Non-flavonoid phenolic compounds

These non-flavonoid phenolic compounds are easily oxidized (89JC428, 89JAFC1069) and show anticancer activities (04MI3707). 

Moreover, apart from these main components, grapes contain secondary metabolites such as flavonoid and non-flavonoid phenolic compounds, sesquiterpenes, and melatonin. Most of the grape s medicinal value can be attributed to its seed and skin, which researchers have found to be rich in nutritional value due to the presence of polyphenolic antioxidants. At least 500 different types of antioxidants have been found in various parts of this fruit [4]. 

Grape phenolics compounds are important to wine colour, flavour, astringency and bitterness, with red wines generally containing 1200-1800 mg gallic acid equiv-alents/L of total phenolics, six- to ninefold more than present in white wines (Kennedy et al. 2006). Hydroxycinnamic acids (non-flavonoid phenolics) are major phenolic compounds of white wines and are responsible for their colour. Other non-flavonoid phenolics contribute flavour, such as vanillin, vinyl phenols and gallic acid. Vinyl and ethyl phenols, which can be present to variable extents, elicit phenolics, medical, Bandaid , barnyard and spicy characters in wine, which are generally... 

The non-flavonoid phenolic constituents in wine are divided into hydroxybenzoic acids and hydroxycinnamic acids, volatile phenols, stilbenes and miscellaneous compounds (e.g. lignans and coumarins). Although non-colored, the non-flavonoid constituents are known to enhance and stabilize the color of red wines by intra- and intermolecular reactions. They furthermore contribute to wine flavor (volatile phenolic acids) and some of them (e.g. resveratrol) exhibit potent biological activities. 

Parejo et al. (2004) identified caffeoyl-quinic acids, dicaffeoylquinic acids, flavonoids and rosmarinic acid among ten main antioxidant phenolic compounds from bitter fennel, F. vulgare, using a simple high-performance liquid chromatography (HPLC). Distilled fennel was found to contain a higher proportion of antioxidant phenolic compounds than non-distilled plant material. 

The impact of plant products on the metabolism of synthetic dmgs results from the inhibition or activation of cytochrome P-450 (CYP) enzymes. Evaluation of the potential activation of CYP by administration of natural plant products or dietary supplements is important for prediction of interactions between their components and dmgs. Therefore, attention is directed to research on the impact of products available on the food market known as natural non-nutritive substances on dmg absorption. Non-nutritive dietary components are mainly secondary plant metabolites, which include, among others, phenolic compounds such as phenolic acids and flavonoids. The health effects of non-nutritive substances are not yet known. So far, there is no answer on the extent to which they are absorbed and metabolized by the body, and there is no information on the permitted daily intake for these compounds. This information is particularly important because certain non-nutritive natural substances are simultaneously considered to be anti-nutritional factors, mainly because they inhibit digestion and reduce the bioavailability of nutrients or dmgs. It is also possible that they form undesirable interactions with dmgs. The positive health effects of non-nutritive natural substances are not only attributed to their antioxidant properties. These substances are involved in various metabolic... 

At present, the percentage contribution of vitamins to the cancer-protective activity of vegetables or fruits is unknown. In this paper, we present results suggesting an involvement of naturally occurring phenolics in the prevention of genotoxicity and carcinogenicity. Since the number of phenolics in various plants is staggering and the discussion of their beneficial or toxic effects is beyond the scope of any short review, we have focused on non-flavonoid simple phenolics (C6), phenolic acids (C6-C1), cinnamic acid and related compounds (C6-C3). 

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