Isolation of Penicillium expansum WH-3 for the production of L(+)-tartaric acid / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The L(+)-form of tartaric acid (L(+)-TA) exists extensively in nature, and is widely used in the food, chemical, textile, building, and pharmaceutical industries (Su et al., 2001). The main method for L(+)-TA production is microbial transformation by cis-epoxysuccinate hydrolase (CESH), which can catalyze the asymmetric hydrolysis of cis-epoxysuccinic acid or its salts to TA or tartrate (Bao et al., 2019). Seventeen species containing CESH have been isolated so far. However, most species for L(+)-TA production have been reported from bacteria (Xuan and Feng, 2019). The only fungus isolated from soil by our lab recently, that could be used as catalyst for the process under acidic condition, is Aspergillus niger WH-2 (Bao et al., 2020). In order to find strains with new characteristics, this study attempted to isolate a new CESH source from fungi and investigate its application value.

Identification of digestive hydrolases in the larval midgut of the camel nasal bot fly cephalopina titilla tor clark [diptera: Oestridae]

Activities of digestive hydrolases associated with midgut of the third instar larva of Cephalopina titillator were investigated. Based on the hydrolysis of synthetic substrates and optimum pH, it was found that C. titillator midgut contains trypsin-like [optimum pH, 9], chymotrypsin esterase-like [optimum pH, 8], carboxypeptidase A and B [optimum pH at 8.5 and 7 respectively], alkaline- and acidphosphatase [optimum pH at 9 and 5 respectively] and membrane bound leucine aminopeptidase [optimum pH, 8]. An acid proteinase activity was detected, by the ability to hydrolyze acid denaturated haemoglobin; and it seems to be close to pepsin than cathepsin-like enzyme. It has a maximum activity at pH 3.5. alpha-Glucosidase activity, and was also identified [optimum pH at 6] in the midgut, and seems to be membrane bound