2.4.3.1 Hesperidin
Synonyms Cirantin; Hesperitin 7-rhamnoglucoside; Hesperetin-7-rutinoside.
Biological Source Hesperidin is the most predominant flavonoid in lemons and sweet orange Citrus sinensis (Linn.) Osbeck. It is also found in the rind or peel or unripe, green citrus fruits, for instance: Bitter Orange (Citrus aurantium Linn.); Lemons (Citrus limon Linn); Citron (Citrus medica Linn.).
Geographical Source Citrus fruits are abundantly grown in the tropical African countries e.g.; Togo, Nigeria, Ghana, besides the Mediterranean regoins.
Preparation The glucoside may be isolated by adopting the laid down detailed procedures as in Section 2.4.2.1. It is also present in the dried orange peel upto 8% and it occurs in the highest concentration in the white portion of the peel usually termed as albedo.
Description Hesperidin is a colourless needle like crystals. It seems to be closely related to Vitamin P (Citrin). It is readily soluble in hot water, sparingly soluble in alcohol and cold water, and practically insoluble in ether, benzene and chloroform.
Chemical Structure The Structure of hesperidin is given as under:
The hesperidin chalone, comprising of an embeded phloroglucinol ring is promptly converted to flavones (e.g., hesperidin) in an acidic medium, when heated or allowing it to stand in the dry state for a long duration. However, methylation of the hesperidin chalone helps in the ultimate methylation of one of the phenolic moieties present in the phloroglucinol portion of the chalone not only stablizies the corresponding methyl chalone but also prevents closure of the ring to produce
the flavones [see structure on next page].
Uses
1. It is normally used in conjunction with ascorbic acid to minimise capillary fragility.
2. It is also indicated in the prevention and management of capillary fragility or permeability in hypertension, cardiovascular and cerebrovascular disease, and also in habitual and threatened abortion.
