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In this paper, a fault diagnosis method for the basic process of microbial growth in wastewater treatment based on interval estimation technology is proposed. First, a nonlinear microbial growth model is converted into a linear time‐varying system. A time‐varying observer is then designed for the generated system, which takes into account an L∞$$ {L}_{\infty } $$ performance. Furthermore, a zonotope‐based set‐membership estimation algorithm is analyzed to synchronize interval estimation operations. In addition, interval residuals are computed from the generated interval state estimation and fault diagnosis is performed for a wastewater treatment bioprocess with sensor fault signals. Finally, the feasibility of the proposed fault diagnosis strategy for the wastewater treatment bioprocess is illustrated through numerical simulations. [ABSTRACT FROM AUTHOR]

This study investigated the potential use of curcumin‐mediated photodynamic treatment as a postharvest decontamination technique to reduce microbial load and growth and therefore extend the shelf life of strawberries. Curcumin was applied on strawberries, followed by illumination and storage at 4°C for 16 days. Strawberries were evaluated for decay, microbial load, and physicochemical properties such as weight loss, color, and firmness during storage. The findings revealed that curcumin‐mediated photodynamic treatment effectively reduced the decay incidence and severity in strawberries, with 20% less decay occurrence compared to untreated fruits, which was shown to be dependent on curcumin concentration. While a complete reduction in microbial load was observed upon treatment, microbial growth remained unaffected throughout storage. Moreover, photodynamic treatment did not show any adverse impact on color properties and firmness of strawberries. This eco‐friendly technique presents potential for fruit's shelf‐life extension, although optimization of treatment parameters and photodynamic unit design seems to be essential. [ABSTRACT FROM AUTHOR]

Microbial spoilage is a major cause of degradation of the quality characteristics of products, such as meat and dairy products or fruits and vegetables. There is a need for eco-friendly practices that prevent microbial growth, while preserving the nutritional value of these products during processing and transportation to the consumer. Traditional food preservation methods, being thermal or chemical techniques, often have a negative impact on the sensory, quality and textural characteristics of the food product. Ozonation is of interest for the food industry using the antimicrobial properties of ozone. It is important for various food products to control the oxidation of lipids. The effects of ozone treatment on lipid oxidation in foods are evaluated in this review. The mechanisms of lipid ozone oxidation are discussed, and the results of different studies are analyzed. It also examines the factors that can affect the efficacy of ozone treatment and the possible risks associated with this technology. Ozone treatment prolongs shelf life, while maintaining product quality and is cost-effective in terms of energy use. It has been shown to inhibit the formation of volatile compounds in some food products, and reduce the occurrence of reactions that reduce the overall quality characteristics of the food, such as lipid oxidation. The effect of ozone application on quality varies with the structure of the food, ozone application time and dose amount. [ABSTRACT FROM AUTHOR]

Summary: This study aimed to investigate the antioxidant and protease activities of red kiwifruit (RK), green kiwifruit (GRK), and gold kiwifruit (GOK) and determine the effects of various packaging methods on the quality of chicken breast injected with various kiwifruit types during storage. The physicochemical and textural properties of chicken breasts containing various kiwifruit types were evaluated. Chicken breasts were injected with brine solution containing 5% kiwifruit powder, and their product quality was measured every 3 days until day 9. GOK and RK addition to chicken breast delayed oxidation during storage. Adding GOK and GRK to chicken breast was found to increase tenderness. Modified‐atmosphere packaging (MAP) delayed microbial growth more effectively than over‐wrap packaging (OWP). These findings suggest that the combination of GOK and MAP potentially extends shelf‐life without deteriorating quality. [ABSTRACT FROM AUTHOR]

Fresh food are consumed in large quantities worldwide. During the supply chain, microbial growth in fresh food can lead to the production of a number of metabolites, which make food highly susceptible to spoilage and contamination. The quality of fresh food changes in terms of smell, tenderness, color and texture, which causes a decrease in freshness and consumers acceptance. Therefore, the quality monitoring of fresh food has become an essential part in the supply chain. As traditional analysis methods are highly specialized, expensive and have a small scope of application, which cannot be applied to the supply chain to realize real-time monitoring. Recently, sensing materials have received a lot of attention from researchers due to the low price, high sensitivity and high speed. However, the progress of research on sensing materials has not been critically evaluated. The study examines the progress of research in the application of sensing materials for fresh food quality monitoring. Meanwhile, indicator compounds for spoilage of fresh food are analyzed. Moreover, some suggestions for future research directions are given. [ABSTRACT FROM AUTHOR]

In this paper, the application of inactivation by plasma-activated water (PAW) for exporting whiteleg shrimp and splendid squid is studied. Through experimentation, the maximum hydrogen peroxide (H2O2) concentration in PAW was determined by utilizing a full factorial design with two-level factors. Subsequently, analysis of variance (ANOVA) was conducted using Minitab. The results indicated that a gas flow rate of a mixture of Ar (98%) and O2 (2%) at 25 L/min and a discharge time of 120 min generated the optimal concentration of H2O2 in PAW (13.30 mg/L), as per the response optimizer. The use of PAW to inhibit the growth of microorganisms in whiteleg shrimp and splendid squid demonstrated that the inactivation procedure involving soaking in PAW for 10 min resulted in a reduction in the number of total microorganisms to less than 6 log CFU/g. Additionally, an examination of the nutrition of aquaculture food revealed that PAW-immersed whiteleg shrimp and splendid squid showed different protein and lipid changes. The results suggested that PAW could be a viable option for decontaminating aquatic food products. However, it is important to consider that oxidation could pose a challenge in certain products. [ABSTRACT FROM AUTHOR]

Superheated steam (SS) is promising for the thermal shucking application of oysters due to its high energy. Tropical oysters Crassostrea iredalei was probed with K-type thermocouples connected to a datalogger to monitor and record process temperatures during superheated steam pretreatment at different temperatures (170, 210, and 250 °C) and holding time (4, 5, 6 min) followed by rapid ice immersion. The combination of heating and rapid chilling on the release of oyster meat during shucking was evaluated for muscle relaxation, muscle release, meat quality, texture profile analysis, and color and optimized for maximum muscle release and meat quality. The thermal profiles of SS revealed rapid temperature increment of both muscle and oyster shell compared to conventional steam, resulting in increased relaxation of adductor muscles and degree of meat release with an increase in temperature and time. Texture of the oyster meat retained the hardness, gumminess, and chewiness of the fresh oyster at low superheated steam temperature and short exposure time. Sufficient meat detachment of more than 85% was achieved at 170 °C and 5 min with minimum meat quality changes which were also lower in microbial load (4.1 × 103 CFU/g) and TVB-N (11.7 mg/100 g) with higher final pH (6.3) compared to untreated [microbial load (5.2 × 103 CFU/g), TVB-N (15.7 mg/100 g), final pH (5.9)] and microwave-treated [microbial load (4.3 × 103 CFU/g), TVB-N (21.0 mg/100 g), final pH (6.0)] samples. In sum, SS has the potential to minimize oyster shucking time and control microbial growth of shucked oysters without compromising meat quality. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop an innovative tomato cold soup fortified in bioactive compounds through the incorporation of UV-B–treated radish seeds. After a 20 kJ m−2 UV-B treatment, radish seeds increased their sulforaphene content by 30%. Different concentrations of UV-B–treated seeds (0, 0.5, 1.5, 3, and 5 g kg−1) were added to a chopped vegetables cold soup, mainly made of Kumato® cherry tomatoes as novelty, including pepper, cucumber, and garlic, which was stored for 8 days at 4 °C. Added seeds did not affect physicochemical quality attributes, microbial growth, nor sensory perception. Nevertheless, a dose-dependent behaviour was shown in glucoraphenin and sulforaphene content, according to concentrations of UV-B–treated seeds added. It was also appreciated after an in vitro digestion that the bioaccessible fraction of glucosinolates and isothiocyanates was kept constant throughout the refrigerated storage. The sulforaphene content of the soup increased by ~ 19% after 2 days at 4 °C, of which the 33% was bioaccessible (measured in vitro), and subsequently was degraded by ~ 20% after 8 days at 4 °C. [ABSTRACT FROM AUTHOR]

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Temperature control for fermentation is crucial as it directly affects microorganism growth, productivity, and metabolic activity. This work proposes a modified fractional order proportional‐integral‐derivative (FOPID‐DF) controller that incorporates the system model in the control loop configuration utilizing a differential filter for precise temperature control within a narrow operating range. PID, fractional order PID (FOPID), modified fractional order PID (MFOPID), and fractional order internal model control (IMC) controllers were also designed for comparative analysis. The simulation results demonstrated that the proposed FOPID‐DF controller outperforms the other designed controllers, shown by a 22.33% reduction in integral absolute error (IAE) and a 29.06% decrease in integral square error (ISE) compared to the FOPID controller and various other improved performance indicators. Parameter variation and noise analysis highlighted the ability of the controller to maintain stability and performance under changing conditions. The simulation outcomes suggested that the FOPID‐DF controller excels in temperature control, ensuring optimal microorganism growth and metabolic activity. [ABSTRACT FROM AUTHOR]

Plant extracts gained attention in the meat industry for their role in preventing microbial growth and oxidative deterioration. Antioxidant efficiency of various ratios (0.125, 0.25, 0.5, and 1%) of ethanolic or methanolic pomegranate peel (PP), beet leaf (BL), and broccoli flower (BF) extracts on cooked ground beef was investigated during refrigerated storage. Thiobarbituric acid reactive substances (TBARS), lipid hydroperoxide (LPO), p‐anisidine, cooking loss (CL), pH, and color analysis were performed. Results revealed that CL increased (p < .05) with 0.5 and 1% PE or 1% BF extracts, whereas no CL change was observed in other extract applications. Although using 0.5% and 1% of ethanolic or methanolic PP extracts caused lower pH than control (p < .05), no pH difference was found among other treatments. L* values were not affected by extract applications, whereas a* decreased and increased with PP and BL extract addition, respectively (p < .05). Meantime, a* values decreased and b* values increased by elevation in extract ratio (p < .05). In terms of solvent impact, methanolic PP and ethanolic BL extracts caused higher b* (p < .05), whereas no difference in b* was obtained between ethanolic or methanolic BL extracts. TBARS, LPO, and p‐anisidine analysis revealed that the highest lipid oxidation was obtained in control (p < .05). PP extract treatments exhibited the lowest lipid oxidation (p < .05). Lipid oxidation gradually increased in control and all extract‐incorporated samples during storage (p < .05). In extract‐incorporated samples, lipid oxidation decreased with increasing the extract ratio (p < .05). Lipid oxidation was inhibited more by all incorporation ratios for each tested extract compared to control (p < .05). Moreover, using 0.125% PP, 0.5% BL, or 1% BF extracts was more effective in lipid oxidation inhibition than BHT (p < .05). It may be concluded that PP, BL, and BF extracts may be utilized by the meat processors to achieve prolonged shelf life and improved quality features. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) is considered one of the most harmful bacteria to human health. Dentistry, like all healthcare disciplines, places great emphasis on preventing scenarios that may result in cross-infection. Although various tested and already used materials are suitable for filling the root canal system, Gutta-Percha (GP) remains the preferred and widely accepted gold standard. Objective: We performed an in vitro analysis of the contamination of GP points, regarding the strains of Methicillin-resistant (MRSA) and Methicillin-sensitive (MSSA) Staphylococcus aureus, using classical microbiology methods and molecular biology techniques. Methods: Gutta-Percha points of two different brands from opened packages (already in use for 1 month) were collected for analysis. The assessment involved incubating the GP points in Brain Heart Infusion (BHI) medium to detect microbial growth. Growing microorganisms were plated on a selective and differential chromogenic medium for MRSA/MSSA strains, and the identification of isolates was confirmed by Polymerase Chain Reaction (PCR). In the case of microbial growth, the GP point was submitted to a disinfection protocol. Results: From the 315 collected GP points, only 6 (1.9%) resulted in being positive for microbial growth. After confirmation by PCR, only one sample of the six GP points was contaminated by MRSA, and the remaining five were MSSA-contaminated. The disinfection protocol was effective in all contaminated GP points. Conclusions: The Gutta-Percha points from opened pre-sterilized packages showed a very low degree of contamination by MRSA/MSSA. However, the detection of MSSA and MRSA strains raises concerns about potential contamination in dental clinic environments, and this risk cannot be considered negligible. [ABSTRACT FROM AUTHOR]

Recently, products of plant origin have been utilized to extend the shelf life of meat products. This study examined the impact of hemp seed oil as a replacement for animal fat and sodium nitrite on the nutritional, physicochemical, technological, and sensory traits of fermented salamis. Five treatments were prepared: S0 (100 mg/kg NaNO2), S1 (2% hemp oil and 50 mg/kg NaNO2), S2 (4% hemp oil and 50 mg/kg NaNO2), S3 (2% hemp oil), and S4 (4% hemp oil). The addition of hemp seed oil did not affect proximate composition but improved fatty acid composition and lipid quality nutritional indices. Microbial growth was consistent across all treatments. Active acidity (pH) and water activity (aw) were influenced by hemp seed oil and/or sodium nitrite. Salamis containing only hemp seed oil exhibited lower redness and chroma values during storage. Hemp seed oil led to higher lipid peroxidation, mitigated by sodium nitrite. The addition of hemp seed oil and varying levels of sodium nitrite significantly impacted salami texture. Sensory evaluation showed consumer acceptance of hemp seed oil-enhanced salamis. In conclusion, hemp seed oil can be used as a functional ingredient to improve the nutritional value and healthiness of fermented meat products when combined with reduced sodium nitrite content. [ABSTRACT FROM AUTHOR]

Indigenous microbial enhanced oil recovery (IMEOR) is a promising alternative way to promote oil recovery. It activates oil recovery microorganisms in the reservoir by adding nutrients to the injected water, utilizing microbial growth and metabolism to enhance recovery. However, few studies have focused on the impact of injected nutrients on reservoir microbial community composition and potential functions. This limits the further strategic development of IMEOR. In this study, we investigated the effects of nutrition on the composition of the reservoir bacterial community and functions in the Qizhong block of Xinjiang Oilfield, China, by constructing a long core microbial flooding simulation device. The results showed that the microbial community structure of the reservoir changed from aerobic state to anaerobic state after nutrient injection. Reducing the nutrient concentration increased the diversity and network stability of the reservoir bacterial community. At the same time, the nitrogen metabolism function also showed the same change response. Overall, these results indicated that nutrition significantly affected the community structure and function of reservoir microorganisms. Injecting low concentrations of nutrients may be more beneficial to improve oil recovery. This study is of great significance for guiding IMEOR technology and saving costs at the field site. [ABSTRACT FROM AUTHOR]

Wound healing involves a carefully regulated sequence of events, encompassing pro-inflammatory and anti-inflammatory stages, tissue regeneration, and remodeling. However, in individuals with diabetes, this process gets disrupted due to dysregulation caused by elevated glucose levels and pro-inflammatory cytokines in the bloodstream. Consequently, the pro-inflammatory stage is prolonged, while the anti-inflammatory phase is delayed, leading to impaired tissue regeneration and remodeling with extended healing time. Furthermore, the increased glucose levels in open wounds create an environment conducive to microbial growth and tissue sepsis, which can escalate to the point of limb amputation. Managing diabetic wounds requires meticulous care and monitoring due to the lack of widely available preventative and therapeutic measures. Existing clinical interventions have limitations, such as slow recovery rates, high costs, and inefficient drug delivery methods. Therefore, exploring alternative avenues to develop effective wound-healing treatments is essential. Nature offers a vast array of resources in the form of secondary metabolites, notably polyphenols, known for their antimicrobial, anti-inflammatory, antioxidant, glucose-regulating, and cell growth-promoting properties. Additionally, nanoparticles synthesized through environmentally friendly methods hold promise for wound healing applications in diabetic and non-diabetic conditions. This review provides a comprehensive discussion and summary of the potential wound-healing abilities of specific natural polyphenols and their nanoparticles. It explores the mechanisms of action underlying their efficacy and presents effective formulations for promoting wound-healing activity. [ABSTRACT FROM AUTHOR]

Bread is one of the main foods which is consumed by people, especially in developing and underdeveloped countries. However, bread loses its freshness during a short storage period, and that is an important concern for bakery producers. The loss of bread freshness is mainly due to the staling and microbial contamination. Regarding the importance of bread in the diet of people all over the world, finding suitable solution to increase its shelf life is necessary. Generally, three aspects are needed to prolong the shelf life of bread and bakery products: i) preventing moisture migration from the product by using appropriate packaging; ii) controlling the formulation and process parameters to minimize the staling rate; and iii) controlling the conditions for minimal microbial growth. In this paper, some methods to increase the microbial shelf life of bread and bakery products are addressed. [ABSTRACT FROM AUTHOR]

Summary: A large fraction of plant litter comprises recalcitrant aromatic compounds (lignin and other phenolics). Quantifying the fate of aromatic compounds is difficult, because oxidative degradation of aromatic carbon (C) is a costly but necessary endeavor for microorganisms, and we do not know when gains from the decomposition of aromatic C outweigh energetic costs.To evaluate these tradeoffs, we developed a litter decomposition model in which the aromatic C decomposition rate is optimized dynamically to maximize microbial growth for the given costs of maintaining ligninolytic activity. We tested model performance against > 200 litter decomposition datasets collected from published literature and assessed the effects of climate and litter chemistry on litter decomposition.The model predicted a time‐varying ligninolytic oxidation rate, which was used to calculate the lag time before the decomposition of aromatic C is initiated. Warmer conditions increased decomposition rates, shortened the lag time of aromatic C oxidation, and improved microbial C‐use efficiency by decreasing the costs of oxidation. Moreover, a higher initial content of aromatic C promoted an earlier start of aromatic C decomposition under any climate.With this contribution, we highlight the application of eco‐evolutionary approaches based on optimized microbial life strategies as an alternative parametrization scheme for litter decomposition models. See also the Commentary on this article by Shao & Sulman, 243: 825–827. [ABSTRACT FROM AUTHOR]

In this study, four highly efficient protein-degrading bacteria (Siccibactercolletis, Bacillus thuringiensis, Bacillus cereus, and Bacillus sp. (in: Firmicutes)) were screened from soil and fermentation beds and prepared into a mixed microbial agent in a ratio of 1:1:1:1. The effects of inoculation with protein-degrading functional bacteria on nitrogen transformation rate, microbial community, and functional genes during chicken manure–rice husk composting were studied. With the addition of functional agents, the nitrogen loss in chicken manure composting was reduced to 17.05%, and ammonia emissions were also reduced. Firmicutes, Proteobacteria, Bacteroidetes, Cocci, and Actinobacteria became the dominant bacterial communities, accounting for 85.41%~98.52% of the overall bacterial community in the compost; it promoted the growth of microorganisms such as Pseudogracilibacillus and Lachnospiraceae in the compost. Metagenomic analysis revealed that the addition of functional bacterial agents enhanced the expression of nitrogen fixation genes (nifK, nifH, and glnA) during the high-temperature phase, increased the diversity of bacteria associated with the nitrogen cycle in the compost, and improved the absorption and fixation of nitrogen source elements by microorganisms. Additionally, it strengthened the correlation between microbial communities, the composting environment, and functional genes. This study provides a theoretical basis for the efficient application of microbial agents and the reduction of pollution in chicken manure hull composting. [ABSTRACT FROM AUTHOR]

Summary Experimental learning is indispensable for the understanding of (natural) scientific concepts. In order to counteract the didactic, methodological and structural challenges of experimentation in everyday school life, a concept for experiments from the "Experimentierkiste" is presented. Thematically, biotechnological approaches with relevance to everyday life are focused on for inquiry‐based STEM teaching. The growth and conditions of microorganisms are examined in detail and demonstrated in experiments with yeast and microalgae. The relevance of this topic is based on the socially relevant scientific significance of microbial processes, especially in the medical and biotechnological fields. The core concept of the experimental kit is an essential component for the implementation of such inquiry‐based topics with experiments in science lessons. On the topic of yeast, there is a free hands‐on experiment website www.kniffelix.de for individuals and school classes from 3rd–13th grade which enhances the learning experience. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine, at the phenotypic and molecular levels, resistance and virulence markers in Candida spp. isolated from community-acquired infections in Bucharest outpatients during 2021, and to demonstrate the efficiency of alternative solutions against them based on silver nanoparticles (AgNPs). Methods: A total of 62 Candida spp. strains were isolated from dermatomycoses and identified using chromogenic culture media and MALDI-TOF MS, and then investigated for their antimicrobial resistance and virulence markers (VMs), as well as for metabolic enzymes using enzymatic tests for the expression of soluble virulence factors, their biofilm formation and adherence capacity on HeLa cells, and PCR assays for the detection of virulence markers and the antimicrobial activity of alternative solutions based on AgNPs. Results: Of the total of 62 strains, 45.16% were Candida parapsilosis; 29.03% Candida albicans; 9.67% Candida guilliermondii; 3.22% Candida lusitaniae, Candia pararugosa, and Candida tropicalis; and 1.66% Candida kefyr, Candida famata, Candida haemulonii, and Candida metapsilosis. Aesculin hydrolysis, caseinase, and amylase production were detected in the analyzed strains. The strains exhibited different indices of adherence to HeLa cells and were positive in decreasing frequency order for the LIP1, HWP1, and ALS1,3 genes (C. tropicalis/C. albicans). An inhibitory effect on microbial growth, adherence capacity, and on the production of virulence factors was obtained using AgNPs. Conclusions: The obtained results in C. albicans and Candida non-albicans circulating in Bucharest outpatients were characterized by moderate-to-high potential to produce VMs, necessitating epidemiological surveillance measures to minimize the chances of severe invasive infections. [ABSTRACT FROM AUTHOR]

Despite the urgent need for new antibiotics, very few innovative antibiotics have recently entered clinics or clinical trials. To provide a constant supply of new drug candidates optimized in terms of their potential to select for resistance in natural settings, in vitro resistance-predicting studies need to be improved and scaled up. In this review, the following in vitro parameters are presented: frequency of spontaneous mutant selection (FSMS), mutant prevention concentration (MPC), dominant mutant prevention concentration (MPC-D), inferior-mutant prevention concentration (MPC-F), and minimal selective concentration (MSC). The utility of various adaptive laboratory evolution (ALE) approaches (serial transfer, continuous culture, and evolution in spatiotemporal microenvironments) for comparing hits in terms of the level and time required for multistep resistance to emerge is discussed. We also consider how the hit-to-lead stage can benefit from high-throughput ALE setups based on robotic workstations, do-it-yourself (DIY) continuous cultivation systems, microbial evolution and growth arena (MEGA) plates, soft agar gradient evolution (SAGE) plates, microfluidic chips, or microdroplet technology. Finally, approaches for evaluating the fitness of in vitro-generated resistant mutants are presented. This review aims to draw attention to newly emerged ideas on how to improve the in vitro forecasting of the potential of compounds to select for resistance in natural settings. [ABSTRACT FROM AUTHOR]

Most of the artworks stored in museums are often kept in inappropriate climatic and environmental conditions that facilitate the formation and growth of microorganisms, such as fungi, which are responsible for many types of biodegradation phenomena. To mitigate and prevent these deteriorative processes, functionalized packaging materials can be used for the storage and handling of artworks. The aim of this study was to develop a potential anti-biodeterioration coating suitable for packaging purposes. TiO2 and ZnO doped with different amounts of Ag (0.5 wt%, 1 wt%, and 3 wt%) were synthesized and dispersed in polyvinyl alcohol (PVA) and acrylic resin (Paraloid B72), then applied on different types of packaging materials (cellulose and the high-density spunbound polyethylene fiber Tyvek®, materials that are frequently used as packaging in museums). Analytical investigations (SEM/EDS, Raman, FTIR, and XRD) were employed to assess dispersion on the packaging material. Furthermore, resistance against biodeteriogens was assessed using Cladosporium sp., a bioluminometer, to define the biocidal efficacy. [ABSTRACT FROM AUTHOR]

The freshwater snails and mussels are recognized as ecosystem engineers owing to their ability to influence the ecological processes. We investigated the effect of the snail Filopaludina bengalensis and the mussel Lamellidens marginalis alone and in interaction with the macrophyte Lemna minor on the ecological processes (nutrient dynamics, microbial account, sediment properties and periphytic algal growth) of the freshwater ecosystem through a mesocosm experiment. Both the snail and mussel promoted the growth rate of L. minor; however, the presence of snail negatively influenced the growth of periphyton. The biogeochemical process was affected by the presence of snails and mussels. Macrophyte association further influenced this biogeochemical process. Snail and mussel enhance the growth of heterotrophic bacteria and phosphate solubilising bacteria in the sediment. Likewise, the presence of macrophyte also positively influences the microbial growth. The activities of the benthic fauna like the mussels and the snails can be considered a useful process for the sustenance of the microbes and the macrophytes representing a pattern of bottom-up regulation. [ABSTRACT FROM AUTHOR]

Objective: In this work, in order to optimize the structure of histidine-containing antifungal peptides with a "linear" type of amphipathicity (LTA), we carried out the synthesis and comparative screening of the antifungal activity of a series of histidine-containing SAMPs (F2H7, F2H10, F2H13, F2H16, H10, H10F2) with a "linear" type of amphipathicity that we constructed de novo. We also aimed to study their hemolytic properties, to assess their therapeutic index, and to compare the obtained results with similar data for the antifungal histidine-rich 12-mer peptide P113 (AKRHHGYKRKFH), a drug candidate known as PAC-113, one of the shortest and most active analogues of the natural antifungal histidine-rich peptide Hst 5. Methods: Peptides were synthesized by a solid phase method using a Fmoc-based strategy. To determine the antifungal activity of the peptides, we used the opportunistic fungus strain Candida albicans EMTK 34. The number of microorganisms (titer) in the suspension was determined by optical density at a wavelength of 595 nm. To determine the antifungal activity of the peptides, cell cultures were co-incubated with the studied peptides in 96-well plates. The cells were incubated with the drug for 24 h at 37°C. To assess the antifungal activity of the studied peptides, their minimum inhibitory concentrations (MIC50) were determined, i.e. such peptide concentration at which the growth of microorganisms was suppressed by 50%. To assess the toxicity of the peptides, their hemolytic activity was determined, which was tested against fresh human erythrocytes using a photometric method. To assess the selectivity of the action of peptides, the values of the minimum hemolytic concentration (MHC) of the peptides were determined and the values of their therapeutic index (TI) were calculated as the ratio of the minimum hemolytic concentration (MHC) to the MIC50 value. Results and Discussion: It was shown that the antifungal activity of the studied SAMPLTA increases with an increase in the number of histidine residues in their composition, reaching the maximum value for the histidine-containing peptide F2H16 (MIC50 = 1.0 µM). It has been shown that as the chain length of peptides increases, their hemolytic toxicity also increases. The TI values for these peptides were 233, 247, 79, and 60, respectively. It has been shown that, against C. albicans, histidine-containing SAMP-LTA derivatives with phenylalanine residues at the N-terminus of the peptide (F2H10) are less effective compared to similar peptides (H10F2) containing phenylalanine residues at the C-terminus. Among the studied peptides, the most active was the H10 peptide (MIC50 = 0.7 µM), which does not contain phenylalanine residues, which in its antifungal activity is not only more effective than all other histidine-containing peptides, including the F2H16 peptide with 16 histidine residues, but also 4– 5 times more effective than the antifungal peptide P113 (MIC50 = 3.4 µM), a short active fragment of natural Hst 5, well known from the literature. Among all the studied peptides, H10 and P113 have minimal (almost zero) values of hemolytic activity. However, due to its higher antifungal activity, the selectivity of the H10 peptide (TI > 1400) exceeds the selectivity of the P113 peptide (TI > 340) by more than 4 times. Conclusions: Thus, peptide H10, due to its high antifungal activity, low hemolytic toxicity and, accordingly, high therapeutic significance, can be used as a promising antifungal peptide drug. [ABSTRACT FROM AUTHOR]

The rapid growth of organic solid waste has recently exacerbated environmental pollution problems, and its improper treatment has led to the loss of a large number of biomass resources. Here, we expound the advantages of microbial agents composting compared with conventional organic solid waste treatment technology, and review the important role of microbial agents composting in organic solid waste composting from the aspects of screening and identification, optimization of conditions, mechanism of action, combination with other technologies and ultra‐high‐temperature and ultra‐low‐temperature microbial composting. We discuss the value of microorganisms with different growth conditions in organic solid waste composting, and put forward a seasonal multi‐temperature composite microbial composting technology. Provide new ideas for the all‐round treatment of microbial agents in organic solid waste in the future. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Exopolysaccharides (EPSs) are carbohydrate polymers that are synthesized and secreted into the extracellular during the growth of microorganisms. Bacillus thuringiensis (Bt) is a type of entomopathogenic bacterium, that produces various insecticidal proteins and EPSs. In our previous study, the EPSs produced by Bt strains were first found to enhance the toxicity of insecticidal crystal proteins against Plutella xylostella. However, the response of the intestinal bacterial communities of P. xylostella under the action of EPSs is still unelucidated. In this study, 16S rRNA amplicon sequencing was used to characterize the intestinal bacterial communities in P. xylostella treated with EPSs alone, Cry1Ac protoxin alone, and both the Cry1Ac protoxin and EPSs. Compared with the control group, alpha diversity indices, the Chao1 and ACE indices were significantly altered after treatment with EPSs alone, and no significant difference was observed between the groups treated with Cry1Ac protoxin alone and Cry1Ac protoxin + EPSs. However, compared with the gut bacterial community feeding on Cry1Ac protoxin alone, the relative abundance of 31 genera was significantly changed in the group treated with Cry1Ac protoxin and EPSs. The intestinal bacteria, through the oral of Cry1Ac protoxin and EPSs, significantly enhanced the toxicity of the Cry1Ac protoxin towards the axenic P. xylostella. In addition, the relative abundance of the 16S rRNA gene in the chloroplasts of Brassica campestris decreased after adding EPSs. Taken together, these results show the vital contribution of the gut microbiota to the Bt strain-killing activity, providing new insights into the mechanism of the synergistic insecticidal activity of Bt proteins and EPSs. [ABSTRACT FROM AUTHOR]

AbstractGlobal energy demand is experiencing a notable surge due to growing energy security. Renewable energy sources, like ethanol, are becoming more viable. In the present study, the application of a PSO-PID (Particle Swarm Optimization – Proportional Integral Derivative) controller with a split-range control strategy was suggested for the regulation of temperature within the fermentation system. To optimize performance, a POS-PID controller with a split-range arrangement utilizing two control valves for hot and cold utilities was constructed. The study began by examining the open-loop dynamic response of the system to inlet temperature and concentration disturbances during ethanol production fermentation. Subsequently, a transfer function model was developed through linearization at the steady-state operating point. The split-range controller structure, implemented by optimizing the PSO-PID controller parameters using PSO, effectively demonstrated temperature control in simulations of a nonlinear model. In this investigation, the ethanol fermentation system was modeled as a CSTR using a modified Monod equation for microbial growth kinetics. Various dynamic behavioral disturbances were explored and verified in the model with plant data in this study. The simulation model results were validated through plant data. The proposed method showed superior closed-loop performance with respect to errors, with the actuators proving to be effective than other reported methods for temperature control. [ABSTRACT FROM AUTHOR]

Background Results Conclusion Practical applications The use of natural antioxidants and antimicrobials in dairy production can increase the variety of dairy‐based products. In this study, the antioxidant and antimicrobial changes in lactic butter samples made from heat‐treated creams and enriched with M. communis essential oils (EOs) were investigated.The best lactic butter properties were achieved by optimizing the process at 70 and 80 °C. M. communis EOs decreased lipid oxidation and spoilage microorganism growth in lactic butter during cold storage. M. communis EOs have antioxidant and antimicrobial activity in lactic butter equal to that of ascorbyl palmitate. α‐Pinene, p‐cymene, limonene, 3‐carene, 1,8‐cineol, β‐linalool, α‐terpineol and myretenol are the major contributors to the antioxidant and antimicrobial activities of M. communis EOs. They exhibit antioxidant activity by neutralizing free radicals by donating hydrogen or acting as termination enhancers, and antimicrobial activity by disruption of cell membranes, which may result in the leakage of macromolecules or the loss of essential metabolites, ultimately leading to cell death during the storage of lactic butter samples.The addition of M. communis EOs improves lactic butter stability equal to that of ascorbyl palmitate, and may be applied as a natural and effective preservative to maintain butter from lipid oxidation and microbial spoilage and enhance its safety.The growing recognition of the health benefits of natural antioxidants, as opposed to synthetic ones, has led to the development of new applications for natural antioxidants. In this regard, M. communis L. EOs can be used to enhance the shelf stability of cold‐stored lactic butter. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, three different groups of sausages were produced from thornback ray (Raja clavata) without additives (control group), waste pomegranate peel extract (natural group), and ascorbic acid (synthetic group). Biochemical, physicochemical, and microbiological changes of sausages were examined under refrigerator conditions (+4°C), and the shelf life was determined. The best results in terms of nutritional and physicochemical values were obtained in sausages treated with pomegranate peel extract. All sausage groups were spoiled on the 15th day in terms of the total volatile basic nitrogen (TVB‐N); however, the pomegranate peel extract group showed a more positive effect compared to the other sausage groups. However, this value was not considered because cartilaginous fish such as stingrays contain higher levels of nonprotein nitrogenous compounds. It was observed that microbial growth was less in the natural group and the antimicrobial effect of pomegranate peel extract was higher than that of ascorbic acid. In addition, it was determined that the pomegranate peel extract group extended the shelf life up to 6 days in terms of total viable count (TVC) and yeast/mold compared to the control and synthetic groups, respectively. This study showed that pomegranate peel extract has a better protective effect than ascorbic acid and it can be used as a natural additive in preserving the quality of seafood products. [ABSTRACT FROM AUTHOR]

This research was undertaken to assess the effect of tragacanth gum–chitin nanofiber (TG–CNF) film containing free (CEO) or encapsulated cumin essential oil (CNE) combined with oxygen absorber (OA) packaging on the shelf‐life of ready‐to‐cook (RTC) turkey breast burgers during chilled storage. The experimental groups were OA and TG–CNF as single treatments, TG–CNF + CEO, TG–CNF + CNE, and TG–CNF + OA as binary treatments, TG–CNF + CEO + OA and TG–CNF + CNE + OA as ternary treatments, and control. The samples were stored at 3°C for 20 days and analyzed for microbial, physicochemical, and sensory attributes. Binary treatments, when compared to single treatments, and ternary treatments, when compared to binary treatments, exhibited enhanced effectiveness in managing microbial growth, hindering physicochemical alterations, and decelerating sensory alterations. At day 20, TG–CNF + CNE + OA group was identified as the most effective group in inhibiting the growth of total mesophilic bacteria (TMB), total psychrophilic bacteria (TSB), and coliforms (final counts were 4.8, 4.16, and ≤1 log CFU/g, respectively), and TG–CNF + CNE + OA and TG–CNF + CEO + OA groups were known as the most effective groups in inhibiting lactic acid bacteria (LAB) (final counts were 4.71 and 5.15 log CFU/g, respectively). Furthermore, the TG–CNF + CNE + OA treatment proved to be the most effective group in reducing the total volatile nitrogen (TVN) (final level was 19.2 mg N/100 g) and thiobarbituric acid reactive substances (TBARS) (final level was 0.119 mg malondialdehyde (MDA)/kg). TG–CNF + CNE + OA and TG–CNF + CEO + OA were the most efficient groups to delay the increasing rate of cooking loss (final values were 23.3% and 24.6%) and pH (final values were 7.01 and 6.99). The sample's shelf‐life was 4 days in control and TG–CNF, 8 days in OA and TG–CNF + OA, 12 days in TG–CNF + CEO, 16 days in TG‐CNF + CNE and TG–CNF + CEO + OA, and at least 20 days in TG–CNF + CNE + OA. As a result, the incorporation of TG–CNF + CNE alongside OA packaging emerges as a highly effective active packaging method for preserving RTC turkey breast burgers during chilled storage. [ABSTRACT FROM AUTHOR]

Soil microbial traits and functions play a central role in soil organic carbon (SOC) dynamics. However, at the macroscale (regional to global) it is still unresolved whether (i) specific environmental attributes (e.g., climate, geology, soil types) or (ii) microbial community composition drive key microbial traits and functions directly. To address this knowledge gap, we used 33 grassland topsoils (0–10 cm) from a geoclimatic gradient in Chile. First, we incubated the soils for 1 week in favorable standardized conditions and quantified a wide range of soil microbial traits and functions such as microbial biomass carbon (MBC), enzyme kinetics, microbial respiration, growth rates as well as carbon use efficiency (CUE). Second, we characterized climatic and physicochemical properties as well as bacterial and fungal community composition of the soils. We then applied regression analysis to investigate how strongly the measured microbial traits and functions were linked with the environmental setting versus microbial community composition. We show that environmental attributes (predominantly the amount of soil organic matter) determined patterns of MBC along the gradient, which in turn explained microbial respiration and growth rates. However, respiration and growth normalized for MBC (i.e., specific respiration and growth) were more linked to microbial community composition than environmental attributes. Notably, both specific respiration and growth followed distinct trends and were related to different parts of the microbial community, which in turn resulted in strong effects on microbial CUE. We conclude that even at the macroscale, CUE is the result of physiologically decoupled aspects of microbial metabolism, which in turn is partially determined by microbial community composition. The environmental setting and microbial community composition affect different microbial traits and functions, and therefore both factors need to be considered in the context of macroscale SOC dynamics. [ABSTRACT FROM AUTHOR]

Solid-state fermentation (SSF) is the bioprocess where microorganisms are cultivated in the absence of free water under controlled conditions. Lactic acid can be produced by Rhizopus oryzae SSF of grape stalks. During the microorganism's growth, the temperature and water content of the solid bed fluctuate, leading to areas of either dry or excessive moisture in the solid substrate. Therefore, it is crucial to control the water supply to the matrix. In this work, we obtain lactic acid through SSF of grape stalks using Rhizopus oryzae NCIM 1299. The SSF was conducted at a fixed temperature of 35 °C, with five constant relative humidity (RH) levels: 50, 57, 65, 72, and 80%RH. Mathematical models, including the Logistic and First-Order Plus Dead-Time models for fungal biomass growth and the Luedeking and Piret with Delay Time model for lactic acid production, were adjusted to kinetic curves. Growth kinetic parameters (Xmax, μmax, Tp, T0, Yp/x, and td) were determined for all conditions. These kinetic parameters were then correlated with relative humidity using a second-degree polynomial relationship. We observed a decrease in Xmax with an increasing %RH, while the value of Yp/x increased at a higher %RH. Finally, the optimal variable relative humidity profile was obtained by applying the dynamic optimization technique, resulting in a 16.63% increase in lactic acid production. [ABSTRACT FROM AUTHOR]

Fresh-cut radishes are susceptible to quality loss and microbial contamination during storage, resulting in a short shelf life. This study investigated the effects of photodynamic technology (PDT) on fresh-cut radishes stored at 4 °C for 10 d and developed appropriate models to predict the shelf life. Results showed that curcumin-mediated PDT maintained sensory acceptability, color, and firmness, decreased weight loss, and increased ascorbic acid and total phenolics of samples by inactivating polyphenol oxidase and peroxidase, resulting in improved antioxidant capacity and quality. The total bacteria count in samples was significantly (p < 0.05) reduced by 2.01 log CFU g−1 after PDT and their shelf life was extended by 6 d compared to the control. To accurately predict the shelf life, the kinetic models based on microbial growth were established, while weight loss, b* value, firmness, and ascorbic acid were selected as representative attributes for developing quality-based prediction models through correlation analysis. Modeling results showed prediction models based on ascorbic acid best fitted PDT-treated samples, while the modified Gompertz model based on bacteria growth was the best for control and samples treated by sodium hypochlorite. This study suggests that PDT is promising in extending the shelf life of fresh-cut radishes, and using critical indexes to establish the prediction model can provide a more reliable shelf-life estimation. [ABSTRACT FROM AUTHOR]

Ceramic materials have a very long tradition of use in construction. Their durability is related to the surface of the material and the action of the corrosive environment. One of the corrosive factors acting on ceramic materials is microorganisms. They can contribute to the deterioration of the technical and performance properties of building materials. Aesthetic, physical, and chemical deterioration are considered to be the main destructive processes in ceramic materials. This work shows how the different types of the most commonly used ceramic materials, i.e., brick and tiles, are damaged. Each of these types is susceptible to microbial growth. Most microorganisms that occur on ceramic materials produce staining substances and thus form coloured biofilms. The direct action of metabolic products secreted by organisms on inorganic substrates is the main cause of chemical biodeterioration. Therefore, this work presents the impact of microorganisms on ceramic building materials. [ABSTRACT FROM AUTHOR]

Pollutant degradation and heavy-metal resistance may be important features of the rhizobia, making them promising agents for environment cleanup biotechnology. The degradation of phenanthrene, a three-ring polycyclic aromatic hydrocarbon (PAH), by the rhizobial strain Rsf11 isolated from the oil-polluted rhizosphere of alfalfa and the influence of nickel ions on this process were studied. On the basis of whole-genome and polyphasic taxonomy, the bacterium Rsf11 represent a novel species of the genus Neorhizobium, so the name Neorhizobium phenanthreniclasticum sp. nov. was proposed. Analysis of phenanthrene degradation by the Rsf1 strain revealed 1-hydroxy-2-naphthoic acid as the key intermediate and the activity of two enzymes apparently involved in PAH degradation. It was also shown that the nickel resistance of Rsf11 was connected with the extracellular adsorption of metal by EPS. The joint presence of phenanthrene and nickel in the medium reduced the degradation of PAH by the microorganism, apparently due to the inhibition of microbial growth but not due to the inhibition of the activity of the PAH degradation enzymes. Genes potentially involved in PAH catabolism and nickel resistance were discovered in the microorganism studied. N. phenanthreniclasticum strain Rsf11 can be considered as a promising candidate for use in the bioremediation of mixed PAH–heavy-metal contamination. [ABSTRACT FROM AUTHOR]

Quantitative understanding of microbial growth is an essential prerequisite for successful control of pathogens as well as various biotechnology applications. Even though the growth of cell populations has been extensively studied, microbial growth remains poorly characterised at the spatial level. Indeed, even isogenic populations growing at different locations on solid growth medium typically show significant location-dependent variability in growth. Here we show that this variability can be attributed to the initial physiological states of the populations, the interplay between populations interacting with their local environment and the diffusion of nutrients and energy sources coupling the environments. We further show how the causes of this variability change throughout the growth of a population. We use a dual approach, first applying machine learning regression models to discover that location dominates growth variability at specific times, and, in parallel, developing explicit population growth models to describe this spatial effect. In particular, treating nutrient and energy source concentration as a latent variable allows us to develop a mechanistic resource consumer model that captures growth variability across the shared environment. As a consequence, we are able to determine intrinsic growth parameters for each local population, removing confounders common to location-dependent variability in growth. Importantly, our explicit low-parametric model for the environment paves the way for massively parallel experimentation with configurable spatial niches for testing specific eco-evolutionary hypotheses. Author summary: Image-based platforms allow obtaining population size estimates for massively parallel growth experiments on substrate plates at a relatively low cost. However, such population size data has been shown to display a high degree of spatial variability, which occurs even with isogenic populations. Here we first quantified the importance of spatial location on growth variation using a machine learning approach, and then developed spatially aware population growth models to explain the spatial structure of the growth data. Ultimately, we show that a spatial resource consumer model with local microhabitats connected via diffusion, and a parameter capturing the initial physiological state of a population, can fully explain the observed spatial variation in growth while allowing the inference of intrinsic growth parameters of specific populations. This result provides a method for systematic extraction of spatial growth models and paves the way for massively parallel eco-evolutionary experimentation. [ABSTRACT FROM AUTHOR]

Identifying the nutritional requirements and growth conditions of microorganisms is crucial for determining their applicability in industry and understanding their role in clinical ecology. Predatory bacteria such as Bdellovibrio bacteriovorus have emerged as promising tools for combating infections by human bacterial pathogens due to their natural killing features. Bdellovibrio's lifecycle occurs inside prey cells, using the cytoplasm as a source of nutrients and energy. However, this lifecycle supposes a challenge when determining the specific uptake of metabolites from the prey to complete the growth inside cells, a process that has not been completely elucidated. Here, following a model-based approach, we illuminate the ability of B. bacteriovorus to replicate DNA, increase biomass, and generate adenosine triphosphate (ATP) in an amino acid-based rich media in the absence of prey, keeping intact its predatory capacity. In this culture, we determined the main carbon sources used and their preference, being glutamate, serine, aspartate, isoleucine, and threonine. This study offers new insights into the role of predatory bacteria in natural environments and establishes the basis for developing new Bdellovibrio applications using appropriate metabolic and physiological methodologies. Key points: • Amino acids support axenic lifestyle of Bdellovibrio bacteriovorus. • B. bacteriovorus preserves its predatory ability when growing in the absence of prey. [ABSTRACT FROM AUTHOR]

Capsules have been investigated as a popular oral dosage form among communities due to their simplicity and ease of production. Capsules that are considered in the gastro-resistance category can be very beneficial due to enhanced drug absorption, improved stability, targeted release, etc. This study investigated the effect of enteric polymers on uncoated hard capsule fabrication and dissolution properties. The polymers used in this study included HPMCPh and Eudragit L100-55. Eight different formulations based on HPMCPh, Eudragit, and gelatin were examined to identify the ideal formulation for the product of uncoated enteric hard capsules with preferred physicochemical and gastro-resistance properties. The results reveal that the capsules containing Eudragit (F1), HPMCPh (F2), Eudragit/HPMCPh/gelatin (F3), and Eudragit/gelatin (F4) are steady within the simulated stomach environment, and drug release does not occur for 120 min. The outcomes demonstrate that, among the proposed formulas, the F4 formula is suitable both in terms of capsulation form and delayed-release properties and shows no microbial growth. The properties of the optimized sample were studied by FTIR, FESEM, tensile strength, humidity, and rheology. The results illustrated that gelatin-based hydrogels with Eudragit (F4) are potential candidates for manufacturing uncoated enteric hard capsules that inhibit drug release in a gastric pH medium and act as a pH-sensitive drug-release system. [ABSTRACT FROM AUTHOR]

Background: Characterization of microbial growth is of both fundamental and applied interest. Modern platforms can automate collection of high-throughput microbial growth curves, necessitating the development of computational tools to handle and analyze these data to produce insights. Results: To address this need, here I present a newly-developed R package: gcplyr. gcplyr can flexibly import growth curve data in common tabular formats, and reshapes it under a tidy framework that is flexible and extendable, enabling users to design custom analyses or plot data with popular visualization packages. gcplyr can also incorporate metadata and generate or import experimental designs to merge with data. Finally, gcplyr carries out model-free (non-parametric) analyses. These analyses do not require mathematical assumptions about microbial growth dynamics, and gcplyr is able to extract a broad range of important traits, including growth rate, doubling time, lag time, maximum density and carrying capacity, diauxie, area under the curve, extinction time, and more. Conclusions: gcplyr makes scripted analyses of growth curve data in R straightforward, streamlines common data wrangling and analysis steps, and easily integrates with common visualization and statistical analyses. [ABSTRACT FROM AUTHOR]

Rhizodeposition fuels carbon (C) and nutrient cycling in soil. However, changes in the dynamics of microbial growth on rhizodeposits with increasing distance from the root is not well studied. This study investigates microbial growth on individual organic components of rhizodeposits and maize root‐derived exudates and mucilage from agricultural soil. By creating a gradient of substrate concentrations, we simulated reduced microbial access to rhizosphere C with increasing distance to the root surface. We identified distinct C‐thresholds for the activation of microbial growth, and these were significantly higher for rhizodeposits than singular, simple sugars. In addition, testing for stoichiometric constraints of microbial growth by supplementing nitrogen (N) and phosphorus (P) showed accelerated and increased microbial growth by activating a larger proportion of the microbial biomass. Early and late season exudates triggered significantly different microbial growth responses. The mineralization of early‐season exudates was induced at a high C‐threshold. In contrast, the mineralization of late‐season exudates showed 'sugar‐like' properties, with a low C‐threshold, high substrate affinity, and a reduced maximum respiration rate of microorganisms growing on the added substrate. Mucilage exhibited the highest C‐threshold for the activation of microbial growth, although with a short lag‐period and with an efficient mucilage degradation comparable to that of sugars. By determining kinetic parameters and turnover times for different root‐derived substrates, our data enable the upscaling of micro‐scale processes to the whole root system, allowing more accurate predictions of how rhizodeposition drives microbial C and nutrient dynamics in the soil. [ABSTRACT FROM AUTHOR]

Summary: Shrimp undergo rapid deterioration after death, primarily due to enzyme activity and microbial growth, with freezing serving as its primary preservation method. In this study, shrimp underwent both conventional freezing (CF) and magnetic field‐assisted freezing (MF), and the shrimp meat's metabolites were scrutinised via metabonomic analysis techniques. The results demonstrate that MF treatment effectively preserved umami components like glutamic acid (log2(FC) = 0.37) and inosinic acid (1.02) while inhibiting the accumulation of spoilage‐related metabolites such as inosine (HxR) (−2.51), hypoxanthine (Hx) (−1.43) and uric acid (UA) (−1.24). Moreover, specific compounds, including 3‐methylhistidine, 1,6‐bisphosphate, phosphatidylcholine (PC), phosphatidylethanolamine (PE), HxR, Hx and UA were recognised as potential biomarkers throughout the freezing process. This research offers crucial insights into the intricate molecular mechanisms behind magnetic field‐assisted freezing. [ABSTRACT FROM AUTHOR]

The colonisation of building materials by microorganisms is the first step in terms of a subsequent biodeterioration and an occurrence of potential building-associated health hazards. Contrary to many studies to date, focusing mainly on old buildings with symptoms of biocorrosion, this research focuses on the bioreceptivity of selected unused building materials and the factors determining the intensity of their colonisation. The experiments were carried out in parallel in India and Poland, with the use of indigenous microflora from a given region. They revealed the similar dynamics of the microbial multiplication in concrete and plasterboard and the extreme intensity of the process: after only 10 weeks under favorable conditions, the number of bacteria and fungi reached 107 CFU/g of dry weight of the material. The stimulation of microbial growth by individual environmental factors was slightly different in Indian and Polish studies: in India, the strongest stimulating factor was the periodic increase in humidity, while in Poland, the highest intensification of growth was observed in samples enriched with organic matter. Mould biodiversity turned out to be higher in India, although some types of fungi common to both regions were isolated. [ABSTRACT FROM AUTHOR]

BACKGROUND: Vacuum packaging has the ability to reduce oxidative deterioration and microbial‐induced spoilage of meat. However, in an oxygen‐free environment, it can lead to the development of an unappealing purplish‐red color and a decrease in the water‐holding capacity of meat, thereby impacting the overall meat quality. Portulaca oleracea L. (POL) is a homology of medicine and food known for its exceptional antioxidant and antimicrobial properties. RESULTS: The aim of our present study was to investigate the antioxidant and antimicrobial ability of n‐butanol phase extract of POL and the effect of POL extract incorporation on the quality (water‐holding capacity, shear force, color, and texture) and physicochemical (pH, total volatile base nitrogen, and total viable counts) attributes of vacuum‐packed seasoned steaks at 4 °C over a 15‐day period. Results showed that the POL extract had excellent antioxidant and antimicrobial capacity. Furthermore, the addition of POL extract significantly inhibited protein oxidation and microbial growth of steaks (P < 0.05), and improved the water‐holding capacity, color properties, and tenderness (P < 0.05). Moreover, there were no significant differences (P > 0.05) in the color, water‐holding capacity, or tenderness between the 0.5 and 1 g kg−1 POL extract treatment groups compared to the sodium nitrite control group. CONCLUSION: These results indicate that POL extract had the potential to replace sodium nitrite due to its ability to hinder protein oxidation and microbial growth of vacuum‐packed seasoned steaks, while enhancing the color, water‐holding capacity, and tenderness of seasoned steaks. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Fresh insects in the form of paste can be conveniently utilised for further food preparations and processing at both household and industrial levels. However, due to the high moisture content and particular physiochemical properties, insect paste is highly unstable and susceptible to significant quality changes during storage. The aim of this study was to evaluate the microbiological and physicochemical stability of high hydrostatic pressure (HHP) treated Tenebrio molitor paste stored at different modified atmosphere packaging (MAP) conditions. Three different MAP compositions and normal air were applied. pH, colour, lipid oxidation, fluorescence spectra and microbiological parameters were evaluated along 28 days of refrigerated storage (4 °C). HHP treatment (600 MPa, 5 min) resulted in a significant reduction in mesophilic aerobic bacteria, anaerobic bacteria and yeast and mould counts. Growth of mesophilic aerobic and anaerobic bacteria remained low for 7 days at 4 °C, regardless of the applied atmospheric conditions, while high microbial growth was observed after 14 days without any significant differences among the treatments. The number of mesophilic spores remained low throughout the entire storage period when MAP was applied, whereas high values were observed after 28 days in the samples stored in normal air. Listeria monocytogenes, Salmonella spp. and Escherichia coli were not detected in any of the samples, nor in the raw paste. Lipid oxidation was initiated by the HHP treatment and displayed an increasing trend during the storage period, although the oxidation levels were lower in the MAP without oxygen compared to the normal air packaging and in MAPs with high O2 or CO2 levels. Fluorescence spectroscopy showed high potential for rapid detection of chemical changes in insect products during processing and storage. Overall, this study showed that MAP can effectively be applied on HHP-treated insect paste to extend its storage period. Absence of oxygen has been identified as a crucial factor in achieving reduced microbial growth and ensuring high physiochemical quality of the final product. Therefore, the present research offers a valuable insight for creating new edible insect-based products within the food industry. [ABSTRACT FROM AUTHOR]

Raising fish in ponds for an extended period can have an impact on the accumulation of bacteria that can affect the health of the fish. Using plant extracts is an interesting option to consider for reducing bacterial contamination in ponds. This study investigated the effectiveness of cinnamon extract in reducing bacterial contamination in the water used for raising Siamese fighting fish (Betta splendens). Optimal concentrations of cinnamon extract were determined for microbial reduction in the water used for the cultivation of these fish. Test the ability to resist infection at the concentrations of cinnamon extract 1:1, 1:2, 1:4, 1:8, 1:16, and 1:64, against 3 bacterial species (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa). The concentrations of cinnamon extract at 1:1 and 1:2 inhibited all three tested pathogens, while up to 1:4 inhibited S. aureus. Water samples taken from the ponds for testing were studied at 4 cinnamon extract concentrations: 0, 1, 2, and 3 gL-1. The treated water samples were collected at 0, 24, and 48 hours to quantify microbial activity. There were significant (p<0.05) differences among the concentrations, with the numbers of microorganisms in the treated water at 48 hours being 3.84x105, 2.92x104, 2.69x10³, and 2.89x10³ CFU mL-1, respectively. The experimental groups with concentrations of 2 and 3 gL-1 were the most effective in reducing bacteria in the fishpond after 24 h. Our study demonstrated that cinnamon extract could reduce microbial growth in water used to raise Siamese fighting fish. [ABSTRACT FROM AUTHOR]

The cheese ripening period, in which biochemical changes occur under specific temperature and humidity conditions, is crucial for making the finished product marketable. However, the food matrix can become a growth medium for developing spoilage microorganisms and fungi. In dairy factory, contamination of the crust area can be monitored with several wasteful and time-expensive methods, i.e., the use of saline solutions and/or the brushing of cheese wheels. This study investigates the effectiveness of different ozone treatments, 400 ppb, 8 hours (overnight) every other day until the end of ripening, and 300 ppb, 8 hours per day (overnight) for the entire ripening duration compared to control sample in normal atmosphere, in controlling microbial and fungal growth during the ripening of Toma Piemontese PDO cheese. Results showed that ozone treatments significantly affect spoilage microflora, preserving the overall quality parameters (i.e., weight loss, customer value, and greater sensory nuances). [ABSTRACT FROM AUTHOR]

This work presents a low-cost, open-source turbidimeter, the 'Erlenmeter', designed to monitor the growth of microorganisms in batch cultures. It is easy to build, based exclusively on inexpensive off-the-shelf electronic components and 3D-printed parts. The Erlenmeter allows measuring the optical density of cultures on standard Erlenmeyer flasks without the need to open the flasks to collect aliquots, ensuring speed, minimal use of consumables, and elimination of the risk of contamination. These features make it particularly well-suited not just for routine research assays but also for experimental teaching. Here we illustrate the use of the Erlenmeter turbidimeter to record the growth of the microalga Phaeodactylum tricornutum, of the bacterium Escherichia coli, and of the yeast Saccharomyces cerevisiae, model organisms that are widely used in research and teaching. The Erlenmeter allows a detailed characterization of the growth curves of all organisms, confirming its usefulness for studying microbial populations dynamics both for research purposes and in classroom settings. [ABSTRACT FROM AUTHOR]

In this study, we monitored the fermentative process of Vitis vinifera L. leaves (grapevine), spontaneously or promoted by Saccharomyces cerevisiae, in both solid and liquid media. We also aimed to evaluate the effect on the bioactivity and shelf life of yogurt incorporating fermented and non-fermented grapevine leaves compared to yogurt produced with the preservative potassium sorbate. The results revealed that fermented grapevine leaf extracts increased their bioactive compounds and antioxidant activity, particularly in fermentations in a solid medium. In yogurt samples with incorporation extract from solid spontaneous fermentation and extract from solid yeast fermentation, even in small quantities, they exhibited higher levels of total phenols (1.94 and 2.16 mg GAE/g of yogurt, respectively) and antioxidant activity (5.30 and 5.77 mg TroloxE/g of yogurt; and 1.33 and 1.34 mg Fe(II)E/g of yogurt, respectively) compared to control yogurt (1.44 mg GAE/g of yogurt, 4.00 mg TroloxE/g of yogurt, and 1.01 mg Fe(II)E/g of yogurt). Additionally, yogurts supplemented with fermented grapevine leaves demonstrated the potential to inhibit microbial growth without impairing the multiplication of lactic acid bacteria. [ABSTRACT FROM AUTHOR]

Crude oil spill has become a common phenomenon during oil production, transportation, and refining operations. It can occur in both land and water. While bioremediation and the use of cow dung for oil spill treatment have been established as an effective and environmentally friendly approach in the management of crude oil spill in land, little has been reported as it concerns water and most importantly, non-turbulent water bodies. The possibility of this application is of interest because non-turbulent water bodies have been reported to support the transport of petroleum hydrocarbon components down the water column, making the containment and treatment of polluted top surface insufficient. This paper reports on effort to treat an entire non-turbulent water body polluted with crude oil and with petroleum hydrocarbons diffusing through different depth of the water column. This was achieved by designing balls of cow dung with densities corresponding to that of the different depth strata of the water column, and then introduced into the polluted water. The balls then dissociate after a while, and filling the entire water volume with the cow dung particles, thus providing the necessary nutrients for microbial growth and activities across the entire water body. Samples of the water after treatment were then collected within a four (4) weeks post-treatment period and analysed using a GC-FID. At the end of the first week of treatment, the result showed a reduction of aliphatic hydrocarbons from 171.827mg/l, 98.641mg/l, 31.075mg/l and 18.675mg/l to 95.991mg/l, 33.914mg/l, 4.128mg/l, and 0.42mg/l and 1.12mg/l, 0.075mg/l, 0mg/l, and 0mg/l in the fourth week and at depths of 0.25m, 0.5m, 0.75m and 1.0m respectively. In the same vein, the aromatic hydrocarbons at the same depths, and after the first week of pre-treatment were 23.816mg/l, 12.942mg/l, 3.336mg/l and 0.962mg/l. At the end of the fourth week of post-treatment, negligible amount in all depths were recorded. These results show that the approach can be adopted in the treatment of oil spills in non-turbulent mangrove water bodies. [ABSTRACT FROM AUTHOR]

Up-flow sand filtration is an excellent alternative to point-of-use treatment for rural water supply. However, the sites and interval of microorganism growth in filter beds and the effect on bioclogging remain unknown. This study aimed to assess microorganism growth based on biological activity levels using Dissolved Oxygen (DO) consumption and Field Emission Scanning Electron Microscopy (FE-SEM) imaging in various zones of the filter bed. Additionally, pressure drop was monitored to evaluate bio-clogging. The results showed that microorganism activities differed within the 0.50 m up-flow sand filter bed during 8 weeks of acclimatization. Exponential growth started after day 35, and DO levels declined to a minimum of 2 mg/L at 0.10 m bed height (measured from the bottom) after day 46. At 0.30 m and 0.50 m height, the DO decreased to 0.8 mg/L and 0.3 mg/L after days 35 and 46, respectively. FE-SEM images confirmed microorganism growth on samples from 0.1 m after 4 weeks of acclimatization. Substantial growth was seen on samples of 0.10 and 0.30 m height at 8 weeks, while lesser growth was observed on samples of 0.50 m. The pressure drop showed no significant increase, signifying that clogging did not occur during the 135-day operational period. In conclusion, the up-flow configuration prevented bio-clogging in sand filters, reducing maintenance requirements. [ABSTRACT FROM AUTHOR]