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Meat products contain valuable nutrients that are important for human health and development but are also highly susceptible to colonization by microorganisms. This can lead to spoilage and serious foodborne illnesses. Natural antimicrobial peptides, produced by many organisms as part of their innate immune system to fight microbial infections, have great potential as food preservatives. In this study, we explored the effect of ternary antimicrobial random peptide mixtures (RPMs) on food spoilage bacteria in minced turkey meat. Amendment of RPMs to meat led to significant reductions in bacterial abundance in experimental tests, and RPMs worked synergistically with nitrite to reduce bacterial loads. Using high-throughput 16S ribosomal RNA gene amplicon sequencing, we characterized the effect of RPMs and nitrite on meat microbial community structure before and during incubation under refrigerated conditions. Our findings reveal strong antimicrobial activity for RPMs against spoilage bacteria in meat, including Listeria monocytogenes and Pseudomonas putida. These results demonstrate the potential of RPMs as a safer preservative for reducing spoilage in meat and other food products., (Copyright © 2020. Published by Elsevier Ltd.)

We developed, validated, and confirmed with proficiency tests a fast ultra-high-performance liquid chromatography with diode array detector (UHPLC-DAD) method to determine histamine in fish and fishery products. The proposed method consists of two successive solid-liquid extractions: one with a dilute solution of perchloric acid (6%) and the second only with water. The instrumental analysis with UHPLC provides a very fast run time (only 6 min) with a retention time of approximately 4 min, a limit of quantification (LOQ) of 7.2 mg kg -1 , a limit of detection (LOD) of 2.2 mg kg -1 , a recovery around 100%, a relative standard deviation (RSD%) between 0.5 and 1.4, and an r 2 of calibration curve equal to 0.9995. The method detected optimal values of the validation parameters and required a limited number of reagents in comparison to other methods reported in the literature. Furthermore, the method could detect histamine in a very short time compared with other methods. This method, in addition to being validated, precise, specific, and accurate, avoids wasting time, money, and resources, and limits the use of organic solvents.

Abstract: In total, 4,615 fresh and processed fish samples collected from 2010 to 2015 were analyzed for histamine by ultrahigh-performance liquid chromatography with diode array detection. Histamine levels were detected in 352 (7.6%) samples, with a maximum of 4,110 mg kg-1 and mean values of 908.9 ± 1,226.79 and 344.01 ± 451.18 mg kg-1 for fresh and processed fish samples, respectively. No histamine levels were found in canned tuna and smoked fish samples in contrast to most of the data reported in the literature. A low percentage (2.79%) of noncompliant samples was found. The highest mean values were found during 2011 and 2015 for fresh and processed fish samples, respectively, showing a significant (P < 0.05) difference between the sampling years. The histamine contents found in fresh fish samples were significantly higher (P < 0.05) than those of processed samples. Most of the positive samples came from street vendors, suggesting the need to improve inspection measures in these commercial categories to ensure fish product safety., (Copyright ©, International Association for Food Protection.)

Parasites belonging to the Anisakis genera are organisms of interest for human health because they are responsible for the Anisakiasis zoonosis, caused by the ingestion of raw or undercooked fish. Furthermore, several authors have reported this parasite to be a relevant inducer of acute or chronic allergic diseases. In this work, a rapid commercial system based on Loop-Mediated Isothermal Amplification (LAMP) was optimised and validated for the sensitive and rapid detection of Anisakis spp. DNA in processed fish products. The specificity and sensitivity of the LAMP assay for processed fish samples experimentally infected with Anisakis spp. larvae and DNA were determined. The LAMP system proposed in this study was able to give positive amplification for all the processed fish samples artificially contaminated with Anisakis spp., giving sensitivity values equal to 100%. Specificity tests provided no amplification for the Contracaecum , Pseudoterranova , or Hysterothylacium genera and uninfected samples. The limit of detection (LOD) of the LAMP assay proposed was 10 2 times lower than the real-time PCR method compared. To the best of our knowledge, this is the first report regarding the application of the LAMP assay for the detection of Anisakis spp. in processed fish products. The results obtained indicate that the LAMP assay validated in this work could be a reliable, easy-to-use, and convenient tool for the rapid detection of Anisakis DNA in fish product inspection.

Microorganisms represent most of the biodiversity of living organisms in every ecological habitat. They have profound effects on the functioning of any ecosystem, and therefore on the health of our planet and of human beings. Moreover, microorganisms are the main protagonists in food, medical and biotech industries, and have several environmental applications. Accordingly, the characterization and preservation of microbial biodiversity are essential not only for the maintenance of natural ecosystems but also for research purposes and biotechnological exploitation. In this context, culture collections (CCs) and microbial biological resource centres (mBRCs) are crucial for the safeguarding and circulation of biological resources, as well as for the progress of life sciences. This review deals with the expertise and services of CCs, in particular concerning preservation and characterization of microbial resources, by pointing to the advanced approaches applied to investigate a huge reservoir of microorganisms. Data sharing and web services as well as the tight interconnection between CCs and the biotechnological industry are highlighted. In addition, guidelines and regulations related to quality management systems (QMSs), biosafety and biosecurity issues are discussed according to the perspectives of CCs and mBRCs.

The fatty acid (FA) profile of wild Theba pisana , Cornu aspersum , and Eobania vermiculata land snail samples, collected in Sicily (Southern Italy), before and after heat treatment at +100 °C were examined by gas chromatography with a flame ionization detector (GC-FID). The results show a higher content of polyunsaturated fatty acids (PUFAs) in all of the examined raw snails samples, representing up to 48.10% of the total fatty acids contents, followed by monounsaturated fatty acids (MUFAs). The thermal processing of the snail samples examined determined an overall reduction of PUFA levels (8.13%, 7.75%, and 4.62% for T. pisana , C. aspersum and E. vermiculata samples, respectively) and a species-specific variation of saturated fatty acid (SFA) contents. Oleic acid remained the most abundant FA of all of the snails species examined, accounting for up to 29.95% of the total FA content. A relevant decrease of ɷ3/ɷ6 ratio was found only for T. pisana samples. The principal component analysis (PCA) showed a separation of the snail samples in terms of species and heat treatment. The results of this work suggest land snails as a valuable source of MUFA and PUFA contents and boiling as appropriate treatment, according to the maintenance of healthy properties., Competing Interests: The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

The Black Soldier Fly (Hermetia illucens (L.), Diptera: Stratiomyidae) is an insect whose larvae thrive on agro-industrial by-products. This study reports the first use of black soldier fly larvae processing residue (BSPR) as an innovative ingredient for growing media. BSPR was characterized and evaluated to partially replace commercial peat (CP) in the production of potted plants. Chemical and microbiological analysis showed the suitability of BSPR for soilless production. Hence, six growing media mixtures (CP 100% + slow acting synthetic solid fertilizer, CP 90% + BSPR 10%, CP 80% + BSPR 20%, CP 70% + BSPR 30%, CP 60% + BSPR 40% and CP 100% without fertilizer) were assessed for the production of baby leaf lettuce, basil and tomato potted plants. Using BSPR in a proportion up to 20%, all investigated crops showed values significantly greater than or comparable to those obtained using CP 100% + slow acting synthetic solid fertilizer. In general, BSPR used in a proportion up to 20% increased the crop growth of baby leaf lettuce, basil and tomato, recording a high total dry weight (+31%, compared to the total average) and the measured leaf parameters (+39% of leaf area, +14% of leaf number), without showing abiotic stresses. This study indicates that BSPR used in a proportion up to 20% might be a valid approach for soilless production of potted baby leaf lettuce, basil and tomato plants., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

We examined a total of 369 bovine liver and muscle samples for the detection of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC), and doxycycline (DOX) residues by implementation and validation of a LC-MS/MS method. The method showed good recovery values between 86% and 92% at three levels of concentrations. The linearity tests revealed r² > 0.996 for all the tetracyclines examined. Furthermore, the Youden test revealed that the method was robust. Only 14.4% of the samples showed OTC and TC residues in a concentration range of 10.4⁻40.2 µg kg -1 . No CTC and DOX residues were found in all the samples analyzed. Liver samples showed the highest average values (31.5 ± 20.6 and 21.8 ± 18.9 for OTC and TC, respectively). The results showed a low incidence of TCs in all the samples examined, in comparison with other studies reported in the literature. A significant decrease in TC residues frequency was found from 2013 ( p < 0.05). This work reports for the first time epidemiological data on the presence of TC residues in liver and muscle samples of cattle farmed in Sicily (Southern Italy). The very low incidence of TC residues indicates a continuous improvement in farming techniques in Southern Italy, which is essential to ensure consumers' protection.

Samples (n = 485) of raw (n = 394) or heat-treated (n = 91) milk of three different species (cow, n = 170; sheep, n = 133; donkey, n = 84), collected 2013-2016 in Western Sicily (Southern Italy), were analyzed for aflatoxin M 1 (AFM 1 ) by enzyme-linked immunosorbent assay (ELISA). Positive ELISA results were further analyzed by HPLC with fluorescence detection. Both methods had a detection limit for AFM 1 in milk of 7 ng kg -1 . ELISA yielded 12.9 and 5% positives in cows and sheep milk, respectively, all samples of donkey milk were negative. Levels of AFM 1 were in most cases at 0.007-< 0.05 μg kg -1 , only two samples (sheep milk) slightly exceeded the European Union maximum level of 0.05 μg kg -1 . Only 6% of the samples were positive for AFM 1 in a concentration range of 0.008-0.15 μg kg -1 . Only milk samples collected directly from farms were positive. Overall, the levels were much lower than previously reported for Southern Italy cow and sheep milk samples purchased in retail stores. The results of this work indicate a continuous improvement of the feeding techniques on dairy farms of Southern Italy, which is essential to ensure consumers' protection.

The crossing of Saccharomyces strains by spore conjugation is one of the ways to obtain new starter cultures for the fermentation industry. One of the major difficulties of this practice is the identification of the newly formed hybrids. In this work we describe an effective molecular method for the validation of Saccharomyces intraspecific crosses. The method described is based in the hypothesis that hybrids constructed by spore conjugation contain the sum of the genomes of both parental strains. As a consequence, the conjugation of spores of two yeasts showing different genomic fingerprinting profiles will result in a hybrid culture that will show the sum of both profiles. We demonstrated that the detection of polymorphism in two genes containing minisatellite-like sequences, either SED1 or AGA1, is suitable for this purpose. Using this strategy we were able to validate 15 crosses out of 162 hybridization attempts.

We propose an efficient and time-saving strategy for starter culture selection. Our approach is based on the accomplishment of 3 phases: (i) the selection of yeast strains dominating spontaneous fermentations, (ii) the selection among the dominant strains of those showing the best technological characteristics, and (iii) the final selection among good technological strains of those showing the desired qualitative traits. We applied this approach to wine fermentations, even though the same strategy has the potential to be employed for the selection of any type of starter culture. We isolated and identified yeast strains at the mid- and final stages of 6 spontaneous fermentations carried out in 3 different Spanish wineries. We identified all strains as Saccharomyces cerevisiae by restriction fragment length polymorphism of the ribosomal DNA internal transcribed spacer region, and subsequently distinguished each strain by analyzing the polymorphism of the inter-delta regions. Strains that were detected both at the mid- and final stages of the fermentation were considered dominant. Four dominant strains were finally selected and tested in pilot-scale fermentation, and their performance was compared with that of a commercial wine strain. All dominant strains showed good fitness and resulted suitable to be employed as starter cultures. One of the dominant strains isolated in this study is currently commercialized.

Purpose: To assess the feasibility of percutaneous transhepatic biliary drainage (PTBD) for the treatment of postsurgical biliary leaks in patients with nondilated intrahepatic bile ducts, its efficacy in restoring the integrity of bile ducts, and technical procedures to reduce morbidity., Methods: Seventeen patients out of 936 undergoing PTBD over a 20-year period had a noncholestatic liver and were retrospectively reviewed. All patients underwent surgery for cancer and suffered a postsurgical biliary leak of 345 ml/day on average; 71% were in poor condition and required permanent nutritional support. An endoscopic approach failed or was excluded due to inaccessibility of the bile ducts., Results: Established biliary leaks and site of origin were diagnosed an average of 21 days (range 1-90 days) after surgery. In all cases percutaneous access to the biliary tree was achieved. An external (preleakage) drain was applied in 7 cases, 9 patients had an external-internal fistula bridging catheter, and 1 patient had a percutaneous hepatogastrostomy. Fistulas healed in an average of 31 days (range 3-118 days ) in 15 of 17 patients (88%) following PTBD. No major complications occurred after drainage. Post-PTBD cholangitis was observed in 6 of 17 patients (35%) and was related to biliary sludge formation occurring mostly when drainage lasted >30 days and was of the external-internal type. Median patient survival was 17.7 months and in all cases the repaired biliary leaks remained healed., Conclusions: PTBD is a feasible, effective, and safe procedure for the treatment of postsurgical biliary leaks. It is therefore a reliable alternative to surgical repair, which entails longer hospitalization and higher costs.

Different molecular techniques were tested to determine which was the most effective in the identification of Saccharomyces cerevisiae strains. In particular, polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP) analysis of the internal transcribed spacer (ITS) regions and the nontranscribed spacer 2 (NTS2) region, sequencing of the D1/D2 domain, and electrophoretic karyotyping were applied to 123 yeast strains isolated from different sourdoughs and tentatively attributed to the species S. cerevisiae. All of the strains tested showed an identical PCR-RFLP pattern for the ITS regions, an identical nucleotide sequence of the D1/D2 domain, and the typical electrophoretic karyo type of S. cerevisiae. In contrast, 14 out of the 123 strains tested showed some polymorphism with BanI restriction analysis of the NTS2 region. Our results indicate that while the sequencing of the D1/D2 domain, the PCR-RFLP analysis of the ITS regions, and the electrophoretic karyotype can be employed successfully to identify S. cerevisiae strains, PCR-RFLP analysis of the NTS2 region does not allow a consistent and accurate grouping for S. cerevisiae strains. The fact that the NTS2 region of a small number of strains (8.78% of the total strains tested) is different from that of the other S. cerevisiae strains confirms that molecular methods should always be tested on a great number of strains.

The combination of lamivudine and hepatitis B immunoglobulin (HBIG) reduces the risk of hepatitis B virus (HBV) recurrence after liver transplantation (LT). However, the efficacy of this strategy and the need for combined therapy with adefovir dipivoxil (ADV) in patients who select lamivudine-resistant strains (YMDD) before surgery is still unknown. Twenty-two patients treated with lamivudine (LAM) who underwent LT after YMDD-mutant selection were studied. In 13 patients, YMDD mutants were associated with an HBV DNA breakthrough greater than 5 log10 (group A: phenotypic resistance), and 11 were treated with ADV to decrease viral load before LT. In the remaining 9 patients who did not experience the viral breakthrough, YMDD mutants were detected only retrospectively in sera stored at the time of LT (group B: genotypic resistance). During 35 months of post-LT follow-up, none of the 11 patients of group A treated with ADV before and after surgery (in addition to HBIG and LAM) had HBV recurrence, and neither did any of the 7 subjects of group B treated with LAM before and after transplantation (in addition to HBIG). HBV recurred in 2 patients of group A (untreated with ADV before surgery and transplanted with an HBV DNA exceeding 5 log10) and in 2 subjects of group B (who spontaneously stopped HBIG after surgery). In carriers of YMDD mutants, the risk of post-LT HBV recurrence is low, provided that preemptive and prophylactic ADV (in addition to LAM and HBIG) treatment is used in highly viremic patients and prophylactic LAM (or ADV) and HBIG therapy is continued in low viremic patients.

Recent developments in expression profile and proteomic techniques illustrated that the main oenological traits of wine yeasts are complex and influenced by several genes, each of them identified as absolutely essential. Only for monogenic properties the genetic improvement programmes of wine yeasts can be performed by alteration of individual genes. Ideally the most productive way of improving the whole-cell biocatalysts is by evolution of the entire cell genome. In this article we briefly review the main genetic improvement techniques applied in new and optimised wine strains construction, paying particular attention to blind and whole genome strategies, such as the sexual recombination and genome shuffling.

Background: Hypermetabolism, insulin resistance, and diabetes are common in patients with liver cirrhosis., Objective: We assessed whether diabetes and insulin resistance influence postabsorptive energy homeostasis in these patients and whether liver transplantation (LTx) and immunosuppressive drugs affect these relations., Design: Twenty-six patients with liver cirrhosis (16 with and 10 without diabetes) were studied with an insulin clamp and indirect calorimetry. Eleven of these subjects were studied 9 mo after LTx to longitudinally assess its effects. To cross-sectionally explore a longer follow-up period, we studied 65 patients 6, 14, and 32 mo after LTx. Seven patients with chronic uveitis (receiving immunosuppressive therapy) and 20 healthy subjects served as control subjects., Results: Diabetic and nondiabetic patients with cirrhosis had insulin resistance (S(I(clamp)); P < 0.03) and higher measured resting energy expenditure (REE) as a percentage of predicted REE than did healthy subjects (107.6 +/- 1.8% compared with 97.4 +/- 2.3%; P < 0.03), and these 2 alterations were associated (R(2) = 0.119, P = 0.0002). The longitudinal study showed an improvement in the 2 variables after LTx, but full restoration was not achieved. The cross-sectional analysis confirmed this observation in patients studied 6 mo (n = 28) after LTx. In patients studied 14 (n = 21) and 32 mo (n = 16) after LTx, S(I(clamp)) and measured REE as a percentage of predicted REE were not significantly different from those in control subjects., Conclusions: In patients with liver cirrhosis, higher-than-normal postabsorptive REE was associated with insulin resistance regardless of diabetes. This abnormality persisted in patients studied 6-9 mo after LTx but improved simultaneously with the improvement in insulin sensitivity thereafter.