Phytochemical investigation of Rhus tripartita and its activity against cyclooxygenases and acetylcholinesterase

Purpose: To investigate the inhibitory activity of crude methanol extract, fractions and two pure compounds from Rhus tripartita stem cyclooxygenases (COX-1 and COX-2) and acetylcholinesterase (AChE); also, to evaluate their antioxidant properties in in-vitro assays.Methods: R. tripartita extract and fractions were examined as inhibitors of COX-1 and COX-2 and AChE. Their antioxidant properties were also evaluated using various antioxidant tests, including free radical scavenging, nitric oxide, and total antioxidant capacity.Results: Ethyl acetate fraction (RT2), aqueous fraction (RT4), subfraction RT2-II, and subfraction RT2-III had a potent inhibitory effect on AChE with low IC50 values. At the same time, a subfraction (RT2-III) was an effective COX-2 inhibitor (94.5 % at 10 μg/mL) followed by ethyl acetate fraction (RT2; 79.39 %), aqueous fraction (RT4; 70 %), total extract (RT; 66.18 %), subfraction RT2-III (64.08 %), compound 5 (epicatechin; 61.25 %), compound 2 (taxifolin; 55.63 %), subfraction RT2-II (46.85 %), and butanol fraction (RT3; 40.80%). RT2, RT4, RT2-II, RT2-III, and compound 2 each showed 100 % inhibition at 20 μg/mL.Conclusion: The ethyl acetate fraction (RT2), aqueous fraction (RT4) and subfractions RT2-II and RT2- III are effective natural inhibitors of AChE. Subfraction RT2-III is the best COX-2 inhibitor, followed by ethyl acetate fraction RT2 and aqueous fraction (RT4). These bioactive materials can be considered natural COX-2 and AChE inhibitorsKeywords: Cyclooxygenase, Anti-nflammatory, Acetylcholinesterase, Anacardiaceous, Taxifolin, Epicatechi

Antimicrobial activities of some Saudi Arabian herbal plants

Background: Several edible plants are used in Kingdom of Saudi Arabia since early time to control microbial infections. In the present study, twenty-four Saudi Arabian medicinal plants d according to traditionally used were select and investigated for the antimicrobial activitiesMaterials and Methods: This study was designed at evaluating the antimicrobial activities of the methanol extracts of twenty-four species of sixteen plant families used in the traditional medicine by Saudi Arabian people for the treatment of numerous ailments of the microbial and non-microbial origin against four Gram-positive, four Gram-negative bacteria and four fungi and yeast using the agar well diffusion method.Results: Of most of the plants tested were found to be active against two to eight organisms. Five plants were active against eight organisms. The data appeared that extracts of Echium arabicum (SY-176), Rhantarium epapposum (SY-180), Rumex vesicarus (SY-181), Ziziphus nummularia (SY-188), Caylusea hexagyna (SY-197) and Artemisia monosperma (SY-198) have anti-microbial activity against the most of tested bacteria, fungi and yeast. Whereas (SY-181), the extracts of Teucrium oliverianum (SY-175), Zilla spinosa (SY-187), and Rhazya stricta (SY-195) have poor action against the tested bacteria, fungi and yeast.Conclusion: The antimicrobial activity of plant extracts against bacteria was more effective than against fungiKeywords: Gram-positive bacteria, Gram-negative bacteria, fungi, yeast, medicinal plants, Saudi Arabi

ACETYLCHOLINESTERASE INHIBITION AND ANTIOXIDANT ACTIVITY OF SOME MEDICINAL PLANTS FOR TREATING NEURO DEGENARATIVE DISEASE

Background: Numerous plants in traditional practices of medicine have been used to treat cognitive disorders, including neurodegenerative diseases such as Alzheimer’s disease (AD) and other memory related disorders. Materials and Methods: We present here the evaluation of acetylcholinesterase (AChE) inhibitory and antioxidant activities of the aqueous methanol extracts of five traditional medicinal plants. Citrullus colocynthis, Emex spinosa, Rhazya stricta, Scrophularia hypericifolia and Caylusea hexagyna extracts were tested for their acetylcholinesterase inhibitory effect ant their antioxidant effect at different concentrations. Results: Citrullus colocynthis and Emex spinosa inhibited acetylthiocholinesterase at 400 µg/ ml by 83.54 and 81.92%. Emex spinosa and Scrophularia hypericifolia produced the maximum effect as DPPH radical scavenger (IC50= 10.89 and 11.88µg/ ml, respectively). Scrophularia hypericifolia showed the highest effect as superoxide radical scavenger (IC50= 20.83 µg/ ml)also it produced the highest ability to scavenge hydrogenperoxide radicals (IC50= 8.66 µg/ ml) while Emex spinosa and Caylusea hexagyna showed least IC50 for ferrous ion chelation (IC50≈15 µg/ ml) with powerful reduction capability. Conclusion:The determined antioxidant properties magnified the total antioxidant effect determined by ABTS assay that completely inhibited lipidperoxidation at 200 µg/ ml

Novel ethyl 1,5-disubstituted-1H-pyrazole-3-carboxylates as a new class of antimicrobial agents

A series of pyrazole derivatives 9-22 were designed and synthesized. All the newly synthesized compounds were assayed for their antimicrobial activity against the Gram-positive bacteria Staphyllococcus aureus and Bacillius subtilis and the Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, in addition to the fungi organisms, Candida albicans, C. parapsilosis and C. tropicalis. Ethyl 5-(2,5-dimethylthiophen-3-yl)-1-phenyl-1H-pyrazole-3-carboxylate (21) (MICE.coli =0.038 µmol mL–1, MICP. aerug = 0.067 µmol mL–1) is nearly as active as ampicillin (MIC = 0.033 and 0.067 µmol mL–1, respectively). Ethyl 5-(4-bromo-2-chlorophenyl)-1-phenyl-1H-pyrazole-3-carboxylate (16) (MIC = 0.015 µmol mL–1) is more active than fluconazole (0.020 µmol mL–1) as a reference drug against C. parapsilosis

Biochemical and histological evidences for the antitumor potential of Teucrium Oliverianum and Rhazya stricta in chemically-induced hepatocellular carcinoma

Background: Teucrium oliverianum and Rhazya stricta are medicinal plants used in traditional and herbal medicine for the treatment of diabetes, liver diseases and inflammatory conditions. The present study was planned to investigate the antitumor efficacy of Teucrium oliverianum and Rhazya stricta in chemically-induced hepatocellular carcinoma (HCC) in rats.Materials and Methods: Forty adult male rats weighing 170-200 g were divided into four groups; each group was comprised of ten rats: (1): Normal healthy animals served as negative control group, (2):  Hepatocellular carcinoma (HCC) group in which the rats were orally administered Nnitrosodiethylamine (dissolved in 0.9% normal saline), in a dose of 20 mg/kg b.wt. five times a week for six weeks, (3): HCC group treated with Teucrium oliverianum extract in a dose of 600 mg/kg b.wt for two months and (4): HCC group treated with Rhazya stricta extract in a dose of 750 mg/kg b.wt for two months. Serum alanine  aminotransferase (ALT), asparatate aminotransferase (AST), alkaline phosphatase (ALP) and  gammaglutamyl transferase (γ-GT) activities were estimated. Serum  carcinoembyronic antigen (CEA), alpha-fetoprotein (AFP), alpha-L-fucosidase (AFU), glypican-3 (GPC-3), golgi protein 73 (Gp-73) and vascular endothelial growth factor (VEGF) levels were determined. Histopathological examination of liver tissue sections was also carried out.Results: The HCC group showed significant elevation in serum AST, ALT, ALP and γ-GT activities as well  as CEA, AFP, AFU, Gpc-3, Gp 73 and VEGF levels versus the negative control group. Photomicrograph of liver tissue sections of rats in HCC revealed hepatic parenchyma with foci of anaplastic hepatocellular carcinoma as well as other foci of cystic cholangio carcinoma associated with areas of telangictasis with haemorrhage as well as individual hepatocellular necrosis.Conclusion: Treatment of HCC groups with Teucrium oliverianum or Rhazya stricta extract experienced significant improvement in the measured biochemical parameters as well as in the structural  organization of the liver. In conclusion, the current study provided experimental evidences for the antitumor efficacy of Teucrium oliverianum and Rhazya stricta against hepatocellular carcinoma. Such effect could be attributed to hepatoprotective properties, antiproliferative activity and antiangiogenic potential.Keywords: Hepatocellular carcinoma, Teucrium oliverianum, Rhazya stricta, rat

ANTIMICROBIAL ACTIVITIES OF SOME SAUDI ARABIAN HERBAL PLANTS

Background: Several edible plants are used in Kingdom of Saudi Arabia since early time to control microbial infections. In the present study, twenty-four Saudi Arabian medicinal plants d according to traditionally used were select and investigated for the antimicrobial activities Materials and Methods: This study was designed at evaluating the antimicrobial activities of the methanol extracts of twenty-four species of sixteen plant families used in the traditional medicine by Saudi Arabian people for the treatment of numerous ailments of the microbial and non-microbial origin against four Gram-positive, four Gram-negative bacteria and four fungi and yeast using the agar well diffusion method. Results: Of most of the plants tested were found to be active against two to eight organisms. Five plants were active against eight organisms. The data appeared that extracts of Echium arabicum (SY-176), Rhantarium epapposum (SY- 180), Rumex vesicarus (SY-181), Ziziphus nummularia (SY-188), Caylusea hexagyna (SY-197) and Artemisia monosperma (SY-198) have anti-microbial activity against the most of tested bacteria, fungi and yeast. Whereas (SY- 181), the extracts of Teucrium oliverianum (SY-175), Zilla spinosa (SY-187), and Rhazya stricta (SY-195) have poor action against the tested bacteria, fungi and yeast. Conclusion: The antimicrobial activity of plant extracts against bacteria was more effective than against fung

NAD(P)H:quinone oxidoreductase 1 inducer activity of some novel anilinoquinazoline derivatives

The Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response elements pathway enables cells to survive oxidative stress conditions through regulating the expression of cytoprotective enzymes such as NAD(P)H:quinone oxidoreductase 1 (NQO1). This work presents the design and synthesis of novel anilinoquinazoline derivatives (2–16a) and evaluation of their NQO1 inducer activity in murine cells. Molecular docking of the new compounds was performed to assess their ability to inhibit Keap1–Nrf2 protein–protein interaction through occupying the Keap1–Nrf2-binding domain, which leads to Nrf2 accumulation and enhanced gene expression of NQO1. Docking results showed that all compounds can potentially interact with Keap1; however, 1,5-dimethyl-2-phenyl-4-(2-phenylquinazolin-4-ylamino)-1,2-dihydropyrazol-3-one (9), the most potent inducer, showed the largest number of interactions with key amino acids in the binding pocket (Arg483, Tyr525, and Phe478) compared to the native ligand or any other compound in this series