 produces 2.5 g/L lincomycin, approximately 30-fold as the wild-type strain NRRL 2936. Here, the genome of S. lincolnensis B48 was completely sequenced, revealing a ~10.0 Mb single chromosome with 71.03% G + C content. Based on the genomic information, lincomycin-related primary metabolism network was constructed and the secondary metabolic potential was analyzed. In order to dissect the overproduction mechanism, a comparative genomic analysis with NRRL 2936 was performed. Three large deletions (LDI-III), one large inverted duplication (LID), one long inversion and 80 small variations (including 50 single nucleotide variations, 13 insertions and 17 deletions) were found in B48 genome. Then several crucial mutants contributing to higher production phenotype were validated. Deleting of a MarR-type regulator-encoding gene slinc377 from LDI, and the whole 24.7 kb LDII in NRRL 2936 enhanced lincomycin titer by 244% and 284%, respectively. Besides, lincomycin production of NRRL 2936 was increased to 7.7-fold when a 71 kb supercluster BGC33 from LDIII was eliminated. As for the duplication region, overexpression of the cluster situated genes lmbB2 and lmbU, as well as two novel transcriptional regulator-encoding genes (slinc191 and slinc348) elevated lincomycin titer by 77%, 75%, 114% and 702%, respectively. Furthermore, three negative correlation genes (slinc6156, slinc4481 and slinc6011) on lincomycin biosynthesis, participating in regulation were found out. And surprisingly, inactivation of RNase J-encoding gene slinc6156 and TPR (tetratricopeptide repeat) domain-containing protein-encoding gene slinc4481 achieved lincomycin titer equivalent to 83% and 68% of B48, respectively, to 22.4 and 18.4-fold compared to NRRL 2936. Therefore, the comparative genomics approach combined with confirmatory experiments identified that large fragment deletion, long sequence duplication, along with several mutations of genes, especially regulator genes, are crucial for lincomycin overproduction.

Introduction. Combinations of fibrous materials with therapeutic agents as a drug delivery system are currently studied. A new direction has appeared in reconstructive surgery – tissue engineering, which aims to restore biological functions, i.e. tissue regeneration, not only to replace it with synthetic material. The objective of the study was to evaluate the antibiotic-sorbing ability of the three-dimensional non-woven matrices we created for reconstructing bone defects, made of polycaprolactone, and the possibility of releasing the impregnated antibiotic from the matrix material. Materials and methods. The study was conducted in the Department of Surgical Dentistry of Ivano-Frankivsk National Medical University, Ukraine, between September 12, 2019 – October 3, 2019. We used samples of three-dimensional micro-fibrous non-woven matrix for the defects’ reconstruction of the bone tissue made of polycaprolactone according to the developed technique. Collagen fragments were used as control. Results. The evaluation of the preservation of antibiotics in samples of matrix materials was performed on the 1st, 3rd, 5th, 7th, 14th, 18th and 21st day of the experiment. The obtained experimental data indicate that both drugs (cefazolin and lincomycin) were stored in significant quantities both in the collagen and the polycaprolactone matrix, throughout the entire observation period. Lincomycin impregnated in the polymer matrix is less stable during storage than cefazolin. Antibiotics impregnated in the collagen matrix are stored slightly better than when impregnated into polycaprolactone, due to a smaller pore diameter in collagen and, accordingly, a better expressed capillary effect. Conclusions. The developed matrix materials are a mean of a one-time local delivery of the drug to tissues in the damaged zone. This is especially relevant in surgical dentistry, since even strict adherence to aseptic rules cannot ensure that individual microbial cells from the surface of the oral mucosa and saliva get into the surgery area.

Abstract Background Lincomycin, produced by Streptomyces lincolnensis, is a lincosamide antibiotic and widely used for the treatment of the infective diseases caused by Gram-positive bacteria. The mechanisms of lincomycin biosynthesis have been deeply explored in recent years. However, the regulatory effects of LmbU that is a transcriptional regulator in lincomycin biosynthetic (lmb) gene cluster have not been fully addressed. Results LmbU was used to search for homologous LmbU (LmbU-like) proteins in the genomes of actinobacteria, and the results showed that LmbU-like proteins are highly distributed regulators in the biosynthetic gene clusters (BGCs) of secondary metabolites or/and out of the BGCs in actinomycetes. The overexpression, inactivation and complementation of the lmbU gene indicated that LmbU positively controls lincomycin biosynthesis in S. lincolnensis. Comparative transcriptomic analysis further revealed that LmbU activates the 28 lmb genes at whole lmb cluster manner. Furthermore, LmbU represses the transcription of the non-lmb gene hpdA in the biosynthesis of l-tyrosine, the precursor of lincomycin. LmbU up-regulates nineteen non-lmb genes, which would be involved in multi-drug flux to self-resistance, nitrate and sugar transmembrane transport and utilization, and redox metabolisms. Conclusions LmbU is a significant pleiotropic transcriptional regulator in lincomycin biosynthesis by entirely activating the lmb cluster and regulating the non-lmb genes in Streptomyces lincolnensis. Our results first revealed the pleiotropic regulatory function of LmbU, and shed new light on the transcriptional effects of LmbU-like family proteins on antibiotic biosynthesis in actinomycetes.

Abstract The specific concentrations of lincomycin in non‐target feed for food‐producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. However, due to the lack of data on the parameters required to calculate the FARSC, it was not possible to conclude the assessment until further experimental data become available. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels of lincomycin in feed that showed to have an effect on growth promotion/increased yield were reported. It was recommended to carry out studies to generate the data that are required to fill the gaps which prevented the calculation of the FARSC for lincomycin.

Bacterial drug resistance to antibiotics is growing globally at unprecedented levels, and strategies to overcome treatment deficiencies are continuously developing. In our approach, we utilized metal nanoparticles, silver nanoparticles (AgNPs), known for their wide spread and significant anti-bacterial actions, and the high-dose regimen of lincosamide antibiotic, lincomycin, to demonstrate the efficacy of the combined delivery concept in combating the bacterial resistance. The anti-bacterial actions of the AgNPs and the lincomycin as single entities and as part of the combined mixture of the AgNPs–lincomycin showed improved anti-bacterial biological activity in the Bacillus cereus and Proteus mirabilis microorganisms in comparison to the AgNPs and lincomycin alone. The comparison of the anti-biofilm formation tendency, minimum bactericidal concentration (MBC), and minimum inhibitory concentration (MIC) suggested additive effects of the AgNPs and lincomycin combination co-delivery. The AgNPs’ MIC at 100 μg/mL and MBC at 100 μg/mL for both Bacillus cereus and Proteus mirabilis, respectively, together with the AgNPs–lincomycin mixture MIC at 100 + 12.5 μg/mL for Bacillus cereus and 50 + 12.5 μg/mL for Proteus mirabilis, confirmed the efficacy of the mixture. The growth curve test showed that the AgNPs required 90 min to kill both bacterial isolates. The freshly prepared and well-characterized AgNPs, important for the antioxidant activity levels of the AgNPs material, showed radical scavenging potential that increased with the increasing concentrations. The DPPH’s best activity concentration, 100 μg/mL, which is also the best concentration exhibiting the highest anti-bacterial zone inhibition, was chosen for evaluating the combined effects of the antibiotic, lincomycin, and the AgNPs. Plausible genotoxic effects and the roles of AgNPs were observed through decreased Bla gene expressions in the Bacillus cereus and BlaCTX-M-15 gene expressions in the Proteus mirabilis.

Background: Antibiotic residues that come from food of animal origin, such as broiler chicken, have a variety of consequences on human health and increase the likelihood of antibiotic resistance. Lincomycin residue investigations in broiler chicken especially in plasma broiler chicken should be undertaken utilizing the validation method analysis., Aim: The purpose of this study is to determine the high-performance liquid chromatography (HPLC) as a validation method for calculating the residual concentration of lincomycin in broiler chicken blood plasma and compare it with the minimum Inhibitor Concentration (MIC) and Maximum Residue Limits (MRLs) standards for lincomycin., Methods: Thirty-five-day-old broiler chickens cobb 700 were weighed and randomly allocated to and separated into control (placebo) and six treatment groups of varying doses and duration. The treatment group's suggested dosage of lincomycin was 50, 100, or 150 mg/kg/day given to 18-day-old chicken, along with drinking water for a week (A group) and 2 weeks (P group). Lincomycin levels in blood plasma were validated using HPLC. The residual lincomycin concentrations 24 hours and 1 week after injection were compared to the lincomycin MIC and the Indonesian National Standard of MRL., Result: The validation of linscomycin reveals a linear value in blood plasma with an R 2 of 0.9983. Precision and accuracy levels indicate promising results for detecting lincomycin. The retention duration for 100 µg/ml lincomycin was 10.0-10.5 minutes. Lincomycin had LOD and LOQ values of 13.98 and 4.86 µg/ml, respectively. After 1 week of dosing at 50 and 100 mg/kg dosages, lincomycin residue detection was 0.00, which was below the MRL criterion of <0.1 ppm. The study found that the residual concentration of 150 mg/kg dosages for a week and 100/150 mg/kg doses for 2 weeks above the lincomycin MIC limits against Mycoplasma synoviae, Staphylococcus aureus, and Salmonella enteritidis ., Conclusion: Lincomycin detection by HPLC in chicken blood plasma showed promising results in terms of linearity, accuracy, precision, specificity, and sensitivity. Lincomycin administration for 1 week at doses of 50 and 100 mg/kg resulted in the lowest residual concentration below the lincomycin MIC and MRL standards., Competing Interests: The authors declare that they have no conflict of interest.

Aim. Study of the antibiotic resistance of functionally active probiotic cultures of "VIVO probioyogurt" leaven to determine the possibility of using a fermented milk product, which is prepared on its basis, during antibiotic therapy to maintain and restore normal intestinal microflora. Methods. Pure cultures of lactic acid bacteria (LAB) were selected for the study: (Lactobacillus delbrueckii ssp., L. acidophilus, L.casei, L. rhamnosus, L.paracasei, Streptococcus thermophilus, Bifidobacterium lactis (2 strains), B. infantis ), which are part of leaven "VIVO probioyogurt" the quality of which is confirmed by certificates of the International Organization for Standardization ISO 9001: 2008, as well as ISO 22000: 2005. The method of the experiment consisted of the following stages: preparation of nutrient media ("Lactobacagar", "Bifidoagar", glucose-peptone medium), working solutions of antibiotics; working suspension of LAB; suspensions of cultures (lacto- and bifidobacteria), cultivation LAB on elective nutrient media with the addition of antibiotics and evaluation of research results. Determination of antibiotic resistance of LAB was performed by the method of double dilutions. Results. The use of this technique enabled to establish the minimum inhibitory concentration (MIC) of antibiotics of different groups relative to the LAB. The results of the research were processed using a licensed computer program Microsoft Excel. Conclusions. Evaluation of the results of studies to determine the MIC of antibiotics – benzylpenicillin, azithromycin, lincomycin, gentamicin sulfate, ceftriaxone, norfloxacin, amoxil, streptomycin, tetracycline, erythromycin in relation to IBD; fermented milk product, which was prepared on the basis of this starter culture, it was advisable to use during antibiotic therapy to restore and maintain normal intestinal microflora. [ABSTRACT FROM AUTHOR]

Lincomycin is an important antimicrobial agent which is widely used in clinical and animal husbandry. The biosynthetic pathway of lincomycin comes to light in the past 10 years, however, the regulatory mechanism is still unclear. In this study, a redox‐sensing regulator Rex from Streptomyces lincolnensis (Rexlin) was identified and characterized to affect cell growth and lincomycin biosynthesis. Disruption of rex resulted in an increase in cell growth, but a decrease in lincomycin production. The results of quantitative real‐time polymerase chain reaction showed that Rexlin can promote transcription of the regulatory gene lmbU and the structural genes lmbA, lmbC, lmbJ, lmbV, and lmbW. However, electrophoretic mobility shift assay analysis demonstrated that Rexlin can not bind to the promoter regions of these genes above. Findings in this study broadened our horizons in the regulatory mechanism of lincomycin production and laid a foundation for strain improvement of antibiotic producers. [ABSTRACT FROM AUTHOR]

Background: Livestock manure is an important reservoir of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs). The bacterial community structure and diversity are usually studied using high-throughput sequencing that cannot provide direct evidence for ARB changes. Thus, little is known about the distribution of ARB, especially in the presence of different antibiotics in composting process. In this study, the fate of ARB was investigated in aerobic composting of swine manure, using chlortetracycline, sulfamethoxazole, lincomycin, and ciprofloxacin as typical antibiotics. The abundance and species of ARB were analyzed systematically to evaluate their ecological risk at different stages of composting. Results: The absolute abundance of total ARB decreased, while the relative abundance increased on day 2. The relative abundance of lincomycin-resistant bacteria was higher than other ARBs during the whole composting process. The absolute abundance of four ARBs was 9.42 × 106–2.51 × 102 CFU/g (lincomycin- > chlortetracycline- > sulfamethoxazole- > ciprofloxacin- > multiple antibiotic-resistant bacteria), and they were not completely inactivated at the end of composting. Antibiotics led to a partial proliferation of ARBs including Corynebacterium, Sporosarcina, Solibacillus, and Acinetobacter. Especially, Corynebacterium, a pathogenic genus, was observed in chlortetracycline and lincomycin treatments. Conclusion: Among the antibiotics studied, lincomycin showed the highest ecological risk, due to it expanded the range of lincomycin-resistant bacteria at the phyla level (Firmicutes, Actinobacteria, and Proteobacteria). The principal co-ordinates analysis indicated that the bacterial community structure was primarily associated with the composting stages rather than antibiotic types. Possible potential hosts and the related to the decrease of ARGs abundance were indicated based on the network analysis. The decrease of culturable Proteobacteria and the increase of culturable Firmicutes (Solibacillus, Bacillus) partially explained the high degradation rate of various ARGs with the progress of composting in this study. These results provided important information for the control of antibiotic resistance in composting. [ABSTRACT FROM AUTHOR]

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ABSTRACT: Regardless of whether antimicrobial drugs are administered to laying hens legally or illegally, residues of these drugs may be present in the eggs. Even if the eggs are not intended for human consumption, byproducts/biowaste, such as eggshells, may contain residues of the drugs used, which may pose a risk to human health and the environment. In the presented research, 2 different groups of laying hens received enrofloxacin (10 mg/kg body weight) and lincomycin (20 mg/kg body weight) once daily for 5 d. Eggs were collected daily and the concentration of enrofloxacin, its metabolite ciprofloxacin, and lincomycin residue in the eggshells, whole eggs, egg yolks, and egg whites were determined by ultra-high-performance liquid chromatography-tandem mass spectrometry. This study demonstrates the transfer of enrofloxacin, ciprofloxacin, and lincomycin into the eggshells and provides evidence for the distribution into the eggshells after administration of these drugs to laying hens. The enrofloxacin residues were detected in the eggshell for 10 d after cessation of treatment, ciprofloxacin and lincomycin were rapidly eliminated and 2 d after finish drugs administration they were no longer detected in the eggshell.

The incidence of antibiotic resistance is on the rise and becoming a major health concern. Analyzing the presence of antibiotic compounds in the environment is critical for determining the potential health effects for humans, animals, and ecosystems. For this study, methods were developed to simultaneously isolate and quantify four antibiotics important in human medicine (sulfamethoxazole—SMX, trimethoprim—TMP, lincomycin—LIN, and ofloxacin—OFL) in water and soil matrices. For water analysis, different solid phase extraction (SPE) cartridges (Oasis HLB plus and Phenomenex Strata-X) were compared. The Oasis HLB Plus SPE cartridge provided the highest and most consistent recoveries with 118 ± 5%, 86 ± 4%, 83 ± 5%, and 75 ± 1% for SMX, TMP, LIN, and OFL, respectively. For soil analysis, different pre-treatments (grinding and freeze-drying) and soil extraction methodologies (liquid-solid extraction and accelerated solvent extraction (ASE)) were compared. The ASE system resulted in the highest overall recoveries of SMX, TMP, LIN, and OFL with an optimal extracting solution of acetonitrile/water (v/v, 50:50, pH 2.8). When the soil was ground and freeze-dried, trimethoprim recovery increased and when soil was ground, but not freeze-dried, LIN and OFL recoveries increased, while sulfamethoxazole recoveries decreased when soil was ground and freeze-dried. Based on this research, matrix characteristics, especially pH, as well as the pKa’s and functional groups of the antibiotics need to be carefully considered when attempting to extract antibiotic compounds from a water or soil environment.

The control of Mycoplasma hyorhinis infection relies mainly on antimicrobial therapy. However, the antibiotic susceptibility testing of the bacteria is usually not performed before applying the treatment, and thus therapeutic failures are not uncommon. In the case of M. hyorhinis, several antibiotic-resistance-related single nucleotide polymorphisms (SNPs) are known but assays for their detection have not been described yet. The aims of the present study were to investigate macrolide- and lincomycin-resistance-related SNPs in Hungarian M. hyorhinis isolates and to develop mismatch amplification mutation assays (MAMA) to detect the identified resistance markers. Minimal inhibitory concentrations (MIC) of different drugs and whole genome sequences of 37 M. hyorhinis isolates were used to find the resistance-related mutations. One MAMA assay was designed to detect the mutation of the 23S rRNA gene at nucleotide position 2058 (Escherichia coli numbering). For further evaluation, the assay was challenged with 17 additional isolates with available MIC data and 15 DNA samples from clinical specimens. The genotypes of the samples were in line with the MIC test results. The developed assay supports the practice of targeted antibiotic usage; hence it may indirectly reduce some bacterial resistance-related public health concerns. [ABSTRACT FROM AUTHOR]

Acipenser dabryanus is designated as a critically endangered species on the IUCN Red List and known as a first‐class protected animal in China. Recently, A. dabryanus fries (approximately 45 days old) in a fishery institute in south‐western China suffered from a high rate of mortality. In this study, a strain of Plesiomonas shigelloides was isolated from the liver and heart of the infected fry, named 22S, and confirmed to be related to the mortality of A. dabryanus fries. Plesiomonas shigelloides was identified using biochemical characterization and molecular analysis. A 16S rDNA gene sequence alignment analysis found that the isolate shared 100% homology with P. shigelloides (NCBI GenBank Accession Number—NR 044827) in this gene. Antimicrobial susceptibility testing showed that 22S was resistant to penicillin, oxacillin, clindamycin, trimethoprim and lincomycin and sensitive to nitrofurantoin, levofloxacin tablets and norfloxacin. The LD50 value was 5.94*105 cfu/g. Clinical symptoms of challenged fish were the same as those of naturally infected fish. Histopathology of the infected fish showed that the viscera and gill were severely damaged. This is the first report suggesting that P. shigelloides infection is associated with mass mortality of A. dabryanus. The results of this study elucidate the pathogenesis and severe pathogenicity of P. shigelloides in cultured A. dabryanus and highlight the need for appropriate disease control and prevention measures. [ABSTRACT FROM AUTHOR]

The current emergence of antimicrobial resistance against colistin is a major challenge to treat multi drug resistant Gram negative bacteria. Broiler chickens can function as a source for dissemination of antimicrobial resistant strains to humans. In present study, 150 cloacal swabs of broiler birds, collected from retail shops in Lahore, were processed for isolation of E. coli. E. coli isolates (n=100) were tested for antimicrobial sensitivity to colistin sulfate using broth dilution method. The resistant isolates were tested by polymerase chain reaction for mcr-1 and mcr-2 genes of colistin resistance. The isolates, found resistant by broth dilution method, were also checked for pathogenicity by adding congo-red dye in nutrient agar. Phenotypically colistin resistant isolates were also tested for other antibiotics e.g. Amoxicilline (30ug), Cefepime (30ug), Gentamycin (10ug), Chloramphenicol (30mcg), Clindamycin (2ug), Ciprofloxacine (5ug), Norfloxacin (10ug), Amikacin (30ug), Lincomycin (10ug) and Streptomycin (10ug) by disc diffusion method. Out of 100 isolates, 59 showed resistance to colistin while taking MIC as 4mg/L. The colistin resistant E. coli also showed multidrug resistance against other antibiotics tested. Among 59 phenotypically colistin resistant isolates, only 7 isolates were possessing mcr-1 gene but none of the strains was observed bearing mcr-2 gene. About 15% (5/59) colistin resistant isolates were pathogenic by congo red dye test. The results indicated presence of mcr-1 harboring E. coli in commercial birds that can contribute in spread of mcr-1 gene. [ABSTRACT FROM AUTHOR]

In the present study, a total of 120 milk samples (50 clinical and 70 subclinical mastitis cases) collected from buffaloes located at different localities at El-Behera Governorate, Egypt were examined phenotypically and genotypically for the presence of S. aureus and coagulase-negative staphylococci. Results showed that 42 S. aureus and 20 coagulase-negative Staphylococcus species isolates were recovered from the examined 120 milk samples. A total of 40 S. aureus and coagulase-negative staphylococci were further identified based on the amplification of 16S rRNA, coa, clfA, and nuc encoding genes. Results revealed that all S. aureus isolated from clinical and subclinical cases were found to harbor 16S rRNA, coa, clfA, and nuc encoding genes. Resistance against 12 antibiotics was determined using disc diffusion methods. All the tested S. aureus and coagulase-negative staphylococcal isolates exhibited resistance to amoxicillin, ampicillin, cefotaxime, ciprofloxacin, cloxacillin, oxacillin, lincomycin, penicillin, and trimethoprim/sulphamethoxazole. Constitutive production of mecA and blaZ encoding resistance against penicillin and cloxacillin was reported in 70% and 20% of S. aureus and 80 % and 30% of the coagulase-negative staphylococcal isolated from clinical and subclinical mastitis, respectively. In contrast, all isolates found to harbor the specific amplicon of the sul1 gene. The amplicon of aac(6”)-aph(2”) encoding resistance gene was observed in only 6 S. aureus isolates. The specific amplicon of norA gene was detected in 4 S. aureus and 2 coagulase-negative staphylococcal isolates recovered from clinical mastitis. To conclude, the emergence of multi-drug resistant S. aureus and coagulase-negative staphylococci as a cause of mastitisin dairy farms is of public health concern requires further investigations. [ABSTRACT FROM AUTHOR]

This correction notice addresses an error in an article titled "Impact of buffered sodium butyrate as a partial or total dietary alternative to lincomycin on performance, IGF-1 and TLR4 genes expression, serum indices, intestinal histomorphometry, Clostridia, and litter hygiene of broiler chickens." The mistake was in the description of a feed additive called Butirex C4®. The original version incorrectly stated that it was produced by Avitech Nutrition Pvt. Ltd. in India, but it should have been attributed to Novation in Spain. The article has been updated to reflect this correction. [Extracted from the article]

[Display omitted] • Biochar amended composting reduced the abundance of intra- and extracellular ARGs. • Biochar, bacterial community and MGEs contributed to iARGs and eARGs removal. • Biochar inhibited eARGs transformation and RP4 plasmid conjugative transfer. • Biochar could destroy the structural and functional integrity of cells. • Biochar altered the expression of mRNA including ROS and SOS related genes. This study aims to indicate the influence of biochar on extracellular and intracellular ARGs (e/iARGs) variation and proliferation during lincomycin fermentation dregs (LFDs) compost. Biochar addition made iARGs keep reducing but eARGs increase to the maximum at the middle thermophilic phase and reduce at the end of the compost. Compared to control 3.15-log and 5.42-log reduction of iARGs and eARGs were observed, respectively. Biochar addition, bacterial community, and MGEs were the major contributors to iARGs and eARGs removal, with the contribution percentages of 38.4%, 31.0%, 23.7%, and 27.2%, 29.1%, and 34.9%, respectively. Moreover, biochar significantly inhibited eARGs transformation and RP4 plasmid conjugative transfer among E. coli DH5α and Pseudomonas aeruginosa HLS-6. The underlying mechanism involved in broken cell membranes of bacteria, and altered expression of oxidative stress genes and save our souls (SOS) response-related genes. The results indicated that biochar addition in composting could limit the dissemination of ARGs. [ABSTRACT FROM AUTHOR]

Lincomycin (LCM) is an antibiotic used to treat severe bacterial infections in livestock and companion animals. In this study, we aimed to investigate the oral bioavailability of LCM with PK data after IV and PO administration and to compare differences in drug residue patterns in eggs. To ensure food safety, an additional study on egg residue was conducted using 3 different commercial LCM drugs. For bioavailability study, laying hens were divided into oral and intravenous (n = 8/group) groups and received single dose (10 mg/kg) of LCM. The limits of quantification for LCM were 0.729 μg/mL and 0.009 mg/kg in plasma and eggs, respectively. The oral group exhibited a significantly lower average serum drug concentration than the IV group, with a bioavailability of 2.6%. Furthermore, the egg residue profiles confirmed reduced systemic drug exposure after oral administration. For the commercial LCM drug egg residue experiment, laying hens were divided into low- and high-dose groups (n = 12/group) for each drug and treated with the recommended dosage and administration method for each respective drug. The eggs were collected and analyzed until 14 d after the last drug treatment. Despite differences in the LCM content and formulation among commercial drugs, all the tested commercial drugs showed average concentrations below the MRL in eggs within approximately 3 d after the last drug treatment. In this study, we have confirmed that LCM has a low oral absorption rate in laying hens, and this was consistent with the findings from the egg residue profiles. Further studies are requested to elucidate the exact reasons for evidently low oral drug absorption in laying hens. [ABSTRACT FROM AUTHOR]

Veterinary antibiotics and estrogens are excreted in livestock waste before being applied to agricultural lands as fertilizer, resulting in contamination of soil and adjacent waterways. The objectives of this study were to 1) investigate the degradation kinetics of the VAs sulfamethazine and lincomycin and the estrogens estrone and 17β-estradiol in soil mesocosms, and 2) assess the effect of the phytochemical DIBOA-Glu, secreted in eastern gamagrass (Tripsacum dactyloides) roots, on antibiotic degradation due to the ability of DIBOA-Glu to facilitate hydrolysis of atrazine in solution assays. Mesocosm soil was a silt loam representing a typical claypan soil in portions of Missouri and the Central United States. Mesocosms (n = 133) were treated with a single target compound (antibiotic concentrations at 125 ng g−1 dw, estrogen concentrations at 1250 ng g−1 dw); a subset of mesocosms treated with antibiotics were also treated with DIBOA-Glu (12,500 ng g−1 dw); all mesocosms were kept at 60% water-filled pore space and incubated at 25 °C in darkness. Randomly chosen mesocosms were destructively sampled in triplicate for up to 96 days. All targeted compounds followed pseudo first-order degradation kinetics in soil. The soil half-life (t 0.5) of sulfamethazine ranged between 17.8 and 30.1 d and ranged between 9.37 and 9.90 d for lincomycin. The antibiotics results showed no significant differences in degradation kinetics between treatments with or without DIBOA-Glu. For estrogens, degradation rates of estrone (t 0.5 = 4.71–6.08 d) and 17β-estradiol (t 0.5 = 5.59–6.03 d) were very similar; however, results showed that estrone was present as a metabolite in the 17β-estradiol treated mesocosms and vice-versa within 24 h. The antibiotics results suggest that sulfamethazine has a greater potential to persist in soil than lincomycin. The interconversion of 17β-estradiol and estrone in soil increased their overall persistence and sustained soil estrogenicity. This study demonstrates the persistence of these compounds in a typical claypan soil representing portions of the Central United States. [Display omitted] • All targeted compounds followed pseudo first-order degradation kinetics. • DBG driven hydrolysis did not play a significant role in affecting veterinary antibiotic half-lives. • Lincomycin degradation was 2–3 times faster in soil than sulfamethazine. • Degradation rates of estrone and 17β-estradiol in soil were comparatively similar. • Estrone and 17β-estradiol interconversion in soil increased their overall persistence. [ABSTRACT FROM AUTHOR]

The excessive accumulation of antibiotic residue in animal-derived foods pose a threat to our heath. Therefore, it is necessary to establish a rapid, simple, effective, safe and highly sensitive lincomycin (LIN) residues detection method by high-performance liquid chromatography equipped with ultraviolet. Here, due to the weak UV absorption of LIN, the p -Toluenesulfonyl isocyanate (PTSI, has a strong UV absorption) was binded to the hydroxyl group of LINs by using pre-column derivatization method, improving the UV absorption of LIN. This 9-min-run analytical method detects and quantifies LIN residues with acceptable validation performance parameters in terms of sensitivity, selectivity, linearity, the limit of quantification, accuracy, and precision.Our result showed that the limits of detection and quantification for LIN in samples were 25–40 μg/kg and 40–60 μg/kg, respectively, under the optimized conditions. Furthermore, the LIN recoveries ranged from 72.4 % to 96.7 %; the determination coefficients were 0.9912–0.9996, and the relative standard deviations were 5.6 %-12.7 %. Therefore, the HPLC-UVD method for detecting LIN residues in animal-derived food products has been established. [ABSTRACT FROM AUTHOR]

Abstract Lincomycin A is a clinically important antibiotic produced by Streptomyces lincolnensis that is used against gram-positive bacteria. To increase the yield of lincomycin A, a calcium gluconate feeding strategy was studied in a 15 L bioreactor. The results showed that the addition time of calcium gluconate was optimal during the late fermentation process to ensure a higher yield of lincomycin A. The optimum addition was continuous feeding at a speed of 0.0638 g/L/h from 111 to 158 h, which can increase the lincomycin A titer to 9160 mg/L, 41.3% higher than that without gluconate feeding. Enzyme activities of the central metabolic pathways, accumulation of intermediate metabolites, NADPH and NADH concentrations, and NADPH/NADH ratio were determined to investigate the mechanism of enhanced lincomycin A production by calcium gluconate addition. The activities of key enzymes of the pentose phosphate pathway (PPP) (glucose 6-phosphate dehydrogenase) and TCA cycle (isocitrate dehydrogenase) were enhanced by approximately twofold. A higher ratio of NADPH/NADH was observed in the fermentation process with the optimized feeding strategy providing sufficient reducing power. These data indicated that more flux flows through the PPP and the TCA cycle to provide more precursors, ATP and reducing power to support the synthesis of lincomycin A. The results showed a new strategy to improve the production of lincomycin A by manipulating the flux through the PPP and the TCA cycle.

The adverse effects of short-term megadose of antibiotics exposure on the gastrointestinal and liver tissue reactions in young children have been reported. Antibiotic-induced intestinal and liver reactions are usually unpredictable and present a poorly understood pathogenesis. It is, therefore, necessary to develop strategies for reducing the adverse effects of antibiotics. Studies on the harm and rescue measures of antibiotics from the perspective of the gut–liver system are lacking. Here, we demonstrate that lincomycin exposure reduced body weight, disrupted the composition of gut microbiota and intestinal morphology, triggered immune-mediated injury and inflammation, caused liver dysfunction, and affected lipid metabolism. However, baicalin administration attenuated the lincomycin-induced changes. Transcriptome analysis showed that baicalin improved immunity in mice, as evidenced by the decreased levels of intestinal inflammatory cytokines and expression of genes that regulate Th1, Th2, and Th17 cell differentiation, and inhibited mucin type O-glycan biosynthesis pathways. In addition, baicalin improved liver function by upregulating the expression of genes involved in bile acid secretion and lipid degradation, and downregulating genes involved in lipid synthesis in lincomycin-treated mice. Bile acids can regulate intestinal immunity and strengthen hepatoenteric circulation. In addition, baicalin also improved anti-inflammatory bacteria abundance (Blautia and Coprobacillus) and reduced pathogenic bacteria abundance (Proteobacteria, Klebsiella, and Citrobacter) in lincomycin-treated mice. Thus, baicalin can ameliorate antibiotic-induced injury and its associated complications such as liver disease.

This study evaluated the occurrence of PPCPs in Cau River (Vietnam). Surface water and sediment samples were collected to determine PPCP concentrations. The analysis results showed the presence of 36 out of 56 investigated PPCPs in samples. The total concentration of PPCPs in water samples ranged from 8.21 to 529 ng/L and the value observed in sediment was from 17.4 to 172.8 μg/kg. Along the Cau River, there was a trend of accumulation of PPCPs at the downstream. The highest level of PPCP was observed after the river flows through Thai Nguyen and Bac Ninh provinces. Among detected PPCPs, the ones detected with high frequency (over 70%) and high concentration were caffeine, sulfamethoxazole, and lincomycin in water and triclocarban, levofloxacin, and griseofulvin in sediment. The water-sediment partition coefficient (Kd) was estimated to explore the fate of PPCP in the river, and the observed Kd mean values for lincomycin, sulfamethoxazole, and griseofulvin were 223.0, 7.6, and 997.0 kg/L, respectively. Risk assessment was initially conducted by applying a semi-quantitative assessment risk quotient (RQ); the potential ecological risk to the aquatic organism of PPCPs posed a moderate risk. [ABSTRACT FROM AUTHOR]

Residual antibacterial agents in 5909 animal and fishery products in Tokyo, Japan, were investigated over 17 consecutive years (2003–2019). Monitoring of 32 antibacterial agents (lincosamides, macrolides, penicillins, quinorones and tetracyclines) per product was accomplished via two steps: screening (by microbiological methods) and confirmation (by instrumental methods). Microbiological screening methods identified presumptive groups and determined semi-quantitative values. The instrumental methods quantified 81 residues of 11 different antibacterial agents in 72 samples. The screening strategy based on microbiological methods demonstrated the following: (i) the majority of the samples (over 99%) met Japanese regulations, (ii) using multiple methods provided a reliable inspection system with accurate quantitative values and (iii) there was a constant presence of tetracyclines and unexpected residues (lincomycin and norfloxacin) in various products. Thus, this long-term monitoring and screening strategy provided evidence that the frequencies and trends of residual antibacterial agents not only enhance food safety but also help to prevent antimicrobial resistance. [ABSTRACT FROM AUTHOR]