The Antibacterial, Antioxidant and Phytochemical Composition of Combretum tanaense (J. Clark) Root Extracts

Aims: To evaluate the antibacterial, antioxidant and phytochemical composition of Combretum tanaense extracts. Study Design: Laboratory-experimental design was used in this study. Place and Duration of Study: Fresh roots of Combretum tanaense were obtained from Mount Kenya University botanical garden in Thika (Kiambu County-Kenya). The study was carried out between November 2017 and February 2018 at Mount Kenya University Biochemistry and Pharmacognosy laboratories. Methodology: Duplicate voucher specimens were prepared and deposited at the East Africa herbarium housed at the National Museums of Kenya and Mount Kenya University herbarium. Extraction of total extracts of C. tanaense roots was conducted according to standard procedures. Agar well diffusion and 2-2-diphenyl picryl hydrazyl (DPPH) assay methods were used to evaluate antibacterial and free radical scavenging activities of the extracts. All assays were performed in triplicate. Antibacterial data was presented as a mean zone of inhibition ± SEM while free radical scavenging activities were expressed regarding IC50. Phytochemical screening was carried out using standard procedures to ascertain the presence or absence of various phytochemical groups in the test plant. Results: The current study indicated that Combretum tanaense root extracts had antibacterial activities against the selected gram-positive and gram-negative bacterial strains. The highest activity was recorded against gram-negative bacteria (Haemophilus influenza) by exhibiting inhibition zones of 13.32±0.15 mm and 12.82±0.36 mm for methanol and water extracts respectively. Antioxidant activities for both methanol and water extracts were ten times higher compared to that of standard (L-ascorbic acid). The extracts were found to have saponins, phenols including tannins and glycosides. Conclusion: Extracts of Combretum tanaense have compounds that exhibit antibacterial and antioxidant activities. From the results obtained, the ability of the extracts to inhibit bacterial growth and scavenge for free radicals was due to the presence of phenolic compounds and will be attributed to the healing properties of this plant. This study recommends further studies including toxicity and isolation of active compounds for the development of products with pharmaceutical value.

Conocarpus erectus L., a plant with a high content of structural sugars, ions and phenolic compounds, shows antioxidant and antimicrobial properties promoted by different organic fractions

Objective: To evaluate the structural and chemical composition of plant and the antioxidant and antimicrobial activities promoted by hexanic, ethanolic and ethyl acetate fractions obtained from leaves of Conocarpus erectus. Methods: Organic fractions were characterized through UPLC-MS and GC-MS. Antioxidant potential was performed through DPPH and molybdenum phosphate techniques. Antibacterial and antifungal assays were performed in accordance with Clinical and Laboratory Standards Institute protocols. Results: The obtained biomass of Conocarpus erectus leaves showed the high presence of glucose (0.45 g/L), cellulose (28.69%), Na (55.126 μg/L) and K (31.163 μg/L). We identified seven compounds in the hexanic and ethyl acetate fractions, and eight compounds in ethanolic fraction. Moreover, phenolic compounds are prevalent in all organic fractions with values of (10.04 ± 0.24), (221.26 ± 1.84), (340.53 ± 0.84) mg/g GAE to hexanic, ethyl acetate and ethanolic fraction, respectively. Antioxidant results showed a high potential in ethyl acetate fraction (71.82 ± 6.87)% and (10.89 ± 0.05)% in DPPH and molybdenum phosphate techniques, respectively. The ethanolic fraction showed moderate bacteriostatic and bactericidal activity against Staphylococcus aureus and presented a high fungistatic potential for all Candida species tested. Conclusions: Organic fractions obtained from leaves of Conocarpus erectus present antimicrobial and antioxidant properties, and these findings contribute to scientific information for the effectiveness on use of this plant in the development of a phytotherapic compound.

Conocarpus erectus L., a plant with a high content of structural sugars, ions and phenolic compounds, shows antioxidant and antimicrobial properties promoted by different organic fractions

Objective: To evaluate the structural and chemical composition of plant and the antioxidant and antimicrobial activities promoted by hexanic, ethanolic and ethyl acetate fractions obtained from leaves of Conocarpus erectus. Methods: Organic fractions were characterized through UPLC-MS and GC-MS. Antioxidant potential was performed through DPPH and molybdenum phosphate techniques. Antibacterial and antifungal assays were performed in accordance with Clinical and Laboratory Standards Institute protocols. Results: The obtained biomass of Conocarpus erectus leaves showed the high presence of glucose (0.45 g/L), cellulose (28.69％), Na (55.126 μg/L) and K (31.163 μg/L). We identified seven compounds in the hexanic and ethyl acetate fractions, and eight compounds in ethanolic fraction. Moreover, phenolic compounds are prevalent in all organic fractions with values of (10.04 ± 0.24), (221.26 ± 1.84), (340.53 ± 0.84) mg/g GAE to hexanic, ethyl acetate and ethanolic fraction, respectively. Antioxidant results showed a high potential in ethyl acetate fraction (71.82 ± 6.87)％ and (10.89 ± 0.05)％ in DPPH and molybdenum phosphate techniques, respectively. The ethanolic fraction showed moderate bacteriostatic and bactericidal activity against Staphylococcus aureus and presented a high fungistatic potential for all Candida species tested. Conclusions: Organic fractions obtained from leaves of Conocarpus erectus present antimicrobial and antioxidant properties, and these findings contribute to scientific information for the effectiveness on use of this plant in the development of a phytotherapic compound.

Identificación de ácidos polifenólicos en el extracto metanólico de las hojas de terminalia catappa Linn / Identification of polyphenolic acids in the methanolic extract from Terminalia catappa Linn leaves

INTRODUCCIÓN: diferentes extractos de Terminalia Catappa Linn. (Combretaceae) han demostrado de forma internacional, propiedades farmacológicas beneficiosas para la salud humana. Estas propiedades han sido atribuidas en lo fundamental a los polifenoles y glicósidos, encontrados en hojas, corteza y frutos. En Cuba esta especie es catalogada como una planta invasora y existen pocas investigaciones sobre su composición química y estudios farmacológicos. OBJETIVOS: identificar y cuantificar los ácidos polifenólicos presentes en el extracto metanólico de las hojas de T. catappa utilizándose la cromatografía de gases acoplada a espectrometría de masas. MÉTODOS: las hojas amarillo-rojizas fueron secadas, molidas, desgrasadas con hexano y y con posterioridad extraídas con metanol en un baño ultrasónico. El extracto se filtró y el disolvente se eliminó al vacío. El extracto seco se hidrolizó con ácido clorhídrico y se extrajo con acetato de etilo. Se determinó el rendimiento de extracción, las características organolépticas y los polifenoles totales mediante el método de Follin-Ciocalteu. La composición química del extracto hidrolizado se llevó a cabo por cromatografía de gases acoplada a espectrometría de masas, previa formación de los derivados trimetilsilil. RESULTADOS: se obtuvo un líquido de color pardo rojizo oscuro de olor característico. El contenido total de polifenoles fue 184,6 (mg Pirogalol/100 g Extracto). Se detectaron 37 compuestos por cromatografía de gases acoplada a espectrometría de masas en el extracto metanólico hidrolizado. Este extracto está compuesto de manera general por ácidos polifenólicos como el ácido gálico; ácido vanílico; ácido 3,4-dihidroxibenzoico; ácido 2,5-dihidroxi-benzoico y ácido 4- hidroxibenzoico. También se detectaron otros compuestos con elevados contenidos como ácido elágico y ácido levulínico. CONCLUSIONES: el extracto metanólico de hojas de T. catappa que crece en Cuba mostró un elevado contenido de ácidos polifenólicos, donde los ácidos gálico y elágico fueron los mayoritarios. La presencia de estos compuestos pudiera justificar las propiedades medicinales atribuidas a esta especie, a la vez que servirían de base para continuar con futuras pruebas farmacológicas que avalen sus usos con fines farmacéuticos.

INTRODUCTION: Different extracts of Terminalia Catappa Linn. (Combretaceae) internationally have shown pharmacological properties beneficial to human health. These properties have been largely attributed to polyphenols and their glycosides found in the leaves, bark and fruits. In Cuba this species is listed as an invasive plant and there is limited research on its chemical composition and pharmacological studies. OBJECTIVES: To identify and quantify the polyphenolic acids that could be present in the methanol extract of Terminalia catappa leaves using gas chromatography-mass spectrometry. METHODS: The yellow-red leaves were dried, ground, defatted with hexane and then extracted with methanol in an ultrasonic bath. The extract was filtered and the solvent removed under vacuum. The dry extract was hydrolyzed with hydrochloric acid and extracted with ethyl acetate. The extraction yield, the organoleptic characteristics and the total polyphenols by Follin-Ciocalteu method were determined. The chemical composition of the hydrolyzed extract was performed by gas chromatography-mass spectrometry after formation of trimethylsilyl derivatives. RESULTS: A dark reddish brown liquid with a characteristic odor was obtained. The total polyphenol content was 184.6 (mg Pyrogallol/100g extract). By mean of gas chromatography-mass spectrometry a total of 37 compounds were detected in the hydrolyzed methanol extract. This extract consists mainly of polyphenolic acids such as gallic acid; vanillic acid; 3,4-dihydroxybenzoic acid; 2,5-dihydroxybenzoic acid and 4- hydroxybenzoic acid. Other compounds with high content as ellagic acid and levulinic acid were also detected. CONCLUSIONS: The methanolic extract obtained from the leaves of Terminalia catappa growing in Cuba showed a high content of polyphenolic acids where gallic acid and ellagic predominated. The presence of these compounds could justify the medicinal properties attributed to this species, while providing the basis for further future pharmacological evidence to support its use for pharmaceutical purposes.

Anti- Sporothrix spp. activity of medicinal plants

ABSTRACT Cases of sporotrichosis in humans and animals without satisfactory clinical response have increased, a warning sign of strains resistant to conventional antifungal agents. The urgent search for alternative therapies was an incentive for research on medicinal plants with anti-Sporothrix spp. properties. A bibliographic survey was performed based on scientific papers about in vitro and in vivo antifungal activity of essential oils and extracts of plants in differents solvents against the fungal of the Sporothrix schenckii complex. The study methodology consisted of a literature review in Google Scholar, Science Direct, Pubmed, Bireme and Springer link with papers from 1986 to 2015. We found 141 species of plants that were investigated, of which 100 species were concentrated in 39 botanical families that had confirmed anti-Sporothrix activity. Combretaceae, Asteraceae and Lamiaceae represented the botanical families with the greatest number of plants species with antifungal potential, using different methodologies. However, there are few studies with medicinal plants in experimental infection in animals that prove their activity in the treatment of sporotrichosis. It reinforces the need for further research related to standardization of in vitro methodologies and in vivo studies related to safety and to toxicity potential of these plants with anti-Sporothrix spp. activity.

RESUMO Casos de esporotricose em humanos e animais sem resposta clínica satisfatória têm aumentado, sinal de alarme para o surgimento de cepas resistentes aos antifúngicos convencionais. A urgente busca por alternativas terapêuticas tem incentivado as pesquisas em plantas medicinais com atividade anti-Sporothrix spp. Um levantamento bibliográfico foi realizado com base em artigos científicos sobre a atividade antifúngica in vitro e in vivo de óleos essenciais e extratos de plantas preparados em diferentes solventes contra o complexo Sporothrix schenckii. A metodologia do estudo consistiu em uma revisão bibliográfica em Google Scholar, Science Direct, Pubmed, Bireme e Springer link com artigos desde 1986 até 2015. Foram encontradas 141 espécies de plantas já investigadas, das quais 100 espécies concentradas em 39 famílias botânicas apresentaram atividade anti-Sporothrix spp. confirmada. Combretaceae, Asteraceae e Lamiaceae representaram as famílias botânicas com maior número de espécies vegetais com potencial antifúngico, empregando diferentes metodologias. Entretanto, há poucos estudos com plantas medicinais em infecção experimental animal comprovando sua atividade no tratamento da esporotricose. Reforça-se a necessidade de mais pesquisas relacionadas à padronização de metodologias in vitro e a estudos in vivo relacionados à segurança e potencial tóxico dessas plantas com atividade anti-Sporothrix spp.

Bioassay Guided Isolation and Evaluation of the Antidiabetic Principles of Combretum dolichopetalum Root.

Aims: The present study was aimed at investigating the antidiabetic potentials of Combretum dolichopetalum root in alloxan-induced animals with the hope of isolating its antidiabetic principles. Study Design: Sixty four Wistar albino rats of either sexes were randomly segregated into 16 groups (n=4). Also, thirty two albino mice were segregated into 8 groups. These received various doses of the plant sample, vehicle or glibenclamide for the antidiabetic study. Place and Duration of Study: This study was done in the laboratory of the Department of Pharmaceutical and Medicinal Chemistry, University of Nigeria, Nsukka between March and October, 2013. Methodology: The root of C. dolichopetalum was extracted with methanol (ME) and fractionated successively with various solvents (n-hexane, chloroform, ethylacetate, methanol and water) to afford the respective fractions: HF, CF, EF, MF and AF. CF was further fractionated to afford six sub-fractions: C1-C6. Acute toxicity study was done using ME. Antidiabetic activity of various doses (p.o.) of ME (100, 200, 400 and 600 mg/kg body weight), its fractions (200 and 400 mg/kg) and sub-fractions (200 mg/kg), glibenclamide (0.2 mg/kg) and vehicle (control) were investigated in alloxan-induced (i.p.) diabetic animals for 9 h. Phytochemical analysis was also carried on ME and fractions. Results: The extract was considered safe with LD50 greater than 5000 mg/kg. ME (400 mg/kg), CF (400 mg/kg) and C3 (200 mg/kg) produced maximum reduction (36.78%, 72.43% and 83.17% respectively) in fasting blood glucose of animals after 9 h which were significantly (P < .01, P < .001) different from the control and better than glibenclamide (48.18%). Phytochemical analysis showed alkaloids, flavonoids, terpens and steroids as the likely antidiabetic agent(s). Conclusion: The root of C. dolichopetalum possesses potent antidiabetic activity which increases as the extract is purified. The antidiabetic effect of the plant may likely be due to the presence of alkaloids, flavonoids, terpens or steroids.

In vitro Modulation of Pancreatic Insulin Secretion and Extra Pancreatic Insulin Action, Enzymatic Starch Digestion and Protein Glycation by Terminalia chebula Extracts.

Aim: Traditional plant treatments have been used throughout the world for the therapy of diabetes mellitus. Study Design: Using multiple in vitro models; this study was designed to investigate the efficacy and mode of action of Terminalia chebula Retz. (Combretaceae) used traditionally for treatment of diabetes. Place and Duration of Study: School of Biomedical Sciences, University of Ulster, 2001- 2004. Results: T. chebula aqueous extract stimulated basal insulin output and potentiated glucose-stimulated insulin secretion concentration-dependently in the clonal pancreatic beta cell line, BRIN-BD11 (p<0.001). The insulin secretory activity of plant extract was abolished in the absence of extracellular Ca2+ and by inhibitors of cellular Ca2+ uptake, diazoxide and verapamil, (p<0.001). Furthermore, the extract increased insulin secretion in depolarised cells and augmented insulin secretion triggered by IBMX, but not by tolbutamide or glibenclamide. T. chebula extract did not display insulin mimetic activity but it enhanced insulin-stimulated glucose transport in 3T3 L1 adipocytes by 280% (p<0.001). At (0.5-5.0mg/mL) concentrations, the extract also produced 22-84% (p<0.001) decrease in starch digestion In vitro and inhibited protein glycation (p<0.001) at 1mg/ml aqueous extract. Conclusion: This study has revealed that water soluble bioactive principles in T.chebula extract stimulate insulin secretion, enhance insulin action and inhibit both protein glycation and starch digestion. The former actions are dependent on the bioeffective component(s) in the plant being absorbed intact. Future work assessing the use of Terminalia chebula as dietary adjunct or as a source of active antidiabetic agents may provide new opportunities for the treatment of diabetes