Gradual depletion in soil nutrients has affected soil fertility, soil nutrients, and the activities of soil enzymes. The applications of multifarious rhizobacteria can help to overcome these issues, however, the effect of co-inoculation of plant-growth promoting rhizobacteria (PGPR) and biochar on growth andnutrient levelsin soybean and on the level of soil nutrients and enzymes needs in-depth study. The present study aimed to evaluate the effect of co-inoculation of multifarious Bradyrhizobium japonicum USDA 110 and Pseudomonas putida TSAU1 and different levels (1 and 3%) of biochar on growth parameters and nutrient levelsin soybean and on the level of soil nutrients and enzymes. Effect of co-inoculation of rhizobacteria and biochar (1 and 3%) on the plant growth parameters and soil biochemicals were studied in pot assay experiments under greenhouse conditions. Both produced good amounts of indole-acetic acid; (22 and 16 µg mL⁻¹), siderophores (79 and 87%SU), and phosphate solubilization (0.89 and 1.02 99 g mL⁻¹). Co-inoculation of B. japonicum with P. putida and 3% biochar significantly improved the growth and nutrient content ofsoybean and the level of nutrients and enzymes in the soil, thus making the soil more fertile to support crop yield. The results of this research provide the basis of sustainable and chemical-free farming for improved yields and nutrients in soybean and improvement in soil biochemical properties.

Arbuscular mycorrhizal fungi (AMF) inoculation and biochar amendment has been reported to improve the growth of several crop plant; however, their role in stress amelioration individually as well as in combination has not been worked out. Limited information is available about the synergistic use of biochar and Arbuscular Mycorrhizal Fungi (AMF). Here, we investigated the synergistic effect of biochar and AMF on plant development, root architecture, the physiological performance of fenugreek (Trigonella foenum-graecum), and soil enzymatic activities. Biochar and AMF were shown to have a considerable effect on plant height, according to the data (53.3 and 66.6%, respectively), leaf number (22.5 and 45.1%), total root length (19.8 and 40.1%), root volume (32.1 and 71.4%), chlorophyll a content (26.0 and 17.8%), chlorophyll b content (50.0 and 28.9%), total chlorophyll content (30.0 and 18.1%), and carotenoid content (60.0 and 48.0%) over the control treatment. There was a considerable increase in plant height when biochar and AMF were combined together by 80.9%, total root length by 68.9%, projected area by 48.7%, root surface area by 34.4%, root volume by 78.5%, chlorophyll a content by 34.2%, chlorophyll b content by 68.4%, total chlorophyll content by 44.5%, and carotenoid content by 84.0% compared to the control. Our results recommend that the combination of biochar and AMF is advantageous in fenugreek growth, microbial biomass, and soil enzyme activities.

Quorum sensing inhibitor (QSI) has been attracting attention as anti-virulence agent which disarms pathogens of their virulence rather than killing them. QSI marking cyclic peptide-mediated QS in Gram-positive bacteria is an effective tool to overcome the crisis of antibiotic-dependent chemotherapy due to the emergence of drug resistance strain, e.g., methicillin resistant Staphylococcus aureus (MRSA) and Vancomycin resistant Enterococci (VRE). From a semi-large-scale screening thus far carried out, two Epoxide compounds, Ambuic acid and Synerazol, have been found to efficiently block agr and fsr QS systems, suggesting that the Epoxide group is involved in the mode of action of these QSIs. To address this notion, known natural Epoxide compounds, Cerulenin and Fosfomycin were examined for QSI activity for the agr and fsr systems in addition to in silico and SAR studies. As a result, most of investigated Epoxide containing antibiotics correlatively interfere with QSI activity for the agr and fsr systems under sublethal concentrations.

Toluene and other monoaromatic compounds are released into the environment particularly saline habitats due to the inappropriate disposal methods of petroleum products. Studying the bio-removal strategy is required to clean up these hazardous hydrocarbons that threaten all ecosystem life using halophilic bacteria with higher biodegradation efficiency of monoaromatic compounds as a sole carbon and energy source. Therefore, sixteen pure halophilic bacterial isolates were obtained from saline soil of Wadi An Natrun, Egypt, which have the ability to degrade toluene and consume it as the only source of carbon and energy. Amongst these isolates, isolate M7 exhibited the best growth with considerable properties. This isolate was selected as the most potent strain and identified based on phenotypic and genotypic characterizations. The strain M7 was belonging to Exiguobacterium genus and founded to be closely matched to the Exiguobacterium mexicanum with a similarity of 99%. Using toluene as sole carbon source, strain M7 showed good growth at a wide range temperature degree (20–40ºC), pH (5–9), and salt concentrations (2.5–10%, w/v) with optimal growth conditions at 35ºC, pH 8, and 5%, respectively. The biodegradation ratio of toluene was estimated at above optimal conditions and analyzed using Purge-Trap GC-MS. The results showed that strain M7 has the potentiality to degraded 88.32% of toluene within greatly short time (48 h). The current study findings support the potential ability to use strain M7 as a biotechnological tool in many applications such as effluent treatment and toluene waste management.

Agro-industrial residues such as palm date waste (PDW) represent an abundant and underutilized carbon source with significant potential for microbial valorization. Oleaginous yeasts, known for their high lipid-accumulating capacity, offer a sustainable route for single-cell oil (SCO) production, particularly in arid regions where PDW is prevalent. However, the efficient bio-conversion of such lignocellulosic feedstocks requires robust microbial strains and optimized fermentation strategies. In this study, an isolated strain of Rhodotorula glutinis KAEC-61 from mangrove sediments was selected from several isolates for its superior lipid-producing ability. Initial flask-level screening under non-optimized conditions yielded 1.9 ± 0.10 g/L biomass and 0.56 ± 0.06 g/L lipid titer (29% lipid content). Optimization via the one-variable-at-a-time (OVAT) method increased biomass and lipid production by 4.4-fold and 6-fold, respectively, reaching 8.42 ± 0.52 g/L biomass and 3.37 ± 0.55 g/L lipid titer (40% lipid content). Further enhancement through Plackett–Burman and Box–Behnken designs led to 11-fold and 16.7-fold improvements, achieving 20.95 ± 1.2 g/L biomass and 9.35 ± 0.35 g/L lipid titer (44.6% lipid content) from 53.7 ± 0.29 g/L xylose in a 7-L bioreactor under controlled pH. A fed-batch fermentation strategy further elevated performance to 27.0 ± 1.08 g/L biomass and 13.0 ± 0.36 g/L lipid titer (48.1% lipid content). When xylose was replaced with PDW hydrolysate, lipid production increased to 14.7 ± 1.14 g/L titer (54.4% lipid content), representing a 26.3-fold improvement over initial conditions. Fatty acid profiling revealed a composition dominated by oleic and linoleic acids, with over 54% comprising unsaturated fatty acids. Notably, γ-linolenic acid, cis-10-pentadecenoic acid, and cis-11-eicosenoic acid rare fatty acids with distinct physicochemical and nutraceutical properties were detected, highlighting the strain’s potential for specialty lipid production. This study establishes a scalable, statistically optimized bioprocess for PDW valorization using an environmental isolate of R. glutinis, contributing to circular bioeconomy strategies for sustainable microbial lipid biomanufacturing.