Abstract
Spectrophotometric assays of marula fruit polyphenol oxidase showed a pronounced lag phase due to the presence of endogenous antioxidants. ne total antioxidant capacity (TAC) was quantified in terms of the equivalent concentration of L-ascorbic acid (L-ASC. eq). Freeze-dried marula fruit juice had 2960 mg L-ASC.eq. per 100 g (pH 4.5) or 1872 mg L-ASC.eq per 100 g of sample (PH 7 0) assayed with ABTS. The values compare with the known L-A SC content of 2017 mg per 100 g. The vitamin C content of marula fruit accounts for about 70 % of the TAC. The TAC estimate for marula fruit was 20-40 times greater than levels reported in most other fruits.
| Original language | English |
|---|---|
| Pages (from-to) | 67-82 |
| Journal | Journal of Food Biochemistry |
| Volume | 27 |
| Issue number | 1 |
| Publication status | Published (in print/issue) - Mar 2003 |
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Keywords
- ASCORBIC-ACID
- PLANT FOODS
- CAPACITY
- AFRICA