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The current research aims to evaluate the susceptibility of the tomato of the tomato (Solanum lycopersicum) cultivars 65,015 (CV1), Basma (CV2), Dalia (CV3), 320 (CV4), and 844 (CV5) to early blight disease caused by Alternaria solani, A. alternata, and Curvularia lunata under greenhouse conditions. All five cultivars were inoculated with the tested pathogenic fungi. The results showed that CV1 was highly resistant to early blight disease whereas CV5 was most susceptible to it. The causal pathogens decreased the total chlorophyll contents of the tomato cultivars and caused the accumulation of hydrogen peroxide, superoxide anions, and lipid peroxidation, having the greatest effect in CV5 followed by CV4 and the least effect in CV1. The pathogenic fungi also significantly stimulated the synthesis of ascorbic acid and reduced the production of glutathione, salicylic acid, soluble phenolic compounds, phenylalanine ammonialyase, and polyphenol oxidase in all the infected tomato cultivars except CV4 or CV5, with CV1 showing the greatest changes. Histopathological studies of the infection phases of A. solani and C. lunata on the highly resistant cultivar CV1 and the susceptible cultivar CV5 under the light microscope demonstrated that the leaves of CV1 were coated with thick epidermal hairs and glandular hairs and had relatively few stomata, whereas those of CV5 had a limited number of hairs and many stomata. Electron microscopy further showed that the fungal mycelia of A. solani and C. lunata easily attacked the open stomata of the hypersensitive cultivar CV5.

In this study, two highly thermotolerant and methanol-tolerant lipase-producing bacteria were isolated from cooking oil and they exhibited a high number of catalytic lipase activities recording 18.65 ± 0.68 U/mL and 13.14 ± 0.03 U/mL, respectively. Bacterial isolates were identified according to phenotypic and genotypic 16S rRNA characterization as Kocuria flava ASU5 (MT919305) and Bacillus circulans ASU11 (MT919306). Lipases produced from Kocuria flava ASU5 showed the highest methanol tolerance, recording 98.4% relative activity as well as exhibited high thermostability and alkaline stability. Under the optimum conditions obtained from 3D plots of response surface methodology design, the Kocuria flava ASU5 biocatalyst exhibited an 83.08% yield of biodiesel at optimized reaction variables of, 60 ○C, pH value 8 and 1:2 oil/alcohol molar ratios in the reaction mixture. As well as, the obtained results showed the interactions of temperature/methanol were significant effects, whereas this was not noted in the case of temperature/pH and pH/methanol interactions. The obtained amount of biodiesel from cooking oil was 83.08%, which was analyzed by a GC/Ms profile. The produced biodiesel was confirmed by Fourier-transform infrared spectroscopy (FTIR) approaches showing an absorption band at 1743 cm−1, which is recognized for its absorption in the carbonyl group (C=O) which is characteristic of ester absorption. The energy content generated from biodiesel synthesized was estimated as 12,628.5 kJ/mol. Consequently, Kocuria flava MT919305 may provide promising thermostable, methanol-tolerant lipases, which may improve the economic feasibility and biotechnology of enzyme biocatalysis in the synthesis of value-added green chemicals.

Botrytis umbel blight caused by Botrytis allii is a major disease that attacks onion crop. In vitro, Trichoderma viride, Penicillium chrysogenum, and Saccharomyces cerevisiae and extract of bitter apple fruits (Citrullus colocynthis) showed antagonistic effect and inhibited the mycelial growth of B. allii. Gas chromatography–mass spectrometry (GC-MS) analysis of bitter apple fruits showed the existence of 37 compounds and their derivatives. Among them, 10 compounds constituted 58.66% of the total analyses. Greenhouse experiment approved that the extract of bitter apple fruits was the most effective in reducing disease incidence and severity, followed by P. chrysogenum, when they were applied 2 days pre-inoculation with the pathogen. All treatments significantly increased the total phenolic contents than the untreated control, but the highest increase was obtained when S. cerevisiae and P. chrysogenum were applied. A positive correlation was found between the activity of bioagents and improvement of peroxidase and phenylalanine ammonia-lyase enzymes in onion plants to resist infection with the pathogen. P. chrysogenum caused the highest increase in polyphenoloxidase activity in infected onion plants, while S. cerevisiae showed the lowest level of this enzyme. The study approved that application of the bioagents not only protected the onions against Botrytis disease but also enhanced the content of antioxidant compounds in onions. This encourages the application of such preparations to manage the production of onion crop, especially in the organic farming that bans the application of any chemicals.