This study was aimed at determining the effects of selenium on the contents of vitamin C, amino acid, total water-soluble solids and tea polyphenol, and whether the antioxidant activity of selenium-enriched green tea is enhanced compared with regular green tea by linoleic acid oxidation and the lard oxidation method. The contents of selenium, vitamin C and tea polyphenol in green teas were greatly increased by foliar application of selenium-enriched fertilizer. No significant differences of the contents of vitamin C, amino acid and tea polyphenol were observed between green tea treated with sodium selenite and that without selenium. The selenium-enriched green tea exhibited significantly higher antioxidant activity than regular green tea, both in linoleic acid oxidation and in the lard oxidation system. These results suggest that the antioxidant activity of green tea is significantly enhanced by the combination of selenium and green tea constituents compared with that of regular green tea.

Atomic fluorescence spectrophotometry was used to determine the selenium (Se) concen-tration in 30 rice products of different species from Southern China. The Se level ranged from 0.015 to 0.0461μgg-1. Considering the average daily individual consumption of rice products in Southern China, the average dietary intake of Se supplied by this source is only 6-18μg day-1 for an adult. This low Se intake from rice products is mainly responsible for the low total Se intake of inhabitants in Southern China. Foliar spraying ofSe-enriched fertiliser or sodium selenite with 14-18g Seha-1 in the heading stage of rice growth increased the Se content to 0.178-0.421μgg1 in rice products. The concentration and amount ofSe-enriched fertiliser can be varied to achieve an optimum concentration of Se in rice products. The authors suggest that these Se-enriched rice products can contribute an increase in Se intake of 50-100μgday-1 on average if their Se concentration is controlled in the region of 0.15-0.50μg g-1.

To increase the selenium content of tea produced in areas of China poor in selenium, sodium seleite was added to tea garden soil or was sprayed onto tea leaves. Effects of selenium on green tea quality and the anino acid composition of tea protein were studied. Selenium-enriched green tea and poor selenium green tea were extracted with hot water (100℃) at a 1:50 ratio (w/v). The tea ldaf exracts were stored 30℃ for 12h, the colour changes of selenium-enriched green tea extact were more stable than with poor selenium green tea extract. The teas were packaged in polypropylene plastic bags and then stored at room temperature for 90d. The reduced ratio of vitamin C inselenium-enriched green tea was 21% compared with poor selenium fcontent green tea at 52%. These results demonstrated that selenium-enriched green tea produced a more desirable quality than poor selenium green tea. The total amino acid amounts, essential amino acid, methionine acid and cystine acid content of differetn selenium enriched green tea protein were increased by 8.3%-14.8%, 8.8%-14.8%, 6.0%-8.7%and 39%-96%, respectively, comparedwith the low selenium green tea. Green tea quality was raised by selenium tratment.

This research was to determine the effect of foliar application of selenium on increasing the antioxidant activity of tea harvested during the early spring tea producing season using a R,R-diphenyl-

Selenium fertilizer was foliar applied to determine the effects of antioxidant activity of seleniumenriched rice assessed by R,R-diphenyl-

The polysaccharide and flavonoid concentrations of two-, three-, and four-year-old Aloe vera were determined, and their antioxidant activities were evaluated compared to BHT and R-tocopherol by the DPPH radical scavenging method and the linoleic acid system at 100

Five compounds oxidizing canine erythrocytes were isolated from an aqueous ethanol garlic extract by sillica gel column chromatograpjhy and preparative thin-layer chromatography. On the basis of nuclear magnetic resonance, infraed spectroscopy, and mass spectrometry, they were identified as three known compounds: bis-2-propenyl trisulfide (1), bis-2-propentl tetrasulifide (2), and bis-2-propenyl pentasulfide (3) as well as two novel compounds, bis-2-propenyl tetrasulifide (4) and transsulfunic acid alyl ester 3-allyisulfanyl-allyl ester (5)-A mixture of compounds 1-3 and compounds 4 and 5 induced methemoglobin formation in canine erythrocyte suspension in vitro resulting in the oxidation of canine erythrocytes. These groups of characteristic organosulfur compounds contained in gralic probably contrbute to oxidations in blodd. The constituents of garlic have the potential to oxidize erythrocytes and hemoglobin, suggesting that foods containing quantities of garlic have the potential to oxidize erythrocytes and hemoglobin, suggesting that foodds containing quantities of garlic should be avoiede for feeding dogs.

activities of extracts derived from sesame seed by supercritical carbon dioxide (SC-CO2) extraction and by n-hexane were determined using R,R-diphenyl-â-picylhydrazyl (DPPH) radical scavenging and linoleic acid system methods. The highest extracted yield was given at 35℃, 40MPa, and a CO2 flow rate of 2.5mL min-1 by an orthogonal experiment. The yields of extracts increased with increasing pressure, and yields at 40 and 30MPa were higher than that by solvent extraction at 46.50%. Results from the linoleic acid system showed that the antioxidant activity follows the order: extract at 3℃, 20MPa>BHT>extract at 55℃, 40MPa>extract at 55℃, 30MPa>Trolox>solvent extraction>R-tocopherol. The SC-CO2 extracts exhibited significantly higher antioxidant activities comparable to that by n-hexane extraction. The extracts at 30MPa presented the highest antioxidant activities assessed in the DPPH method. At 20MPa, the EC50 increased with temperature, which indicated that the antioxidant activity was decreased in a temperature-dependent manner. The significant differences of antioxidant activities were found between the extracts by SCCO2 extraction and n-hexane. However, no significant differences were exhibited among the extracts by SC-CO2 extraction. The vitamin E concentrations were also significantly higher in SC-CO2 extracts than in n-hexane extracts, and its concentrations in extracts corresponded with the antioxidant activity of extracts.

Two experiments were conducted to study the effect of the application of selenium on the selenium content of soybean and its products in two counties with selenium-deficient soil. Selenium-enriched soybean was produced by the application of sodium selenite and Se-enriched fertilizer. The selenium contents of soybeans, soybean protein and okra were determined by hydride-generation atomic fluorescence spectrometry. The results showed that the selenium contents of soybean, soybean protein, and okra were significantly increased by the application of sodium selenite and selenium-enriched fertilizer. Foliar application of selenium provided a higher efficiency for increasing the selenium content of soybean than soil application. Significant differences were found in that soybean cultivars exhibited different accumulation of selenium. There was no remarkable difference in soybean yield, soybean protein, and lipid between selenium and control. The selenium-enriched protein derived from selenium-enriched soybean could be used as a functional ingredient and soybean okra as a selenium-enriched feed for animals for increasing selenium intake.