Biotransformation and metabolite activity analysis of flavonoids from propolis in vivo.

Propolis is a natural resinous compound produced by bees, mixed with their saliva and wax, and has a range of biological benefits, including antioxidant and anti-inflammatory effects. This article reviews the in vivo transformation of propolis flavonoids and their potential influence on drug efficacy. Despite propolis is widely used, there is little research on how the active ingredients of propolis change in the body and how they interact with drugs. Future research will focus on these interactions and the metabolic fate of propolis in vivo.

Design, Synthesis and Molecular Docking of 1,3,4-Oxadiazole-2(3H)-thione Derivatives Containing 1,4-Benzodioxane Skeleton as Potential FabH Inhibitors.

Fatty acid biosynthesis is essential for bacterial survival. Of these promising targets, ß-ketoacyl-acyl carrier protein (ACP) synthase III (FabH) is the most attractive target. A series of novel 1,3,4-oxadiazole-2(3H)-thione derivatives containing 1,4-benzodioxane skeleton targeting FabH were designed and synthesized. These compounds were determined by 1 H-NMR, 13 C-NMR, MS and further confirmed by crystallographic diffraction study for compound 7m and 7n. Most of the compounds exhibited good inhibitory activity against bacteria by computer-assisted screening, antibacterial activity test and E. coli FabH inhibitory activity test, wherein compounds 7e and 7q exhibited the most significant inhibitory activities. Besides, compound 7q showed the best E. coli FabH inhibitory activity (IC50 =2.45 µΜ). Computational docking studies also showed that compound 7q interacts with FabH critical residues in the active site.

Authentication of Apis cerana Honey and Apis mellifera Honey Based on Major Royal Jelly Protein 2 Gene.

In Asia, honey is mainly produced by Apis mellifera and Apis cerana. However, the price of A. cerana honey is usually much higher than A. mellifera honey. Seeing considerable profits, some dishonest companies and beekeepers mislabel A. mellifera honey as A. cerana honey or incorporate A. mellifera honey into A. cerana honey. In the present study, we developed methods to discriminate A. cerana honey from A. mellifera honey based on the MRJP2 (major royal jelly protein 2) gene. Two pairs of species-specific primers were designed. The amplification products of A. cerana and A. mellifera were 212 and 560 bp, respectively. As little as one percent incorporation of A. mellifera honey in the mixture can be detected by duplex PCR. Additionally, another method based on the melt curve analysis using the same primers was also developed, allowing a rapid discrimination of real-time PCR product of different species. Our study shows that the entomological authentication of honey samples can be identified by nuclear genes other than mitochondrial genes and this extends the possibility of gene selection in identification. The authentication system we proposed could be a useful tool for discriminating A. cerana honey from A. mellifera honey.

[Effects of methyl jasmonate on metabolism of topical alkaloids and expression of relate genes in Atropa belladonna].

Hyoscyamine and scopolamine are important secondary metabolites of tropane alkaloid in Atropa belladonna with pharmacological values in many aspects.In this study, the seedlings of A.belladonna were planted by soil culture and treated with different concentrations of methyl jasmonate (MeJA). The contents of hyoscyamine and scopolamine,the upstream products in alkaloid synthesis,and the expression levels of key enzyme genes PMT, TR Ⅰ and H6H in secondary metabolites of A. belladonna seedlings were measured to clarify the mechanism of MeJA regulating alkaloids synthesis.The results showed that MeJA(200 µmol·L⁻¹) treatment was more favorable for the accumulation of alkaloids.The content of putrescine was almost consistent with the change of key enzymes activities in the synthesis of putrescine,the both increased first and then decreased with the increased MeJA concentration and the content of putrescine reached the highest at 200 µmol·L⁻¹ MeJA.Further detection of gene expression of PMT, TR Ⅰ and H6H in TAs synthesis pathway showed that no significant trend in PMT gene expression levels.The expression levels of TR Ⅰ and H6H in leaves and roots under 200 µmol·L⁻¹ MeJA were the highest.It can be speculated that the regulation of the formation of hyoscyamine and scopolamine by MeJA mainly through affecting the expression of key enzyme genes.Appropriate concentration of MeJA increased the gene expression of TR Ⅰ in both leaves and roots as well as H6H in roots,promoting the accumulation of alkaloids and the conversion of hyoscyamine to scopolamine.

[Effects of nitrogen form on accumulation of alkaloids and expression of relative genes in Atropa belladonna].

Hyoscyamine and scopolamine are two main alkaloids in Atropa belladonna with great medicinal value. In this paper, the contents of hyoscyamine and scopolamine, the upstream products in alkaloid synthesis, and the expression levels of key enzyme genes PMT, TRⅠ and H6H in secondary metabolism of A. belladonna seedlings were measured to clarify the mechanism of nitrogen forms regulating alkaloids synthesis.The results showed that the 50/50 (NH⁺4/NO⁻3) treatment was more favorable for the accumulation of alkaloids and the conversion of hyoscyamine to scopolamine. The content of putrescine was almost consistent with the change of key enzymes activities in the synthesis of putrescine, they both increased with the rise of ammonium ratio, reaching the highest at 75/25 (NH⁺4/NO⁻3). The detection of signaling molecule nitric oxide (NO) showed that the NO concentration decreased with the decrease of nitrate proportion. Further detection of gene expression levels of PMT, TRⅠ and H6H in TAs synthesis pathway showed that a certain amount of ammonium promoted the expression of PMT and H6H in roots. When the ratio of ammonium to nitrate was 50/50, PMT, TRⅠ and H6H in leaves and roots had higher expression levels. It can be speculated that the regulation of the formation of hyoscyamine to scopolamine by nitrogen forms mainly through affecting the expression of key enzyme genes. 50/50 (NH⁺4/NO⁻3) treatment increased the gene expression of TRⅠ in both leaves and roots as well as PMT and H6H in roots, promoting the synthesis of putrescine to hyoscyamine and the conversion of hyoscyamine to scopolamine.

Lipopolysaccharide Enhances Beta2-Glycoprotein I Activation of Nuclear Factor κB in Liver Cancer Cells.

BACKGROUND: Beta2-glycoprotein I (ß2GPI) is a highly abundant glycoprotein in plasma. Our previous study demonstrated strong ß2GPI expression in hepatitis B-related hepatocellular carcinoma (HCC) tissue and the combination of ß2GPI and hepatitis B surface antigen (HBsAg) was shown to significantly activate the nuclear factor kappa B (NF-κB). To investigate whether lipopolysaccharide (LPS) enhances ß2GPI activation of NF-ßB and the expression of downstream factors (e.g., tumor necrosis factor alpha, TNF-α; interleukin-1 beta, IL-1ß; alpha-fetoprotein, AFP) in the human hepatoma cell line, SMMC-7721. METHODS: Experimental samples were divided into 4 groups as follows: Group A--blank cell group (SMMC-7721); group B--low, medium, and high LPS concentration groups (1 ng/mL; 10 ng/mL; and 100 ng/mL, respectively); group C--ß2GPI transfected group; and group D--ß2GPI + low, medium, or high concentrations from the LPS affected group. Activation of NF-κB was evaluated using laser scanning confocal microscopy. Expression of downstream factors was measured by ELISA. RESULTS: Degrees of NF-κB activation in groups B, C, and D were varied. NF-κB activation in group D was the most significant, and the expressions of downstream factors, TNF-α and IL-1ß, were the highest level of activation among the groups (p < 0.05), showing an LPS dose-dependency. CONCLUSIONS: LPS enhanced the signal transduction of ß2GPI in liver cancer cells leading to activation of NF-κB, which triggered downstream signal transduction and increased the expression of downstream factors. This suggests that LPS enhancement of ß2GPI signal transduction may play a role in promoting the development of liver cancer.

Prevalence and characterization of hepatitis B and C virus infections in a needle-sharing population in Northern China.

BACKGROUND: The epidemiologies of hepatitis C virus (HCV) and hepatitis B virus (HBV) infections in specific populations in certain areas of China are poorly understood. A pilot survey of HCV/HBV infections was carried out in villages in Kuancheng County, Heben Province, where injection of sodium benzoate or amphetamines using shared needles has been a common practice. The aims of this study were to analyze the endemicity and characterize HCV/HBV infections in this population. METHODS: Data on demographic characteristics and drug abuse were collected from individuals who signed informed consent forms. Serum HCV antibody (anti-HCV), hepatitis B surface antigen (HBsAg), and hepatitis B core antibody (anti-HBc) were measured in all participants. HCV RNA was measured in samples positive for anti-HCV using real-time polymerase chain reaction. RESULTS: Among 852 participants from 11 villages, 49.9% had used sodium benzoate or amphetamine at least once, by intravenous injection. The overall prevalence of anti-HCV, HCV RNA, anti-HBc, HBsAg, and HCV/HBV co-infection was 37.1%, 26.6%, 67.7%, 10.7%, and 30.0%, respectively. Two-hundred-twenty-three of 227 (98.2%) participants positive for HCV RNA were aged >40 years. Co-infection was related to sex, age, number of injections, and time from first injection. The rate of spontaneous HCV RNA clearance was 28.2% (89/316), and was related to the number of injections, time from first injection, and HBsAg positivity. However, HBsAg was related to the anti-HBc signal/cut-off ratio rather than to the above parameters. Trend tests demonstrated that the prevalence of anti-HCV, HCV RNA, and anti-HBc was related to the number of injections (P < 0.001), while HBsAg prevalence was not (P = 0.347). CONCLUSIONS: The prevalence of HCV and HBV infection is likely to be high among individuals older than 40 years in areas of needle sharing, and one-time screening for HCV infection should be offered to these populations.

Deforestation and fragmentation of natural forests in the upper Changhua watershed, Hainan, China: implications for biodiversity conservation.

Hainan, the largest tropical island in China, belongs to the Indo-Burma biodiversity hotspot. The Changhua watershed is a center of endemism for plants and birds and the cradle of Hainan's main rivers. However, this area has experienced recent and ongoing deforestation and habitat fragmentation. To quantify habitat loss and fragmentation of natural forests, as well as the land-cover changes in the Changhua watershed, we analyzed Landsat images obtained in 1988, 1995, and 2005. Land-cover dynamics analysis showed that natural forests increased in area (97,909 to 104,023 ha) from 1988 to 1995 but decreased rapidly to 76,306 ha over the next decade. Rubber plantations increased steadily throughout the study period while pulp plantations rapidly expanded after 1995. Similar patterns of land cover change were observed in protected areas, indicating a lack of enforcement. Natural forests conversion to rubber and pulp plantations has a general negative effect on biodiversity, primarily through habitat fragmentation. The fragmentation analysis showed that natural forests area was reduced and patch number increased, while patch size and connectivity decreased. These land-cover changes threatened local biodiversity, especially island endemic species. Both natural forests losses and fragmentation should be stopped by strict enforcement to prevent further damage. Preserving the remaining natural forests and enforcing the status of protected areas should be a management priority to maximize the watershed's biodiversity conservation value.

Recent advances in the chemical composition of propolis.

Propolis is a honeybee product with broad clinical applications. Current literature describes that propolis is collected from plant resins. From a systematic database search, 241 compounds were identified in propolis for the first time between 2000 and 2012; and they belong to such diverse chemical classes as flavonoids, phenylpropanoids, terpenenes, stilbenes, lignans, coumarins, and their prenylated derivatives, showing a pattern consistent with around 300 previously reported compounds. The chemical characteristics of propolis are linked to the diversity of geographical location, plant sources and bee species.

Identification of catechol as a new marker for detecting propolis adulteration.

Adulteration of propolis with poplar extract is a serious issue in the bee products market. The aim of this study was to identify marker compounds in adulterated propolis, and examine the transformation of chemical components from poplar buds to propolis. The chemical profiles of poplar extracts and propolis were compared, and a new marker compound, catechol, was isolated and identified from the extracts of poplar buds. The polyphenol oxidase, catechol oxidase, responsible for catalyzing oxidation of catechol was detected in poplar buds and propolis. The results indicate catechol can be used as a marker to detect propolis adulterated with poplar extract.