RESUMEN
Ageratum houstonianum, commonly called as bluemink or flossflower, is a predominant weed growing widely in the western Himalaya region. Here, we studied its chemical composition of essential oil (EO), characterization of pure compounds, screening of EO, fractions and pure compounds for their insecticidal activities against larvae of diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) and aphid, Aphis craccivora Koch (Hemiptera :Aphididae).The volatile composition of the EO from above ground parts of A. houstonianum was extracted by steam distillation and characterized by GC and GC–MS analysis. Precocene II (42.16%), precocene I (18.65%) and beta–caryophyllene (15.56%) were the main constituents. Fatty acid composition of the plant was determined using GC–MS after derivatization. The compounds ageratochrome and 1–heptadecene were isolated and characterized using Mass, 1H and 13C NMR spectroscopy. EO, hexane/methanol fractions and isolated compounds were tested against P. xylostella and A. craccivora. Results indicated that EO, hexane fraction, ageratochrome and 1–heptadecene showed more toxicity to larvae of P. xylostella (LC50=2.82, 4.91, 2.15, 4.86 mg/mL, respectively); whereas methanol fraction was more effective against A. craccivora (LC50=1.11 mg/mL) in the residual toxicity assay. The EO also showed repellent activity to P. xylostella (RC50 =2.25 mg/mL).
RESUMEN
ABSTRACT In search of lead molecules for use in disease prevention and as food additive from natural sources, two flavanols were isolated from leaves of Anthocephalus cadamba (Roxb.) Miq., Rubiaceae. Their structures were established as 6-hydroxycoumarin-(4"→8)-(-)-epicatechin and 6-hydroxycoumarin-(4"→8)-(-)-epicatechin-(4→6‴)-(-)-epicatechin on the basis of spectroscopic data. Both the compounds exhibited potent antioxidant and antigenotoxic activity. 6-Hydroxycoumarin-(4"→8)-(-)-epicatechin scavenged DPPH, ABTS+.and superoxide anion radicals with IC50 values of 6.09 µg/ml, 5.95 µg/ml and 42.70 µg/ml respectively whereas the IC50 values for 6-hydroxycoumarin-(4"→8)-(-)-epicatechin-(4→6‴)-(-)-epicatechin were 6.62 µg/ml for DPPH free radicals, 6.93 µg/ml for ABTS radical cations and 49.08 µg/ml for superoxide anion radicals. Both the compounds also exhibited potent reducing potential in reducing power assay and protected the plasmid DNA (pBR322) against the attack of hydroxyl radicals generated by Fenton's reagent in DNA protection assay. In SOS chromotest, 6-hydroxycoumarin-(4"→8)-(-)-epicatechin decreased the induction factor induced by 4NQO (20 µg/ml) and aflatoxin B1 (20 µg/ml) by 31.78% and 65.04% respectively at a concentration of 1000 µg/ml. On the other hand, 6-hydroxycoumarin-(4"→8)-(-)-epicatechin-(4→6‴)-(-)-epicatechin decreased the genotoxicity of these mutagens by 37.11% and 47.05% respectively. It also showed cytotoxicity in COLO-205 cancer cell line with GI50 of 435.71 µg/ml. Both the compounds showed moderate cyclooxygenase-2 inhibitory activity.
RESUMEN
Tinospora cordifolia is used in Ayurveda as "Rasayanas" to improve the immune system and the body resistance against infections. Polysaccharides are the main constituents which are considered to be responsible for immune enhancement. In this study, immunomodulatory activity of three polysaccharide enriched fractions was evaluated using the polymorphonuclear leukocyte function test. Sugar composition was determined by GC-MS analysis of the derivatised fractions. The active polysaccharide fractions mainly constitute glucose, fructose and arabinose as monomer units.
RESUMEN
Picrorhiza kurroa Royle ex Benth., is widely used in the Indian systems of medicine for the treatment of various liver ailments. Since, the role of oxidative stress in the pathogenesis of liver injury has become generally recognized, in present study the free radical scavenging effect of P. kurroa was assessed by on-line HPLC-DPPH and colorimetric DPPH methods. The comparative study on antioxidant activity of P. kurroa extracts by both methods revealed that colorimetric method showed very less free radical scavenging effect while HPLC-DPPH method showed high activity. Further, the kutkoside, an important ingredient of a potent hepatoprotective formulation “kutkin/ picroliv” was investigated for its chemical composition by ultra-performance liquid chromatography coupled with diode array detection/electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-DAD/ESI-QTOF-MS). Kutkoside was considered to be a single compound and reported as picroside-II or kutkoside, however, present investigation illustrated that kutkoside is a mixture of iridoid glycosides namely, picroside II, picroside IV and 6-ferulloylcatalpol.