Ram K. Verma

Isolation of high artemisinin-yielding clones of Artemisia annua

Abstract A random collection of 700 plants of a seed-raised population of Artemisia annua cv. Asha were screened for morphology and artemisinin and essential oil contents. Four morphologically distinct plant types were detected: short and early flowering, tall and early flowering, tall and late flowering, and dwarf and very late flowering. The artemisinin and essential oil were largely present in the inflorescence of all the types of plants. The artemisinin and the essential oil content in the dried herb (inflorescence + leaves) of these plant types ranged from 0.001 to 0.11% and 0.14 to 0.60%, respectively; the late flowering plants were generally richer in both artemisinin and the essential oil. Eleven individual adult plants were selected on the basis of their high artemisinin yield and in vitro regeneration response to a micropropagation procedure using young inflorescence segments as explants. The micro-cloned progenies of the selected plants were tested for their growth, morphology and artemisinin yield and homology in respect to these characters with the respective parent selections. The parent-micropropagated progeny characteristics were observed to be largely congruent. The artemisinin profiles of the micropropagated progenies at vegetative, preflowering and full bloom stages indicated that while highest artemisinin accumulation occurred at full bloom stage, the artemisinin content at preflowering stage was positively correlated with that at full bloom stage. Among the material cloned in vitro and tested in the field, clone numbers 166 and 187 yield 3.2- and 2.5-fold more artemisinin per plant as compared to the parent cultivar Asha, the former due to high herb yield and latter due to high artemisinin content per se.

Lipid constituents of Tridax procumbens

Abstract Eight new compounds, isolated from Tridax procumbens , have been characterized as methyl 14-oxooctadecanoate, methyl 14-oxononacosanoate, 3-methylnonadecylbenzene, heptacosanyl cyclohexane car☐ylate, 1(2,2-dimethyl-3-hydroxypropyl)-2-isobutyl phthalate, 12-hydroxytetracosan- 15-one, 32-methyl-30-oxotetratriacont-31-en-1-ol and 30-methyl-28-oxodotriacont-29-en-1-oic acid by spectral data and chemical studies. Nine known compounds isolated for the first time from the plant, were identified as dotriacontanol, β-amyrone, Δ 12 -dehydrolupen-3-one, β-amyrin, lupeol, fucosterol, 9-oxoheptadecane, 10-oxononadecane and sitosterol. Although Δ 12 -dehydrolupen-3-one is reported synthetically, this is the first report of this compound from a natural source.

In vivo anti-diabetic activity of derivatives of isoliquiritigenin and liquiritigenin

Isoliquiritigenin (ISL), a chalcone and liquiritigenin (LTG), a flavonoid found in licorice roots and several other plants. ISL displays antioxidant, anti-inflammatory, antitumor and hepatoprotective activities whereas LTG is an estrogenic compound, acts as an agonist selective for the β-subtype of the oestrogen receptor. Both the phenolics were isolated from the rhizomes of Glycyrrhiza glabra. Five derivatives from ISL and four derivatives from LTG were synthesized. All the compounds were established by extensive spectroscopic analyses and screened through oral glucose tolerance test to gain preliminary information regarding the antihyperglycemic effect in normal Swiss albino male mice. ISL (1), ISL derivatives 3, 4, 5, 7 and LTG derivatives 9 and 10 showed significant blood glucose lowering effect. The structure-activity relationship indicated that the presence of ether and ester groups in ISL and LTG analogues are important for exhibiting the activity. Compounds 1, 4 and 10 were selected for in vivo antidiabetic activity and found to be potential candidates for treatment of diabetes. It is the first report on antidiabetic activity of ISL derivative 4 and LTG derivative 10.

Determination of plumbagin by normal-phase high-performance liquid chromatography

Abstract A simple and rapid normal-phase high-performance liquid chromatographic method for the determination of a pharmacologically important 1,4-naphthoquinone, plumbagin, and a chromene, 2,2-dimethyl-5-hydroxy-6-acetylchromene, in plant extracts was developed. Both compounds were well resolved with maximum recovery (97%) on a μSpherogel column using n -hexane-chloroform-2-propanol (30:70:2) as the mobile phase.

HPLC DETERMINATION OF VASICINE AND VASICINONE IN ADHATODA VASICA WITH PHOTO DIODE ARRAY DETECTION

A high performance liquid chromatographic method for the determination of the quinazoline alkaloids vasicine (1) and vasicinone (2) in Adhatoda vasica plant extract is reported. Peak purity and similarity of 1 and 2 have been studied using photodiode array detector (PDA). Effects of different solvents have been studied for the extraction of 1 and 2 in A. vasica plant, and methanol was found to give the maximum extraction of compounds 1 and 2. The method is simple, sensitive, rapid, and reproducible for the quantitation of pharmacologically important alkaloids vasicine and vasicinone. The separation of 1 and 2 was performed with acetonitrile–phosphate buffer (pH maintained to 3.9 using glacial acetic acid) (15:85) using a Hibar Merck make C18 column.

Lipid constituents of Cissus quadrangularis

Abstract Seven new compounds, isolated from Cissus quadrangularis, have been characterized as 4-hydroxy-2-methyl-tricos-2-en-22-one, 9-methyl-octadec-9-ene, heptadecyl octadecanoate, icosanyl icosanoate, 31-methyl-tritriacontan-1-ol, 7-hydroxy-20-oxo-docosanyl cyclohexane and 31-methyltritriacontanoic acid. Taraxeryl acetate, friedelan-3-one, taraxerol and iso-pentacosanoic acid were also isolated for the first time from this plant.

4α-Methyl-24β-ethyl-5α-cholesta-14,25-dien-3β-ol and 24β-ethylcholesta-5, 9(11), 22E-trien-3β-ol, sterols from Clerodendrum inerme

From the aerial parts of Clerodendrum inerme, two new sterols (4alpha-methyl-24beta-ethyl-5alpha-cholesta-14, 25-dien-3beta-ol and 24beta-ethylcholesta-5, 9(11), 22E-trien-3beta-ol) and a new aliphatic ketone (11-pentacosanone) were isolated together with another known aliphatic ketone (6-nonacosanone) and a diterpene (clerodermic acid). The structure elucidations were based on analyses of physical and spectroscopic data.

Terpenoids from Hemidesmus indicus

Abstract The hexane soluble portion of the ethanol extract of the stem of Hemidesmus indicus afforded a new triterpene lactone, characterized as 3-keto-lup-12-ene-21→28-olide. Further, lupanone, Δ 12 -dehydrolupanyl-3β-acetate, Δ 12 -dehydrolupeol acetate, hexadecanoic acid, 4-hydroxy-3-methoxybenzaldehyde, 3-hydroxy-4-methoxybenzaldehyde were also isolated for the first time from this plant.

Unsymmetric tetracyclic triterpenoid from Cissus quadrangularis.

Abstract A new unsymmetrical tetracyclic triterpenoid, 7-oxoonocer-8-ene-3β,21α-diol, has been isolated from Cissus quadrangulars . The structure was elucidated on the basis of spectral and chemical evidences.

Oxo acids and branched fatty acid esters from rhizomes of Costus speciosus

Five new compounds, isolated from the rhizomes of Costus speciosus have been characterized as tetradecyl 13-methylpentadecanoate, tetradecyl 11-methyltridecanoate, 14--oxotricosanoic acid, 14-oxoheptacosanoic acid and 15-oxo-octacosanoic acid by spectral and chemical studies. Triacontanol, 5α-stigmast-9(11)-en-3β-ol, triacontanoic acid, sitosterol and diosgenin have also been isolated and identified.