Camilia G. Michel

Anti-diabetic activity and stability study of the formulated leaf extract of Zizyphus spina-christi (L.) Willd with the influence of seasonal variation

AIM OF THE STUDY The present study aimed to evaluate the anti-diabetic activity of Zizyphus spina-christi leaf extract (200 mg/kg b.w.), plain and formulated in STZ-diabetic rats. Percentage yield of extracts, marker yield (christinin-A) and antihyperglycemic potencies, depending on seasonal variation were investigated. The chemical stability, study of storage conditions, shelf life T90 prediction of both plain extract and formulated soft gelatin capsules by accelerated studies were studied. MATERIAL AND METHODS Changes in all studied parameters after oral administration of Z. spina-christi extract for 28 days were reported. Seasonal variation affecting yield and activities was studied. Flavonoid contents were HPLC evaluated. The capsules were stored at 30, 40 and 50°C [75% relative humidity] and their residual christinin-A content was assayed for 24 weeks. Christinin-A chemical degradation was monitored by HPLC stability indicating method previously validated. Possible physical examination was checked by dissolution test of the content of the capsules using dissolution tester USP XXIV. RESULT Oral administration of Z. spina-christi leaf extract, plain and formulated for 28 days reduced blood glucose level with significant increase in serum insulin and C-peptide levels. Marked elevation in total antioxidant capacity with normalization of percentage of glycated hemoglobin (HbA1C%) was reported. Moreover, they succeeded to reduce the elevated blood lactate level and to elevate the reduced blood pyruvate content of diabetic rats. In line with amelioration of the diabetic state, Zizyphus extract, plain and formulated restored liver and muscle glycogen content together with significant decrease of hepatic glucose-6-phosphatase and increase in glucose-6-phosphate dehydrogenase activities. In vitro experiments showed a dose-dependent inhibitory activity of Zizyphus extract against α-amylase enzyme with (IC(50)) at 0.3 mg/ml. Such finding has been supported by the in vivo suppression of starch digestion and absorption by Zizyphus extract in normal rats. The flavonoids content of the formulated leaves (collected during June 2009) were found to be 11.5 μg/g of the dry plant material (expressed as quercetin) and 58.8 μg/g of the dry plant material (expressed as rutin). The shelf life for the capsules stored at 30, 40 and 50°C [75% relative humidity] for plain and formulated extract were calculated to be 66.90 and 70.74 weeks, respectively. CONCLUSION The current work revealed that Z. spina-christi leaf extract, plain and formulated, improved glucose utilization in diabetic rats by increasing insulin secretion which may be due to both saponin and polyphenols content and controlling hyperglycemia through attenuation of meal-derived glucose absorption that might be attributed to the total polyphenols. Studies showed that leaves are preferably collected from June to October. Finally, the release followed the Higuchi kinetic model, indicating diffusion dominated drug release with no drop in the dissolution values throughout the test period.

Comparative metabolite profiling and fingerprinting of genus Passiflora leaves using a multiplex approach of UPLC-MS and NMR analyzed by chemometric tools

AbstractPassiflora incarnata as well as some other Passiflora species are reported to possess anxiolytic and sedative activity and to treat various CNS disorders. The medicinal use of only a few Passiflora species has been scientifically verified. There are over 400 species in the Passiflora genus worldwide, most of which have been little characterized in terms of phytochemical or pharmacological properties. Herein, large-scale multi-targeted metabolic profiling and fingerprinting techniques were utilized to help gain a broader insight into Passiflora species leaves’ chemical composition. Nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) spectra of extracted components derived from 17 Passiflora accessions and from different geographical origins were analyzed using multivariate data analyses. A total of 78 metabolites were tentatively identified, that is, 20 C-flavonoids, 8 O-flavonoids, 21 C, O-flavonoids, 2 cyanogenic glycosides, and 23 fatty acid conjugates, of which several flavonoid conjugates are for the first time to be reported in Passiflora spp. To the best of our knowledge, this study provides the most complete map for secondary metabolite distribution within that genus. Major signals in 1H-NMR and MS spectra contributing to species discrimination were assigned to those of C-flavonoids including isovitexin-2″-O-xyloside, luteolin-C-deoxyhexoside-O-hexoside, schaftoside, isovitexin, and isoorientin. P. incarnata was found most enriched in C-flavonoids, justifying its use as an official drug within that genus. Compared to NMR, LC-MS was found more effective in sample classification based on genetic and/ or geographical origin as revealed from derived multivariate data analyses. Novel insight on metabolite candidates to mediate for Passiflora CNS sedative effects is also presented. Graphical AbstractA comparative NMR and MS spectra of extracted components derived from 17 Passiflora accessions to be analyzed using multivariate data analyses for species classification.

Phytochemical and biological investigation of the extracts of Nigella sativa L. seed waste.

Different extracts of Nigella sativa L. seed waste; aqueous (AE) 200 mg/kg, ethanol 70% (EE) 250 mg/kg and hexane (HE) 10 mg/kg, were evaluated for their hepatoprotective activities. They were administered orally, once daily, for 5 consecutive days. On day 5, liver injury was induced in animals by a single i.p. injection of carbon tetrachloride (10 mg/kg b. w. of 0.25% (v/v). Hepatoxicity produced, was evaluated by both biochemical and histopathological investigations. The aqueous extract attenuated the CCl(4) -induced liver damage likely due to the decrease of proinflammatory cytokines and T-cell proliferation. This was noticed by a significant decrease in both serum and tissue cytokines; tumor necrosis factor-alpha (TNF-α), interferon-gamma (INF-γ) and interlukin-beta (IL-1β), in the markers of liver functions; bilirubin and glutamic pyruvic transaminase (GPT) and in the oxidative stress markers; malondialdehyde (MDA) and glutathione content (GSH). Fractionation of this extract was performed and its component, protein, saponin, and polyphenol fractions were evaluated by appropriate analytical procedures. The crude protein of the seed waste reached 36.85% while protein fingerprint showed four bands ranging from 91.97 KD and 29.00 KD. The saponin content was evaluated through the determination of the haemolytic index and reached 15.56 mg/g dry powder. Finally, Folin Ciocalteu method was used for the determination of the total polyphenols. The same biochemical and histopathological studies were again performed on the different fractions of the aqueous extract; protein fraction (PF) 10 mg/kg, saponin fraction (SF) 5 mg/kg and polyphenol fraction (FF) 10 mg/kg. The biochemical changes were improved only by the protein fraction (PF) of the seed waste of Nigella sativa. This was manifested by a significant reduction in both serum and tissue cytokines in the liver markers and in the oxidative stress markers. Moreover, liver histopathology showed that (PF) reduced the incidence of liver lesions including hepatic cells cloudy swelling, lymphocytes infiltration, hepatic necrosis and fibrous connective tissue proliferation induced by CCl(4) in mice. From this study, it is concluded that the protein fraction of the aqueous extract of Nigella sativa seed waste exhibited a promising hepatoprotective effect in the management of different liver disorders.

Bioactive terpenoids from the Red Sea soft coral Sinularia polydactyla

Chemical investigation of an ethyl acetate soluble fraction of Sinularia polydactyla (Ehrenberg) led to the isolation of three known terpenoides, two of them sterols, 24-methylcholestane-3β,5α,6β,25-tetrol 25-monoacetate (1), 24-methylcholestane-5-en-3β,25-diol (2), in addition to a cembranoid diterpene, durumolide C (3), for the first time. The cytotoxicity and antimicrobial activities of the ethyl acetate extract and the isolated compounds 1–3 were evaluated in vitro. Durumolide C (3) showed selective cytotoxicity against HepG2 (IC50 1.0 μg/mL), whereas 24-methylcholestane-3β,5α,6β,25-tetrol 25-monoacetate (1) showed IC50 of 6.1 and 8.2 μg/mL against Hep2 and HCT human cancer cell lines, respectively.