Dau Ha Chau (DHC) was produced by selecting and growing native kinds of Baccaurea
ramiflora Lour. in Vietnam, where the fruit is utilized for fresh eating not only due to its
distinctive sour-sweet flavor, but also because of its vitamins and minerals for the body.
With the aim to enhance the value of this fruit, the peel, pulp, and seed extracts were
determined antioxidant, antibacterial and antidiabetic activities. The filtrates from ethanol
extract of peel and seed powders and fruit juice from squeezing pulp were evaporated at
58°C to create the extracts. The six methods of TAC, DPPH, ABTS•+, RP, FRAP, and NO•
(antioxidant activities), four bacterial strains and two enzymes (associated with type 2
diabetes mellitus) were evaluated. The results showed that the extract of DHC peel
exhibited the highest antioxidant activity (EC50 value from the six methods), antibacterial
activity (MIC value), enzyme inhibiting activity (IC50 value), total phenolics content and
total flavonoids content, at 643.81 µg/mL, 787.42 µg/mL, 651.10 µg/mL, 718.22 µg/mL,
270.38 µg/mL, 662.44 µg/mL, 16 < MIC ≤ 32 mg/mL (against Propionibacterium acnes,
Escherichia coli and Bacillus cereus), 32 < MIC ≤ 64 mg/mL (against Staphylococcus
aureus), 2780.91 µg/mL (against α-amylase), 541.24 µg/mL (against α-glucosidase),
119.43 mg GAE/g and 207.17 mg QE/g, respectively, whereas the opposite was true for
extract of DHC seed. DHC pulp extract came second in all analytical methods. Pearson
correlation coefficients with r value (0.63-0.99) showed a reasonably strong relationship
between total phenolics and flavonoids contents, and antioxidant and enzyme inhibiting
activities. This is the first report on the antioxidant, antibacterial and antidiabetic activities
of DHC Ha Chau fruit extracts, which could be developed for medicinal, pharmaceutical,
food preservative purposes, or industrial foods in the future.