Isolation and characterization of resveratrol oligomers from the stem bark of Hopea ponga (Dennst.) Mabb. And their antidiabetic effect by modulation of digestive enzymes, protein glycation and glucose uptake in L6 myocytes

2019 ◽  
Vol 236 ◽  
pp. 196-204 ◽  
Author(s):  
P. Sasikumar ◽  
K. Lekshmy ◽  
S. Sini ◽  
B. Prabha ◽  
N. Anil Kumar ◽  
...  
2018 ◽  
Vol 30 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Erum Iqbal ◽  
Linda B.L. Lim ◽  
Kamariah Abu Salim ◽  
Shaheen Faizi ◽  
Ayaz Ahmed ◽  
...  

2021 ◽  
Vol 38 (1) ◽  
pp. 1-5
Author(s):  
Md Arifur Rahman ◽  
Ahmed Abu Rus’d ◽  
Md Enamul Haque

Sonneratia apetala (S. apetala) (Lythraceae) has been investigated for the isolation and characterization of antimicrobial compounds and evaluation of their biological activities. The chloroform extract of the stem bark and different partitionate of the chloroform extracts i.e. Petroleum ether soluble fraction (PESF), Ethyl acetate soluble fraction(EASF), Methanol soluble fraction(MSF) and aqueous soluble fractions (ASF) were subjected to different chromatographic techniques to isolate secondary metabolites. Successive chromatographic separation and purification yielded a total of two compounds identified and characterized as Taraxerone(1) and 5,8-dihydroxy- 6-methoxy-4,9-dioxo-1,3,4,9-tetrahydronaphthol[2,3-c]furan-1-yl acetate (2) by extensive proton NMR spectrum (1H-NMRspectrum) analysis. The different partitionate like PESF, EASF, MESF and ASF were subjected to screen their antimicrobial properties against some selected Gram positive and Gram negative bacteria and fungi, brine shrimp lethality and antioxidant activities. The maximum zone of inhibition of chloroform extract was found against Pseudomonas sp. (16mm). All fractions showed more activity against Gram negative bacteria then Gram positive bacteria. In the brine shrimp lethality bioassay, among all extracts, the petroleum ether and ethyl acetate soluble fraction showed significant lethality having the LC50 value of 7.72 μg/ml. The antioxidant activity was evaluated in terms of determination of free radical scavenging activity (DPPH assay). Among all the extracts of S. apetala the highest free radical scavenging activity showed by (Methanol soluble fraction) MESF with IC50 value 18.0 μg/ml. Bangladesh J Microbiol, Volume 38, Number 1, June 2021, pp 1-5


2012 ◽  
Vol 7 (7) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Harish C. Upadhyay ◽  
Natasha Jaiswal ◽  
Akhilesh K. Tamrakar ◽  
Arvind K. Srivastava ◽  
Namita Gupta ◽  
...  

The serial chromatographic separation of chloroform and n-butanol fractions of Ammannia multiflora resulted in the isolation and characterization of 4-hydroxy-α-tetralone (1) and 3,3′-(2 R,5 R)-tetrahydrofuran-2,5-diyldiphenol (ammaniol, 2). Compound 1 was chemically modified into six semi-synthetic acyl and aryl derivatives (1A - 1F). The isolated compounds 1 and 2 along with semi-synthetic derivatives 1A - 1F were evaluated for in vitro antihyperglycemic activity employing 2-deoxyglucose uptake by L-6 rat muscle cell lines. The results indicated that both the isolates, as well as derivatives (1A - 1F), have the property to stimulate glucose uptake. Ammaniol (2) increased glucose uptake significantly (64.8%), while one of the aryl derivatives of 1, 4- O-(3,4,5-trimethoxybenzoyl)-α-tetralone (1D), showed potent antihyperglycemic activity and increased glucose uptake by 94.6%, even more than rosiglitazone (88.8%). Further, since 1D possesses better antihyperglycemic activity than rosiglitazone (standard), this might be a new safer antidiabetic drug of herbal origin.


RSC Advances ◽  
2016 ◽  
Vol 6 (80) ◽  
pp. 77075-77082 ◽  
Author(s):  
P. Sasikumar ◽  
B. Prabha ◽  
T. R. Reshmitha ◽  
Sheeba Veluthoor ◽  
A. K. Pradeep ◽  
...  

The remarkable α-glucosidase inhibition exhibited by the acetone extract of the rhizome of Ampelocissus indica (L.) and stem bark of Vateria indica Linn. (IC50 23.2 and 1.47 μg mL−1) encouraged us to isolate the phytochemicals from these plants.


2018 ◽  
Vol 1 (2) ◽  
Author(s):  
A. Kwaji ◽  
H. M. Adamu ◽  
I. Y. Chindo ◽  
R. Atiko

The present study is aimed at the isolation and characterization of betulin from Entada africana.  A dichloromethane soluble portion of the stem bark methanol/acetone (1:1 v/v) extract was subjected to gradient elution using ethyl acetate in hexane (5 – 30 %) on an open column. A pure compound was obtained with Rf = 0.61 in hexane/ethyl acetate (8:2 v/v) after repeated washing and recrystallization from methanol and coded Enac1. The pure compound was analyzed using IR, 1H & 13C NMR and GC-MS. Clinical isolates of Escherichia coli, Klebsiella pneumoniae, Salmonella typhi and Staphylococcus aureus were used to assess the antibacterial activity of the pure compound while its preliminary Cytotoxicity was evaluated using brine shrimp nauplii. Based on the spectroscopic data obtained and in comparison with literature, the isolated compound was identified as betulin. The minimum inhibitory concentration (MIC) of betulin ranged between 62.50 - 250.00 µg/mL for all the four bacterial isolates in the study while its fifty percent lethal concentration (LC50) was 10.00 µg/mL. Significant Cytotoxicity with moderate antibacterial activity was observed. The study therefore justifies the existence of bioactive compounds in the stem bark of Entada africana and its use in traditional medicine.


2019 ◽  
Vol 31 (8) ◽  
pp. 1842-1846
Author(s):  
Fatema Tabassum ◽  
Choudhury Mahmood Hasan ◽  
Mohammad Mehedi Masud ◽  
Md. Imran Nur Manik ◽  
Monira Ahsan

Six compounds, sitosta-4-en-3-one (1), 3β,28-dihydroxyolean-12-en (2), scandenone (3), alpinum isoflavone (4), stigmasterol (5) and lupeol (6) were isolated from the methanol soluble extract of the stem bark of Erythrina variegata. The structure of the compounds was established by extensive NMR studies as well as co-TLC with authentic sample. The petroleum ether, carbon tetrachloride, chloroform and aqueous soluble fractions of the methanolic extract of Erythrina variegata were evaluated for antimicrobial, antioxidant and thrombolytic properties. In the antimicrobial study, most of the fractions of the extract exhibited mild to moderate antimicrobial activity where the zone of inhibition were ranging from 7.69 to 19.51 mm. The chloroform soluble fraction showed significant antioxidant activity with IC50 value 66.28 μg/mL as compared to standard BHT (IC50 value 23.09 μg/mL). The thrombolytic property of different extracts of E. variegata exhibited moderate activity ranging from 31.25 to 57.78 %.


Sign in / Sign up

Export Citation Format

Share Document