ABSTRACT
During the 29th Chinese National Antarctic Research Expedition (CHIANRE), individual particle samples were collected from South China to Antarctic during November 2012 to April 2013. A transmission electron microscopy with energy-dispersive X-ray spectrometry (TEM-EDS) was employed to analyze the morphology, mixing state, composition, and relative abundances of individual aerosol particles. Atmospheric particles were classified into four types:sea salt, mineral, S-rich and C-rich. Sea salt aerosols (SSA) were dominant in the marine particles from South China to Antarctic, and they were further divided into three sub-types:fresh SSA, partially aged SSA, and fully aged SSA. Partially and fully aged SSA accounted for 86% of total SSA number. Interestingly, surface of partially aged SSA and fully aged SSA contained abundant rod-like Na2SO4. Mineral dust particles increased in the coastal areas which were influenced by continental air. In addition, we found that S-rich particles were abundant at two sampling sites (the middle eastern of Indian Ocean and Antarctic inland). The back trajectories of air masses indicated that these S-rich particles were mainly formed via the oxidation of dimethyl sulfide (DMS) emitted from the marine phytoplanktons. Our study suggests that the SSA aging process in the South Hemisphere atmosphere was controlled by the DMS which is different from the SSA aging under the influence of anthropogenic pollutants in the North Hemisphere.
ABSTRACT
Phenolics in black soybean seed coat (BSSC) are considered to be responsible for the health benefits of black soybean. BSSCs of 60 Chinese varieties were examined for phenolic contents, anthocyanin profiles, and antioxidant activity. Total phenolic and condensed tannin contents ranged from 512.2 to 6057.9 mg gallic acid equivalents/100 g and from 137.2 to 1741.1 mg (+)-catechin equivalents/100 g, respectively. Six anthocyanins (delphinidin-3-glucoside, cyanidin-3-galactoside, cyanidin-3-glucoside, petunidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside) were detected by HPLC. Total anthocyanin contents (TAC) were from 98.8 to 2132.5 mg/100 g, and cyanidin-3-glucoside was the most abundant anthocyanin in all varieties, with a distribution of 48.8-94.1% of TAC. Antioxidant properties detected by DPPH, FRAP, and ORAC methods all showed wide variations ranging from 4.8 to 65.3 µg/100 mL (expressed as EC(50)), from 17.5 to 105.8 units/g, and from 42.5 to 1834.6 µmol Trolox equivalent/g, respectively. Sixty varieties were classified into four groups by hierarchical clustering analysis, and group 4 consisting of nine varieties had the highest phytochemicals content and antioxidant activity.
