Six endophytic fungal species belonging to genera, Aspergillus, Alternaria, Penicillium, and Fusarium, as identified morphologically, were isolated from healthy leaves, stems, and roots of the medical plant Euphorbia peplis collected from Damietta governorate of Egypt. One Fungal strain morphologically identified as A. oryzae, was selected as the most potent producer of Kojic acid, that produced in this study by agricultural waste fermentation using sugarcane bagasse, corn cobs, and rice straw. The bagasse agricultural waste fermentation using endophytic Aspergillus oryzae strain was optimized as a source of Kojic acid in a cheap, fast, and environmentally beneficial way at agitation state rather than static and pH 6.0 after 20 days of incubation at 28 °C. Ethyl acetate extract of filtrate of Aspergillus oryzae showed promising antioxidant activity against DPPH free radical, recording IC50 = 5.7. Also, the E A extract was separated using Gas Chromatography technique recording RT: 31.95 min. and MW: 142.The study aims to the fermentation biotechnology used to reduce the cost of industrial KA production through optimization of environmental conditions of the biosynthesized KA with low toxicity and high antioxidant efficiency.

The utilization of nanotechnology and biotechnology for enhancing the synthesis of plant bioactive chemicals is becoming increasingly common. The hairy root culture technique can be used to increase secondary metabolites such as tropane alkaloids. Agrobacterium was used to induce hairy roots from various explants of Hyoscyamus muticus. The effect of nano-silver particles (AgNPs) at concentrations of 0, 25, 50, 100, and 200 mg/L on tropane alkaloids synthesis, particularly hyoscyamine and scopolamine, was studied in transgenic hairy root cultures. Different types of explants obtained from 10-day-old seedlings of H. muticus were inoculated with two strains of Agrobacterium rhizogenes (15,834 and A4). The antimicrobial activity of an ethanolic extract of AgNPs-induced hairy root cultures of H. muticus was tested. The frequency of hairy roots was higher in hypocotyl, root, leaf, and stem explants treated with A. rhizogenes strain A4 compared to those treated with strain 15,834. In transgenic hairy root cultures, AgNPs application at a concentration of 100 mg/L resulted in the highest total tropane alkaloid production, which exhibited broad-spectrum antimicrobial activity. The study demonstrated the potential of nano-silver as an elicitor for promoting the production of target alkaloids in Hyoscyamus muticus hairy root cultures, which exhibit high biological activity.

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INTRODUCTION Filamentous fungi produce a diverse array of secondary metabolitessmall molecules that are not necessary for normal growth or development. Secondary metabolites have a tremendous impact on society; some are exploited for their antibiotic and pharmaceutical activities; others are involved in disease interactions with plants or animals. The presence of various phenolic compounds, polysaccharides, and terpenoids and other compounds, is the reason for their potent biological activities as anticancer, antioxidant, antimicrobial, antiaging, hepatic protective, hypoglycemic, hypocholesterolemic, and much more biological activities are discovered every day. The availability of fungal genome sequences has led to an enhanced effort at identifying biosynthetic genes for these important molecules (Chen et al., 2020).

Microbiology journal is one of the series issued twice by the Egyptian Academic Journal of Biological Sciences, and is devoted to publication of original papers related to the research across the whole spectrum of the subject. These including bacteriology, virology, mycology and parasitology. In addition, the journal promotes research on the impact of living organisms on their environment with emphasis on subjects such a resource, depletion, pollution, biodiversity, ecosystem…..etc www.eajbs.eg.net Provided for non-commercial research and education use. Not for reproduction, distribution or commercial use.