Comparative Study of Vitamin C Contents in Fruits and Medicinal Plants

Vitamin C or ascorbic acid, a very useful constituent for the redox mechanism, is used in medicine and food to prevent oxidation. A UV-spectrophotometric method was developed for the determination of vitamin C in 30 different fruits and medicinal plants collected from the local market at Peshawar and Botanic Centre, PCSIR Labs Peshawar. Among the fruit samples, the highest amount of vitamin C was found in Psidium guajava, while in others the concentration was between 26 and 29 mg/ 100 g. In case of the medicinal plants, the highest amount of ascorbic acid was found in Citrullus colocynthis 161.42 mg/ 100g, while least amount was found in Foeniculum vulgare 28.54 mg/ 100g. The presence of high amount of vitamin C in medicinal plants than in fruits and their juices is due to its higher stability in these media, as Vitamin C is usually highly sensitive to heat, light, pH, time, oxygen, temperature and in aqueous solution etc. The main purpose of the study was to determine the amount of vitamin C in different fruits, their juices and medicinal plants that could be used as a source of vitamin C.