Antihyperlipidemic, Antihyperglycemic, and Liver Function Protection of Olea europaea var. Meski Stone and Seed Extracts: LC-ESI-HRMS-Based Composition Analysis.

Methanol and methanol/water extracts of olive stones and seeds from Olea europaea var. meski were analyzed by reversed-phase high-performance liquid chromatography (HPLC) with diode array detection and mass spectrometry (LC-MS/MS). A total of 28 metabolites were identified; among them are hydroxycinnamic acid derivatives, phenolic alcohols, flavonoids and flavonoid glucosides, secoiridoids, and terpenes. All the extracts were screened for the inhibitory effect of key enzymes related to diabetes and obesity, such as α-amylase and lipase. An in vitro study revealed that Olea meski stone ethanol (MSE) and methanol (MSM) extracts and Olea meski seed ethanol (MSE1) and methanol (MSM1) extracts exert an inhibitory action against lipase and α-amylase. The most potent activity was observed in the StM extract with IC50 equal to 0.19 mg/ml against DPPH oxidation, 1.04 mg/ml against α-amylase, and 2.13 mg/ml against lipase. In HFFD rats, the findings indicated that the increase of body weight, LDL, TC, and glucose levels and then the decrease in HDL-C were significantly suppressed in the MSM-treated group than those in HFFD rats. Moreover, the MSM extract exhibited a prominent selective inhibitory effect against intestinal lipase and α-amylase activities. The MSM extract was also able to protect the liver-kidney functions efficiently, which was evidenced by biochemicals and histological studies.

Anti-diabetic and lipid-lowering effects of drimane sesquiterpenoids isolated from Zygogynum pancheri.

Recently, it has been shown that drimane-type sesquiterpenoids isolated from Zygogynum pancheri, a species native to New Caledonia, possessed significant α-amylase inhibitory activities. To further explore their antidiabetic potential, we investigated the effect of 1ß-O-(E-cinnamoyl)-6α-hydroxy-9epi-polygodial (D) and 1ß-E-O-p-methoxycinnamoyl-bemadienolide (L), two of the most active compounds of the series, on diabetic model rats. Compounds D and L (2 mg kg/day) were daily and orally administrated for 30 days to streptozotocin (STZ) (150 mg/kg) induced male diabetic Wistar rats. Animals were allocated into five groups of six rats. Comparatively to diabetic rats, treatments with D and L compounds were able to significantly (P < 0.05) decrease Fasting Blood Glucose (FBG) (70.15%, 71.02%), serum total cholesterol (46.27% and 39.38%), triglycerides (56.60% and 58.15%), creatinine (37.31% and 36.49%) and uric acid levels (67.76% and 69.68%), respectively. Compounds D and L also restored the altered plasma enzyme (aspartate aminotransferase, AST (47.83% and 43.20%), alanine aminotransferase, ALT (49.76% and 48.35%, alkaline phosphatase, ALP (72.78% and 73.21%)) and lactate dehydrogenase, LDH (47.95% and 53.93%) levels to near normal, respectively. Administration of Glymepiride, significantly (p < 0.05) reduced FBG (73.94%) in STZ induced diabetic rats. Additionally, the compounds D and L exhibited inhibitory effects in vivo on lipase activity of diabetic rats (54.83% and 52.25%), respectively. The outcomes of this study suggested that these two drimanes could be considered as efficient hypoglycemic, hypolipidemic and antiobesity agents for diabetes management and its complications.

Modulatory Effect of an Isolated Triglyceride from Fenugreek Seed Oil on of α-Amylase, Lipase and ACE Activities, Liver-Kidney Functions and Metabolic Disorders of Diabetic Rats.

This study was designed to examine physicochemical characteristics, chemical compositions and biological activities of fenugreek seed oil (FSO) and its pure triglyceride (TG). One fenugreek TG was purified using a bioassay-guided fractionation and administrated to surviving diabetic rats. The free fatty acids percentage as well as, the peroxide, the saponification and the iodine values were 2%, 12 mequiv. O2/kg of oil, 189 (mg KOH/g) and 110 (g/100 g of oil), respectively. Linolenic acid (C18:3 26.14%), Linoleic acid (C18:2 41.13%) and Oleic acid (C18:1 17.07%) were the dominant fatty acids in the FSO. ß-sitosterol was the major sterol (85.3%) in the FSO. LnLnO (17.1%), LLL (16.6%), OLL and OOLn (8.4%), were the abundant triglycerides. The hexane extract of fenugreek seed (exhibiting the powerful inhibitory activity against alpha-amylase) was purified using a bioassay-guided fractionation affording one fenugreek TG: (11Z)-11- eicosenoic acid 2, 3- bis[((9Z, 12Z, 15Z)-1-oxo-9, 12, 15-octadecatrien-1-yl)oxy] propyl ester. In diabetic rats, the administration of the fenugreek TG inhibited α-amylase activity in small intestine by 36% as compared to untreated diabetic rats. Moreover, fenugreek TG increased insulin sensibility which leads to decrease in blood glucose level by 43%. In addition, this study demonstrated that administration of pure fenugreek TG to diabetic rats ameliorated the glycogen rate in liver and muscle. In addition, the administration of fenugreek TG reverted back the activity of angiotensin converting enzyme respectively in kidney and plasma by 33 and 29%. Interestingly, the fenugreek TG inhibited lipase activity in small intestine by 33% which leads to the regulation of lipid profile. Moreover, the fenugreek TG protected liver-kidney function evidenced by histological study. In conclusion, our finding demonstrates that the administration of fenugreek TG to diabetic rats can make it a potential candidate for industrial application as a pharmacological agent for the treatment of hyperglycemia.

LC-MS-MS and GC-MS analyses of biologically active extracts and fractions from Tunisian Juniperus phoenice leaves.

CONTEXT: Despite some studies related to Juniperus phoenicea L. (Cupressaceae), phytochemical and biological investigations of this plant remain unexplored. OBJECTIVE: This work is the first report dealing with the identification and characterization of volatile components and flavonoids in hexane and methanol extracts from J. phoenicea leaves Materials and methods: Antioxidant activity of hexane, and methanol extracts from J. phoenicea leaves were determined by DPPH-radical scavenging assay. α-Amylase inhibitory activity was evaluated by enzyme inhibition using in vitro assay (each extract was dissolved in DMSO to give concentrations of 50, 100 and 200 mg/mL). The chemical composition of fractions (Fr1-Fr3) from methanol extract was determined by high-performance liquid chromatography coupled with mass spectroscopy (HPLC-MS) analysis. RESULTS AND DISCUSSION: The hexane extract was analyzed by GC-MS technique which allowed the identification of 32 compounds. The main constituents were α-humulene (16.9%), pentadecane (10.2%) and α-cubebene (9.7%). Fraction Fr 2 exhibited a strong DPPH radical-scavenging activity (IC50 = 20.1 µg/mL) compared to that of BHT as well as the highest α-amylase inhibitory activity (IC50 = 28.4 µg/mL). Three flavonoids were identified in these fractions using HPLC-MS analysis: Quercetin 3-O-glucoside, isoscutellarein 7-O-pentoside and quercetin 3-O-pentoside. In addition, the more active fraction (Fr 2) was purified with semi-preparative HPLC affording one pure compound (amentoflavone) using 1H NMR analysis. This compound exhibited powerful DPPH radical-scavenging (IC50 = 14.1 µg/mL) and α-amylase inhibition (IC50 = 20.4 µg/mL) effects. CONCLUSION: This study provides scientific support to some medicinal uses of J. phoenicea found in North Africa.

Inhibitory potential of omega-3 fatty and fenugreek essential oil on key enzymes of carbohydrate-digestion and hypertension in diabetes rats.

BACKGROUND: diabetes is a serious health problem and a source of risk for numerous severe complications such as obesity and hypertension. Treatment of diabetes and its related diseases can be achieved by inhibiting key digestives enzymes-related to starch digestion secreted by pancreas. METHODS: The formulation omega-3 with fenugreek terpenenes was administrated to surviving diabetic rats. The inhibitory effects of this oil on rat pancreas α-amylase and maltase and plasma angiotensin-converting enzyme (ACE) were determined. RESULTS: the findings revealed that administration of formulation omega-3 with fenugreek terpenenes (Om3/terp) considerably inhibited key enzymes-related to diabetes such as α-amylase activity by 46 and 52% and maltase activity by 37 and 35% respectively in pancreas and plasma. Moreover, the findings revealed that this supplement helped protect the ß-Cells of the rats from death and damage. Interestingly, the formulation Om3/terp modulated key enzyme related to hypertension such as ACE by 37% in plasma and kidney. Moreover administration of fenugreek essential oil to surviving diabetic rats improved starch and glucose oral tolerance additively. Furthermore, the Om3/terp also decreased significantly the glucose, triglyceride (TG) and total-cholesterol (TC) and LDL-cholesterol (LDL-C) rates in the plasma and liver of diabetic rats and increased the HDL-Cholesterol (HDL-Ch) level, which helped maintain the homeostasis of blood lipid. CONCLUSION: overall, the findings of the current study indicate that this formulation Om3/terp exhibit attractive properties and can, therefore, be considered for future application in the development of anti-diabetic, anti-hypertensive and hypolipidemic foods.