Fruits physiological effect

As well as the TDF content, the proportion between SDF and IDF is an important nutritional parameter because of the different physiological effects that these exert. Proportions of SDF are characteristically high in fruits and vegetables, although they can differ considerably. SDF is less than 20% of TDF in grape but more than 30% in onion and higher than 50% in fig. 

The present review indicates that while pectin products continue to serve as a well-established food additive for technological purposes, the application of pectins for health benefits has many potential opportunities. In the last few decades, considerable research has been done on the physiological effects of pectin in humans as a water-soluble dietary fiber supplement. Some novel pharmacological activities of pectins and pectic polysaccharides are gaining more attention. Although most natural pectins from fruits and vegetables have not been shown to have these activities, chemical and enzymatic modifications may provide useful tools for producing such products for human health care. 

Today, many of those plants are still used in medicine in Central Asia. Many centuries of herbal use has proven that plants contain substances that have healing power. Folk medicine has also shown that different parts of each plant often have different effects and, therefore, are used for different diseases, for example, roots for one type of disease and the aboveground parts for another. Similarly, leaves, flowers, fruits, and seeds may have different medicinal uses. Active compounds usually accumulate in large amounts in only certain parts of a plant (Wink 1999). The amounts of active substances in a plant, and consequently their physiological effect when taken as a medicine, significantly fluctuate depending on the season of the year, habitat, altitude, yearly cUmatic conditions, soil composition, and other factors (Evans 2002). 

El Ghaouth, A., Arul, J., Wilson, C. Benhamou, N. (1994). Ultrastructural and cytochemical aspects of the effect of chitosan on decay of bell pepper fruit. Physiological and Molecular Plant Pathology, 44, 417-432. 

Vitamin C occurs as L-ascorbic acid and dihydroascorbic acid in fruits, vegetables and potatoes, as well as in processed foods to which it has been added as an antioxidant. The only wholly undisputed function of vitamin C is the prevention of scurvy. Although this is the physiological rationale for the currently recommended intake levels, there is growing evidence that vitamin C may provide additional protective effects against other diseases including cancer, and the recommended dietary allowance (RDA) may be increased in the near future. Scurvy develops in adults whose habitual intake of vitamin C falls below 1 mg/d, and under experimental conditions 10 mg/d is sufficient to prevent or alleviate symptoms (Bartley et al., 1953). The RDA is 60 mg per day in the USA, but plasma levels of ascorbate do not achieve saturation until daily intakes reach around 100 mg (Bates et al., 1979). Most of the ascorbate in human diets is derived from natural sources, and consumers who eat five portions, or about 400-500 g, of fruits and vegetables per day could obtain as much as 200 mg of ascorbate. 

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