Biotechnological Production of Kojic Acid Synthesized by Endophytic Fungi, Aspergillus oryzae Isolated from Euphorbia peplis.

Abstract

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.

Optimization of Culture Conditions for Kojic Acid Production in Surface Fermentation by Aspergillus Oryzae Isolated From Wheat Grains

“…The culture was incubated at different temperatures (5, 20, 28, 37, and 45°C) to determine the optimum incubation temperature. The incubation period was optimized by incubating the culture at different periods (5,6,7,8,9,10,11,12,13,20). Effect of different amino acids (arginine, histidine, methionine, lysine and alanine) at 0.2 g/l was determined.…”

“…Some enzymes like glucose dehydrogenase, glucosen -6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glucose oxidase and gluconate dehydrogenase have been detected in mycelial extracts of different isolates of Aspergillus flavus that gives kojic acid in large amounts. Also, kojic acid was detected with pentoses, glycerol, starch and dihydroxyacetone as substrates 5 .…”

“…Kojic acid is a secondary metabolite formed during aerobic fermentation of carbohydrates by several species of fungi as well as some bacterial strains of the two bacterial genera Acetobacter and Brevibacterium [2][3][4] . Aspergillus and Penicillium species are widely known among fungi as the best kojic acid producers 5 . Amongst the species of Aspergillus, A. flavus 6 , A. oryzae 7 , A. tamarii 8 and A. parasiticus 9 were regarded as the main kojic acid source in large amounts.…”