Antioxidant and Antiproliferative Activities of Common Fruits

Abstract

Consumption of fruits and vegetables has been associated with reduced risk of chronic diseases such as cardiovascular disease and cancer. Phytochemicals, especially phenolics, in fruits and vegetables are suggested to be the major bioactive compounds for the health benefits. However, the phenolic contents and their antioxidant activities in fruits and vegetables were underestimated in the literature, because bound phenolics were not included. This study was designed to investigate the profiles of total phenolics, including both soluble free and bound forms in common fruits, by applying solvent extraction, base digestion, and solid-phase extraction methods. Cranberry had the highest total phenolic content, followed by apple, red grape, strawberry, pineapple, banana, peach, lemon, orange, pear, and grapefruit. Total antioxidant activity was measured using the TOSC assay. Cranberry had the highest total antioxidant activity (177.0 +/- 4.3 micromol of vitamin C equiv/g of fruit), followed by apple, red grape, strawberry, peach, lemon, pear, banana, orange, grapefruit, and pineapple. Antiproliferation activities were also studied in vitro using HepG(2) human liver-cancer cells, and cranberry showed the highest inhibitory effect with an EC(50) of 14.5 +/- 0.5 mg/mL, followed by lemon, apple, strawberry, red grape, banana, grapefruit, and peach. A bioactivity index (BI) for dietary cancer prevention is proposed to provide a new alternative biomarker for future epidemiological studies in dietary cancer prevention and health promotion.

Characterization of the antioxidant properties of phenolic extracts from some citrus peels

“…However, free phenolic extracts from orange peels have the highest DPPH* scavenging ability, but lower than that of free phenolics from some leafy spices in Nigeria (Oboh and Rocha 2007a, b); while bound phenolics from shaddock peels had the least DPPH* scavenging ability. Nevertheless, the trend in the results agree with the phenolic distribution in the citrus peels and many earlier research articles, where correlation were reported between phenolic content and antioxidant capacity of some plant foods (Amic et al 2003;Sun et al 2002;Chu et al 2002).…”

“…Their potent antioxidant activity is due to the redox properties of their hydroxyl groups (Materska and Perucka 2005;Rice-Evans et al 1996;Rice-Evans et al 1997). Phenolics are present in plant in both free and bound forms; bound phenolics mainly in the form of β-glycosides, may survive human stomach and small intestine digestion and reach the colon intact, where they are released and exert their bioactivity (Sosulski et al 1982); while free phenolics are more readily absorbed and thus, exert beneficial bioactivities in early digestion; however, the significance of bound phytochemicals to human health is not clear Sun et al 2002).…”

Optimum extraction Process of polyphenols from the bark of Phyllanthus emblica L. based on the response surface methodology

“…At higher temperature, a higher yield of polyphenols extracted from fruit can be obtained. High-temperature solvent will promote polysaccharides on cell wall to distribute to solvent, and to weaken or undermine the integrity of the cell wall so that more solvent can be contacted with polyphenols [29]. To study the effect of different temperatures…”

Antioxidant and antiproliferative activities of phenolics isolated from fruits of Himalayan yellow raspberry (Rubus ellipticus)

“…A wide variety of fruits such as blueberry, blackberry, raspberry, pomegranate, plum, peach, apple, quince, pear, guava, banana and citrus fruits have been shown to possess high phenolic contents and super antioxidant activities (Wang et al 1996;Gil et al 2002;Kahkonen et al 2001;Moyer et al 2002;Karadeniz et al 2005;Mokbel and Hashinaga 2005;Lim et al 2007;Meda et al 2008). Additionally, fruits phenolics have also been demonstrated to possess strong antiproliferative properties (Johnson et al 2011;Sun et al 2002;Liu et al 2002;Seerama et al 2005). Due to the cancer protective effects, and super antioxidant properties, fruits are gaining world wide interest for the exploration of their polyphenolic contents and their various health promoting properties (Kahkonen et al 2001;Leong and Shui 2002;Moyer et al 2002;Karadeniz et al 2005;Marinova et al 2005;Barreira et al 2008;Lim et al 2007;Meda et al 2008).…”