Exploring biological and chemical properties of Oroxylum indicum (L.) Kurz

M Oliur Rahman; Nahid Sultana; Md Abdur Rashid; Md Abul Hassan

doi:10.21767/2394-9988-C1-003

Exploring biological and chemical properties of Oroxylum indicum (L.) Kurz

EuroScicon Conference on Applied Science, Biofuels & Petroleum Engineering

November 12-13, 2018 Athens, Greece

M Oliur Rahman, Nahid Sultana, Md Abdur Rashid and Md Abul Hassan

University of Dhaka, Bangladesh Jagannath University, Bangladesh

Posters & Accepted Abstracts: Int J Appl Sci Res Rev

Abstract:

The multi-faced biological activities, viz. antioxidant, cytotoxic and antimicrobial potential of methanol extract and its different soluble partitionates of root bark of medicinally important plant Oroxylum indicum were evaluated. In the antioxidant assay by DPPH, free radical scavenging method, crude methanolic extract of root bark of O. indicum revealed the highest free radical scavenging activity with IC50 values of 9.29±0.28 μg/ml. The highest amount of phenolics (15.75±0.34 mg of GAE/gm of extractives) was observed in crude methanolic extract of root bark. The chloroform and dichloromethane soluble fraction of crude extract of root bark of methanolic extract of O. indicum displayed the highest cytotoxic potential having LC50 values of 0.63±0.17 μg/ml and 0.67±0.15 μg/ml respectively. In case of antibacterial screening, dichloromethane soluble fraction of methanolic extract of root bark of O. indicum showed antibacterial activity with the highest zone of inhibition of 16.0 mm observed in Bacillus subtilis. Four compounds were isolated from dichloromethane soluble fraction of methanol extract of root bark of O. indicum and the structure of the purified compounds were elucidated by extensive analysis of their high resolution 1H spectroscopic data as well as by comparison with published values. The isolated compounds were: i) AR-O17 as 5,7-dihydroxy-3- methoxyflavone, ii) AR-O18 as 7-methoxy-3,5 dihydroxyflavone, iii) AR-O23 as 5,7-dihydroxyflavone (Chrysin) and iv) AR-O30 as 3,4',5,7-tetrahydroxyflavonol (Kaempferol). The 1H NMR of AR-017 displayed two sharp singlets at δ 4.05 (3H) and 13.01 (1H). The 13C NMR spectrum of the compound AR-O18 exhibited 13 signals for 16 carbons. The 1H NMR spectrum of the compound AR-O23 demonstrated three sharp singlets at δ 6.24 (1H), 6.49 (1H) and 6.75 (1H), while the 1H NMR (400 MHz, CDCl3) spectrum of AR-O30 presented characteristic signals for a flavonol moiety.