The objective of the present study was to determine the total phenol and flavonoid contents and to evaluate the antioxidant potential, of different solvent extracts (ethyl acetate, n-butanol, chloroform, and water) from Robus idaeus in various radical scavenging models (DPPH activity, superoxide dismutase (SOD) activity, reducing power, and nitrite scavenging activity), along with their antimicrobial potential. Measurement of total phenol and flavonoid content of the ethyl acetate extract of R. idaeus was found to be significantly higher than those of the other extracts. The ethyl acetate extract (at a concentration of 1,000 μg/mL) showed significantly higher reducing power and DPPH radical scavenging activity as compared to the other extracts. Results were dose-dependent. Moreover, the ethyl acetate extract of R. idaeus (1,000 μg/mL) showed potent antioxidant efficacy (85.5±1.18%) as evidenced by nitrite scavenging ability at pH 1.2. All solvent extracts of R. idaeus showed lower SOD-like activity (13.72~20.54%). In addition, the antimicrobial activity of all solvent extracts except water extract showed strong inhibition (inhibitory zones in mm) of Staphylococcus aureus (19.40±1.00 mm) and Bacillus cereus (20.50±0.21 mm) growth. In particular, ethyl acetate extracts (100 mg/mL) showed antimicrobial activity comparable to that of tetracycline (0.01 mg/mL), which was used as a positive control. The results of this study indicate that the ethyl acetate extract of R. idaeus is a natural antioxidant and antimicrobial, with enriched phenols and flavonoids concentration, that has potential in the development of health-enhancing food products.

The physical and chemical properties of prestellar cores, especially massive ones, are still far from being well understood due to the lack of a large sample. The low dust temperature (< 14 K) of Planck cold clumps makes them promising candidates for prestellar objects or for sources at the very initial stages of protostellar collapse. We have been conducting a series of observations toward Planck cold clumps (PCCs) with ground-based radio telescopes. In general, when compared with other star forming samples (e.g. infrared dark clouds), PCCs are more quiescent, suggesting that most of them may be in the earliest phase of star formation. However, some PCCs are associated with protostars and molecular out ows, indicating that not all PCCs are in a prestellar phase. We have identied hundreds of starless dense clumps from a mapping survey with the Purple Mountain Observatory (PMO) 13.7-m telescope. Follow-up observations suggest that these dense clumps are ideal targets to search for prestellar objects.

The symbiotic star V1016 Cygni, a detached binary system consisting of a hot white dwarf and a mass-losing Mira variable, shows very broad emission features at around 6825 °A and 7082 °A, which are Raman scattered Ovi  1032, 1038 by atomic hydrogen. In the high resolution spectrum of V1016 Cyg obtained with the Bohyunsan Optical Echelle Spectrograph these broad features exhibit double peak profiles with the red peak stronger than the blue counterpart. However, their profiles differ in such a way that the blue peak of the 7082 feature is relatively weaker than the 6825 counterpart when the two Raman features are normalized to exhibit an equal red peak strength in the Doppler factor space. Assuming that an accretion flow around the white dwarf is responsible for the double peak profiles, we attribute this disparity in the profiles to the local variation of the flux ratio of Ovi  1032, 1038 in the accretion flow. A Monte Carlo technique is adopted to provide emissivity maps showing the local emissivity of Ovi 1032 and Ovi 1038 in the vicinity of the white dwarf. We also present a map indicating the differing flux ratios of Ovi  1032 and 1038. Our result shows that the flux ratio reaches its maximum of 2 in the emission region responsible for the central trough of the Raman feature and that the flux ratio in the inner red emission region is almost 1. The blue emission region and the outer red emission region exhibit an intermediate ratio around 1.5. We conclude that the disparity in the profiles of the two Raman Ovi features strongly implies accretion flow around the white dwarf, which is azimuthally asymmetric.