Skin-whitening mechanism of cumin (Cuminum cyminum L.) extract.

Skin-whitening effect is closely linked with the melanogenesis inhibitory activity and free radical scavenging capacity. The purpose of the present study was to evaluate the skin-whitening effect of cumin (Cuminum cyminum L.) extract. The whitening activity was evaluated by cell-free mushroom tyrosinase assay, free radical scavenging assay, cell viability assay, cellular tyrosinase assay and melanin content assay using B16F10 murine melanoma cells. The results showed that cumin extract exhibited concentration-dependent inhibitory effect on both monophenolase and diphenolase activities of mushroom tyrosinase (IC50 values of 1.027mg/mL and 0.977mg/mL, respectively). Kinetic study on diphenolase showed that the cumin extract was a reversible mixed-type inhibitor, and the inhibition constant (KI) was determined to be 0.62mg/mL. In addition, cumin extract significantly suppressed melanin production and cellular tyrosinase activity of B16F10 melanoma cells in a concentration and time dependent manner without cytotoxicity. Moreover, cumin extract exerted strong scavenging capacity on DPPH, hydroxyl and superoxide anion radicals. Taken together, these results strongly suggest that cumin is a potential skin-whitening agent for the cosmetic industry.

Diuron effects on photosynthesis and vertical migration of microphytobenthos: Potential rapid bioassessment of herbicide toxicity in coastal sediments.

The effects of herbicide diuron on photosynthesis and vertical migration of intertidal microphytobenthos (MPB) assemblages were investigated using chlorophyll fluorometry. The results shown diuron ≤ 60 µg L-1 had no obvious effect on MPB vertical migration during 24 h indicated by consistent rhythm. Low concentration of 10 µg L-1 diuron had no significant influence on MPB photosynthesis throughout, however, high concentrations of 40, 50, and 60 µg L-1 had significant impacts exhibited by decreased parameters of maximum relative electron transport rate (rETRmax), maximal PS II quantum yield (Fv/Fm) and non-photochemical quenching (NPQ). For middle concentrations of 20 and 30 µg L-1, above decreased 3 parameters recovered sooner or later after 2 h or 16.5 h. Comparatively, rETRmax, Fv/Fm and NPQ are concentration dependent and more sensitive than other parameters in assessing diuron toxicity. This study revealed the potential of using MPB assemblages and chlorophyll fluorometry for rapid assessing diuron toxicity in coastal sediments.

[Production of Single Cell Protein from Chinese Medicinal Herb Residues by Solid-State Fermentation].

Objectives: To take full advantage of the Chinese medicinal herb residues, the conditions on fermentation of single cell protein feed were studied. Methods: First,the type of Chinese medicinal herb residues and the microbial strain were screened. Then, the single factor and orthogonal experiments were used to investigate the amount of residue, water and urea. Results: The results showed that the protein content was 20. 98% which was highest when Erlong Zuoci pills residue and Aspergillus niger were applied. When the amount of residue was 20 g, urea was 0. 35%,water was 200%,the content of protein increased from 9. 79% to 21. 35%,and the rate of increasing of protein reached to 118. 1%. The effect order of various factors on the protein content was the amount of urea > the amount of water > the amount of residue. Conclusion: Using the microbial fermentation can improve the single cell protein content in the Chinese medicinal herb residues, the results can provide a scientific basis for development and application of the downstream products of Chinese herbal medicine.

[Effects of remote preconditioning induced by skeletal muscle ischemia on myocardial cells apoptosis and roles of opioid receptors in pigs].

AIM: To investigate the effect on myocardial apoptosis and Bcl-2/Bax induced by remote preconditioning (RP) and to discuss the hypothesis from opioid receptors in pigs. METHODS: Skeletal muscle ischemia was performed in pigs by occlusion of the femoral artery (FAO) for 15 min followed by a 10 min of reperfusion. Infarction of the heart was induced by 40 min of left anterior descending coronary artery (LAD) occlusion followed by 120 min reperfusion. In the RP model induced by FAO, the role of opioid receptors was investigated by using antagonist of the opioid receptors (naloxone). The signal transduction pathway of RP was investigated by using hexamethonium. Apoptosis of left ventricular samples from nonischemic and ischemic areas was detected in situ with end-labeling (TUNEL) method and measured by flow cytometry. Bcl-2 and Bax was also measured by flow cytometry. RESULTS: (1) The apoptosis rate in ischemic myocardium in RP group measured by flow cytometry was lower (4.43% +/- 0.74%) compared with that in CONT group (15.4% +/- 1.15%), but Bcl-2/Bax was higher (1.36 +/- 0.09, CONT group: 0.56 +/- 0.08). (2) The protective effect could be prevented by naloxone used before RP protocol (apoptosis rate: 13.0% +/- 0.56% and Bcl-2/Bax: 0.69 +/- 0.18, P < 0.05). (3) Naloxone had no effect on apoptosis rate in CONT group. (4) Hexamethonium used before RP protocol had no effect on apoptosis rate and bcl-2/bax. Apoptotic cardiomyocytes detected in TUNEL correspond to the above. CONCLUSION: RP induced by skeletal muscle ischemia could prevent myocardium from apoptosis, in which Bcl-2 and Bax might take part in regulation and control. Furthermore opioid receptors could take part in triggering the course and a neuronal signal transmission from the remote area to heart could be excluded.