Galuteolin, identified in the extract of thymus quinquecostatus flowers, is involved in inhibiting melanin biosynthesis in B16/F10 melanoma cells.

To enhance the skin whitening effect, tyrosinase activity and melanin biosynthesis needs to be suppressed in the skin. To achieve this goal, we examined the extract of Thymus quinquecostatus flowers, and identified a functional ingredient, galuteolin. Galuteolin effectively inhibited melanin biosynthesis in B16/F10 cells, partially suppressing tyrosinase activity. Therefore, this study suggests that galuteolin can be used as a cosmetic ingredient for skin whitening.

Multiclass mycotoxin analysis in edible oils using a simple solvent extraction method and liquid chromatography with tandem mass spectrometry.

A simple and rapid method for the simultaneous determination of 11 mycotoxins - aflatoxins B1, B2, G1 and G2; fumonisins B1, B2 and B3; ochratoxin A; zearalenone; deoxynivalenol; and T-2 toxin - in edible oils was established using liquid chromatography tandem mass spectrometry (LC-MS/MS). In this study, QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe), QuEChERS with dispersive liquid-liquid microextraction, and solvent extraction were examined for sample preparation. Among these methods, solvent extraction with a mixture of formic acid/acetonitrile (5/95, v/v) successfully extracted all target mycotoxins. Subsequently, a defatting process using n-hexane was employed to remove the fats present in the edible oil samples. Mass spectrometry was carried out using electrospray ionisation in polarity switching mode with multiple reaction monitoring. The developed LC-MS/MS method was validated by assessing the specificity, linearity, recovery, limit of quantification (LOQ), accuracy and precision with reference to Commission Regulation (EC) 401/2006. Mycotoxin recoveries of 51.6-82.8% were achieved in addition to LOQs ranging from 0.025 ng/g to 1 ng/g. The edible oils proved to be relatively uncomplicated matrices and the developed method was applied to 9 edible oil samples, including soybean oil, corn oil and rice bran oil, to evaluate potential mycotoxin contamination. The levels of detection were significantly lower than the international regulatory standards. Therefore, we expect that our developed method, based on simple, two-step sample preparation process, will be suitable for the large-scale screening of mycotoxin contamination in edible oils.

Melanogenesis inhibitory effects of methanolic extracts of Umbilicaria esculenta and Usnea longissima.

The primary objective of this study was to assess the in vitro melanogenesis inhibitory effects of methanolic extracts of the edible and medicinal lichens, Umbilicaria (Gyrophora) esculenta and Usnea longissima. The quantities of the total phenolic compounds of methanolic extract of the two lichen extracts were determined to be 1.46% and 2.62%, respectively. In order to evaluate the antioxidative effects of the extracts, we also measured electron donating abilities (EDA) and lipid peroxidation rates. The EDA values measured by the reduction of 1.1''-diphenyl-2-picrylhydrazyl (DPPH) were 72.8% and 80.7% for the extracts, with SC50 (median scavenging concentration) values of 1.29+/-0.05 mg/ml and 1.03+/-0.06 mg/ml, respectively. The rates of inhibition of lipid peroxidation using linoleic acid were 92.1% and 97.3% for the extracts, with IC50 (median inhibitory concentration) values of 0.57+/-0.05 mg/ml and 0.53+/-0.06 mg/ml, respectively. The inhibitory rates of the extracts against tyrosinase were 67.4% and 84.8%, respectively. The extracts were shown to reduce melanin formation in human melanoma cells. Melanin contents in the samples treated with 0.01% and 0.1% U. esculenta were 47.1% and 31.2%, respectively, and those treated with 0.01% and 0.1% Usnea longissima were 51.1% and 34.9%, respectively, whereas a value of 54.0% was registered when ascorbic acid was utilized as a positive control. In addition to direct tyrosinase inhibition, it was determined that the lichen extracts affected the activity of tyrosinase via the inhibition of tyrosinase glycosylation. As a result, the methanolic extracts of U. esculenta and Usnea longissima evidenced melanogenesis inhibitory effects, which occurred via multiple routes.

Antithrombotic activity of methanolic extract of Umbilicaria esculenta.

Antithrombotic activity of methanolic extract of an edible lichen, Umbilicaria esculenta, was evaluated on platelet aggregation in vitro and pulmonary thrombosis in vivo. The extract showed concentration dependent inhibitory effects on platelet aggregation induced by ADP, with IC(50) value of 2.4 mg/mL. Orally administered extract protected mice against thrombotic death or paralysis induced by collagen and epinephrine in a dose dependent manner. It produced a significant inhibition of thrombotic death or paralysis at over 100 mg/kg body weight, while aspirin produced a significant inhibition of thrombosis at 10-20 mg/kg body weight. Mouse tail bleeding time was significantly prolonged by addition of the extract. On the other hand, the extract did not show any fibrinolytic activity and alter coagulation parameters such as activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) in rat platelet. These results suggested that the antithrombotic activity of Umbilicaria esculenta extract might be due to antiplatelet activity rather than anticoagulation activity.

Antiplatelet and antithrombotic activities of methanol extract of Usnea longissima.

The antiplatelet and antithrombotic activities of a methanol extract of a medicinal lichen, Usnea longissima, were investigated on platelet aggregation in vitro and on pulmonary thrombosis in vivo. The extract showed concentration dependent inhibitory effects on ADP-induced platelet aggregation, with an IC50 value of 3.6 mg/mL. Using an in vivo mouse thrombotic model in which mice were challenged with an intravenous injection of collagen and epinephrine mixture, oral administration of the extract prior to the injection produced a significant inhibition of thrombotic death or paralysis at 100-200 mg/kg body weight. Aspirin, a representative antiplatelet drug, produced a significant inhibition of thrombotic death at 10-20 mg/kg body weight. The mouse tail bleeding time was significantly prolonged by the addition of the extract. On the other hand, the extract did not show any fibrinolytic activity or alter the coagulation parameters such as activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) in rat platelets in vitro. These results suggested that the antithrombotic activity of U. longissima extract might be due to antiplatelet activity rather than anticoagulant activity.