In the growth of the Rubus coreanus Miquel fruits, the unripened (10 days) and ripened (25 days) fruits after flowering were harvested. The chemical characteristics of different maturational stages of the unripened and ripened fruits were investigated. Total amount of phenolic compounds was 4.00-7.56% in the unripened fruits and 3.78-5.57% in the ripened fruits, respectively. Furthermore, total amounts of organic acids such as malic, citric, succinic, and oxalic acids were 16.40 mg/ 100 g in the unripened fruits and 28.82 mg/100 g in the ripened fruits, respectively. In organic acids of the unripened and the ripened fruits, citric acid (8.76-15.47 mg/100 g) was the highest amount among other organic acids. Soluble sugars were significantly increased from 11.07 to 21.54% in the unripened and ripened fruits. Therefore, ripened fruits had the high levels of phenolic compounds, organic acids and soluble sugars. For the biological studies of R. coreanus, methanol extracts of R. coreanus leaves, fruits, and stems were evaluated for their insecticidal activities against Myzus persicae (Hemiptera: Aphididae), Plutella xylostella (Lepioptera: Plutellidae) and Spodoptera litura (Lepioptera: Noctuidae) by leaf dipping method. From these results, the extract of R. coreanus leaves revealed potent insecticidal activity against P. xylostella. However, the methanol extracts of R. coreanus fruits and stems had no any insecticidal activity against M. persicae, P. xylostella and S. litura. The R. coreanus leaves have promising potential as new insecticidal agent against P. xylostella.
This study was performed to determined the antioxidant activities, anticancer and immuno-activities of anthocyanin fraction from Rubus coreanus Miquel fruits (Bokbunja). Anthocyanin fraction extracted from Bokbunja revealed the presence of three anthocyanin components, which were tentatively identified as cyanidin 3-O-sambubioside, cyanidin 3-O-xylosylrutinoside and cyanidin 3-O-rutinoside using RP-HPLC/DAD/MS. The anthocyanin fraction from Bokbunja always showed reducing power and high scavenging activities against DPPH, hydroxy radical (OH) and superoxide anion radical (O2-) similar to general synthetic antioxidant and polyphenol compounds from plant origin. Anthocyanin fraction from Bokbunja showed high inhibition on proliferation of LNCaP and A549 cells and did not inhibit the proliferation of other cancer cells. Immuno-activities of Anthocyanin fraction from Bokbunja were investigated, it showed high promotion of human B and T cells growth about 50% and secretion of IL-6 and TNF-α by treatment after 6 days. Over all, the result of the study suggest that anthocyanin fraction from Bokbunja displays antioxidant activity comparable to that general synthetic antioxidant, also, anthocyanin fraction from Bokbunja are expected to be good candidate for development into source of anticaner and immuno-activator agent in food industry.