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The rise of antimicrobial-resistant microorganisms (AMR) poses a significant global challenge to human health and economic stability. In response, various scientific communities are seeking safe alternatives to antibiotics. This study comprehensively investigates the antibacterial effects of red dye derived from Monascus purpureus against three bacterial pathogens: Salmonella typhimurium ATCC14028, Escherichia coli ATCC8739, and Enterococcus faecalis ATCC25923. The dye was extracted from the Monascus purpureus ATCC16436 strain, using 1 mg of red dye in 1 ml of DMSO to achieve a concentration of 1000 µg/ml. The chemical profile of the red dye extract was analyzed using GC-MS analysis, confirming the presence of several bioactive antimicrobial compounds, including aspidospermidin-17-ol, 1-acetyl-16-methoxy, octanoic acid, and hexadecanoic acid methyl ester. The extract was tested against the bacterial strains at varying concentrations to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The results demonstrated significant antibacterial activity, with the highest MIC and MBC values of 6.25/12.5 µg/ml against S. typhimurium. The antibacterial activity of the red dye was compared to five conventional antibiotics using the disc diffusion method, revealing superior effectiveness, particularly against S. typhimurium, with an inhibition zone measuring 20 ± 0.22 mm. Scanning electron microscopy was employed to explore the mechanism of action of the red dye extract, highlighting its impact on bacterial plasma membrane permeability and its interference with cellular energy production. These findings suggest that the Monascus purpureus-derived red dye extract represents a promising natural alternative to conventional antibiotics, demonstrating potent antibacterial activity and potential as a novel therapeutic agent in combating antimicrobial resistance.

Afforestation projects on saline land, using Eucalyptus trees and ectomycorrhizal fungi, are crucial for restoring affected areas and promoting ecological and economic benefits, particularly in saline-affected areas. This study was conducted to isolate Pisolithus sp. and estimate its potential to improve the growth performance of Eucalyptus globulus seedlings under salt-stress conditions. Pisolithus sp. was isolated from mature sporocarps and identified through 18S rDNA. Pisolithus sp. was evaluated for its response to varying pH values, temperatures, and salinity levels. A pot experiment was conducted to assess the Pisolithus strain's effectiveness in reducing soil salinity's impact on the growth of Eucalyptus globulus seedlings in sandy soil. The identified Pisolithus tinctorius with an accession number of OM125275 revealed the highest mycelium dry weight of 0.09 g/100 ml medium at pH 5.8, 0.08 g/100 ml medium at 28 °C, and 0.12 g/100 ml medium at 4% NaCl. Eucalyptus globulus seedlings inoculated with Pisolithus tinctorius demonstrated significant improvement in most parameters compared to non-mycorrhizal (control) seedlings under salt stress. The seedlings inoculated with Pisolithus tinctorius and irrigated with 6 dS/m saline water revealed the highest shoot height (55.670 cm), root length (42.33 cm), shoot fresh weight (6.44 g/plant), root fresh weight (1.84 g/plant), shoot dry weight (2.37 g/plant), and root dry weight (0.810 g/plant) when compared to all treatments. Our findings suggest that selecting appropriate fungal strains is crucial for improving plant performance in saline conditions.

A Novel cold-active chitin deacetylase from Shewanella psychrophila WP2 (SpsCDA) was overexpressed in Escherichia coli BL21 and employed for deacetylation of chitin to chitosan. The produced chitosan was characterized, and its antifungal activity was investigated against Fusarium oxysporum. The purified recombinant SpsCDA appeared as a single band on SDS-PAGE at approximately 60 kDa, and its specific activity was 92 U/mg. The optimum temperature and pH of SpsCDA were 15 °C and 8.0, respectively, and the enzyme activity was significantly enhanced in the presence of NaCl. The bioconversion of chitin to chitosan by SpsCDA was accomplished in 72 h, and the chitosan yield was 69.2%. The solubility of chitosan was estimated to be 73.4%, and the degree of deacetylation was 78.1%. The estimated molecular weight of the produced chitosan was 224.7 ± 8.4 kDa with a crystallinity index (CrI) value of 18.75. Moreover, FTIR and XRD spectra revealed the characteristic peaks for enzymatically produced chitosan compared with standard chitosan, indicating their structural similarity. The produced chitosan inhibited spore germination of F. oxysporum with a minimum inhibitory concentration (MIC) of 1.56 mg/mL. The potential antifungal effect of chitosan is attributed to the inhibition of spore germination accompanied by ultrastructural damage of membranes and leakage of cellular components, as evidenced by transmission electron microscopy (TEM), and accumulation of reactive oxygen species (ROS) that was confirmed by fluorescence microscopy. This study shed light on the cold-active chitin deacetylase from S. psychrophila and provides a candidate enzyme for the green preparation of chitosan.

Disease emergence has become a main limiting factor in aquaculture. The massive application of antibiotics as disease therapy has been resulting in the adverse effects of environment, host and consumers. Ethyl acetate leaf extract of A.marina has recorded high biological activity. Crude extract has showed the antibacterial activity of range 3.2 ± 0.8 mm against B.subtilis to 5.7 ± 0.7 mm against A.hydrophila, DPPH; 15.9 ± 0.7 AAE µg/ml to 79.4 ± 1.0 AAE µg/ml and FRAP; 6.4 ± 1.3 AAE µg/ml to 127.3 ± 1.3 AAE µg/ml. The mass spectral results revealed the presence of thioacetic acid, methyl thio ethane, 1-Fluoro-2-propanone, Isopropanethiol. CAT and SOD levels of ethyl acetate extract treated fingerlings was: crude; 15.5 ± 1.0 units/mg of protein and 13 ± 0.9 units/mg of protein, purified 18.3 ± 0.5 units/mg of protein and 16.9 ± 1.1 units/mg of protein.

Coconut oil is eatable oil with many nutritional and cosmetic applications. In this investigation coconut oil was subjected to 0 to 5 L/min of ozone for 3 h and the chemical composition of both crude and ozonized oil was valued via Gas Chromatography-Mass Spectrometry (GC-MS). Some biological tests were done including antibacterial action versus Helicobacter pylori, anti-biofilm activity versus H. pylori, anti-hemolytic activity in the existence of H. pylori, anti-Alzheimer action, and cytotoxic effect towards A-413 cancer cell line to determine the activity of coconut oil and upon exposure to ozone. Fifteen compounds were detected in the coconut oil crude and ozonized oils where the fatty acid esters were the most common molecules in crude coconut oil, whereas alkenes were the most predominant compounds in ozonized coconut oil. A slight elevation of antibacterial action towards H. pylori from 23.0 ± 0.1 to 28.2 ± 0.5 mm was displayed upon exposure of the coconut oil to ozone. Both crude and ozonized coconut oil showed a bactericidal effect with MICs = 62.5 ± 0.1, 125.0 ± 0.2 µg/mL and MBCs = 15.62 ± 0.2, 31.25 0.2 µg/mL for crude and ozonized oil, respectively. A significant elevation in anti-biofilm activity was found upon using 25% of MBCs of ozonized oil relative to crude oil. A dramatic rise was observed in anti-hemolytic activity upon using 25 and 75% of MICs of ozonized oil relative to crude one. A notable elevation of anti-Alzheimer impact was evident upon exposing coconut oil to ozone. Besides, the cytotoxic impact towards A-431 cells was slightly increased after exposing the oil to ozone. The current results suggest a new technique to expose coconut oil to ozone to improve some of its in vitro pharmaceutical applications.

Extracts of medicinal seeds can be used to synthesize nanoparticles (NPs) in more environmentally friendly ways than physical or chemical ways. For the first time, aqueous extract from unexploited grape seeds was used in this study to create Se/ZnO NPS utilizing a green technique, and their antimicrobial activity, cytotoxicity, antioxidant activities, and plant bio stimulant properties of the economic Vicia faba L. plant were evaluated. Se/ZnO NPS is characterized by SEM and TEM images, FTIR, and XRD. Through the well diffusion assay and the scavenging of 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical experiment, biogenic Se/ZnO NPs demonstrated their antibacterial and antioxidant activities. The nanomaterial compound showed the highest inhibitory effects of 99.7, 55.63, 16.91, 10.25, 6.61, 3.83, 3.00, and 2.59%, respectively, against the cervical carcinoma (SKOV3 cells) cell line at conc of 7.81, 15.62, 31.25, 62.5, 125, 250, 500, and 1000 µg/ml, respectively, with IC50 values at 20.31 µg, resulting in 50% cell death. This study demonstrated the value of bimetallic nano-fertilizers Se/Zn in promoting faba bean development, yield features, and metabolite contents (protein, phenol, carbs, and pigments). These fertilizers are probably also advantageous for other crops. When applied in contrast to the control, 100 ppm of biological nano-Se/ZnO may generally result in the best growth and yield of faba beans. Further research is needed on the ecological aspect of biological nanofertilizers in addition to the economic one.

Antibiotics become less effective in treating infectious diseases as resistance increases. Staphylococcus aureus is a global problem due to its ability to form biofilms and resistance mechanisms. Phage endolysin is one of the most promising methods for combating antibiotic resistance. ZAM-MSC chimeric endolysin has three domains derived from SAL1 and lysostaphin, which target the peptide bridge of peptidoglycan. In this study purified ZAM-MSC (with yield of 30 mg/lit) had bactericidal activity against methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) at low concentrations (2.38 μg/ml and 1.88 μg/ml, respectively). The antibacterial spectrum revealed that ZAM-MSC was active against diverse Staphylococci. it has maintained 100% stability after 24 h incubation in pH 5 to 10 against S. aureus, as well as demonstrated significant thermostability and maintained nearly its full activity at different temperatures (4-42 °C) up to 1 day of incubation. The anti-biofilm activity of various concentrations of ZAM-MSC against MSSA and MRSA biofilms was not dose-dependent, and antibiofilm activity was observed even at low concentrations (14 μg/ml). Further, the molecular dynamics simulations demonstrated that the ZAM-MSC chimer and its parent proteins remained dynamically stable, showing similar flexibility despite the size and hydrogen bond number differences. In conclusion, the study reveals that chimeric ZAM-MSC is a distinctive enzyme with exceptional biochemical properties and rapid lytic activity against Staphylococci.

Functional fermentation strains were isolated and screened from traditional fairy beans in northern Anhui. Through technical identification, Bacillus subtilis SXD06 was determined to be the superior fermentation strain, while Wickerhamomyces anomalus YE006 was identified as the optimal aroma-producing yeast. Utilizing single-factor experiments and response surface optimization, a Central Composite Design fermentation and blending model was established. The optimal fermentation conditions were determined to be: an inoculation amount of 1.1% for Bacillus subtilis SXD06, an inoculation amount of 4.2% for Wickerhamomyces anomalus YE006, and a fermentation temperature of 34 °C, Fermentation lasted 84.2 h. SDS-PAGE electrophoresis comparison between control and sample groups indicated effective fermentation, with most fairy beans converting to amino acids. Optimal conditions were identified as 5.5% salt, 0.26% star anise powder, 0.25% cinnamon, 1.5% pepper, 4.5% edible alcohol, and 0.28% fragrant leaves. The sensory evaluation of soybean products produced under the specified conditions yielded the highest scores. This study offers robust technical support for the development of low-ammonia, high-quality fairy bean products that align with consumer preferences.

Reducing greenhouse gas (GHG) emissions from livestock is a crucial step towards mitigating the impact of climate change and improving environmental sustainability in agriculture. This study aimed to evaluate the effects of Yucca schidigera extract, chitosan, and chitosan nanoparticles as feed additives on in vitro GHG emissions and fermentation profiles in ruminal fluid from bulls. Total gas, CH₄, CO, and H₂S emissions (up to 48 h), rumen fermentation profiles, and CH₄ conversion efficiency were measured using standard protocols. The experiments involved supplementing 0.25, 0.5, and 1 mL/g dry matter (DM) of additives in different forages (alfalfa hay, corn silage, and oats hay). The chemical composition of forage showed suitable levels of DM, ash, crude protein, acid detergent fiber, neutral detergent fiber, lignin, and metabolizable energy. The addition of these supplements increased asymptotic gas production across all forages while simultaneously reducing CH₄, CO, and H₂S emissions, though the extent of reduction varied depending on forage type. Moreover, the treatments improved fermentation profiles, including pH and dry matter digestibility, and significantly influenced CH₄ conversion efficiency (CH₄:ME, CH₄:OM, and CH₄:SCFA; P < 0.05). These results underscore the potential of Y. schidigera extract, chitosan, and chitosan nanoparticles as effective strategies for mitigating GHG emissions from ruminants given these promising in vitro findings. Further in vivo studies are recommended to validate their efficacy under real-world conditions, which could pave the way for practical applications in the field.