Shiow Y. Wang

Fruit Quality, Antioxidant Capacity, and Flavonoid Content of Organically and Conventionally Grown Blueberries

The effect of cultivation practices on fruit quality and antioxidant capacity in highbush blueberries var. Bluecrop (Vaccinium corymbosum L.) was evaluated from random samples of commercial late harvest fields in New Jersey. Results from this study showed that blueberry fruit grown from organic culture yielded significantly higher sugars (fructose and glucose), malic acid, total phenolics, total anthocyanins, and antioxidant activity (ORAC) than fruit from the conventional culture. In organically cultured fruit, the average values for the ORAC, total anthocyanins, and total phenolic content were 46.14 micromol of Trolox (TE)/g of fresh weight (fwt), 131.2 mg/100 g of fwt, and 319.3 mg/100 g of fwt, respectively. In conventionally cultured fruit, the average values for the ORAC, total anthocyanin, and total phenol content were 30.8 micromol of TE/g of fwt, 82.4 mg/100 g of fwt, and 190.3 mg/100 g of fwt, respectively. The organic culture also produced fruit with higher contents of myricetin 3-arabinoside, quercetin 3-glucoside, delphinidin 3-galactoside, delphinidin 3-glucoside, delphinidin 3-arabinoside, petunidin 3-galactoside, petunidin 3-glucoside, and malvidin 3-arabinoside than conventional culture. There was a significant correlation between the ORAC values and total phenolics and total anthocyanins. These results indicate that even though there were variations in phytonutrient content among individual farms within each cultural system, significant differences between two cultivation practices were evident.

Effect of cultural system and essential oil treatment on antioxidant capacity in raspberries.

The effects of cultural system and essential oil treatment on antioxidant capacities in raspberries were evaluated. Raspberries were hand-harvested from organic and conventional farms in Maryland, USA, and were treated with essential oil including carvacrol, anethole, cinnamic acid, perillaldehyde, cinnamaldehyde, and linalool. Results from this study showed that raspberries grown from organic culture exhibited higher value of antioxidant capacities and individual flavonoids contents. Moreover, the organic culture also enhanced the activities of antioxidant enzymes. In addition, essential oil treatments promoted the antioxidant enzymes activities and antioxidant capacities of raspberries, and the most effective compound was perillaldehyde. In conclusion, raspberries produced from organic culture contained significantly higher antioxidant capacities than those produce from conventional culture. Postharvest essential oil treatments have positive effect on enhancing antioxidant capacities in raspberries from both organic and conventional cultures.

Delphinidin induces necrosis in hepatocellular carcinoma cells in the presence of 3-methyladenine, an autophagy inhibitor.

The present study was performed to determine whether anthocyanins could trigger different modes of cell death in different cancers. It was found that whereas cyanidin-3-rutinoside and delphinidin could induce apoptosis in leukemia cells, they caused growth retardation in hepatocellular carcinoma cells (HCC), which was accompanied with a significant cellular vacuolization. The latter was likely caused by macroautophagy and was completely suppressed by 3-methyladenine, an inhibitor of class III phosphoinositide 3-kinase that is important for autophagy activation, and by bafilomycin A1, which blocks lysosomal degradation. Delphinidin induced significant lipidation of LC3, an indication of macroautophagy, which was also suppressed by 3-methyladenine. Macroautophagy was required for the survival of delphinidin-treated HCC cells as inhibition with 3-methyladenine led to massive necrosis without caspase activation. Thus, anthocyanins could induce different modes of cell death for different cancers. Furthermore, anthocyanins could be used in combination with a macroautophagy inhibitor for treating cancers such as HCC.

Ellagic Acid Enhancement in Strawberries

Ellagic acid is a naturally occurring phenolic constituent of plants, including many that are important in our diet. Interest in ellagic acid has increased greatly during the past decade due to its effectiveness as an antimutagen and its potential as an inhibitor of chemically induced cancer. Much has been learned concerning the diverse clinical attributes of ellagic acid, but relatively little is known about its physiological, genetic, and ecological aspects and its ability to form derivatives (ellagitannins) in the plant.