ABSTRACT
The antioxidant activity and the inhibitory potential of α-amylase of lyophilized hydroethanolic extracts of Conocarpus erectus leaves obtained by ultrasonication were determined. The most potent extract was subjected to ultra-high performance liquid chromatography system equipped with mass spectrometer for metabolite identification. The identified metabolites were docked in α-glucosidase to assess their binding mode. The results revealed that 60% ethanolic extract exhibited highest ferric reducing antioxidant power (4.08 ± 0.187 mg TE/g DE) and α-amylase inhibition (IC50 58.20 ± 1.25 µg/mL. The metabolites like ellagic acid, 3-O-methyl ellagic acid, ferujol, 5, 2 Ì-dihydroxy-6,7,8-trimethyl flavone and kaempferol glucoside were identified in the extract and subjected to molecular docking studies regarding α-amylase inhibition. The comparison of binding affinities revealed 3-O-methyl ellagic acid as most effective inhibitor of α-amylase with binding energy of -14.5911 kcal/mol comparable to that of acarbose (-15.7815 kcal/mol). The secondary metabolites identified in the study may be extended further for functional food development with antidiabetic properties.
Se determinó la actividad antioxidante y el potencial inhibidor de la α-amilasa de extractos hidroetanólicos liofilizados de hojas de Conocarpus erectus obtenidos por ultrasónicación. El extracto más potente se sometió a un sistema de cromatografía líquida de ultra alto rendimiento equipado con un espectrómetro de masas para la identificación de metabolitos. Los metabolitos identificados se acoplaron en α-glucosidasa para evaluar su modo de unión. Los resultados revelaron que el extracto etanólico al 60% exhibió el mayor poder antioxidante reductor férrico (4.08 ± 0.187 mg TE/g DE) e inhibición de la α-amilasa (IC50 58.20 ± 1.25 µg/mL. Los metabolitos como el ácido elágico, 3-O-metil elágico ácido, ferujol, 5, 2 Ì-dihidroxi-6,7,8-trimetil flavona y kaempferol glucósido se identificaron en el extracto y se sometieron a estudios de acoplamiento molecular con respecto a la inhibición de la α-amilasa. La comparación de las afinidades de unión reveló 3-O-metil El ácido elágico como inhibidor más eficaz de la α-amilasa con una energía de unión de -14,5911 kcal/mol comparable a la de la acarbosa (-15,7815 kcal/mol). Los metabolitos secundarios identificados en el estudio pueden ampliarse aún más para el desarrollo funcional de alimentos con propiedades antidiabéticas.
Subject(s)
Plant Extracts/chemistry , alpha-Amylases/antagonists & inhibitors , Myrtales/chemistry , Antioxidants/chemistry , Benzopyrans/analysis , In Vitro Techniques , Plant Extracts/pharmacology , Plant Leaves/chemistry , Molecular Docking Simulation , Antioxidants/pharmacologyABSTRACT
Conocarpus erectus L. (Family Combretaceae) is an introduced plant species, widely spread in Jeddah City, and other parts of Saudi Arabia. Folk medicine has used Parts of this species in its native countries. In the present work four different concentrations of ethanol extracts (50; 100; 150 & 200ppm) from different parts of this plant (seeds, stem, leaves and bark) were assessed against three Gram+ve bacteria (Bacillus subtilius, Micrococcus luteus, Staphylococcus aureus) and three Gram-ve bacteria (Escherichia coli, Pseudomonas aeruginosa & Klebsiella pneumoniae).The effect magnitude of these extracts on tested bacteria strains was as follows: leaves extracts bark stem seeds. Nevertheless results showed a strong activity of all thesedifferent parts against Staphylococcus aureus among the Gram+ve bacteria. The maximum inhibitory effect was observed at 200 μL /dish by all used parts extracts except the bark extract against Pseudomonas aeruginosa, followed by Escherichia coli and Klebsiella pneumoniae among the Gram–Ve bacteria. The Random Amplified Polymorphic DNA (RAPD) assay was used to assess the level of DNA damage in treated bacteria strains. The results confirmed the potentials of Conocarpus erectus as good antibacterial source. Worth noting that the present report, is the first on the antibacterial and molecular characterization of bacteria strains by Conocarpus erectus, growing in the west coast of Saudi Arabia. In conclusion we recommend more innovative investigations, in order to explore the treasures of this therapeutically important plant species.
ABSTRACT
The use of plants and their derived substances increases day by day for the discovery of new therapeutic agents owing to their versatile applications. Conocarpus erectus L. (family Combretaceae) is one of two species in the genus Conocarpus widely spread in Taif and other parts of the Kingdom of Saudi Arabia. It is used in some countries as folk remedy for anemia, catarrh, conjunctivitis, diabetes, diarrhea and fever. To our knowledge from literatures there is little work about phytochemical contents and biological activities of C. erectus which encouraged the authors to carry out this study. The four defatted methanol extracts of C. erectus different parts (leaves, stems, fruits and flowers) showed high free radical scavenging activity toward DPPH radical with SC50 between 6.47-9.4 μg/ml. The n- BuOH fractions obtained from successive fractionation of the four defatted methanol extracts had radical scavenging activity with SC50 between 4.43-5.89 μg/ml higher than the EtOAc fractions (7.04-10.71 μg/ml). Due to the high antioxidant activity of the EtOAc and n-BuOH fractions, it was in vitro assayed toward two human cancer cell lines; HepG2 & MCF-7; using Sulphorhodamine-B assay method. The results showed that most fractions had cytotoxic activity with IC50< 20μg/ml which fall within the American Cancer Institute criteria. A preliminary antibacterial screening of the four defatted methanol extracts of the different parts toward five bacterial strains were done. Phytochemical investigation of the EtOAc and n-BuOH fractions showed that phenolic compounds constitute the major components of it. In conclusion this is the first report on the phytochemical and biological properties of Conocarpus erectus growing in Taif governorate, KSA. More in vivo and in vitro studies along with detailed phytochemical investigation are needed in the hope to can use this plant (crude extract, fractions, sub-fractions or pure compounds) in the prevention and therapies of some diseases.