Background: With increasing energy requirements and limited fuel resources, finding cheap renewable sources is essential. The objective of our current economy was to enhance biodiesel production from the Penicillium commune NRC 2016. Methods: Four mutagenic agents were used to improve the lipid production from P. commune NRC 2016; a physical agent was gamma radiation and the chemical mutagenic agents including ethyl methanesulfonate (EMS), ethidium bromide (EB), and sodium azide (NaN3). Inter-Simple Sequence Repeats molecular (ISSR) marker was used to compare the wild type of P. commune NRC 2016 and the resulting mutants and the result showed a major difference between the wild type and its mutants. Response surface methodology was used to optimize the culture conditions for lipid production by P. commune NRC 2016 and the induced mutants using hydrolysate that was produced from bagasse using B. cereus 3SME. Results: The maximum lipid content (g/l) for P. commune NRC 2016 wild type, gamma mutant, EB mutant, and EMS mutant were 2.01, 2.55, 1.71, and, 2.27, respectively. Gas chromatography analysis for biodiesel compositions produced from P. commune NRC 2016 wild type and its mutants were mainly C16-C18 that suitable to produce biodiesel. The physical properties such as density, viscosity, cloud point, pour point, and cetane number for biodiesels from P. commune NRC 2016 and its mutants were similar to standard biodiesel and could be applied on large scale.

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Amylases are a group of commercially important enzymes with various clinical, medical and biotechnological applications. The current study aims to optimize the agitation and aeration (oxygen transfer) conditions for α-amylase production by Aspergillus flavus using water hyacinth extract; as an available waste and very cheap nutritional substance, in a lab scale stirred tank bioreactor (submerged fermentation). Data showed that the maximal cell biomass and enzyme specific activity were reached at low aeration rate (0.5 v/v/m) and moderate agitation speed (200 rpm). The maximum specific amylase production rate has been reached after 24 hrs. In addition, it has been confirmed that scaling-up Aspergillus flavus does not, inversely, affect α-amylase productivity compared with flask level production. Aspergillus flavus has been approved as promising fungal isolate for production of a-amylase using water hyacinth for application in many fields.

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