No abstract

Aims: Observation of the dependence of a-L-rhamnosidase activity on pH and temperature and the capability to hydrolyse concentrated naringin solutions and hesperidin suspensions of enzyme complexes produced by several fungi. Methods and Results: The enzymes were produced by several wild strains of mesophilic fungi grown in liquid media containing rhamnose as sole carbon source. The properties and their ranges of values measured were as follows: (i) optimum pH, 3AE5-6AE5; (ii) optimum temperature, 50-65°C; (iii) hydrolysis of supersaturated 100 g l )1 naringin solutions, 45-100% and (iv) hydrolysis of hesperidin suspensions, 6-35%. Conclusions: Some a-L-rhamnosidase enzymes hydrolysed supersaturated naringin solutions with a high yield. The enzyme produced by Fusarium sambucinum 310 showed good activity even at pH 10. Significance and Impact of the Study: Crude enzymes with possible utilization as catalysts for the manufacture of hydrolysis products of the flavonoid glycosides were found.

Penicillium ulaiense exhibited carboxymethylcellulase, pectinase, protease, amylase and phenolase activities, while no xylanase, cellulase, lipase or ligninase activities were found. Pectinolytic action was studied in liquid medium, showing low levels of pectinesterase and pectinase production. No mycotoxins were detected by thin-layer-chromatography.

No abstract