Microbial Growth Research Articles

A combination of calcium hydroxide and sodium hydrosulphate controls pathogens causing environmental mastitis in recycled manure solids.

Recycled manure solids (RMS) are dried cow dung processed using a manure dewatering machine and subsequently sun-dried to ~ 20% moisture. Benefits of RMS include abundant availability, low cost, and eco-friendliness, but its use as bedding material for cows is hindered by a moisture content that promotes microbial growth. This in vitro study evaluated impacts of calcium hydroxide (CH; 5 and 7.5%) and sodium hydrosulphate (SHS; 6 and 8%), independently and in combinations, at various depths of RMS, on physicochemical and microbial properties. The CH-treated groups had increased pH and reduced moisture on Day 0. Incorporating 7.5% CH + 6% SHS at 15-20cm, and 7.5% CH + 8% SHS at all depths, effectively suppressed Escherichia coli and Klebsiella spp. Furthermore, a combination of 7.5% CH + 8% SHS at 20cm inhibited coliform growth, whereas 7.5% CH with 6% SHS inhibited Streptococcus spp. In conclusion, a combination of 7.5% CH with either 6 or 8% SHS at a depth of 15cm in RMS was particularly effective in controlling environmental mastitis-causing pathogens, specifically E. coli and Klebsiella spp.

Pressure-induced piezoelectric response for mitigating membrane fouling in surface water treatment: Insights from continuous operation and biofouling characterization

Organic fouling and biofouling represents a critical challenge encountered by the membrane-based water treatment process. Herein, a piezoelectric PVDF membrane (PEM), capable of generating electrical responses to hydraulic pressure stimuli, was synthesized and employed for mitigating the fouling in surface water treatment. The surface-hydrophobilized PEM demonstrated sensitive and enhanced underwater output performance in response to increasing transmembrane pressure (TMP) during constant-flux filtration, with signals reaching up to ∼800 mV at a TMP of ∼80 kPa. This in-situ piezoelectric response significantly reduced TMP growth in both short-term (1 h) and long-term (15 days) filtration trials, demonstrating a strong capability to mitigate membrane fouling. Moreover, continuous piezoelectric stimulation effectively inhibited microbial activity and the accumulation of extracellular polymeric substances (EPS) on PEM surface, surpassing the dominant electrokinetic repulsion mechanisms observed in short-term trials. Microbial community analysis suggests that this evolution is primarily due to the targeted impact of piezoelectric stimulation on microbial metabolic behavior. The piezoelectric-induced electrical microenvironment inhibited the growth of microbes associated with high EPS production while promoting the proliferation of electrically active microbes involved in biopolymer digestion. In addition, the PEM demonstrated enhanced permeate quality throughout the filtration process, with DOC and UV254 removal rates increasing from 11.7 % and 15.6 % initially to 28.6 % and 19.5 % by the 15th day, respectively. Given the performance and self-powered capability of PEM compared to current electrified antifouling methods that require an external power supply, these attributes are anticipated to hold practical significance in developing innovative and energy-efficient strategies for mitigating both organic fouling and biofouling.

Flash Vacuum Expansion of Maradol Papaya (Carica papaya L.) for Producing an Antioxidant-Potential Dairy Beverage Fermented by Limosilactobacillus fermentum J24

This study aimed to evaluate the fermentative capacity of the strain Limosilactobacillus fermentum J24 in a dairy beverage with papaya puree obtained through the flash vacuum expansion (FVE) process. Changes in phenolic content and antioxidant capacity during fermentation were investigated. Results showed that the dairy beverage with the control puree exhibited higher microbial growth than the FVE puree. Phenolic content increased during fermentation in both formulations. However, the antioxidant capacity was higher in the dairy beverage with control puree. A Pearson correlation analysis revealed a strong positive correlation between microbial load and antioxidant properties in the dairy beverage with control puree. In conclusion, the control puree promoted a higher growth of Limosilactobacillus fermentum J24 and better antioxidant properties in the papaya dairy beverage. These findings lay the groundwork for developing a potential functional dairy beverage based on papaya, effectively utilizing the fruit, reducing pollution, and adding value. This study also opens avenues for further research and development in functional dairy beverages, particularly those incorporating fruit-based ingredients.

The Antimicrobial Efficacy and Quality Changes in Pineapple Juice Treated with Natural Preservatives

The study investigated effects of natural preservatives on the quality of fresh pineapple fruit juice. The natural preservatives used are ginger, garlic, moringa seed and cloves and were processed into powder. The treatment of pineapple with the natural preservatives was at a concentration of 20% with 3 minutes dipping time. The enumeration and identification of microorganisms on the fresh pineapple fruit, shows that the total bacteria count was 1.8×105 colony forming unit per gram (CFU/g) and 4.6×103 CFU/g respectively. The identified bacteria are staphylococcus aureus and streptococcus spp and identified fungi were Aspergillus Niger, penicillin spp and Aspergillus perfrigens respectively. Moringa seed extract exhibited moderate antibacterial activity, with zones of inhibitions (ZOIs) of 16 mm against Staphylococcus aureus and 15 mm against Streptococcus spp. Garlic (GL) showed the least antibacterial activity among the natural preservative samples, with 9mm zones of inhibition against Staphylococcus aureus and 4 mm against Streptococcus spp. Clove extract displayed significant antibacterial activity, with 14 mm zones of inhibition against Staphylococcus aureus and 19 mm against Streptococcus spp. Ginger extract exhibited slight antibacterial activity, with zones of inhibition of 4 mm against both bacterial strains. Chemical composition of the treated pineapple juice result ranges from 0.77-0.865% TTA, 64.12-63.10 Vit C, 26.50-25.06 Brix Content,3.20-3.39 pH and 13.23-13.17 TSS respectively. The control (100% pineapple Juice) displayed balanced properties serving as an effective baseline3. Storage studies, ambient stored samples were analyzed at 0 day and 21 days intervals. All samples were subjected to standard analytical methods. Results showed increase in number of bacteria and fungi with increase in the number of days. The use of cloves, garlic, ginger, and moringa seeds as natural antimicrobial agents in pineapple juice is effective in controlling microbial growth, thus enhancing the safety and shelf life of the juice. These treatments also influence the chemical and sensory properties of the juice, contributing to consumer acceptability.

Unveiling fungal strategies: Mycoremediation in multi-metal pesticide environment using proteomics

Micropollutants, such as heavy metals and pesticides, inhibit microbial growth, threatening ecosystems. Yet, the mechanism behind mycoremediation of the pesticide lindane and multiple metals (Cd, Total Cr, Cu, Ni, Pb, Zn) remains poorly understood. In our study, we investigated cellular responses in Aspergillus fumigatus PD-18 using LC-MS/MS, identifying 2190 proteins, 1147 of which were consistently present under both stress conditions. Specifically, Cu-Zn superoxide dismutase and heat shock proteins were up-regulated to counter oxidative stress and protein misfolding. Proteins involved in intracellular trafficking, secretion, and vesicular transport; RNA processing and modification showed enhanced abundance and regulating stress response pathways. Additionally, haloalkane dehalogenase and homogentisate 1,2-dioxygenase played pivotal roles in lindane mineralization. Bioinformatics analysis highlighted enriched pathways such as Glyoxylate and dicarboxylate metabolism and Purine metabolism, that are crucial for combating adverse environments. We identified the hub protein 26 S proteasome regulatory subunit complex as potential biomarker and remedial targets for mycoremediation of wastewater, suggesting practical applications for environmental remediation.

Sensory testing and quality maintenance of hamburgers containing soybean meat

In the past few years, lifestyle-related diseases have been increasing, and meat intake has been linked to this increase. Therefore, in recent years, there have been attempts to use soybeans as a substitute for meat. Soybeans exhibit antioxidant and antimicrobial effects. Therefore, processing foods using soybeans may preserve food quality because the main factors causing food deterioration are oxidation and microbial growth. To verify the quality-retention effect of soybeans, we conducted a sensory test on hamburgers, the quality of which readily deteriorates over time. We investigated the percentage of soybean meat that would be acceptable in a hamburger and quality retention with the addition of different amounts of soybean meat. We found that hamburgers with soybean meat were accepted by more than half of the participants when the soybean meat content was ≤50%. In terms of changes over time in quality-related factors, the L- and b-values (lightness/brightness and yellowness/blueness, respectively) were higher, avalue (redness/greenness) was lower, and pH was higher in hamburgers that contained soybean meat than in those without added soybean meat. Furthermore, an increase in the bacteria count and peroxide content was suppressed in hamburgers containing soybean meat. The results indicate that hamburgers containing soybean meat are of higher quality than those made with 100% animal meat. The use of soybeans as a meat substitute in hamburgers can help mitigate the rise of lifestyle-related diseases linked to high meat consumption.

Effects of triple-layer chitosan/furcellaran mini-/nanoemulsions with oregano essential oil and LL37 bioactive peptide on shelf-life of cold/frozen stored pork loin

The aim of this study was to investigate the effect of triple-layer chitosan/furcellaran mini-/nanoemulsions with oregano essential oil and a bioactive peptide (LL37) on the microbiological quality and sensory properties of pork loins stored at 4 °C and −20 °C for 18 days and 6 months, respectively. Emulsions were applied using electrospraying technique. Multilayer mini-/nanoemulsions significantly inhibited the growth of microbes and improved sensory quality during storage. In the study, it was shown that coatings inhibited yeast and molds, total aerobic bacteria and Pseudomonas spp. by 1.24–3.46, 1.12–4.40, and 2.61–5.16 log cfu/g, respectively, compared to control at 4 °C. According to sensory analysis, the control and coated samples were deemed unacceptable after 9 and 18 days, respectively, at 4 °C. Therefore, the results of this study suggest that coatings can be effectively used for preservation of meat and meat products, prolonging food safety and quality, extending shelf-life and reducing food waste.

A comparative study on sequential green hybrid techniques (ultrasonication, microwave and high shear homogenization) for the extraction of date seed bioactive compounds and its application as an additive for shelf-life extension of Oreochromis niloticus

This study focuses on the extraction of bioactive compounds from date seeds using five polyol-based deep eutectic solvents (P-DESs) in combination with hybrid green extraction techniques, specifically microwave-assisted extraction (MAE), homogenization-assisted extraction (HAE), and ultrasound-assisted extraction (UAE). The optimization of these extraction techniques was achieved using P-DESs showing the highest efficiency for extracting date seed bioactive compounds using response surface methodology (RSM) and central composite design (CCD) approach. The optimized conditions from three green techniques were further applied in the form of hybrid green extraction techniques, involving six binary and three ternary methods, to assess the percentage increase in the extraction efficiency of date seed bioactive polyphenolics. Among the five P-DESs tested, choline chloride: ethylene glycol (ChCl:Eg) exhibited the highest extraction efficiency for recovering date seed phenolic compounds. Using ChCl:Eg as the P-DES, the highest extraction efficacy was found with MAE, followed by > HAE and > UAE. In addition, all hybrid extraction techniques showed higher extraction efficiencies than the single extraction methods. Notably, the binary hybrid techniques combining UAE and MAE (UMAE), HAE and MAE (HMAE) resulted in significantly higher recovery of bioactive compounds, with 52 % and 49 % increases in total phenolic content, respectively, compared to single extraction techniques. The lowest MIC and MBC of P-DES (ChCl:Eg) and date seed P-DES based extract recorded against all the tested bacterial strains was 40 % and 20 % respectively. Furthermore, the date seed extract from MAE was used to extend the shelf life of Oreochromis niloticus stored at 4 °C for 10 days. The results indicated that the date seed polyphenolic extract effectively inhibited microbial growth in Oreochromis niloticus during refrigerated storage, with the total bacterial count (TBC) of all the treated samples within the recommended acceptability limit of < 6 log CFU/g compared to the untreated samples, which showed a total bacterial count (TBC) > 6 log CFU/g. This study demonstrated that sequential hybrid techniques enhance and intensify the recovery of bioactive compounds more effectively than any single green technique.

Microbiological quality of vegan alternatives to dairy and meat products in England during 2022-3.

Plant-based alternatives to meat and dairy products have become increasingly popular in the UK. Despite a public perception that they have a relatively low microbiological risk, outbreaks of illness have been linked with these foods. This study aimed to assess the microbiological safety and quality of vegan alternatives to dairy and meat products available in England. Samples were collected between September 2022 and March 2023 from retail, production, and catering premises, and tested for a range of bacterial pathogens and hygiene indicators using standard procedures. A total of 937 samples were tested, of which 92% were of a satisfactory microbiological quality, 3% were borderline, and 5% were unsatisfactory. Those interpreted as unsatisfactory were due to elevated counts of Enterobacteriaceae and Escherichia coli (indicators of poor hygiene) rather than pathogenic microorganisms. Listeria monocytogenes was present in five samples of tofu, all from the same producer (all at counts of<100 CFU g-1), while other Listeria species were detected at counts of<20 CFU g-1 in two burgers and two 'vegan chicken' products. The majority of samples did not have pH and water activity values that would significantly contribute to preventing microbial growth: 62.4% had pH>5.0 and 82.4% had Aw>0.94. The majority of vegan products examined were of a satisfactory quality, but results demonstrate that microbiological control must be maintained using appropriate processing and storage temperatures, and application of a safe length of shelf life.

Characteristics of organic amendments induce diverse microbial metabolisms for exogenous C turnover in Mollisols

The response of microbial community to organic amendments is closely related to the amendment-derived carbon (C) turnover, which in turn influences the enhancement of soil organic C, including the quantity and quality. The objective of this study was to quantify the decomposition and retention of exogenous C derived from amendments, and to identify the microbial regulatory mechanisms of exogenous C turnover in response to the characteristics of organic amendments. The 13C-labelled glucose, straw and biochar, characterizing organic amendments with high, medium and low labilities, respectively, were used to conduct a 90-day incubation experiment, in conjunction with stable isotope probing technology and amino sugar molecular biomarkers. It was found that the cumulative mineralization of amendment-derived C increased with increasing the corresponding lability of organic amendment, and the decompositions of the added glucose, straw and biochar, expressed as a percentage of the initially added C, were 53.6 %, 37.0 %, and 0.6 %, respectively. Among all treatments, the addition of straw significantly enhanced the total dissolved organic C (DOC) concentration and its ratio to total organic C by increasing the input of exogenous DOC and reducing the decomposition of native soil DOC. The exogenous C use efficiency by microorganisms was significantly enhanced with decreasing the amendment lability, and showed a positive correlation with the total amendment-derived C. However, the microbial growth efficiency was the highest when straw was added, and was closely related to the concentration of amendment-derived DOC. Different functional groups of soil microbes exhibited distinct capacities to metabolize various organic amendments. Generally, the incorporation of amendment-derived C into microbial biomass was significantly affected by fungi and gram-positive (G+) bacteria, while the relative contributions of microbial communities incorporating amendment-derived C into necromass were decreased in the order of gram-negative (G−) bacteria > fungi > actinomycetes > G+ bacteria. From the perspective of microbial metabolism, the larger incorporations of exogenous C into microbial biomass and necromass were observed in the soil with mediumly labile amendment, which contributed to enhance the quantity and quality of organic C in soil. These results would be informative to optimize the organic amendment strategy for integrated soil fertility management.

Bioactive Potential of Algae and Algae-Derived Compounds: Focus on Anti-Inflammatory, Antimicrobial, and Antioxidant Effects.

Algae, both micro- and macroalgae, are recognized for their rich repository of bioactive compounds with potential therapeutic applications. These marine organisms produce a variety of secondary metabolites that exhibit significant anti-inflammatory, antioxidant, and antimicrobial properties, offering promising avenues for the development of new drugs and nutraceuticals. Algae-derived compounds, including polyphenols, carotenoids, lipids, and polysaccharides, have demonstrated efficacy in modulating key inflammatory pathways, reducing oxidative stress, and inhibiting microbial growth. At the molecular level, these compounds influence macrophage activity, suppress the production of pro-inflammatory cytokines, and regulate apoptotic processes. Studies have shown that algae extracts can inhibit inflammatory signaling pathways such as NF-κB and MAPK, reduce oxidative damage by activating Nrf2, and offer an alternative to traditional antibiotics by combatting bacterial infections. Furthermore, algae's therapeutic potential extends to addressing diseases such as cardiovascular disorders, neurodegenerative conditions, and cancer, with ongoing research exploring their efficacy in preclinical animal models. The pig model, due to its physiological similarities to humans, is highlighted as particularly suitable for validating the bioactivities of algal compounds in vivo. This review underscores the need for further investigation into the specific mechanisms of action and clinical applications of algae-derived biomolecules.

The influence of storage conditions on hygiene condition and eicosapentaenoic acid oxidation in Nannochloropsis algae for sustainable food supply.

Nannochloropsis algae contain approximately 20% polyunsaturated fatty acids (PUFA) and hold significant potential for high-quality eicosapentaenoic acid (EPA) food industrialization. However, EPA in Nannochloropsis sp. is prone to oxidation, and microbial growth is a critical factor affecting the shelf life of fresh food. Storage composition and temperature are primary factors influencing microbial growth, yet these aspects are not fully understood. This study investigates the effects of temperature and encapsulation on EPA content in nano-products over time. Nano-powder and nanobeads derived from Nannochloropsis sp. served as raw materials. Additionally, changes in aerobic plate counts and coliform groups were monitored. The results indicated that nanobeads, due to their more complex processing and less mature packaging, were more susceptible to coliform contamination compared to nano-powder. In terms of EPA stability, nanobeads exhibited a longer storage life than nano-powder. The oxidation rate of both nano-powder and nanobeads was faster at 37 °C than at 25 °C. These findings can inform general shelf life estimation, rapid detection of total lipid content in nano-products and macro extraction of nano-oil. Moreover, they have significant implications for delaying EPA oxidation in nano-products and improving hygienic quality control for microbial detection. © 2024 Society of Chemical Industry.

Carbon‐to‐nitrogen stoichiometry of organic amendments regulates microbial biomass growth and nitrogen mineralization in soil

AbstractThe carbon‐to‐nitrogen (C:N) ratio of organic amendments regulates nutrient cycling in soil through its influence on microbial activity. Where an organic amendment has a C:N ratio sparingly higher than that of soil microbes (C:N ratio 6.7—8.7), meeting microbial requirements of carbon and nitrogen may promote microbial biomass growth and nitrogen mineralization. Here we sought to understand the microbial response to the addition of organic amendments with varying C:N ratios and subsequent changes in nitrogen mineralization and plant nitrogen uptake. Dried insect larvae, beef feedlot manure and mixtures of beef feedlot manure with insect larvae or sugarcane residue were used as soil amendments to create a gradient of molar C:N ratios (Cm:Nm) ranging from 6 to 28. An untreated control treatment with a C:N ratio of 17 was also included. Sorghum (Sorghum bicolor L.) was grown in control and organic matter amended soils for 20 days after germination. The mixture of beef feedlot manure and insect larvae treatment (Cm:Nm = 9.7) had on average 68% higher microbial biomass compared with the other treatments. Beef feedlot manure with Cm:Nm ratio of 11 did not influence microbial biomass growth. The concentration of mineral nitrogen was highest in the insect larvae (Cm:Nm = 6) treatment, where 23% of the plant nitrogen was derived from the insect larvae as indicated by the δ15N of plant dry matter. We observed both carbon and nitrogen contents in the organic amendment determine microbial biomass growth and nitrogen mineralization in soil. The results presented here demonstrate that microbial response to organic amendments determines the availability of mineral nitrogen in soil.

Modeling microbial growth based on time-dependent kinetic mechanisms of digestion and passage in the ruminoreticulum

The original Cornell Net Carbohydrate and Protein System (CNCPS) model, which was developed in 1992 and revised in 2004, included a rumen submodel with a set of equations that were algebraically programmed in a spreadsheet to predict bacterial N flow to the caudal tract of cattle. In this study, we propose a modification to the original CNCPS rumen submodel based on mathematical concepts that simulate the flow paths of solids and liquid in the rumen, which are known to be essential factors affecting rumen fermentation and microbial growth. This modification allows the quantification of the impact of aging mechanisms on the availability of both soluble and insoluble substrates for microbial growth in the rumen. Additionally, a correction has been proposed on peptide uptake by rumen bacteria. Literature data were used to evaluate the model adequacy of CNCPS versions 1992 and 2004, along with the proposed model, to determine their ability to predict bacterial N flow. The proposed model more accurately predicted the variable of interest, but there was an overall underprediction bias. Despite the rightful critics of the ability of mechanistic models to predict microbial crude protein flow from the rumen, the 1992 and 2004 versions of the CNCPS and the proposed modifications implemented within the CNCPS framework led to predictions that agreed with observational data at a discordance rate of 0.05, tolerance probabilities <0.001 for versions 1992 and 2004, and a tolerance probability equal to 0.13 for the proposed model given a sample size n=39. Therefore, the proposed modifications might improve the ability of CNCPS-based models to predict the bacterial N flow from the rumen, thereby resulting in improved predictive performance compared to the original CNCPS model. Thus, it seems that models built on time-dependent kinetics of food particles and fluid are more fitting than steady-state ones to predict bacterial N flow to the caudal tract.

Influence of various organic nutrient management technologies on microbial abundance, growth, and yield of rice (Oryza sativa L.) under field conditions

A field study (three years) was carried out to evaluate the outcome of various organic nutrient management technologies including farmyard manure (FYM) and poultry manure (PM) integrated with chemical fertilizers for microbial dynamics and growth and yield of rice at Experimental Farm of Nuclear Institute of Agriculture (NIA), Tandojam, Sindh, Pakistan. The most broadly grown rice variety, NIA-Shandar was selected for this study. The experiment involved integrating organic technologies, specifically Farm Yard Manure (FYM) and Poultry Manure (PM), each applied at 10 tons per hectare. These organic technologies were combined with varying levels of inorganic fertilizers: half (60 kg N ha-1 and 45 kg P2O5 ha-1) and full (120 kg N ha-1 and 90 kg P2O5 ha-1) recommended doses. Additionally, zinc was applied at 10 kg ha-1. The study employed a randomized complete block design (RCBD) with three replications to assess treatment effects. Both organic technologies perform better for microbial dynamics and rice growth and yield enhancement either alone technology or combined with chemical fertilizers during three rice seasons. The maximum general microbial abundance (9.70 log10 CFU g soil-1), N2 fixing (7.37 log10 CFU g soil-1), P solubilizing (7.97 log10 CFU g soil-1) and Zn solubilizing(6.75 log10 CFU g soil-1) population was recorded in FYM alone or with half N and P2O5 fertilizer application. The highest plant height (106 cm), tiller numbers(17.10), panicle numbers (26.53), panicle length (26.32 cm), one thousand grainweight (26.53 g) and rice grain yield (7.92 t ha-1) were perceived in FYM with full rate N and P2O5 fertilizer application. Both technologies along with chemical fertilizer induced soil properties and soil nutrients which reflected to increase soil microbial abundance and growth and yield of rice however, FYM showed higher potential than poultry manure during the three years rice cultivation seasons. Hence, it was indicated that a significant contribution to the development of sustainable agricultural technologies that prioritize soil health,environmental stewardship, and food security.

Response processes to water quality changes driven by the dynamic regeneration of the surface microlayer film in slow-flowing freshwater bodies

The freshwater surface microlayer film (SMF) is a dynamically evolving micro-ecosystem closely related to water quality and microbial growth in water. However, the mechanisms of dynamic regeneration of SMF after their destruction and their impacts on the aquatic environment are still largely unknown. Herein, we modeled the dynamic processes of SMF destruction and recovery in the natural environment by constructing a water-SMF ecosystem. Chemical and biological changes in the dynamic regeneration of SMF were investigated. The results showed that the dynamic regeneration of SMF was very fast, with a regeneration thickness of up to 300±50 μm in two days, and at the same time, it would rapidly enrich organic matter and Fe ions. In addition, the cyclic dynamic regeneration process of SMF is significantly correlated with the surge metabolic growth of microorganisms associated with organic matter metabolism (e.g., Methylophilus, Nevskia) and iron-redox-associated (e.g., Curvibacter). The experimental results suggest that the microbial-mediated process of iron-organic matter coupled oxidation-reduction in SMF may be another important mechanism driving water quality changes. Overall, our study provides valuable theoretical guidance for predicting changes in water quality in slow-flowing water bodies.

Curcumin-mediated photodynamic treatment to extend the postharvest shelf-life of strawberries.

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.

Eco-Friendly Innovation: Crafting Bio-Environmental Rice Husk Board for Sustainable Living

Background: The growing focus on environmental sustainability and safety has heightened the demand for eco-friendly household materials. This study explores the development of a bio-based board using rice husk (RH), assessing its properties and potential for diverse applications. Methods: The board was formulated using 30 g RH powder, 2 ml glycerol, 4 g agar, 3 g calcium propionate, and 100 ml water. The study involved visual and textural evaluation, physical property testing, and microbial growth assessment. Practical utility was examined through the fabrication of various objects including boxes and candle bases, and material adaptability was tested by varying RH concentrations and additives. Results: The RH boards, with equal proportions of RH and RH powder, exhibited light weight and good physical characteristics. Microbial growth was limited to 39% under conditions of 37 °C and 95% humidity. The boards were moldable, with a smooth, easily colorable surface post-sanding, demonstrating shape stability and flame retardancy under prolonged heat exposure. Furthermore, the material demonstrates good compatibility; varying RH ratios, colorants, and preservatives yield different appearance effects and characteristics. Conclusions: This study successfully developed a sustainable, safe, and versatile RH board, showcasing significant commercial potential and suitability as an innovative eco-friendly material.

Recovery of Soil Microbial Metabolism After Rewetting Depends on Interacting Environmental Conditions and Changes in Functional Groups and Life History Strategies.

Climate change is causing an intensification of soil drying and rewetting events, altering microbial functioning and potentially destabilizing soil organic carbon. After rewetting, changes in microbial community carbon use efficiency (CUE), investment in life history strategies, and fungal to bacterial dominance co-occur. Still, we have yet to generalize what drives these dynamic responses. Here, we collated 123 time series of microbial community growth (G, sum of fungal and bacterial growth, evaluated by leucine and acetate incorporation, respectively) and respiration (R) after rewetting and calculated CUE = G/(G + R). First, we characterized CUE recovery by two metrics: maximum CUE and time to maximum CUE. Second, we translated microbial growth and respiration data into microbial investments in life history strategies (high yield (Y), resource acquisition (A), and stress tolerance (S)). Third, we characterized the temporal change in fungal to bacterial dominance. Finally, the metrics describing the CUE recovery, investment in life history strategies, and fungal to bacterial dominance after rewetting were explained by environmental factors and microbial properties. CUE increased after rewetting as fungal dominance declined, but the maximum CUE was explained by the CUE under moist conditions, rather than specific environmental factors. In contrast, higher soil pH and carbon availability accelerated the decline of microbial investment in stress tolerance and fungal dominance. We conclude that microbial CUE recovery is mostly driven by the shifting microbial community composition and the metabolic capacity of the community, whereas changes in microbial investment in life history strategies and fungal versus bacterial dominance depend on soil pH and carbon availability.

Enhanced air filtration and ammonia sensing with cellulose nanofibers-based triboelectric nanogenerators under harsh environments

Fire accidents often occur in environments characterized by severe air pollution, toxic gas emissions, and microbial growth, creating significant challenges for developing multifunctional portable healthcare devices. These devices must achieve high filtration efficiency, minimal pressure drop, and the capability to provide early warnings of toxic gas leaks. Triboelectric nanogenerators present a sustainable solution as self-powered energy converters for advanced healthcare applications. In this study, we grafted Ti3C2Tx/MoS2 nanohybrid materials, which form Schottky heterojunctions, onto cellulose diacetate using tetraethyl orthosilicate, followed by electrospinning to produce nanofibrous films. When paired with a negatively charged material, the resulting device achieved an optimal balance with a low-pressure drop (52 Pa) and high filtration efficiency (98.72 % for PM0.3). It also demonstrated exceptional stability under high-temperature and high-humidity conditions. Notably, the device maintained rapid sterilization within 15 min and consistent filtration performance even after multiple washes. Furthermore, the device exhibited precise detection of trace amounts of NH3 (0.1 ppm) and demonstrated a rapid response, achieving an 86 % response rate within 2 s for 100 ppm NH3, providing an early warning 28 s faster than commercial NH₃ monitors. This study introduces a novel approach to the development of multifunctional, self-powered, wearable medical devices that offer high-efficiency air filtration and sterilization, breath monitoring, and rapid toxic gas leakage detection in harsh environments.