2023, Editoriale in rivista, ENG
Quintieri, Laura; Koo, Ok Kyung; Caleb, Oluwafemi James
Frontiers in microbiology 142022, Articolo in rivista, ENG
Bonizzi, Serena; Gislon, Giulia; Brasca, Milena; Morandi, Stefano; Sandrucci, Anna; Zucali, Maddalena
Among factors that can affect calf health, microbial quality of the pen air is poorly studied. In 25 Italian dairy farms, data concerning air quality in the calf pens, hygiene of pens and equipment, microclimatic conditions, calf health and management were collected during the winter season (January-March 2020 and December-March 2021). The average air Standard Plate Count (SPC) of 85 pens was 4.51 (SD = 0.52) log cfu/m whereas the average air ammonia concentration was 0.66 (SD = 0.53) ppm. Positive correlations were found between average Temperature Humidity Index (THI) in the pen and air SPC, night maximum THI and air SPC and between SPC and yeast, mould and ammonia concentration in the pen air. The concentrations of E. coli, Enterobacteriaceae and yeasts in the pen air were higher and calf cough increased as the renewal interval of bedding material became longer. High bedding dry matter and low THI were associated with low air SPC, good calf health scores and low mortality. Maintaining low bedding humidity and controlling microclimatic conditions can contribute to enhancing air microbiological quality in the pen and reduce calf diseases and mortality.
DOI: 10.3390/ani12172286
2021, Articolo in rivista, ENG
Saab M.T.A.; Daou C.; Bashour I.; Maacaron A.; Fahed S.; Romanos D.; Khairallah Y.; Lebbous N.; Hajjar C.; Saad R.A.; Ojeil C.; Sellami M.H.; Roukoz S.; Salman M.
In the Bekaa Valley of Lebanon, the availability of freshwater is limited and therefore farmers must start using alternative water sources such as treated wastewater for irrigating crops. The present study is of great importance, since it provides evidence of some on-farm options that farmers can adopt when irrigating with treated effluent, in order to minimize the health risks. Eggplant was grown under two water quality regimes (Freshwater (FW) and treated wastewater (TW)) and two agronomic practices (no mulch (N_Mu) and use of plastic mulch (Mu)). Treatments were arranged in a split plot design with four replicates. Water quality regime was the main plot factor, while agronomic practices were the subplot factors. Water quality, soil, the marketable yield and other parameters were measured. Fruit samples were evaluated for bacterial contamination. The drip line performance was monitored. The study results revealed that the treatment with treated effluent gave more fruits.m, yield and mean fruit weight than the treatment using fresh water irrigation, with an increase of 3.98%, 10.74% and 5.63%, respectively. In addition, the use of mulch (Mu) resulted in an increase in yield (24.23%) and number of fruits (14.11%). Concerning the emitters' performance and sensitivity to clogging, discharge reduction rate (Rd = 6.75%) for drippers delivering TW was lower than the admissible value of 20% discharge variation, indicating that the quality of water has little effect on emitter performance. Concerning bacterial contamination of fruits, irrigation with treated wastewater showed no contamination in terms of fecal streptococci, salmonella or E. coli. However, the fruits were contaminated with fecal coliforms that were present at a concentration less than 200 CFU.100 g. Following the World Health Organization Guidelines, pathogens could be reduced through post treatment health-protection control measures such as drip irrigation, product washing, disinfection and produce peeling.
2021, Articolo in rivista, ENG
Sellitto V.M.; Zara S.; Fracchetti F.; Capozzi V.; Nardi T.
From a 'farm to fork' perspective, there are several phases in the production chain of fruits and vegetables in which undesired microbial contaminations can attack foodstuff. In managing these diseases, harvest is a crucial point for shifting the intervention criteria. While in preharvest, pest management consists of tailored agricultural practices, in postharvest, the contaminations are treated using specific (bio)technological approaches (physical, chemical, biological). Some issues connect the 'pre' and 'post', aligning some problems and possible solution. The colonisation of undesired microorganisms in preharvest can affect the postharvest quality, influencing crop production, yield and storage. Postharvest practices can 'amplify' the contamination, favouring microbial spread and provoking injures of the product, which can sustain microbial growth. In this context, microbial biocontrol is a biological strategy receiving increasing interest as sustainable innovation. Microbial-based biotools can find application both to control plant diseases and to reduce contaminations on the product, and therefore, can be considered biocontrol solutions in preharvest or in postharvest. Numerous microbial antagonists (fungi, yeasts and bacteria) can be used in the field and during storage, as reported by laboratory and industrial-scale studies. This review aims to examine the main microbial-based tools potentially representing sustainable bioprotective biotechnologies, focusing on the biotools that overtake the boundaries between pre-and postharvest applications protecting quality against microbial decay.
2020, Articolo in rivista, ENG
Frassinetti S.; Castagna A.; Santin M.; Pozzo L.; Baratto I.; Longo V.; Ranieri A.
To preserve quality and extend the shelf life of tomato, a bioactive edible coating was prepared using gelatin wastes from pharmaceutical industry and lyophilised blueberry juice (BJ). The effectiveness of gelatin-coating (G) and G enriched with blueberry juice (GB) was tested, monitoring carotenoids, polyphenols and flavonoids content, the antioxidant activity and the antimicrobial efficiency of coating against the native microflora. After 7 d of storage, coated fruit showed higher phenolic and flavonoids content and increased antioxidant activity, while carotenoids were unaffected by the treatments. The growth of mesophilic bacteria of GB, and the growth of coliform bacteria of G and GB were significantly reduced during the entire period. The results indicate that GB preserved the nutritional quality of tomatoes and that BJ was able to increase the antimicrobial activity of the coating. This paves the way for a possible use of this biodegradable waste polymer as an eco-friendly coating material.
2018, Articolo in rivista, ENG
Amalfitano S.; Levantesi C.; Garrelly L.; Giacosa D.; Bersani F.; Rossetti S.
During longer-lasting future space missions, water renewal by ground-loaded supplies will become increasingly expensive and unmanageable for months. Space exploration by self-sufficient spacecrafts is thus demanding the development of culture-independent microbiological methods for in-flight water monitoring to counteract possible contamination risks. In this study, we aimed at evaluating total microbial load data assessed by selected early-warning techniques with current or promising perspectives for space applications (i.e., HPC, ATP-metry, qPCR, flow cytometry), through the analysis of water sources with constitutively different contamination levels (i.e., chlorinated and unchlorinated tap waters, groundwaters, river waters, wastewaters). Using a data-driven double-threshold identification procedure, we presented new reference values of water quality based on the assessment of the total microbial load. Our approach is suitable to provide an immediate alert of microbial load peaks, thus enhancing the crew responsiveness in case of unexpected events due to water contamination and treatment failure. Finally, the backbone dataset could help in managing water quality and monitoring issues for both space and Earth-based applications.
2018, Articolo in rivista, ENG
Serra, S.; De Simeis, D.
AIMS: The preparation of the high-value flavour ?-dodecalactone is based on the biotransformation of natural 10-HSA, which is in turn obtained by microbial hydration of oleic acid. We want to establish a reliable baker's yeast-mediated procedure for 10-HSA preparation. METHODS AND RESULTS: The previously reported yeast-mediated hydration procedures are unreliable because bacteria-free baker's yeast is not able to hydrate oleic acid. The actual responsible for performing this reaction are the bacterial contaminants present in baker's yeast. Moreover, we demonstrated that the enantioselectivity in the production of (R)-10-HSA is affected mainly by the temperature used in the biotransformation. CONCLUSIONS: We demonstrated that Saccharomyces cerevisiae is not able to hydrate oleic acid, whereas different bacterial strains present in baker's yeast transform oleic acid into (R)-10-HSA. We reported a general procedure for the preparation of (R)-10-HSA starting from oleic acid and using commercially available baker's yeast. SIGNIFICANCE AND IMPACT OF THE STUDY: This study holds both scientific and industrial interest. It unambiguously establishes that the eukaryote micro-organisms present in baker's yeast are not able to hydrate oleic acid. The isolation of oleic acid hydrating bacterial strains from commercial baker's yeast points to their prospective use for the industrial synthesis of 10-HSA.
DOI: 10.1111/jam.13680
2018, Articolo in rivista, ENG
Piemontese, Luca; Messia, Maria Cristina; Marconi, Emanuele; Falasca, Luisa; Zivoli, Rosanna; Gambacorta, Lucia; Perrone, Giancarlo; Solfrizzo, Michele
Deoxynivalenol (DON) is an important mycotoxin produced by several species of Fusarium. It occurs often in wheat grain and is frequently associated with significant levels of its modified form DON-3-glucoside (DON-3-Glc). Ozone (O3) is a powerful disinfectant and oxidant, classified as GRAS (Generally Recognised As Safe), that reacts easily with specific compounds including the mycotoxins aflatoxins, ochratoxin A, trichothecenes and zearalenone. It degrades DON in aqueous solution and can be effective for decontamination of grain. This study reports the efficacy of gaseous ozone treatments in reducing DON, DON-3-Glc, bacteria, fungi and yeasts in naturally contaminated durum wheat. A prototype was used to dispense ozone continuously and homogeneously at different concentrations and exposure time, in 2kg aliquots of durum wheat. The optimal conditions, which do not affect chemical and rheological parameters of durum wheat, semolina and pasta, were identified (55g O3h-1 for 6h). The measured mean reductions of DON and DON-3-Glc in ozonated wheat were 29% and 44%, respectively. Ozonation also produced a significant (p<0.05) reduction of total count (CFU/g) of bacteria, fungi and yeasts in wheat grains.
2016, Articolo in rivista, ENG
Patanè C., Pellegrino A., Malvuccio A., Siracusa L., Ruberto G., Rizzo V., Giuffrida F.
The Mediterranean small-sized "long-storage" tomato, which allows an extended shelf life due to its textural properties, provides a delightful product that combines good taste with excellent nutritional properties. Due to the high drought tolerance of the plant, long-storage tomato is traditionally cultivated with no water supply once established, indicating an interesting genetic source in breeding programmes for water stress tolerance in both fresh and processing tomatoes. Recently, the feasibility of obtaining a new minimally processed product from local landraces of long-storage tomato has been considered. A study was conducted to assess the quality of fresh-cut long-storage tomato during storage at 4°C compared to a commercial cultivar of grape-shaped tomato, and also the efficacy of some dipping treatments on shelf-life extension. All fruits were disinfected for 10 min in a sodium hypochlorite solution before cutting in half. Dipping consisted of a 1 h dip in 1% citric acid or 2.4% calcium chloride solutions (w/v) after cutting. Long-storage tomato exhibited higher quality than commercial tomato throughout 13 days of storage, e.g. in terms of total solids (>8 g 100 g-1), total polyphenols (>0.12 mg g-1 fresh weight), soluble solids (>5 °Brix), and antioxidant activity [>80% 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition]. The calcium chloride dip resulted in greater cut fruit quality compared to the citric acid dip. Both treatments were beneficial for microbial quality (mesophiles, Enterobacteriaceae, lactic acid bacteria, yeasts and moulds) when compared to the control (distilled water dip), but not when compared to the untreated control (no dip), in which microbial load was the lowest.
2013, Articolo in rivista, ENG
Reale, A.; Di Renzo, T.; Succi, M.; Tremonte, P.; Coppola, R.; Sorrentino, E.
This study assessed the levels of microbial contaminants in liquid, compressed and dry commercial baker's yeasts used as starters in breadmaking. Eumycetes, Enterobacteriaceae, total and fecal coliforms, Bacillus spp., and lactic acid bacteria (LAB), in particular enterococci, were quantified. Results obtained in this study highlighted that baker's yeast could represent a potential vehicle of spoilage and undesirable microorganisms into the baking environment, even if these do not influence the leavening activity in the dough, as ascertained by rheofermentometer analysis. Different microbial groups, such as spore-forming bacteria and moulds, were found in baker's yeast starters. Moreover, different species of LAB, which are considered the main contaminants in large-scale yeast fermentations, were isolated and identified by Denaturing Gradient Gel Electrophoresis (DGGE) and 16S rDNA sequencing. The most recurrent species were Lactobacillus plantarum, Enterococcus faecalis, and Enterococcus durans, isolated from both compressed and dry starters, whereas strains belonging to Leuconostoc and Pediococcus genera were found only in dry ones. Nested-Polymerase Chain Reaction (Nested-PCR) and Randomly Amplified Polymorphic DNA-PCR (RAPD-PCR) were also used to highlight the biodiversity of the different commercial yeast strains, and to ascertain the culture purity.