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Fungi are a diverse group of microorganisms that play many roles in human livelihoods. However, the isolation of potential fungal species is the key factor to their utilization in different sectors, including the enzyme industry. Hence, in this study, we used two different fungal repositories—soil and weed leaves—to isolate filamentous fungi and evaluate their potential to produce the cellulase enzyme. The fungal strains were isolated using dichloran rose bengal agar (DRBA) and potato dextrose agar (PDA). For cellulase enzyme production, a rice straw submerged fermentation process was used. The enzyme production was carried out at the different incubation times of 3, 5, and 7 days of culture in submerged conditions with rice straw. Fungal identification studies by morphological and molecular methods showed that the soil colonies matched with Trichoderma reesei, and the weed leaf colonies matched with Aspergillus awamori. These species were coded as T. reesei UMK04 and A. awamori UMK02, respectively. This is the first report of A. awamori UMK02 isolation in Malaysian agriculture. The results of cellulase production using the two fungi incorporated with rice straw submerged fermentation showed that T. reesei produced a higher amount of cellulase at Day 5 (27.04 U/mg of dry weight) as compared with A. awamori (15.19 U/mg of dry weight), and the concentration was significantly different (p &lt, 0.05). Our results imply that T. reesei can be utilized for cellulase production using rice straw.

Fungi are important decomposers in our ecosystem and are useful in metabolite production, bio-degradation and bio-sorption of different substrates and wastes through their mycelial biomass. Fungal species are known to have different preferences for their growth requirements. Two fungal species Pestalotiopsis and Pseudopestalotiopsis useful in many biotechnological applications were studied. Nutrient and physiological requirements for mycelial biomass production such as carbon and nitrogen, pH, light and temperature were investigated. Both fungal isolates were grown in liquid basal medium supplemented separately with various carbon and nitrogen source and incubated under different light, pH and temperature conditions for 15 days. In general, Pestalotiopsis sp. and Pseudopestalotiopsis sp. showed significant preferences for monosaccharide and disaccharide carbon source as compared to sugar alcohols and polysaccharides, whereas ammonium tartrate was more preferred as a nitrogen source compared to ammonium nitrate, ammonium sulphate and other ammonium salts. These two fungal species were able to grow and produce good mycelial biomass (223.33 mg for Pseudopestalotiopsis and 136.67 mg for Pestalotiopsis) at temperature range of 15°C to 30°C and (290.00 mg for Pseudopestalotiopsis and 256.67 mg for Pestalotiopsis) on media pH of slightly acidic to slightly alkaline. However, they showed no significant preferences between constant light, total darkness and alternate light conditions. The results from this study will be very useful for the mycelial biomass production of Pestalotiopsis sp. and Pseudopestalotiopsis sp. for their biotechnological applications.