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An optimization strategy, based on statistical experimental design, is employed to enhance the production of thermostableamylase by a thermotolerant B. licheniformis AI20 isolate. Using one variant at time (OVAT) method, starch, yeast extract, and CaCl 2 were observed to in�uence the enzyme production signi�cantly. erea�er, the response surface methodology (RSM) was adopted to acquire the best process conditions among the selected variables, where a three-level Box-Behnken design was employed to create a polynomial quadratic model correlating the relationship between the three variables and -amylase activity. e optimal combination of the major constituents of media for -amylase production was 1.0% starch, 0.75% yeast extract, and 0.02% CaCl 2 . e predicted optimum -amylase activity was 384 U/mL/min, which is two folds more than the basal medium conditions. e produced -amylase was puri�ed through various chromatographic techniques. e estimated enzyme molecular mass was 55 kDa and the -amylase had an optimal temperature and pH of 60-80 ∘ C and 6-7.5, respectively. Values of max and m for the puri�ed enzyme were 454 mU/mg and 0.709 mg/mL. e -amylase enzyme showed great stability against different solvents. Additionally, the enzyme activity was slightly inhibited by detergents, sodium dodecyl sulphate (SDS), or chelating agents such as EDTA and EGTA. On the other hand, great enzyme stability against different divalent metal ions was observed at 0.1 mM concentration, but 10 mM of Cu 2+ or Zn 2+ reduced the enzyme activity by 25 and 55%, respectively.

Enzymes have played a crucial role in mankind’s challenges to use different types of biological systems for a diversity of applications. They are proteins that break down and convert complicated compounds to produce simple products. Fungal enzymes are compatible, efficient, and proper products for many uses in medicinal requests, industrial processing, bioremediation purposes, and agricultural applications. Fungal enzymes have appropriate stability to give manufactured products suitable shelf life, affordable cost, and approved demands. Fungal enzymes have been used from ancient times to today in many industries, including baking, brewing, cheese making, antibiotics production, and commodities manufacturing, such as linen and leather. Furthermore, they also are used in other fields such as paper production, detergent, the textile industry, and in drinks and food technology in products manufacturing ranging from tea and coffee to fruit juice and wine. Recently, fungi have been used for the production of more than 50% of the needed enzymes. Fungi can produce different types of enzymes extracellularly, which gives a great chance for producing in large amounts with low cost and easy viability in purified forms using simple purification methods. In the present review, a comprehensive trial has been advanced to elaborate on the different types and structures of fungal enzymes as well as the current status of the uses of fungal enzymes in various applications.

Bacterial cellulose (BC), a promising polysaccharide of microbial origin, is usually produced through synthetic (chemically defined) or natural media comprising of various environmental wastes (with exact composition unknown), through low-cost and readily available means. Various agricultural, industrial, and food processing wastes have been explored for sustainable BC production. Both conventional (using one variable at a time) and statistical approaches have been used for BC optimization, either during the static fermentation to obtain BC membranes (pellicle) or agitated fermentation that yields suspended fibers (pellets). Multiple studies have addressed BC production, however, the strategies applied in utilizing various wastes for BC production have not been fully covered. The present study reviews the nutritional requirements for maximal BC production including different optimization strategies for the cultivation conditions. Furthermore, commonly-used applications of BC, in various fields, including recent developments, and our current understanding have also been summarized.

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