Plants from the genus Physalis are particularly rich in secondary metabolites. Physalis angulata is a widely distributed annual plant belonging to the nightshade family Solanaceae.
Physalis angulata have been used for centuries as medicinal herbs in the treatment of urinary tract
infection, skin diseases, gonnorhea, ulcers, sores and as vermicidal drug [1,2]. The
main purpose of this present study is to screen the leaves of this plant for phytochemical
constituents that may be responsible for some of these biological activities. The
dried leaves of Physalis angulata were sequentially extracted with dichloromethane and 70% methanol. The aqueous methanol
extract was partitioned between ethyl acetate and n-butanol. From the n-butanol fraction,
four Flavonoids were isolated through column chromatography over silica gel G and
sephadex LH-20. Based on the spectroscopic data which include NMR and mass spectroscopy,
the chemical structures were determined as quercetin (1), quercetin 3-O-methyl ether
(2) isoquercetrin (3) and Kaempferol 7-O-rhamnoside (4). The structures were elucidated
using spectroscopic technique and compared with literature [3 – 4]. Anti-oxidant activity
using DPPH and anti-bacterial activity of the flavonoids were also investigated. These
compounds were isolated for the first time from the leaves of this plant.
Key words:Physalis angulata, flavonoids, quercetin, quercetin methyl ether, isoquercetrin and Kaempferol -7-O-rhamnoside
References:
[1] Choi, EM and Hwang MT. Journ of Ethnopharmacol 89,2003: 171 – 175
[2] Ismail, N and Alam, M. Fitoterapia 72,2001:676 – 679
[3] Mabry, TJ; Markham, KR and Thomas, MB. The Systematic Identification of Flavonoids,
1970,65 – 73,126 – 134
[4] Agrawal, PK. Carbon-13 NMR of Flavonoids, 1983. Elsevier Publication New York,162
– 184
