Dr Vikas Sharma & Dr Akash Sharma Fruit species are largely appreciated and highly consumed all over the world. There are several biological reasons regarding consumption of fruits to reduce/prevent chronic diseases. Fruits provide a rich source of nutrients, energy, vitamins, minerals, fiber and numerous other classes of biological active compounds. Epidemiologic studies strongly suggest that high intake of fruits considerably leads to reduced risk of various chronic diseases. In addition, some wild fruit species are not taken by people, but still they possess many pharmaceutical and medicinal properties. Citrus fruits and lemonoids are known to prevent heart diseases, inflammation and arterosclerosis along with hepato-protective, antimicrobial, neuro-protective, antioxidants, anti-diabetic, anticancer properties. Several bioactive compounds are reported in berry fruits with antioxidant, anti-inflammatory, cardio-protective and neuro-protective effects. The fruit extract of pomegranate is also been reported to have medicinal properties against several types of cancer. Phenolic acid: Phenols are secondary plant metabolites with nutritive quality in terms of aroma, taste, flavor and colour. Several berries, apples, pears and grapes contain upto 200-300 mg polyphenols per 100 g fresh weight. Among berries, blueberries, raspberries and blackberries are rich in hydroxybenzoic and hydroxycinnamic acids. Some of the derivatives of hydroxybenzoic acids are used as additives to reduce the oxidation of nutrients and to enhance the nutritional value in foods. Seeds of grape are rich in phenolic compounds – gallic acid, catechins and epicatechin with variety of procyanidins. In particular, peels are an abundant source of natural flavonoids. The phenolic content in peel of lemons, oranges and grapefruit is about 15 per cent more than the edible portion. Anthocyanins are abundant in berries and grapes with multifaceted medicinal and biological values. Flavonoids are one of the largest groups of phenolic compounds that play a significant role in various biological activities including antioxidant, antimicrobial, antimutagenic and cytotoxic activities. In fruits, they are found in the form of glycosides or acylglycosides whereas acylated, methylated and sulphate molecules are less frequent and are in lower concentration. Myricetin is another plant flavonol that is abundant in fruits like berries and grapes and is an effective therapeutic specifically against diabetes mellitus. Myceritin induced apoptosis and enhanced cytotoxicity in ovarian cancer cell lines. Naringenin (a citrus flavanone), is proved as a potent candidate for dengue treatment by impairing dengue virus replication in human monocytes. In clinical trial experiments, therapeutic role of anthocyanin compounds was observed in both in vitro and in vivo studies and their possible benefits against chronic diseases. It is revealed from a study conducted on blueberries that anthocynanins are readily metabolized to various phenolic derivatives thus contributing to human health. There is a great correlation between anthocyanins intake and cardiovascular health reiterating the significance of these flavonoids. Carotenoids: Carotenoids are C40 tetraterpenoids formed from eight C5 isoprenoid units joined head to tail, resulting in a symmetrical structure. They are comprised of naturally occuring yellow, orange or red compounds with their structural diversity, wide distribution and multiple functions. In fruits and vegetables, around 800 carotenoids have been identified. Among carotenoids, the carotenes (?-carotene, lycopene) are the unsaturated hydrocarbon whereas the xanthophylls (?-cryptoxanthin, canthaxanthin, violaxanthin) are oxygenative derivatives containing hydroxyl, keto, epoxy and aldehyde substituents. In fruits, xanthophylls are present in abundance. In fruits like mango and papaya, carotenoids are present in oil droplet in an esterified form with fatty acids. Lutein is the main carotenoid and decrease in the level of carotenes and lutein at the onset of fruit coloration with an increased level of xanthophylls was noticed. Tocopherols: These are lipid soluble bioactive compounds present in fruits and vegetables, formed by a 6-chromanol ring structure methylated to varying degrees at C5, C7 and C8 positions and a saturated C16 side chain at C2 position. Tocopherol is the term used for vitamin-E and tocotrienols, consist of four tocopherols like ?, ?, ? and ?. They act as source of antioxidants and also provide beneficial effect in the inhibition of tumor development, provide protection to membrane fatty acids from attack of free radical. Previous study demonstrated that grape seed oil provide a good source of linolenic acid with vitamin A and rich in ?, ? and ? tocopherols, ? and ? tocotrienols, with ? tocotrienol being most important quantitatively Stilbenes: Grape berries are abundant in stilbenes i.e., resveratol present in fruits, leaves, stems, roots, canes and possess various biological activities like antioxidant, antibacterial, antifungal, cardio-protective, neuro-protective, anti-aging and anti-cancer. About 13 grapevine stilbenes are quantified with e- viniferin and resveratol being more abundant.
