Optimization of fermentation conditions of pectin production from Aspergillus terreus and its partial characterization

•Fermentation conditions were optimized for a high yield of pectin productioon by RSM.•Persimmon peel pectin was a highly methoxylated pectin.•Persimmon peel was a promisng source for pectin production. Figures of persimmons for the world's top ten persimmon producing countries are about 4000,000 tons in 2011 and are increasing every year according to FAO statistics. However, there is not any report on pectin production by microbial with persimmon peel as the source. Optimization of fermentation conditions of pectin production from Aspergillus terreus in submerged culture and partial characterization of pectin were carried out in the work. An optimum fermentation condition for pectin production was obtained through a central composite rotatable design in response surface methodology as follows: fermentation time, 30.09h, temperature, 25.00°C and the initial pH in the fermentation medium, 6.90, respectively and the pectin yield reached the maximal value 0.449g/g. Persimmon peel pectin had highly methoxylated (62.51%), high galacturonic acid content (82.28%) than citrus pectin, and was classified as the highly methoxylated pectin, the results indicated that persimmon peel had potential good resources for pectin production. The investigation can make it available to utilize persimmon peel to produce high methoxyl pectin for food industry, pharmacy and cosmetic manufacture.