Search

Two new compounds, 11S-methoxy-11,12-dihydro phytuberin (2) and 9S-methoxy-benzocyclononan-7-one (6), together with twenty-six known ones were isolated from Lycium schweinfurthii (Solanaceae). Thei...

A new glucoside, 3-methoxy-4-O-β-D-glucopyranosyl-methyl benzoate, has been isolated from Lycium schweinfurthii along with five known compounds through bioactivity guided fractionation of the total plant methanolic extract towards α-glucosidase inhibitory activity. All the isolated compounds were tested for their inhibitory effect on α-glucosidase enzyme. As a result, four of them showed a potent inhibitory activity and thus constitute a therapeutic approach to decrease postprandial hyperglycemia in diabetic patients.

A method has been developed for the quantitative elemental analysis of Mentha longifolia L. leaves collected from different cities in Saudi Arabia using total reflection X-ray fluorescence. Using a microwave digestion system, 100 mg of each sample was completely digested using 3 mL of nitric acid and 2 mL of hydrogen peroxide. The stabilization of the digested samples on the silicon reflectors was studied using a silicone solution and polyvinyl alcohol. 5 µL of either silicone solution or polyvinyl alcohol (1% m/v) was pipetted and dried on the silicon reflector prior to the deposition of the digested samples. It was recognized that there is some enhancement on the intensity of the peak area with the silicone solution at photon energies less than 11 keV. However, the obtained results confirm the ability of using silicone solution or polyvinyl alcohol (1% m/v) as the stabilizer prior to the deposition of the sample droplet on the quartz reflector. However, the silicone solution was more applicable....

Climatic and geographic conditions play an important role in the variations of chemical composition of essential oils and consequently its biological activities. The chemical constituents of essential oil from leaves of S. molle L. (Family Anacardiaceae) growing in Taif, KSA were investigated using capillary GC-MS technique. Mono- and sesquiterpenes represented by fifty compounds were identified and quantified. The total sesquiterpenes had the higher quantity (594.50 mg/100 g FWL) whereas the total monoterpenes had a lower quantity (353.69 mg/100 g FWL). α-phellandrene (211.70 mg/100 g FWL, 22.33%) was the major compound in the monoterpenes whereas δ-cadinene (57.72 mg/100 g FWL) and guaiol (55.69 mg/100 g FWL) were the major compounds in the sesquiterpenes. The special climate and geographic location of Taif governorate play an important role in the variation of chemical composition of S. molle essential oil. The S. molle essential oil showed promising anticancer activity toward the HepG2 cell li...

Rosa damascena Miller var. trigintipetala Dieck (Taif rose) is considered as one of the most important economic products of Taif governorate, KSA. In this study, the different components of Taif rose essential oil were characterized using GC-MS technique. In addition, the in vitro cytotoxic, genotoxic and anticancer effects of the oil were investigated toward normal human peripheral blood lymphocytes and two kinds of human cancer cell lines; HepG2 and MCF7. GC-MS analysis showed that the acyclic monoterpene alcohols had the highest content (254.7 mg/g oil). The major components of the oil that have relative percentage > 5% were β-citronellol, geraniol, nerol, linalool, phenylethyl alcohol and nonadecane. The results showed that the oil was safe at a dose < 50 μg/mL when applied to normal human blood lymphocytes monitored by 7-AAD assay and DNA index determination. The oil exerted anticancer activity against HepG2 and MCF7 with IC50 = 13.03 ± 0.8 and 16.44 ± 1.4 μg/mL respectively. In conclusion, t...

It is known that hypertension among blacks starts at earlier ages and has a higher mortality rate as compared to other populations. Alpha-2 receptors were compared in the platelets of normotensive (n=19) and hypertensive pregnant black women (n=29). Characterization and identification of alpha-2 receptors were performed by radio receptor assay. Platelet membranes were incubated with various concentrations of [3H]yohimbine as an alpha-2 antagonist. The maximum number of binding sites (Bmax) and dissociation constant (Kd) were determined by Scatchard analysis. The maximum number of binding sites were 331 fM/mg (normotensive n=19), 286 fM/mg (chronic hypertension n=12), and 357 fM/mg (preeclampsia n=17). These values were not statistically significant. Conclusions: alpha-2 platelet receptors are not altered in hypertensive pregnancies.