Raushanara Akter

HPLC-Analysis of Polyphenolic Compounds in Gardenia jasminoides and Determination of Antioxidant Activity by Using Free Radical Scavenging Assays

PURPOSE Gardenia jasminoides is a traditional medicinal plant rich in anti-inflammatory flavonoids and phenolic compounds and used for the treatment of inflammatory diseases and pain. In this present study, antioxidant potential of Gardenia jasminoides leaves extract was evaluated by using various antioxidant assays. METHODS Various antioxidant assays such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, reducing power and total antioxidant capacity expressed as equivalent to ascorbic acid were employed. Moreover, phenolic compounds were detected by high-performance liquid chromatography (HPLC) coupled with diode-array detection. RESULTS The methanol extract showed significant free radical scavenging activities in DPPH radical scavenging antioxidant assays compared to the reference antioxidant ascorbic acid. Total antioxidant activity was increased in a dose dependent manner. The extract also showed strong reducing power. The total phenolic content was determined as 190.97 mg/g of gallic acid equivalent. HPLC coupled with diode-array detection was used to identify and quantify the phenolic compounds in the extracts. Gallic acid, (+)-catechin, rutin hydrate and quercetin have been identified in the plant extracts. Among the phenolic compounds, catechin and rutin hydrate are present predominantly in the extract. The accuracy and precision of the presented method were corroborated by low intra- and inter-day variations in quantitative results in leaves extract. CONCLUSION These results suggest that phenolic compounds and flavonoids might contribute to high antioxidant activities of Gardenia jasminoides leaves.

Antidiarrhoeal property of the hydroethanolic extract of the flowering tops of Anthocephalus cadamba

The antidiarrhoeal property of the hydroethanolic extract of the flowering tops of Anthocephalus cadamba was assessed on experimental animals. The dry hydroethanolic extract (250-500 mg/kg body mass, p.o.) exhibited a dose-dependent decrease in the total number of faecal droppings in castor oil-induced diarrhoea in mice. The extract also produced a significant (p < 0.01) and dose-dependent reduction in intestinal fluids accumulation and in the gastrointestinal transit from 64.59 % and 71.19% at doses of 250 and 500 mg/kg. The reduction rates were 37.85% and 74.91%, respectively, with the control and standard drug group.

A new cytotoxic diterpenoid glycoside from the leaves of Blumea lacera and its effects on apoptosis and cell cycle

Abstract A new diterpenoid glycoside, 6E,10E,14Z-(3S)-17-hydroxygeranyllinalool-17-O-β-d-glucopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (1) together with the known diterpenoid glycoside (2) and two known flavonoid glycosides (3, 4) were isolated from the methanol extract of Blumea lacera leaves. The structures were determined by the interpretation of their spectroscopic data and comparison with the literature. All compounds were isolated for the first time from B. lacera and evaluated for their cytotoxic activity. Only the new compound (1) showed strong cytotoxic activity with the lowest IC50 value (8.3 μM) being displayed against MCF-7 breast cancer cells. In apoptosis and cell cycle analysis, 1 revealed strong apoptotic activity against MCF-7 cells (45.5% AV+/PI−) after 24 h, but showed no arresting of any of the cell cycle phases in MCF-7.

In vitro anti-oxidant activity of the leaves of Dillenia indica

SUMMARY The methanol extract of Dillenia indica was tested for antioxidant activity as determined by free radicalscavenging of DPPH radical scavenging assay, reducing power, total antioxidant capacity measuredby phosphomolybdenum method, total phenolic content and total flavonoids content determinationassays. The extract showed significant activities in all antioxidant assays compared to the standardantioxidant in a dose dependent manner. In DPPH radical scavenging assay the IC 50 value of theextract was found to be 100.53 µg/ml while ascorbic acid has the IC 50 value 58.92 µg/ml. Dillenia indicaextract showed strong reducing power and total antioxidant capacity. Moreover, methanol extractsalso possess high amount of phenolics and flavovonoids and expressed as gallic acid and rutinequivalent respectively. The remarkable activities exhibited in reactive oxygen species scavengingmay attributed to the high amount of hydrophilic phenolics present in Dillenia indica.Key words: Dillenia indica; DPPH; Total antioxidant capacity; Reactive oxygen species

Antinociceptive and gastro-protective effect of the ethanolic extract of the flowering top of Anthocephalus Cadamba Roxb

The effect of alcoholic extract of Anthocephalus (A.) Cadamba Roxb. was evaluated in experimental models of pain and ulcer. Hot tail flick test, hot plate test and acetic acid induced writhing test were employed for evaluating the peripheral as well as central analgesic mechanism exerted by the extracts. Gastroprotective activity was examined by HCl and ethanol induced gastric damage test. Test group received crude extract 500 mg/kg showed maximum time needed for the response against thermal stimuli (6.26 ± 0.439 s) which is comparable to diclofenac sodium (6.56 ± 0.381 s) in hot tail flick method. These experimental results also followed the experimental results of hot plate test where crude extract 500 mg/kg showed maximum time needed for the response against thermal stimuli (4.74 ± 0.234 s) which is comparable to diclofenac sodium (5.58 ± 0.585 s). The crude extract at 500 and 250 mg/kg showed significant reduction in acetic acid induced writhing in mice with a maximum effect of 68.026% reduction at 500 mg/kg dose which is comparable to standard diclofenac sodium (79.93%). In gastroprotective study the extract of A. Cadamba (250 and 500 mg/kg) significantly inhibited ulceration induced by both HCl and ethanol dose dependently. Results of the study suggest that the extract possesses both analgesic and gastroprotective activity on mice.