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Bacillus thuringiensis (Bt) represents one of the most economical biopesticides to date. It produces toxins with insecticidal activity against many agricultural pests, including members of the genus Spodoptera. However, Bt tolerance leads to inefficiency in biological control. To overcome this problem, discovering the hidden cause(s) for the evolution of insect tolerance against Bt is of great importance. We hypothesized that changes in the gut microbiota due to the frequent application of Bt is one of those hidden causes. To investigate this hypothesis, we studied the effect of Bt Cry1c application on the Spodoptera littoralis larval gut microbiota in both Bt-susceptible and Bt-tolerant populations. The results revealed changes in the diversity and abundance of gut bacterial composition between the susceptible and tolerant populations. A high abundance of Enterococcaceae was detected in the tolerant population. Interestingly, Cry1c tolerance eliminates the bacterial genera Klebsiella and Serratia from the larval midgut. These changes may confirm the mechanism developed by Spodoptera larvae to counteract Bt Cry1c toxicity. Understanding the B. thuringiensis–gut microbiota interaction may help in improving biocontrol strategies against agricultural pests to overcome the evolution of tolerance.

Humic acid (HA) is natural product obtained by plant decomposition. It improves systematic resistance in plants and the shelf life of food products. Oyster mushrooms occupy important place in human food due to their palatability and nutritional enrichment. Little is known about the impacts of HA on mushrooms yield. Therefore, a trial was conducted to study the role of HA improving growth, nutritional and chemical composition of two oyster mushroom strains (Pleurotus ostreatus, Lentinus sajor-caju). Pure cotton waste amalgamated with five levels of HA, i.e., 2, 4, 6, 8 and 10 mM/L was used as growth media. The responses of oyster mushroom to HA were recorded in various traits i.e. time to spawn initiation, time to mycelium growth initiation, time to maturity of flushes, time to initiation of pinheads, yield, biological efficiency (BE), minerals (N, P, K, and ascorbic acid, Zn, Cu, Mg, Mn, Fe, Na and Ca), sugars (total sugars, reducing and non-reducing sugars), proximate, total soluble solids (TSS), acidity, and Fourier-transform infrared spectroscopy (FTIR). The HA amalgation notably improved the growth, nutritional and chemical composition of oyster mushroom; however, strains differences were non-significant (>0.05) to various level of HA on dry weight basis TSS ranged from 6 to 6.8 °Brix, total sugar was 5.8–11.9%, reducing sugar was 2.6–3%, non-reducing sugar was 9.2–9.6%, ascorbic acid was 35.9–43 mg/100 g, carbohydrates were 68–74%, crude protein was 62–69%, crude fiber was 22–37%, fat contents were 2.5–17%, ash content was 9–11%. These results suggest that HA is an innovative substrate for valuable and high-quality production of the oyster mushroom.

Cellulases hydrolyze cellulosic material and the production is highly expensive than other commercial enzymes. Hence, there is a continuous search for cheap and novel substrates to minimize the production of this enzyme. In our study, a fungal isolate, Trichoderma hamatum NGL1 was isolated to produce endoglucanase (EGase) using cow dung in solid state fermentation (SSF). The process parameters were initially screened by a traditional one variable-at-a-time approach method, followed by a two level full factorial design. A two level full factorial design showed that pH, moisture (physical factors) and oat meal (nitrogen source) were the significant process parameters to improve the enzyme production (p

Tamarix aphylla is a Saudi herb, which possesses antimicrobial properties and potentially introduces a solution to the subsequent dilemma caused by agrochemicals and antifungal misuse. The current study aimed to assess the fungicidal properties of water and ethanolic extracts of T. aphylla leaves against Macrophomina phaseolina, Curvularia spicifera, and Fusarium spp. The chemical composition of T. aphylla was evaluated by gas chromatography/mass spectrometry technique (GC–MS) and Fourier-transform infrared spectroscopy (FTIR). The antifungal assay assessed the fungal growth inhibition using the poisoned food technique. Scanning and transmission electron microscopy (SEM and TEM) were used to evaluate the structural changes induced in the fungal species post-treatment by T. aphylla. FTIR and GC–MS analysis revealed that T. aphylla extracts were rich in aromatic and volatile compounds, such as Benzeneselenol, Gibberellic acid, and Triaziquone, which proved multiple antifungal properties. The results showed significant inhibition in the growth of all species (p < 0.05) except for F. moniliforme, where the water extract induced the highest mycelial growth inhibition at the dose of 30%. The highest inhibition was for M. phaseolina treated with the water extract (36.25 ± 1.06 mm, p < 0.001) and C. spicifera, treated with the ethanolic extract (27.25 ± 1.77 mm, p < 0.05), as compared to the untreated control and the positive control of Ridomol. SEM and TEM revealed some ultrastructural changes within the fungal growth of treated M. phaseolina, which included the thickening and mild rupture of mycelia. Those findings suggested the robust antifungal properties of T. aphylla against some filamentous fungi. The phenolic composition illustrated the potential fungicidal properties of T. aphylla. Additional studies are required to focus on more antimicrobial properties of T. aphylla against other species, particularly those that might benefit the medical field.

Abstract Background Vulvovaginal candidiasis (VVC) represents a universal health hazard that contributes to significant morbidity in women. Resistance of Candida to antifungal therapy has been reported as a public health problem. So, the objective of our current study is to detect resistance profile of different candidal strains. Methods In this study, isolated Candida strains were identified by conventional methods, confirmed by internal transcribed spacer (ITS) sequencing, and phylogenetically analyzed with reference strains in GenBank. Also, sensitivity of different Candida strains to common antifungal agents was evaluated by disc diffusion method. Results Candida albicans was identified as the most frequent strain (63%) followed by non-albicans strains, such as C. glabrata (20%), C. tropicalis (13%), and C. krusei (4%). Sensitivity of Candida strains (C. albicans, C. tropicalis and C. glabrata) to commonly used antifungal agents was evaluated through the disc diffusion method. C. glabrata was the most resistant strain and considered to be a multidrug-resistant pathogen, while both, C. albicans and C. tropicalis showed high susceptibility to terbinafine. In contrast, C. albicans showed resistance to fluconazole, clotrimazole, and nystatin, while C. tropicalis, considered as the most sensitive strain, was susceptible to all the antifungal agents tested except nystatin. Terbinafine was the most effective antifungal agent against both C. tropicalis and C. albicans, and hence its minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) for C. albicans and C. tropicalis were evaluated. MICs of terbinafine against C. albicans and C. tropicalis were 5 μg/ml and 2.5 μg/ml, while their MFCs were 10 μg/ml and 5 μg/ml, respectively. Conclusion The emergence of resistant Candida strains necessitates conduction of the antifungal susceptibility test prior to deciding the medication regime.