The extraction source is the mature skin of Vitisvinifera L., a grape plant in the family Vitaceae.

【 Plant morphology 】 Deciduous woody vine, up to 10 meters long. The young stem is bald or slightly hairy. Leaves are papery, alternate, round or oval in shape, 10-20cm wide, often 3-5 lobed, heart-shaped at the base, with coarse and slightly sharp teeth at the edges, and often densely covered with spider silk like hairs below; The petiole is 4-8cm long. The flowers are heterozygous, heteromorphic, and the inflorescence is large and long, opposite to the leaves in the chemical book; Inflorescence stalk without tendrils; Calyx extremely small, cup-shaped, with a full or indistinct 5-toothed cleft; Petals 5, yellow green in color, with the tip glued together but not unfolded, the base separated, and the whole piece falls off in a cap like shape when flowering; Stamen 5; The flower disk is raised and composed of 5 glands, with the base fused with the ovary; Ovary with 2 chambers, each chamber containing 2 ovules, style short, conical. Berries are oval to oval in shape, rich in juice, purple black or red with a bluish tint when ripe, and coated with wax powder. The flowering period is in June. The fruiting period is from September to October.