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Cronobacter is an emerging bacterial pathogen associated with infections such as necrotizing enterocolitis, sepsis, and meningitis in neonates and infants, related to the consumption of powdered infant formula. In addition, this bacterium can also cause infections in adults by the ingestion of other foods. Thus, this review article aims to report the occurrence and prevalence of Cronobacter spp. in foods of plant origin, as well as the possible sources and routes of contamination in these products, and the presence of pathogenic strains in these foods. Cronobacter was present in a wide variety of cereal-based foods, vegetables, herbs, spices, ready-to-eat foods, and foods from other categories. This pathogen was also found in cultivation environments, such as soils, compost, animal feces, rice and vegetable crops, as well as food processing industries, and domestic environments, thus demonstrating possible contamination routes. Furthermore, sequence types (ST) involved in clinical cases and isolates resistant to antibiotics were found in Cronobacter strains isolated from food of plant origin. The identification of Cronobacter spp. in plant-based foods is of great importance to better elucidate the vehicles and routes of contamination in the primary production chain and processing facility, until the final consumption of the food, to prevent infections. [ABSTRACT FROM AUTHOR]

Cronobacter is an emerging bacterial pathogen associated with infections such as necrotizing enterocolitis, sepsis, and meningitis in neonates and infants, related to the consumption of powdered infant formula. In addition, this bacterium can also cause infections in adults by the ingestion of other foods. Thus, this review article aims to report the occurrence and prevalence of Cronobacter spp. in foods of plant origin, as well as the possible sources and routes of contamination in these products, and the presence of pathogenic strains in these foods. Cronobacter was present in a wide variety of cereal-based foods, vegetables, herbs, spices, ready-to-eat foods, and foods from other categories. This pathogen was also found in cultivation environments, such as soils, compost, animal feces, rice and vegetable crops, as well as food processing industries, and domestic environments, thus demonstrating possible contamination routes. Furthermore, sequence types (ST) involved in clinical cases and isolates resistant to antibiotics were found in Cronobacter strains isolated from food of plant origin. The identification of Cronobacter spp. in plant-based foods is of great importance to better elucidate the vehicles and routes of contamination in the primary production chain and processing facility, until the final consumption of the food, to prevent infections. [ABSTRACT FROM AUTHOR]

The general objective of this work was to isolate from yoghourts cultured strains of lactobacilli with potential for use as probiotics in poultry farming. Three yoghourts were cultured to see the presence of lactobacilli in the Rogosa agar base culture medium. It was found that only one yoghourt (number 1) showed the growth of lactobacilli. This yoghourt was immediately selected for further cultivation. Afterwards, the Lactobacillus strains were isolated and fortified under CO2 and then inoculated into a solution of peptone water, which constituted inoculums to be administered to an experimental group of poultry. Another group served as controls. Pathogenic strains of Escherichia coli were also administered to both groups (experimental and control, each comprising five hens). The results showed significant weight gain from the experimental group (positive effect on immunity) and freedom from disease after an incubation period (inhibitory effect of the lactobacillus strains on the Escherichia coli strains), whereas the control group showed less weight gain than the experimental group and development of colibacillosis after an incubation period. The positive effects of the Lactobacillus strains observed on the poultry of the experimental group proved the ecological role of these microorganisms in improving the health of the poultry by inhibiting the effects of pathogenic Escherichia coli strains. This suggests reassuring prospects for the reduction of antibiotic use in both human and animal care. [ABSTRACT FROM AUTHOR]

Many antimicrobial compounds have been seeking to protect the human body against pathogenic microbial infections. In recent times, there has been considerable growth of pathogens resistant to existing drugs due to the inappropriate use of antibiotics. In the present study, bacteria isolated from the honey of stingless bees native to the Amazon called Scaptotrigona aff. postica and Apis mellifera were used to determine their potential antimicrobial properties and characterize the medium cultivated with isolated bacteria. The results showed inhibition of nine isolates. Among these isolates, SCA12, SCA13, and SCA15 showed inhibitory activity similar to that of vancomycin, which was used as a positive control. The SCA13 strain obtained the best results with antimicrobial extract against the tested pathogens; the species was identified as Enterococcus faecalis, and its lyophilized extract was characterized by temperature, pH, and trypsin, in which they showed antimicrobial activity. This work shows that bacteria isolated from the stingless bee honey, Scaptotrigona aff. postica, have the potential to produce antimicrobial substances. [ABSTRACT FROM AUTHOR]

Pathogenic strains of Escherichia coli threaten public health due to their virulence factors and antibiotic resistance. Additionally, the virulence of this bacterium varies by region depending on environmental conditions, agricultural practices, and the use of antibiotics and disinfectants. However, there is limited research on the prevalence of antibiotic-resistant E. coli in agriculture. Therefore, this research aimed to determine the antibiotic resistance of E. coli isolated from the Honeydew melon production system in Hermosillo, Sonora, Mexico. Thirty-two E. coli strains were isolated from 445 samples obtained from irrigation water, harvested melons, the hands of packaging workers, boxes, and discarded melons. The resistance profile of the E. coli strains was carried out to 12 antibiotics used in antimicrobial therapeutics against this bacterium; a high level of resistance to ertapenem (100%) was detected, followed by meropenem (97%), and ampicillin (94%); 47% of the strains were classified as multidrug-resistant. It was possible to identify the prevalence of the extended-spectrum β-lactamase (ESBLs) gene blaTEM (15.6%), as well as the non-ESBL genes qepA (3.1%) and aac(6′)lb-cr (3.1%). The E. coli strains isolated from irrigation water were significantly associated with resistance to aztreonam, cefuroxime, amikacin, and sulfamethoxazole/trimethoprim. Irrigation water, packing workers' hands, and discarded melons showed a higher prevalence of antibiotic-resistant, ESBL, and non-ESBL genes of E. coli strains in a farm and packing facility of Honeydew melon in Hermosillo, Sonora. [ABSTRACT FROM AUTHOR]

The objective of the present study is to the total phenolic compound determination, as well as the in vitro evaluation of methanolic and ethanolic extracts antimicrobial activity of the medicinal plant Mentha rotundifolia L. against pathogenic strains. The Follin-Cioacalteu method was used to determine the total polyphenols, while the flavonoids were estimated according to the colorimetric method with aluminum chloride. In addition, the determination of condensed tannins is performed by the vanillin method. The antimicrobial activity is tested on five pathogenic bacterial strains, two of which are Gram-negative (Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853), three Gram-positive (Bacillus cereus ATCC 11778, Staphylococcus aureus ATCC 25923 and Micrococcus leutus ATCC 4698), and one yeast (Candida albicans ATCC 26790), by the diffusion on solid medium and microdilution methods. The ethanolic extract of round leaf mint from the Bechar region is very rich in polyphenols and flavonoids (401.75 ± 0.32 mg GAE/g, 549.75 ± 1.23 mg QE/g) compared to the methanolic and hydroalcoholic extracts of this plant from the Sidi-Bel-Abbes region. The results of the obtained well method showed that all bacterial strains exhibited sensitivity to the ethanolic extract of Mentha rotundifolia L. from the Bechar region, with inhibition zones up to 21,67 ± 0,57 mm and minimum inhibitory concentrations (MIC) varying between 06.25 mg/ml and 100 mg/ml, The effect of the other extracts on the tested strains was less significant, the methanolic extract was the least effective. These results demonstrate that the Mentha rotundifolia L. ethanolic extract has a great potential of secondary metabolites with antimicrobial activity. [ABSTRACT FROM AUTHOR]

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant diseases are the serious threat to global food security. Many of the current antimicrobial agents for agriculture are highly toxic and non-biodegradable and cause prolonged environmental pollution. In this present research work, seed extract of corn has been used to reduce silver nitrate for the biosynthesis of silver nanoparticles (AgNPs) and to evaluate antimicrobial activity against pathogenic bacterium and fungus. The synthesised biogenic silver nanoparticles (AgNPs) were characterised by UV-Vis, FTIR, XRD, SEM, EDX, TEM and DLS. Scanning electron microscopic (SEM) and Transmission electron microscope (TEM) elicit the formation of spherical-shaped nanoparticles with an average size of 25 nm. X-ray diffraction revealed the FCC nature of nanoparticles. Biosynthetic AgNPs have been shown to be a valuable inhibitory activity against the phytopathogenic fungus Phomopsis vexans by reducing the growth of mycelium by 30–40% in potato dextrose medium. It has been concluded that corn seed extract is capable of synthesising AgNPs with antifungal activity. [ABSTRACT FROM AUTHOR]

Introduction: Cardamom, also known as Elettaria cardamomum, a venerated perennial herb like the "Queen of Spices" belongs to the Zingiberaceae family. She holds various pharmacological activities due to its phytochemicals it contains such as; phenols, tannins, terpenoids, flavonoids, sterols. Methods: The study included the determination of the chemical composition of Elettaria cardamomum ethanolic extract (EEC) by HPLC/UV and evaluated their antimicrobial potential against ten pathogenic reference strains using two complementary techniques: the method of diffusion from solid discs and the determination of minimum inhibitory concentrations (MIC). Results: The results obtained from chemical identification of the EEC showed the presence of polyphenolic acids (rosmarinic acid, caffeic acid, ferulic acid, etc.) and many flavonoids (kaempferol, chrysin, galangin, pinocembrine, quercetin, etc.). The results of the antimicrobial effect showed that the extract reacted positively on almost all the microbial strains tested. The EEC extract significantly inhibited the growth of microbial strains, with a broader antimicrobial spectrum with extensive action with inhibitory zones between 8 and 33 mm in diameter. Thus, this extract revealed a dose-dependent antimicrobial activity on these microbial strains used. However, the inhibitory potential of the cardamom extract was variable compared to their MIC ranging from 6.25 to 12.5 mg of dry extract/mL. Therefore, the strains least susceptible to EEC are Bacillus subtilis, Escherichia coli, Aspergillus niger and Candida albicans. Conclusion: This activity is due to the phenolic compounds produced by the EEC extract. This extract can be used for the development of plant medicines against microbial infections and fungal infestations. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wine has long been under the view of researchers to test it for prospective benefits to human health. Many recent studies have claimed how moderate consumption of wine, can be beneficial for us. The aim of this study was to assess antagonistic activity and probiotic potential of the LAB strains, Lactobacillus brevis, Lactobacillus hilgardii and Lactobacillus plantarum, isolated from wine against pathogenic bacteria. The antimicrobial activity was detected with disc diffusion method against five species of Gram-negative bacteria: Escherichia coli CCM 3988, Klebsiella pneumoniae CCM 2318, Salmonella enterica subsp. enterica CCM 3807, Shigella sonei CCM 1373, Yersinia enterocolitica CCM 5671 and five Gram-positive bacteria: Bacillus thuringiensis CCM 19, Enterococcus faecalis CCM 4224, Listeria monocytogenes CCM 4699, Stapylococcus aureus subsp. aureus CCM 2461, Streptococcus pneumonia CCM 4501. These results showed antagonistic activity and probiotic potential of pathogenic bacteria isolated from wine. The cell free supernatants (CFS) from Lactobacillus brevis, Lactobacillus hilgardii and Lactobacillus plantarum inhibited the growth of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Garlic (Allium sativum L.) and onion (Allium cepa L.) are ones of the most promising medicinal herbs known from ancient times having nutritional value. Nutrients found in these medicinal plants play important roles in curing different diseases and disorders. Therefore, the present study aimed to determine the physico-chemical characteristics of cultivated varieties of garlic and onion and evaluate the antibacterial activity of these plants by disk diffusion method against three pathogenic strains including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Bacillus subtilis ATCC 25332.The physico-chemical analysis executed was pH, titratable acidity, moisture, ash, total soluble solids, electrical conductivity, viscosity, proteins, fats, crude fiber, pectin, total and reducing sugars and minerals. It was found that these plants are good source of proteins, fats, fibers, minerals and energy. For the results of antibacterial activity, methanol extract obtained from these plants revealed the sensitivity on the tested pathogenic strains. The strongest antibacterial effect on tested strains was found in garlic extracts. [ABSTRACT FROM AUTHOR]

The present work is emphasised on the bio‐fabrication of silver and gold nanoparticles in a single step by a microwave‐assisted method using the leaf extract of Synedrella nodiflora as both reducing and stabilising agent. The synthesised nanoparticles are highly stable and show surface plasmon resonance peak at 413 and 535 nm, respectively, for silver and gold nanoparticles in UV–Vis spectrum. The functional group responsible for the reduction of metal ions were obtained from Fourier transform infrared spectroscopy. The crystalline nature of nanoparticles with face‐centred cubic geometry was confirmed by the X‐ray diffraction and selected area electron diffraction patterns. The morphology and sizes of the silver and gold nanoparticles were obtained from transmission electron microscopy images. The nanoparticles exhibit effective antimicrobial activities against various pathogenic strains. These antimicrobial properties were analysed by employing agar well diffusion method. The nanoparticles show significant antioxidant properties, and it was determined using 2, 2‐diphenyl‐1‐picrylhydrazyl assay. The nanoparticles also show potent catalytic activity in the degradation of anthropogenic pollutant dyes Congo red and eosin Y by excess NaBH4. Thus, the current study demonstrates the potential use of S. nodiflora as a reducing and stabilising agent for the synthesis of silver and gold nanoparticles and their relevance in the field of biomedicine and catalysis. [ABSTRACT FROM AUTHOR]

The current research study focuses on biosynthesis of silver nanoparticles (Ag NPs) for the first time from silver acetate employing methanolic root extract of Diospyros assimilis. The UV–Vis absorption spectrum of biologically synthesised nanoparticles displayed a surface plasmon peak at 428 nm indicating the formation of Ag NPs. The influence of metal ion concentration, reaction time and amount of root extract in forming Ag NPs by microscopic and spectral analysis was thoroughly investigated. Structural analysis from transmission electron microscopy confirmed the nature of metallic silver as face‐centered cubic (FCC) crystalline with an average diameter of 17 nm, which correlates with an average crystallite size (19 nm) calculated from X‐ray diffraction analysis. Further, the work was extended for the preliminary examination of antimicrobial activity of biologically synthesised Ag NPs that displayed promising activity against all the tested pathogenic strains. [ABSTRACT FROM AUTHOR]

In the present study, the effect of different in vitro cultures (callus, in vitro shoots) and commercially available peppercorn extract was investigated for its activity against toxic metabolite-producing strains (Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Candida albicans). These in vitro cultures were extracted with ethanol, hexane, and chloroform, and the antipathogenic activity was determined by well-diffusion method. Hexane extract of callus showed 22 mm zone of inhibition against B. cereus, 23 mm against S. aureus, while regenerated shoots and seeds have shown 24.3 and 26 mm zones of inhibition. The ethanolic extracts of regenerated Piper shoots have shown 25 mm activity against S. aureus, 21 mm against B. cereus, and 16 mm in the case of C. albicans in comparison with standard antibiotics. Peppercorn extracts in chloroform and ethanol had shown activities against B. cereus (23.6 mm) and B. subtilis (23.5 mm). During in vitro organogenesis and morphogenesis, cells and tissues produced a comparable phytochemicals profile like mother plant. Morphogenesis is critically controlled by the application of exogenous plant-growth regulators. Such addition alters the hormonal transduction pathways, and cells under in vitro conditions regenerate tissues, which are dependant on the physiological state of cells, and finally enhance the production of secondary metabolites. To the best of our knowledge, this is the first report to compare the antimicrobial potential of in vitro regenerated tissues and peppercorn with standard antibiotics. In conclusion, most of the extracts showed pronounced activities against all the pathogenic microbes. This is a preliminary work, and the minimum inhibitory concentration values needs to be further explored. Regenerated tissues of P. nigrum are a good source of biologically active metabolites for antimicrobial activities, and callus culture presented itself as a good candidate for such activities. [ABSTRACT FROM AUTHOR]

Green synthesis of metallic nanoparticles has lured the world from the chemical and physical approaches owing to its rapid, non‐hazardous and economic aspect of production mechanism. In this study, silver nanoparticles (AgNPs) were synthesised using petal extracts of Hibiscus rosa‐sinensis. The AgNPs displayed characteristic surface plasmon resonance peak at around 421 nm having a mean particle size of 76.25 ± 0.17 nm and carried a charge of −41 ± 0.2 mV. The X‐ray diffraction patterns displayed typical peaks of face centred cubic crystalline silver. The surface morphology was characterised by scanning electron microscopy and atomic force microscopy. Fourier transform infrared spectroscopy studies confirmed the surface modifications of the functional groups for the synthesis of AgNPs. Furthermore, the synthesised AgNPs displayed proficient antimicrobial activity against pathogenic strains of Vibrio cholerae, Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

This is a report on the synergistic interactions (SIs) between melampolide-type sesquiterpene lactones 1-8 from Acanthospermum hispidum DC., and oxacillin or gentamicin, against four pathogenic strains of Staphylococcus aureus and Enterococcus faecalis; two of them were multi-resistant strains obtained from chronic infectious processes. Our results showed that all associations of 1-8 with antibiotics (ATBs) are more effective than pure ATBs to control pathogenic strains of S. aureus and E. faecalis. The most relevant SIs were observed when the major lactone of A. hispidum, acanthospermal B [5], was combined with gentamicin (protein synthesis inhibitor) against an ex vivo culture of methicillin-resistant S. aureus SAR 1, displaying a significant MIC reduction in 5 (312.5 to 78.1 µg/mL), and gentamicin (120 µg/mL to 3 µg/mL). Compound 4 improved the antibiotic potency of oxacillin (cell wall synthesis inhibitor) against ampicillin-resistant E. faecalis (60 µg/mL to 1.5 µg/mL). It is important to remark that three beneficial lactobacilli were resistant to 1-8 and their mixtures with gentamicin or oxacillin in effective concentrations against pathogenic bacteria. Synergism between ATBs and phytochemicals is a therapeutically helpful concept to improve ATB efficacy and prevent resistance. The present results show that selective SIs occur between melampolides and gentamicin or oxacillin, and open a new field of research. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The pathogenicity of smut fungi is initiated by the fusion of two compatible saprotrophic yeasts that give rise to the formation of dikaryotic pathogenic hyphae. It has been described in the literature that complementation assays of auxotrophic yeasts of Ustilago maydis have allowed the isolation of diploid strains that are solopathogenic, i.e. pathogenic in the absence of mating. The occurrence of such strains from germinating teliospores was not investigated. We evaluated the ability of teliospores to generate solopathogenic strains in three species of smut fungi: Sporisorium reilianum f.sp. zeae, U. maydis and Moesziomyces penicillariae. Using an approach based on the stability of pseudohyphae of solopathogenic strains, we isolated the strain SRZS1 from teliospores of S. reilianum. Microscopic observations and analyses of mating-type alleles showed that SRZS1 is monokaryotic and diploid. Inoculation tests on maize plantlets indicated that SRZS1 is infectious. The same protocol was applied to polyteliosporal isolates from M. penicillariae, U. maydis and S. reilianum of diverse geographic origin. Surprisingly, all strains from teliospores of M. penicillariae were solopathogenic, whereas only few solopathogenic strains were obtained from the other two species. The possible incidence of solopathogenic strain production in the biology of these species is discussed. [ABSTRACT FROM AUTHOR]

Rauwolfia serpentina (R. serpentina), belonging to the family Apocynaceae, is a renowned medicinal herb for its different pharmacological activities such as antibacterial, antifungal, anti-inflammatory, and antiproliferative characteristics. This study has done a comparative assessment of the antibacterial, antioxidant, and anti-cancer activity of R. serpentina aqueous leaf extract (RSALE) with encapsulated gold nanoparticles (R-AuNPs). The R-AuNPs are prepared so that they are significant in size, monodispersed, and extremely stable. Their characterization was done by numerous parameters, including UV-visible spectroscopy (528 nm), transmission electron microscopy (~17 d. nm), dynamic light scattering (~68 d. nm), and zeta-potential (~−17 mV). Subsequently, a potent antibacterial activity was depicted via RSALE and R-AuNPs when examined by disc diffusion against various Gram-positive and Gram-negative bacterial strains. The obtained zones of inhibition of RSALE (100 mg/mL) were 34 ± 0.1, 35 ± 0.1, 28.4 ± 0.01, and 18 ± 0.01, although those of R-AuNPs (15 mg/mL) were 24.4 ± 0.12, 22 ± 0.07, 20 ± 0.16, and 17 ± 0.3 against Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Bacillus subtilis (MTCC 8114), and Streptococcus pyogenes (ATCC 19615), respectively. However, no zone of inhibition was obtained when tested against Proteus vulgaris (MTCC 1771). Furthermore, the obtained MIC values for Staphylococcus aureus were 0.91, 0.61, and 1.15 mg/mL; for Escherichia coli, 0.79, 0.36, and 1.02 mg/mL; for Bacillus subtilis 0.42, 0.27, and 0.474 mg/mL; and for Streptococcus pyogenes, 7.67, 3.86, and 8.5 mg/mL of pure RSALE, R-AuNPs, and Amoxicillin (control), respectively, incorporating that R-AuNPs have been shown to have a 1.4-fold, 2.1-fold, 1.5-fold, and 1.9-fold enhanced antibacterial activity in contrast to pure RSALE tested against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Streptococcus pyogenes, and Proteus vulgaris, respectively. Additionally, an enhanced antioxidant potential was detected in R-AuNPs compared to RSALE evaluated by the 2,2-Diphenyl-1-Picryl Hydrazyl Radical Scavenging (DPPH) Ferric reducing antioxidant power (FRAP) assay. The determined IC 50 values of RSALE and R-AuNPs were 0.131 ± 0.05 and 0.184 ± 0.02 mg/mL, and 0.110 ± 0.1 and 0.106 ± 0.24 mg/mL via the FRAP and DPPH assays, respectively. In addition, the anti-cancer activity against the human cervical cancer (Hela) cell line was evaluated, and the MTT assay results revealed that R-AuNPs (IC50 88.3 µg/mL) had an enhanced anti-cancer potential in contrast to RSALE (171.5 µg/mL). Subsequently, the findings of this study indicated that R. serpentina leaves and their nanoformulation can be used as a potent source for the treatment of the above-mentioned complications and can be used as a possible agent for novel target-based therapies for the management of different ailments. [ABSTRACT FROM AUTHOR]