The Potential Use of a Food-Dyeing Plant Peristrophe bivalvis (L.) Merr. in Northern Vietnam

Abstract

An investigation on the current usage status and experience in using Peristrophe bivalvis (L.) Merr. was conducted in the mountainous region of Northern Vietnam. Five varieties were collected and recorded as a source of foodstuff-dyeing and medicinal plants on indigenous knowledge of ethnic minorities in the study area, of which, three varieties were dyed purple, one red and one yellow-orange; with two varieties being used for the treatment of haemoptysis, dysentery, liver disease, kidney failure, and jaundice. Two extraction methods using organic solvents and aqueous solvent were applied to spectrophotometrically investigate the phytochemical contents of Peristrophe bivalvis varieties. Accordingly, the coloration components of Peristrophe bivalvis varieties were contributed by a complex compound of photosynthetic pigments, anthocyanins, flavonoids. Also, the total phenolics, total flavonoids and effect of extraction methods, dissolved solutions (water and methanol) on these contents were assessed. Besides, screening antioxidant capacity of Peristrophe bivalvis varieties was assayed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) method which showed stronger radical inhibition of organic extractions than that of aqueous extractions. The results of determination of phytochemicals and antioxidant capacity support the knowledge and experience in using Peristrophe bivalvis varieties as natural dyeing production for food and pharmaceutical industry.