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Nowadays, petroleum hydrocarbon pollution is one of the most widespread types of contamination that poses a serious threat to both public health and the environment. Among various physicochemical methods, bioremediation is an eco-friendly and cost-effective way to eliminate petroleum hydrocarbon pollutants. The successful degradation of all hydrocarbon components and the achievement of optimal efficiency are necessary for the success of this process. Using potential microbial consortia with rich metabolic networks is a promising strategy for addressing these challenges. Mixed microbial communities, comprising both fungi and bacteria, exhibit diverse synergistic mechanisms to degrade complex hydrocarbon contaminants, including the dissemination of bacteria by fungal hyphae, enhancement of enzyme and secondary metabolites production, and co-metabolism of pollutants. Compared to pure cultures or consortia of either fungi or bacteria, different studies have shown increased bioremediation of particular contaminants when combined fungal-bacterial treatments are applied. However, antagonistic interactions, like microbial competition, and the production of inhibitors or toxins can observed between members. Furthermore, optimizing environmental factors (pH, temperature, moisture, and initial contaminant concentration) is essential for consortium performance. With the advancements in synthetic biology and gene editing tools, it is now feasible to design stable and robust artificial microbial consortia systems. This review presents an overview of using microbial communities for the removal of petroleum pollutants by focusing on microbial degradation pathways, and their interactions. It also highlights the new strategies for constructing optimal microbial consortia, as well as the challenges currently faced and future perspectives of applying fungal-bacterial communities for bioremediation.
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Bactérias , Biodegradação Ambiental , Fungos , Hidrocarbonetos , Consórcios Microbianos , Petróleo , Poluentes do Solo , Bactérias/metabolismo , Fungos/metabolismo , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Poluição por Petróleo , Poluentes do Solo/metabolismoRESUMO
Metabolic by-products are part of the so-called postbiotics of probiotics and other beneficial microorganisms, particularly lactic acid bacteria, which have gained popularity as a feasible alternative to improving food quality and safety. Postbiotics in dry and liquid forms can be easily integrated into food formulations and packaging materials, exhibiting antimicrobial and antioxidant effects owing to the presence of multiple antimicrobials, such as organic acids, bacteriocins, exopolysaccharides and bioactive peptides. Postbiotics can thus control the growth of pathogens and spoilage microorganisms, thereby extending the shelf life of food products. Because of their ability to be easily manufactured without requiring extensive processing, postbiotics are regarded as a safer and more sustainable alternative to synthetic preservatives, which can have negative environmental consequences. Additionally, food manufacturers can readily adopt postbiotics in food formulations without significant modifications. This systematic review provides an in-depth analysis of studies on the use of postbiotics in the biopreservation and packaging of a wide range of food products. The review evaluates and discusses the types of microorganisms, postbiotics preparation and modification techniques, methods of usage in dairy products, meat, poultry, seafood, fruits, vegetables, bread, and egg, and their effects on food quality and safety.
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BACKGROUND: Nurses working in neonatal intensive care units play a crucial role in providing care to critically ill or premature neonates. However, is not without its challenges, particularly when it comes to making difficult ethical decisions about end-of-life care. In some cases, neonates do not survive despite the best efforts of medical professionals. The present study aimed to investigate the relationship between moral distress, ethical climate, and attitudes towards end-of-life care among nurses working in neonatal intensive care units. METHODS: This is a descriptive-analytical cross-sectional study (May 21, 2021).The research population included 126 nurses working in neonatal intensive care units in Kerman province (Kerman, Jiroft, Bam, and Rafsanjan). Data collection tools included four questionnaires: demographic information, the Frommelt Attitudes towards Care of the Dying (FATCOD), the Hospital Ethical Climate Survey, and the Moral Distress Scale. SPSS22 was used to analyze the data. RESULTS: The results revealed that the mean frequency and intensity of moral distress were 44.42 ± 17.67 and 49.45 ± 17.11, respectively. The mean ethical climate was 92.21 ± 17.52 and the FATCOD was 89.75 ± 9.08, indicating NICU nurses' positive perceptions of ethical climate and their favorable attitudes towards EOL care, respectively. The results showed a direct and significant relationship between ethical climate and the FATCOD (P = 0.003, r = 0.26). DISCUSSION: We suggest policymakers and managers design strategies for better ethical climate in hospitals and reduction of moral distress among nurses.
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Breast milk (BM) is considered as the best source of nutrition which could have prevention effects on various diseases in the first years of a child. Along with nutritive compounds, presence of contaminants such as mycotoxins in BM could be transmitted into neonate. The aim of this study was to determine the occurrence, levels, and factors associated with the presence of aflatoxin M1 (AFM1) and ocratoxin a (OTA) in BM samples of nursing mothers in rural centers of Yazd, Iran. The presence and average AFM1 and OTA concentration in 72 BM samples was measured by competitive ELISA. The demographic and diet parameters of nursing mothers were collected by a questionnaire and were analyzed using SPSS 18 software. AFM1 and OTA were detected in 63 (87.5%) and 47 (65.2%) samples with the mean concentration levels of 19.46 ± 13.26 ng/L (ranges from 5.1 to 53.9) and 200 ± 160 ng/L (ranges from 100 to 2460), respectively. Of these, 32 samples (50.7%) for AFM1 and 23 samples (48.9%) for OTA had values exceeding the limit set by the European Union regulation for infant foods (25 ng/L for AFM1 and 500 ng/L for OTA). It was also found that the risk of AFM1 and OTA occurrence in BM increased significantly with the consumption of beans, bread, cereals, fruit juice and crackers, and cream, respectively. This study showed that the estimated daily intake for AFM1 and OTA by 1 month of age infants was 2.7 and 28.5 ng/kg bw/day, respectively, while, as the age of the infant increased, the values were lower and close to 0.9 and 9.9 ng/kg bw/day for AFM1 and OTA in 12 months of age infants, respectively. The high occurrence and noticeable levels of AFM1 and OTA detected in this study indicated that some infants receive undesirable exposures to AFM1 and OTA with breast milk. Therefore, it is recommended that mothers are advised to avoid certain foods during pregnancy and breastfeeding that are likely sources of mycotoxins.
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Aflatoxina M1 , Leite Humano , Ocratoxinas , População Rural , Aflatoxina M1/análise , Humanos , Irã (Geográfico) , Ocratoxinas/análise , Feminino , Adulto , Leite Humano/química , Medição de Risco , Adulto Jovem , Contaminação de Alimentos/análise , Lactente , Ensaio de Imunoadsorção EnzimáticaRESUMO
A colorimetric assay method is described for the environmental detection of 2-mercaptobenzimidazole (MBI) using surface plasmon resonance of gold nanoparticles (AuNPs). Stable and dispersed AuNPs with intensified plasmon resonance were prepared in situ using a simple, rapid, and eco-friendly procedure by applying ascorbic acid as a reducer and cetyltrimethylammonium bromide as a stabilizer. The presence of MBI has a strong effect on the plasmon absorbance of AuNPs, which was employed for the detection of MBI. The calibration curve was linear in the range of 1.0 × 10(-6)-5.5 × 10(-5) mol/L of MBI; the detection limit was 8.4 × 10(-7) mol/L. The relative standard deviations for eight replicate measurements of 3.0 × 10(-6) and 5 × 10(-5) mol/L MBI were 3.9 and 1.4%, respectively. The method was successfully applied to the determination of MBI in tap, river, sea, and heat exchanger cooling water samples.
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Benzimidazóis/análise , Monitoramento Ambiental/métodos , Ouro/química , Nanopartículas Metálicas/química , Ressonância de Plasmônio de Superfície/métodos , Fracionamento Químico/métodos , Colorimetria , Limite de DetecçãoRESUMO
Biofilm is considered as a community of microorganisms in which cells adhere to each other on surfaces in a self-produced matrix of extracellular polymer compounds. In recent years, efforts to use the beneficial aspects of biofilm in probiotic research have intensified. In this study, probiotic biofilms of Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus were manufactured using milk and transferred to yogurt in whole and pulverized forms to test in real food conditions. Survival was assessed during 21 days of storage time as well as gastrointestinal conditions. The results indicated that Lp. plantarum and Lc. rhamnosus can form a very desirable and strong biofilm that can have a good protective effect on the survival of these bacteria in probiotic yogurt during processing, storage, and gastrointestinal conditions, in a way that, after 120 min of treatment in high acidic gastrointestinal conditions (pH 2.0), the survival rate decreased by only 0.5 and 1.1 log CFU/ml. Probiotic biofilm can be used as a natural way of utilizing bacteria in biotechnology and fermentation, which is an excellent way to increase the utility of probiotics.
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The food industry has always sought to produce products enriched with vitamins, probiotics, polyphenols, and other bioactive compounds to improve physiological function, enhance nutritional value, and provide health. These compounds are essential for human health, and their deficiency can lead to adverse effects. Therefore, food enrichment is an important strategy to improve the nutritional value and, in some cases, improve the quality of food. Recently, functional foods have been very popular around the world. Among food products, dairy products constitute a major part of people's diet, and due to the high consumption of dairy products, including yogurt, the enrichment of this product effectively reduces or prevents diseases associated with nutritional deficiencies. Most consumers generally accept yogurt due to its high nutritional value and low price. So, it can be considered a good candidate for enrichment with micronutrients and probiotics. In recent years, using functional foods to prevent various diseases has become a popular topic for research. In this study, the effect of fortified yogurt in preventing diseases and improving deficiencies has been investigated, and it has been proven that super healthy yogurt has a positive effect on human health.
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Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Probióticos , Humanos , Iogurte , Vitaminas , Nível de SaúdeRESUMO
Essential oils (EOs) are natural products called volatile oils or aromatic and ethereal oils derived from various parts of plants. They possess antioxidant and antimicrobial properties, which offer natural protection against a variety of pathogens and spoilage microorganisms. Studies conducted in the last decade have demonstrated the unique applications of these compounds in the fields of the food industry, agriculture, and skin health. This systematic article provides a summary of recent data pertaining to the effectiveness of EOs and their constituents in combating fungal pathogens through diverse mechanisms. Antifungal investigations involving EOs were conducted on multiple academic platforms, including Google Scholar, Science Direct, Elsevier, Springer, Scopus, and PubMed, spanning from April 2000 to October 2023. Various combinations of keywords, such as "essential oil," "volatile oils," "antifungal," and "Aspergillus species," were used in the search. Numerous essential oils have demonstrated both in vitro and in vivo antifungal activity against different species of Aspergillus, including A. niger, A. flavus, A. parasiticus, A. fumigatus, and A. ochraceus. They have also exhibited efficacy against other fungal species, such as Penicillium species, Cladosporium, and Alternaria. The findings of this study offer novel insights into inhibitory pathways and suggest the potential of essential oils as promising agents with antifungal and anti-mycotoxigenic properties. These properties could make them viable alternatives to conventional preservatives, thereby enhancing the shelf life of various food products.
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Background and Objectives: Phage therapy has gained interest as an alternative treatment for methicillin-resistant Staphylococcus aureus (MRSA) infections. The purpose of this study was to isolate and characterize an effective bacteriophage against isolates of MRSA. Materials and Methods: Bacteriophage was isolated from hospital sewage. Lytic activity and the titers of phage lysates were measured using spot test and double-layer plaque assay. The phage characterization was determined through transmission electron microscopy. Adsorption rate, host range and stability tests were investigated. The latent period and burst size were estimated from a one-step growth curve. The effect of bacteriophage against MRSA biofilms was determined and Real-time PCR was used to assess the effects of the bacteriophage on the expression of the biofilm-associated genes. Results: TEM results showed that the phage resembled the Cystoviridae family. Its latent period was 30 min, corresponding to about 71/43 phage particles per infected cell. The phage had a broad host range and it was most stable at 37°C and pH 7. It was sensitive to NaCl concentrations. The expressions of the biofilm-associated genes were significantly reduced in the presence of the phage. Conclusion: The isolated phage was effective against MRSA strains and it can be an optional strategy of controlling biofilm development.
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Currently, the health benefits of probiotic bacteria are well known, and this has taken up a great deal of space in food science and health, both research and operational. On the other hand, anti-biofilm properties on food pathogens in the food and pharmaceutical industries have created an attractive challenge. This study aimed to describe the inhibitory activity of cell-free supernatants (CFS), planktonic cells, and biofilm form of lactobacilus strains (L. rhamnosus and L. plantarum) against food pathogens such as Pseudomonas aeruginosa and Listeria monocytogenes. Anti-bacterial activities of the CFS of lactobacillus strains were assessed by the microplate method and via violet staining. Evaluation of the antagonistic activity of planktonic cells and biofilm of LAB were performed by the spread plate method. The results showed the incubation time of 48 h was the best time to produce biofilm. Although the planktonic states reduce the pathogens bacterial about 1 -1.5 log, but in biofilm forms, decreased L. monocytogenes about 4.5 log compared to the control, and in the case of P. aeruginosa, a growth reduction of about 2.13 log was observed. Furthermore, biofilm formation of L. monocytogenes in the presence of L. rhamnosus cell-free supernatant was more weakly than L. plantarum CFS, but their CFS effect on reducing the bacterial population of P. aeruginosa was the same. According to the study, biofilm produced by probiotic strains can be considered a new approach for biological control. Also, cell-free supernatant can be used as postbiotic in the food and pharmaceutical industries.
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BACKGROUND: Since December 2019, the world has been facing one of the most critical health threats of the last decades. In March 2021, the official number of deaths passed 2.6 million worldwide. Most countries have developed policies to control the disease. Nevertheless, countries have experienced different outcomes related to their various adapted policies. Complementing our first report, in this article, we report our findings of comparing the policies adopted to combat coronavirus disease 2019 (COVID-19) in Iran, with those from nine selected countries, including China, Japan, South Korea, Singapore, Germany, the United States, the United Kingdom, Spain, and Italy, to draw evidence-informed policy lessons. METHODS: This is a qualitative study conducted based on document analysis related to COVID-19 policies in Iran and nine selected countries. Using a deductive approach, data were extracted and analyzed based on the components of the WHO Building Blocks Framework. Finally, we compared the Iranian policies with the nine selected countries. RESULTS: Documents analysis revealed a spectrum of policies, which have led to a variety of outcomes. Based on our findings, three main strategies (widespread testing, comprehensive contact tracing, and timely measures) were the most effective directions to combat COVID-19. CONCLUSION: The experience of the first and second waves of COVID-19 showed that the risk of coronavirus is serious and will continue until a vaccine or decisive treatment is achieved. Therefore, countries are required to adopt appropriate and tailored policies to deal with this crisis effectively. Applying the experiences from the previous waves is essential for more efficient performance in the likely upcoming waves.