Authors: Rahul Dev1 and Malvika Vyas2
1Scientist: ICAR- Central Arid Zone Research Institute, Regional Research Station, Kukma, Bhuj (Gujarat). E-mail: rahul2iari@gmail.com
2 Scholar: Teerthanker Mahaveer University, Moradabad (U.P.)
Bioactive Compounds
Bioactive compounds are secondary metabolites and extra- nutritional constituents that typically occur in small quantities in almost all fruits and having pharmacological or toxicological effects in man and animals. Nutrients like carbohydrates, amino acids, proteins lipids etc in plants are generally not considered as bioactive compound. The typical bioactive compounds in plants are randomly synthesised through plant secondary metabolism. These compounds are produced within the plants in addition to the primary metabolism of compounds (nutrients) required for plant growth and development (Veberič, 2010). Bioactive compounds are being intensively studied to evaluate their effects on health. Many new bioactive compounds have been discovered. These compound, vary widely in chemical structure as well as function and are grouped accordingly. Phenolic compounds, including their sub-category, flavonoids, are present in most of the plants responsible for distinct functions linked to plants protection against biotic and abiotic environmental stress whereas, flavonoids can protect plants against free radicals generated during photosynthesis. Terpenoids attract insect pollinators or inhibit neighbour competing plants. Other secondary metabolites mainly responsible for cellular signalling or other related functions in the plants (Bernhoft, 2010).
Main groups of bioactive compounds in plants
| Sl.No. | Class | Compounds | Sources |
| | Nitrogen Containing Compounds | ||
| Alkaloids | Caffeine, theobromine | Caffea arabica,Theobroma cacao | |
| | Terpenoids | ||
| Monoterpenes | Menthol, limonene | Oil of Citrus | |
| Diterpenes | Gibberellin | Plant hormones synthesized by majority of plants | |
| Triterpenes | Lupeol, ursolic acid | Olea europaea, Fragaria ananassa, | |
| Tetraterpenoids | Carotenes, xanthophylls | Orange and yellow fruits | |
| | Phenolics | ||
| Phenolic acids | Caffeic, chlorogenic Gallic acid (Grape) | All fruit plants including grape | |
| Flavonoids | Anthocyanin, catechin | All fruit plants including grape | |
| Tannins | Gallotannin, condensed | Unripe fruits like persimon, grape | |
| Lignin | Lignin | All vascular plants | |
Source: Veberic, 2010.
Grape (Vitis Vinifera L.) is one of the richest sources of biologically active compounds, like high levels of flavonoids, polyphenols, anthocyanins and stilbene derivatives resveratrol are found in grape (Xia et al. 2010). However, among all bioactive compounds, polyphenols including flavonoids, stilbenes and proanthocyanidins are the most important class of biologically active compounds found in grapes. Polyphenolic substances in grape and its products are usually divided into two groups: flavonoids (kaempferol, quercetin, myricetin and anthocyanins) and non-flavonoids (caffeic, gallic acid and p-coumaric acid). Another class of non-flavonoids are stilbene and stilbene glycosides, with trans-resveratrol as its most well-known representative. Flavonoids are the main groups of soluble phenolics in grapes as well as major contributors of the biological activities in products are primarily located in the outer epidermal cells (the grape skin) (Vasil et al. 2014), whereas about 60%–70% of total polyphenols are stored in grape seeds (Ali et al. 2010). Scientific studies have shown that bioactive compounds of grape extracts have biological and therapeutic effects such as anti-oxidative, anti-carcinogenic, anti-microbial, anti-viral, anti-aging, anti-inflammatory and anti-diabetic activities as well as having cardioprotective, hepatoprotective and neuroprotective effects (Zhao et al. 2011, Vasil et al. 2014). Grape phenolics, including flavonoids and related polyphenols from grape (berry and seeds) have generated remarkable interest based on positive reports of their antioxidant properties and ability to serve as free radical scavengers. The antioxidant activity of grape seed polyphenols is superior to other well-known antioxidants, such as vitamin C (20 times), vitamin E (50 times) and ß-carotene. Procyanidin B4, catechin, and gallic acid at low concentrations (10 µmol/1, 25 µmol/1) were reported to be good cellular preventive agents against DNA oxidative damage. The use of grape antioxidants are promising against a broad range of cancer cells by targeting epidermal growth factor receptor (EGFR) and its downstream pathways, inhibiting over-expression of COX-2 and prostaglandin E2 receptors, or modifying estrogen receptor pathways, resulting in cell cycle arrest and apoptosis (Zhou and Raffoul, 2012).
Health promoting properties of grape biocompounds
Now a days because of grape seed as a safe, novel, highly potent and bio-available free radical scavenger and antioxidant, interest of researchers have focused mainly on this aspect of grape. Grape biocompounds have high nutraceutical values and are commercialized in various forms of different powders, granulates, concentrated or dried extracts etc. Bioactive compounds can reduce the risk of many diseases, including chronic diseases such as cardiovascular disease.
| Sl. No. | Bio-Compounds | Example Compounds | Health Promoting Properties |
| 1. | Stilbenes | · Resveratrol · Piceatannol · Pterostilbene | Anti-Aging and Longevity, breast cancer and variety of age-related vascular disorders (stroke, Parkinson, Alzheimer etc.) |
| 2. | Flavanols |
| Anti-cancer, antioxidant, anti-inflammatory |
| 3. | Flavonoids: |
| antioxidant and anti-inflammatory, anticancer, free-radical, coronary heart disease prevention and anti-human immunodeficiency virus |
| 4. | Phenolic Acids | · Caffeic acid · Coumaric acid · Ferulic acid
| cancers, cardiovascular diseases, diabetes, osteoporosis and neurodegenerative disease |
| 5. | Carotenoids | · Beta-carotene
| Antioxidant, cardiovascular health, Anti-Tumor, Skin and eye health |
References
Aksel Bernhoft. (2010). A brief review on bioactive compounds in plants In: Bioactive compounds in plants – benefits and risks for man and animals (ed.) Aksel Bernhoft Oslo: The Norwegian Academy of Science and Letters pp.11-17.
Ali, K., Maltese, F., Choi, Y., Verpoorte, R. (2010). Metabolic constituents of grapevine and grape-derived products. Phytochem. Rev. 9, 357–378.
Zhou, K. and Raffoul, J.J. (2012). Potential Anticancer Properties of Grape Antioxidants.
Vasil G., Anthony A. and Violeta T. (2014). Recent Advances and Uses of Grape Flavonoids as Nutraceuticals. Nutrients. 6: 391-415; doi:10.3390/nu6010391
Veberič, R. (2010). Bioactive compounds in fruit plants - El. knjiga. - Ljubljana : Biotehniška fakulteta.
Xia, E.-Q., Deng, G.-F., Guo, Y.-J., Li, H.-B. (2010). Biological activities of polyphenols from grapes. Int. J. Mol. Sci., 11, 622–646.
Zhao, J., Khan, I.A., Fronczek, F.R. (2011). Gallic acid. Acta Crystallogr. Sect. E 67, 316–317.
About Author / Additional Info:
Scientist: ICAR- Central Arid Zone Research Institute, Regional Research Station, Kukma, Bhuj