Current Bioactive Compounds - Volume 12, Issue 1, 2016

This review is a brief but comprehensive overview on the multi-target profile of oleocanthal, an extra-virgin olive oil (EVOO) phenol corresponding to the (-)-decarboxymethylligstroside aglycone, speculating about its potential in the prevention and/or treatment of various diseases, such as neurodegeneration, inflammation and cancer.

The effect of a prickly pear peel extract on cholesterol excretion and plasma and hepatic cholesterol levels in hamsters with induced hypercholesterolemia was investigated. Female and male hamsters were fed for 5 weeks with experimental diets: NC, normal cholesterol diet; HC, hypocholesterolemic diet; HCOp, HC with prickly pear peel extract and HCPh, HC with phytosterols. Male and females hamsters fed HCOp diet increased their neutral fecal sterols (cholesterol + coprastanol) excretion by 77% (p<0.042) and 120% (p<0.003), respectively, compared to counterparts fed HC diet. Plasma total cholesterol was significantly reduced only in male hamsters fed HCPh. The phytosterols content in HCOp diet was almost 5 fold less compared to HCPh, and both treatments have reduced 35% (p<0.0001) hepatic cholesterol compared to hamsters fed the HC diet. Thus, the prickly pear peel extract rich in phytosterols showed a hypocholesterolemic effect. This evidence suggests that the prickly pear byproduct tested herein has potential to be employed as ingredient or supplement to lower cholesterol and prevent cardiovascular diseases.

Chemical stability of anthocyanins in aqueous solutions has been one of the major drawbacks for health applications. Complexation of anthocyanins formed by aqueous extracts of dried cobs of Zea mays L. ceritina Kulesh. (CC) and blue petals of Clitoria ternatea L. (CT) was challenged by thermal accelerated stability testing of total anthocyanins by pH differential method, with in vitro antiinflammatory and anti-candida screening tests. Decomposition of total anthocyanins of the anthocyanin complex (AC), CC and CT in aqueous conditions follows first-order kinetic with derived activation energies of 53.3, 18.0, 34.4 kJ/mol, respectively, indicating higher thermal tolerance by complexation. AC, at concentrations up to 2.5 mg/mL, was not cytotoxic to the exposed human gingival epithelial cells (HGEPp0.5). At 0.1 μg/mL, AC recovers cellular proteins and nucleic acids of TNF-alpha induced inflamed HGEPp0.5 cells, detected by FTIR spectroscopy and principle component analysis (PCA). Anti-candida activity of AC was determined at 80 and 160 μg/mL as the minimum inhibitory and minimum fungicidal concentrations, respectively. It is concluded that complexation improved chemical stability with anti-inflammatory and anti-candida activities of the anthocyanins in an oral epithelial cell line.

Objective: The current study was planned to analyze the effects of the aqueous extract of Cynodon dactylon (AECD) in a rat model of Streptozotocin (STZ) induced-diabetes and nitric oxide (NO)-deficient hypertension. Materials and Methods: Diabetes was induced by a single dose of STZ (55 mg/kg, i.p., in 0.1M citrate buffer, pH 4.5). To induce the NO-deficient hypertension, rats were treated with the Nitric Oxide synthase inhibitor- NG-nitro-l-arginine methyl ester; L-NAME (0.5 mg/ml), p.o. for 4 weeks. The effects observed after 28 days treatment with aq. extract of Cynodon dactylon 200 mg kg per day were evaluated in diabetic–hypertensive rats. In all groups, body weight of animals was measured weekly throughout the study (28 days). Blood glucose level and total cholesterol level were measured at day 0 after induction of diabetes and at day 28. Arterial blood pressure of all the groups were measured at day 14 and day 28 by tail cuff method. At the end of experiment, Serum glutamic oxaloacetic transaminase (SGOT) level in all groups was measured. Results: A decrease in body weight was observed in the case of STZ diabetic, L-NAME and D+L-NAME control groups whereas no loss in the weight of animal was observed in the group treated with the aqueous extract of C. dactylon. The study showed that a) aqueous leaf extract of Cynodon dactylon prevented attenuation of the blood glucose and total cholesterol in all the groups; b) significant decrease in Mean Arterial Blood Pressure (MABP) and c) decrease in SGOT level. Conclusion: The traditional use of Cynodon dactylon for the treatment of diabetes and arterial hypertension is supported by the findings of present study, and indicate that it may have a beneficial effect in patients with co-existing diabetic hypertension.

Medicinal plants are rich sources for drug discovery. Occurrence of Diabetes mellitus is increasing because of changes in human lifestyle. So, design or discovery of new and more effective and safer drugs is needed. At the present study, the enzyme inhibitory effects of methanol extracts of selected Lamiaceae species (Salvia syriaca L., Teucrium polium L., Phlomis olivieri Benth., Nepeta ispahanica Boiss., Scutellaria tomentosa Benth., Salvia limbata C.A. Mey., Teucrium orientale L., Salvia atropatana Bunge., Salvia nemorosa, Salvia multicaulis Vahl., Ajuga chamaecistus Ging. ex Benth., Mentha longifolia L. and Satureja khuzestanica) were evaluated. The enzyme inhibitory activities were tested against α-amylase and α-glucosidase, which are linked to diabetes. Also, brine shrimp lethality assay was used to determine the cytotoxicity of the extracts. All methanol extracts showed moderate to high inhibitory effects on the tested enzymes. Scutellaria tomentosa and Mentha longifolia exhibited the strongest α-amylase and α-glucosidase inhibitory effects, respectively. These activities were ranged from 0.135 to 0.291 mmol in α-amylase assay and 1.256 to 6.640 mmol acarbose equivalents/g extract in α-glucosidase assay. The highest cytotoxic effect was observed for the extract of S. syriaca roots (LC50 = 12.3 μg/ml). The results suggest that these Lamiaceae species could be considered as a source of natural agents for the preparing of new pharmaceuticals and functional foods especially for the management of Diabetes mellitus.

This paper describes a study of the content of total phenolic contents, the antioxidant capacity and the cyclic voltammetry of Zilla macroptera aqueous extract. The results demonstrate that the content of total phenolics was 89±2.46 μg of Gallic acid equivalence per 1 mg of extract and the content of total flavonoids was 12.99±0.67 μg of Quercetin equivalency per 1 mg of extract. Four methods ‘‘in vitro’’ were used to evaluate the antioxidant capacity of Zilla macroptera aqueous extract. The reducing power test showed that the sample has an equivalent activity of 63.16±1.09 μg of Ascorbic acid for 1 mg of extract. The total antioxidant capacity presented an equivalent capacity of 25±0.94 μg of Ascorbic acid per 1 mg of extract. The voltammogram indicates two potentials oxidation peaks; 0.6 V and 0.92 V towards the reference electrode (Ag /AgCl).

Background: Andrographolide, a labdone diterpene extracted from Andrographis paniculata possesses various medicinal properties and has been used in treatment of number of chronic diseases, in humans. Objectives: Evaluation of the effects of andrographolide on COX-2 enzyme (in silico and in vitro studies). Materials and Methods: The interactions of andrographolide with COX-2 protein were evaluated (in silico) by molecular docking using Auto Dock Vina, version 4.0 software and visualized using pyMOL. An isocratic based HPLC method was developed for characterization of the purified andrographolide using mobile phase [methanol: water: acetonitrile (65:10:25)] and its UV absorption at different wavelengths. This compound was further tested in vitro against human recombinant COX-2 enzyme for its effect at various concentrations (10, 25, 50, 75, 100, 150, 200 nM). Celecoxib was used as a reference standard for comparison in both studies. Results: The in silico studies revealed that andrographolide exhibited higher binding score of -10.3 K cal/mol and formation of hydrogen bonds with His 90 and Arg 120 amino acid residues of COX-2 indicating its binding to the protein. A relatively rapid, accurate and precise HPLC method was developed for andrographolide with the retention time of 3.255 min. The in vitro studies revealed a concentration dependent inhibitory effect of andrographolide on the COX-2 activity with an IC50 value of 50 nM. Conclusion: Our studies confirmed the inhibitory effects of andrographolide on COX-2 enzyme (in silico and in vitro), as the basis for its anti-inflammatory potentials.

This study investigates the chemical composition and the biological activities of the essential oils of Vitex agnus-castus. The essential oils from the dry leaves, flowers and seeds of Vitex agnus- castus L., were obtained by hydro-distillation, and their volatile constituents were identified by GC/MS. Antioxidant activity of the samples was determined by DPPH method. Antifungal and antibacterial activities were tested using three fungal strains by reported method and eight bacterial strains by well-diffusion method. The major components in the oil of flowers were 1,8-cineole (17.16%), caryophyllene (12.94%) and terpinen-4- ol (10.22%), while the dominant compounds in the oil of the seeds were 1,8-cineole (14.92%), cedrelanol (13.95%) and 7a-isopropenyl-4,5-dimethyloctahydroindene-4-carboxylic acid (13.90%). The oil of leaves contained an abundance of1,8-cineole (18.27%), as well. Their compositions were compared with oils from the plants obtained from Europe, America and Asia. The essential oils of seeds and leaves showed antibacterial potency against Klebsiella pneumonea, E. coli, and Pseudomonas aeruginosa, respectively. While the oil of leaves and flowers showed a high antifungal activity against Penicillium escpansum, Aspergillus flavus dominant compounds, respectively.