Optimization of Polyphenol Oxidase and Peroxidase Production Using Native Bacillus spp. Isolated From Fully Fermented Tea
الموضوعات : Biotechnological Journal of Environmental Microbiology
1 - عضو هیئت علمی
الکلمات المفتاحية: Bacillus spp., Optimization, Peroxidase, Polyphenol oxidase,
ملخص المقالة :
Tea (Camellia sinensis) is a species of evergreen shrubs or small trees in the flowering plant family Theaceae.
One of the major steps in black tea manufacturing is the fermentation process, in which bacteria may be
incorporated. This study aimed at using the one-factor-at-a-time (OFAT) and Taguchi methods to optimize
the production of polyphenol oxidase (PPO) and peroxidase (POD) by Bacillus spp. isolated from fully fermented
tea. The results showed that sucrose and glucose exhibited the greatest effects on the production of
polyphenol oxidase and peroxidase by the strains Bacillus sp. (TB3) and B. licheniformis (TB14), respectively.
In addition, the results indicated that the best nitrogen sources for the production of PPO by Bacillus
sp. (TB3) and POD by B. licheniformis (TB14) were sodium nitrate and ammonium carbonate, respectively.
Based on the obtained results, the medium components for the production of PPO by Bacillus sp. (TB3) at
a pH of 7 were as follows: 0.5% sucrose, 1.0% peptone, 0.8% yeast extract, 0.2% hydrolyzed casein, 0.02%
potassium dihydrogen phosphate, 0.005% magnesium sulfate heptahydrate, and 0.1% sodium nitrate. Moreover,
the optimal culture medium for the production of POD by B. licheniformis (TB14) at a pH of 7 was
as follows: 0.3% of glucose, 1.0% of peptone, 0.8% of yeast extract, 0.2% of hydrolyzed casein, 0.02% of
potassium dihydrogen phosphate, and 0.005% of magnesium sulfate heptahydrate. Increased production of
PPO and POD enzymes was obtained, about 8- and 6-fold more than in the basal culture media, respectively.
