东北藿香挥发油化学成分分析

采用气相色谱、气相色谱─质谱联机的分析方法,分析了东北藿香挥发油的化学成分,并从中确定了１５种化合物,鉴定组成占挥发油总量的９８６％,其主要组成是百里香醌（＞７０％）。东北藿香挥发油含量高（０５１％鲜重）,香气持久独特、稳定性好,是很好的食用和日用香精。     

Thymoquinone enhances the activities of enzymes related to energy metabolism in peripheral leukocytes of diabetic rats

The aim of this study was to examine the effect of glycemic control using thymoquinone (TQ) on energy metabolism related enzymes in leukocytes of streptozotocin (STZ)-induced diabetic rats. The treatment of both TQ and insulin commenced 4 weeks after induction of diabetes. Plasma glucose, cholesterol and triglycerides levels were significantly reduced after TQ treatment, whereas immunoreactive insulin (IRI) showed significant increase. The activities of malate dehydrogenase (MDH) in cytosolic and mitochondrial fractions of peripheral blood leukocytes were significantly higher in rats treated with TQ and insulin as compared to that in diabetic controls. On the other hand the activities of lactic dehydrogenase (LDH) showed no significant changes between groups. ML ratio (cytosolic MDH/LDH specific activity ratio) was restored to those in the control rats. The results of this study demonstrate that TQ significantly increased insulin level and the activities of cytosolic and mitochondrial MDH in leukocytes of STZ-diabetic rats.     

Anti-angiogenic effect of thymoquinone on breast cancer

AIM: To investigate the anti-angiogenic effect of thymoquinone on human breast cancer and the possible mechanism. METHODS: The activities of human umbilical vein endothelial cells (HUVECs) and human breast cancer MCF-7 cells were assessed by CCK-8 assay. The apoptotic rate was measured by flow cytometry. Furthermore, the assay of capillary tube formation was used to observe the effect of thymoquinone on the tube formation of HUVECs. The protein levels of cleaved caspase-3, p-ERK and p-AKT were detected by Western blot. MCF-7 cells were subcutaneously injected into nude mice to establish breast xenograft tumors. After 3 weeks of implantation, the mice were randomized into control group and thymoquinone group. After the mice were sacrificed, immunohistochemistry was used to detect the expression of CD31 in the tumors, and the TUNEL test kit was used to explore cell apoptosis in the tumor tissues. RESULTS: Thymoquinone at concentrations of 20~80 nmol/L exerted no growth inhibitiory effect on MCF-7 cells. However, the cell viability of HUVECs were (66.1±8.3)％, (53.7±3.4)％ and (41.6±4.9)％ when the concentrations of thymoquinone were 20, 40 and 80 nmol/L, respectively. The apoptotic ratio of MCF-7 cells were (2.6±0.3)％, (2.4±0.3)％ and (4.6±0.4)％ and the apoptotic ratio of HUVECs were (21.5±3.7)％, (23.8±2.9)％ and (27.8±3.1)％ when the concentrations of thymoquinone were 20, 40 and 80 nmol/L, respectively. HUVECs were more sensitive to thymoquinone-induced apoptosis and inhibition in the cell activity than MCF-7 cells. Incubation of HUVECs with diffe-rent concentrations of thymoquinone (20, 40 and 80 nmol/L) for 1 h decreased their tube formation capacity (P<0.05). The protein level of cleaved caspase-3 was up-regulated, but the phosphorylation of AKT and ERK were inhibited in a concentration-dependent manner. The immunohistochemical analysis of CD31 showed significant difference of the integral absorbance between control group and thymoquinone group, and the TUNEL-positive cells in thymoquinone group was significantly more than that in control group. CONCLUSION: Thymoquinone has the anti-angiogenic effect on breast cancer both in vitro and in vivo, which may be related to the decreases in p-ERK and p-AKT.     

Thymoquinone reduces hepatic glucose production in diabetic hamsters

The aim of this study was to elucidate the mechanisms underlying the glucose lowering effects of thymoquinone in streptozotocin (STZ)-induced diabetic hamsters in terms of hepatic glucose production. Diabetes was induced by intraperitoneal injection of 65 mg/kg body weight of STZ. Treatment with thymoquinone commenced 4 weeks after induction of diabetes at a daily dose of 50 mg/kg body weight by gastric gauge. Blood glucose and glycated hemoglobin levels were significantly reduced depending on periods of the treatment. Thirty days after commencement of thymoquinone-treatment, hepatocytes were isolated using collagenase to determine liver glucose production. Glucose production after 2 h incubation of the isolated hepatocytes with gluconeogenic precursors (alanine, glycerol and lactate) was significantly lower in hamsters treated with thymoquinone as compared to that in vehicle controls. The results of this study demonstrate that the antidiabetic action of thymoquinone is at least partially mediated through a decrease in hepatic gluconeogenesis.     

Supercritical carbon dioxide (SC-CO2) extraction of Nigella sativa L. oil using full factorial design

In this study, Nigella sativa L. oil was extracted using supercritical carbon dioxide with full factorial design to determine the best extraction condition (pressure, temperature and dynamic extraction time) for obtaining an extract with high yield, antioxidant activity and thymoquinone (TQ) quantity. The maximum thymoquinone content in the highest overall yield was achieved through SC-CO₂ extraction condition of 150 bar, 40 °C, 120 min with the value of 4.09 mg/ml. The highest SC-CO₂ extraction yield was 23.20% which obtained through extraction condition of 350 bar, 60 °C and 120 min. The extraction conducted at 350 bar, 50 °C, 60 min showed the lowest IC₅₀ value (highest antioxidant activity) of 2.59 mg/ml using DPPH radical scavenging activity method. Fatty acid composition of the extracted oil with highest radical scavenging activity was obtained by gas chromatographic analysis.