Abstract Fungal contamination of stored grains by Aspergillus, Penicillium, and Fusarium threatens food security and public health. Grain preservatives are essential to maintain product quality and safety. This study investigated sunflower oil (Helianthus annuus), reported to be rich in fatty acids, tocopherols, phytosterols, and phenolic antioxidants, as an antifungal alternative to conventional preservatives. Non-refined sunflower oil obtained by laboratory extraction (SO) showed broad-spectrum activity against all 21 grain-relevant filamentous fungi tested, with minimum inhibitory concentration (MIC) values of 0.05% to 0.4%. In contrast, commercial sunflower oil (CSO) was inactive (MIC > 50%), indicating that antifungal efficacy depends on extraction and refinement processes. In a 28-day challenge test on barley grains, SO at 1% effectively reduced counts of the two Fusarium species to levels equivalent to the negative control, with only partial efficacy against Aspergillus flavus. Mechanistic assays indicated that SO does not act through cell wall disruption or ergosterol binding. A preliminary ex vivo porcine intestinal assay showed no histological signs of mucosal irritation at ten times the highest MIC. Thus, non-refined sunflower oil shows potential as a natural antifungal agent for stored grains under the conditions evaluated, and further studies are needed to confirm its efficacy and safety.
Abstract Saccharomyces cerevisiae serves as a cornerstone microorganism in industrial fermentation, and its production processes frequently involve co-fermentation with companion microbes. Among these, lactic acid bacteria (LAB) are commonly employed in combination with S. cerevisiae for various fermentation applications. Our previous work has demonstrated that co-cultivation with Lactiplantibacillus plantarum confers improved ethanol tolerance on yeast cells. Nevertheless, the precise determinants responsible for this beneficial effect remain incompletely elucidated. In the present study, we performed a sequential factor-exclusion strategy to systematically dissect the specific co-culture-derived elements that contribute to this phenotypic enhancement. Our experimental evidence demonstrated that glucose competition and the secretion of compounds by L. plantarum significantly contributed to the elevated ethanol resistance of yeast, whereas competition for physical space exerted no measurable influence. These observations advance our mechanistic understanding of inter-species dynamics between S. cerevisiae and accompanying microorganisms in fermentation ecosystems.
Abstract This study investigated the in vitro antibacterial efficacy of classical herbo‑mineral formulations, Rasa Manikya (RM) and Rasa Sindura (RS), and also evaluated their ameliorative potential in combating multidrug‑resistant (MDR) Salmonella Typhimurium -induced sepsis in a murine model. Both RM and RS exhibited dose‑dependent antibacterial activity in agar well diffusion and broth microdilution assays. Oral administration of RM and RS to mice at a dose of 25 mg/kg body weight significantly (p < 0.05) improved clinical scores, restored haematological and biochemical parameters, and moderately reduced bacterial burden in liver, spleen, and kidney, compared to the healthy group. RM and RS treatment also rebalanced hepatic oxidant/antioxidant status and ameliorated histopathological damage in vital organs. Principal Component Analysis revealed a clear shift in treated groups toward normal physiological profiles. Analysis of survival trials using the Log-Rank (Mantel-Cox) test identified significant differences, with treated mice groups- RS (87.25%) and RM (81.25%) showing markedly enhanced survival, compared to untreated controls (50%). The ameliorative effects of RM and RS in a murine sepsis model underscore their potential as alternative therapeutics. However, further studies—particularly those addressing potential toxicity, and pharmacokinetics,—are warranted before any consideration of clinical application.
Abstract Sophorose is a strong soluble inducer of cellulase biosynthesis in Trichoderma reesei, but its practical use remains limited by availability and cost. In this study, an integrated strategy was developed to improve cellulase production by combining sophorose biosynthesis, sophorose-based induction, and heterologous β-glucosidase expression. β-glucosidases from T. reesei QM6a, Penicillium digitatum Pdw03, and Aspergillus niger CBS 513.88 were expressed in Escherichia coli BL21(DE3) and compared for sophorose formation. The A. niger-derived enzyme rAnCel1A showed the highest transglycosylation activity, producing 8.42 ± 0.21 g L−1 sophorose at 47°C and showing optimal performance at pH 3.2. In a 20-L bioreactor, an enzymatically synthesized sophorose–glucose mixture containing 12.7 ± 0.8 g L−1 sophorose triggered detectable cellulase production within 24 h after induction, whereas glucose-only feeding failed to initiate cellulase production despite comparable biomass formation. Heterologous expression of fungal cel1A genes in T. reesei Rut-C30 further increased β-glucosidase and filter paper activities. The An-cel1A advantage disappeared after gene-dosage normalization, suggesting higher expression. These results provide a feasible framework for coupling inducer biosynthesis with cellulase production in T. reesei.
Abstract Staphylococcus spp., other than S. aureus (SOSA, formerly CoNS), are opportunistic pathogens often linked to biofilm infections on indwelling devices. Their rising antibiotic resistance highlights the need for novel therapies. Bacteriophages are promising due to their specificity and ability to inhibit cell growth and biofilm formation. In this study, lytic phages isolated from swab pools were characterized against six clinical S. epidermidis and S. warneri isolates. Two distinct groups were identified via their host range, transmission electron microscopy, and genome sequencing. Group 1 phage ΘBRJ9 belongs to genus Sepunavirus (Myoviridae), while Group 2 phage ΘBRJ18 belongs to genus Andhravirus (Podoviridae). Both showed rapid adsorption, short latent periods (20 min), and high burst sizes (79 and 60 PFU/cell). They strongly inhibited planktonic SOSA growth at MOI 10, with efficacy comparable to or better than vancomycin, and their genomes lacked lysogeny, virulence, or resistance genes. These phages display a lytic lifestyle and are candidates for targeted SOSA therapies. Future work will assess biofilm efficacy, antibiotic synergies, and in vivo performance.
