Anthocyanin content in the black scented rice (Chakhao): its impact on human health and plant defense

The major anthocyanin compositions of the two black scented rice cultivars (Chakhao Poireiton and Chakhao Amubi) were studied using HPLC. Four main anthocyanins, i.e., delphinidin 3-galactoside, delphinidin 3-arabinoside, cyanidin 3-galactoside and cyanidin 3-glucoside were identified in Chakhao Poireiton while three main anthocyanins, delphinidin 3-galactoside, delphinidin 3-arabinoside and cyanidin 3-galactoside were identified in Chakhao Amubi. In both the cultivars, delphinidin 3-galactoside is the most predominant anthocyanin. The total monomeric anthocyanin content and total phenolics were measured using a modified pH differential method and modified Folin-Ciocalteu method, respectively. The total anthocyanin content in Chakhao Poireiton was found to be 740 mg/kg and Chakhao Amubi was 692 mg cyanidin 3-glucoside/kg of dried powder sample. And the total phenolic content was 577 and 500 mg/100 g of the dried powder sample as Gallic acid equivalent in Chakhao Poireiton and Chakhao Amubi, respectively. The anthocyanin extract showed strong antioxidant activity by DPPH assay, the highest scavenging activity of Chakhao Poireiton and Chakhao Amubi were 70.28 % and 69.73 %, respectively. From the study it can be suggested that supplementation of the black scented rice in the diet will have a great impact on human health. The rich anthocyanin and phenolic help to protect the plant from rice diseases and pests.