GC-MS Based Chemical Profiling and Evaluation of Antioxidant Potential of Leaves and Stems of Alternanthera Sessilis Red from Sabah, Malaysia

Objectives: The aim of the current study was to perform phytochemical screening and determination of total phenolics, total flavonoids and antioxidant activity of various crude extracts of Alternanthera sessilis red leaves. Methods: Determination of antioxidant nature of Alternanthera sessilis red was carried out by DPPH radical scavenging method. GC-MS analysis of various crude extracts resulted in the presence of different types of low and high molecular weight compounds consisting of carbohydrates, fatty acid and vitamins. Results: Among all the extracts, methanol extracts exhibited higher DPPH radical scavenging activity with IC50 value of 0.183 mg/ml. BHT used as the positive control showed IC50value of 0.089 mg/mL. The results suggested that the crudes extracts of Alternanthera sessilis red exhibit moderate antioxidant activity. The total phenolic content (279.8 ± 0.02 mg GAE/g) and total flavonoid content (250.7 ± 0.03 mg QE/g) in methanol was estimated higher as compared to other solvents. Conclusion: The total flavonoid content and total phenolic content were found to be higher in methanolic extract followed by ethyl acetate  and hexane extracts

3β-Chloro-6-[2-(2-cyano­acet­yl)hydrazin-1-yl­idene]-5α-cholestane

The asymmetric unit of the title compound, C30H48ClN3O, contains two mol­ecules, A and B. In both mol­ecules, the three cyclo­hexane rings in the steroid fused ring systems adopt chair conformations, while the cyclo­pentane rings adopt envelope and twist conformations in mol­ecules A and B, respectively. In mol­ecule B, the cyano group is disordered over two orientations with refined site-occupancies of 0.593 (8) and 0.407 (8). An intra­molecular C—H⋯N inter­action forms an S(10) ring in both mol­ecules. In the crystal, mol­ecules are linked by N—H⋯O, C—H⋯O and C—H⋯N inter­actions, resulting is chains propagating along the a-axis direction

Determination of total phenolic content, total flavonoid content and antioxidant activity of various organic crude extracts of licuala spinosa leaves from Sabah, Malaysia

In this study, the leaves of Licuala spinosa were used to determine the total phenolic and flavonoid content as well as antioxidant activity of different crude extracts. The samples were extracted successively with organic solvents such as hexane, chloroform and ethyl acetate respectively. The total phenolic content was determined by Folin-Ciocalteu’s assay. Chloroformcrude extract showed the highest total phenolic content (9.42± 0.06 mg GAE/g), followed by ethylacetate crude extract (8.91± 0.06 mg GAE/g) and hexane crude extract (6.78±0.26 mg GAE/g).The total flavonoid content was determined by Aluminium chloride colometric assay and expressedas QE equivalent. Chloroform crude extract showed the highest total flavonoid content (8.96 ± 0.21mg QE/g), followed by ethyl acetate crude extract (7.04 ± 0.02 mg QE/g) and hexane crude extract(3.05 ± 0.09 mg QE/g). The antioxidant activity of extracts were evaluated by 2,2-diphenyl-1-picyhydrazyl (DPPH) assay. In DPPH assay, IC50 values were used to determine the antioxidant potential of the sample. The lower the IC50 value, the higher the antioxidative property. Among allthe extracts, chloroform extracts exhibited higher DPPH radical scavenging activity with IC50 value of 0.032 mg /mL. BHT used as the positive control showed IC50 value of 0.089 mg/m

Determination of Chemical Composition, Total Flavonoid Content, Total Phenolic Content and Antioxidant Capacity of Various Crude Extracts of Manihot esculenta Crantz Leaves

In the present study, the leaves of Manihot esculenta Crantz were extracted by various organic solvents viz. hexane, chloroform, ethyl acetate and subjected to GC-MS analysis to determine their chemical composition and antioxidant activity by DPPH assay. The GC-MS analysis of hexane extract displayed squalene (10.25%), 9-octadecenoic acid (Z)-, methyl ester (9.01%), phytol (8.71%) and hexadecanoic acid, methyl ester (8.33%) as major compounds. The major compounds present in the chloroform extract were β-amyrin (12.70%), phytol (11.35%), 1,4-methanoazulen-9-ol, decahydro-1,5,5,8atetramethyl-,[1R- (1α,3aβ,4α,8aβ,9S*)]- (10.98%), 6β-Bicyclo[4.3.0]nonane, 5β-iodomethyl-1β-isopropenyl-4α,5α-dimethyl-, (9.40%) and humulane-1,6-dien-3-ol (8.53%). In ethyl acetate extract, squalene (16.39%), 9,11-dimethyltetracyclo [7.3.1.0(2.7).1(7.11)]tetradecane (12.01%) and humulane-1,6-dien-3-ol (9.58%) were reported as major compounds. The total phenolic content for hexane, chloroform and ethyl acetate was 5.35 ± 0.66 mg GAE/g, 7.52 ± 0.09 mg GAE/g and 13.47 ± 0.56 mg GAE/g, respectively. Whereas the total flavonoid content for hexane, chloroform and ethyl acetate was 0.89 ± 0.17 mg QE/g, 2.69 ± 0.09 mg QE/g and 6.66 ± 0.94 mg QE/g, respectively. The antioxidant activity of ethyl acetate extract (IC50 = 0.19 mg/mL) was higher than chloroform (IC50 = 1.39 mg/mL) and hexane extracts (IC50 = 1.74 mg/mL), with respect to the standard butylatedhydroxytoluene (BHT) (IC50 = 0.04 mg/mL)

GC-MS analysis of chemical constituents and in vitro antioxidant activity of the organic extracts from the stem of Bridelia stipularis

In the present study the stems of the Bridelia stipularis (L.) Blume, which is traditionally used by ethnic communities in Sabah, Malaysia, has been investigated for its chemical composition, total flavonoid content (TFC) and total phenolic content (TPC) via Gas-Chromatography-Mass Spectroscopy (GC-MS) analysis consuming hexane, chloroform and ethyl acetate as extraction solvents and gallic acid and quercetin as internal standards. In vitro antioxidant activity (AA) was determined by the application of 1,1-diphenyl-2-picryl hydrazine (DPPH) radical scavenging assay using tert-butyl-1-hydroxytoluene (BHT) as comparative drug. The GC-MS profiling showed the presence of 1-dodecanol (40.917%), oxalic acid, cyclobutyl octadecyl ester (24.985%), 1-octanol,2-nitro (12.424%), benzaldehyde, 2,4-dimethyl- (9.583%), 4-tridecanol (6.359%) and nitric acid, nonyl ester (5.616%) as major constituents. The TPC (224.62 ± 0.08 mg QE/g) and TFC (160.48 ± 0.08 mg GAE/g) was reported highest for the most polar solvent i.e. ethyl acetate. The in vitro antioxidant study disclosed highest IC50 value for ethyl acetate (2.15 mg/mL), queued by chloroform (1.19 mg/mL) and hexane (0.89 mg/mL), displaying that polar solvents are good extraction solvents for the identification of free radical scavenging properties, TFC and TPC

Chemical composition and antioxidant activity of essential oil of leaves and flowers of Alternanthera sessilis red from Sabah

In the present study, chemical composition and antioxidant activity of essential oil from the aerial parts of Alternanthera sessilis red has been investigated. The chemical composition of essential oil of A. sessilis red was determined by GC-MS analysis. Determination of antioxidant nature of A. sessilis red was carried out by 1,1- diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method using butylated hydroxytoulene (BHT)as the positive control. The major components of essential oil of leaves, as analyzed by the GC-MS were found to be 1,1,1,5,5,5-hexamethyl-3,3-bis[trimethylsilyl)oxy]trisiloxane (15.43%), S,S-dioxide trans-2-methyl-4-Npentylthiane (11.27%), didodecylphthalate (10.62%) and tetrahydro-2,5-dimethoxy furan (10.01%).However, the major components of essential oil of flower were 1,1,1,5,5,5-hexamethyl-3,3- bis[trimethylsilyl)oxy]trisiloxane (17.76%), trans-4-ethyl-5-octyl-2,2-bis(trifluromethyl)-1,3-dioxolane (11.12%) and tetrahydro-2,5-dimethoxy furan ( 9.10%)

3β-Chloro-5α-cholestan-6-one

The asymmetric unit of the title compound, C27H45ClO, consists of two crystallographically independent mol­ecules. In both mol­ecules, the three cyclo­hexane rings in the steroid fused-ring systems adopt chair conformations, while the cyclo­pentane ring adopts a half-chair conformation in one mol­ecule and an envelope conformation in the other. In the crystal, the mol­ecules are linked into a two-dimensional network by weak C—H⋯O hydrogen bonds. The crystal studied is a nonmerohedral twin with a refined ratio of twin components of 0.264 (3):0.736 (3)

3β-Acet­oxy-5α-cholestan-6-one 2-cyano­acetyl­hydrazone

The asymmetric unit of the title compound, C32H51N3O3, consists of two crystallographically independent mol­ecules, A and B; the 2-methyl­pentane group of mol­ecule A and the propane group of mol­ecule B are each disordered over two sets of sites, with refined site-occupancies of 0.825 (5):0.175 (5) and 0.630 (18):0.370 (18), respectively. In both mol­ecules, the three cyclo­hexane rings in the steroid fused ring systems adopt chair conformations while the cyclo­pentane rings adopt envelope and twist conformations in mol­ecules A and B, respectively. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds link the two independent mol­ecules together, generating R 2 1(7) and R 2 2(8) ring motifs

Molecular docking studies of coumarin hybrids as potential acetylcholinesterase, butyrylcholinesterase, monoamine oxidase A/B and β-amyloid inhibitors for Alzheimer’s disease

Abstract Coumarins are the phytochemicals, which belong to the family of benzopyrone, that display interesting pharmacological properties. Several natural, synthetic and semisynthetic coumarin derivatives have been discovered in decades for their applicability as lead structures as drugs. Coumarin based conjugates have been described as potential AChE, BuChE, MAO and β-amyloid inhibitors. Therefore, the objective of this review is to focus on the construction of these pharmacologically important coumarin analogues with anti-Alzheimer’s activities, highlight their docking studies and structure–activity relationships based on their substitution pattern with respect to the selected positions on the chromen ring by emphasising on the research reports conducted in between year 1968 to 2017

GC-MS analysis of chemical constituents and in vitro antioxidant activity of the organic extracts from the stem of Bridelia stipularis

In the present study the stems of the Bridelia stipularis (L.) Blume, which is traditionally used by ethnic communities in Sabah, Malaysia, has been investigated for its chemical composition, total flavonoid content (TFC) and total phenolic content (TPC) via Gas-Chromatography-Mass Spectroscopy (GC-MS) analysis consuming hexane, chloroform and ethyl acetate as extraction solvents and gallic acid and quercetin as internal standards. In vitro antioxidant activity (AA) was determined by the application of 1,1-diphenyl-2-picryl hydrazine (DPPH) radical scavenging assay using tert-butyl-1-hydroxytoluene (BHT) as comparative drug. The GC-MS profiling showed the presence of 1-dodecanol (40.917%), oxalic acid, cyclobutyl octadecyl ester (24.985%), 1-octanol,2-nitro (12.424%), benzaldehyde, 2,4-dimethyl- (9.583%), 4-tridecanol (6.359%) and nitric acid, nonyl ester (5.616%) as major constituents. The TPC (224.62 ± 0.08 mg QE/g) and TFC (160.48 ± 0.08 mg GAE/g) was reported highest for the most polar solvent i.e. ethyl acetate. The in vitro antioxidant study disclosed highest IC50 value for ethyl acetate (2.15 mg/mL), queued by chloroform (1.19 mg/mL) and hexane (0.89 mg/mL), displaying that polar solvents are good extraction solvents for the identification of free radical scavenging properties, TFC and TPC