Jw Mwangi

Epoxychiromodine and other constituents of Croton megalocarpus

Abstract A novel clerodane-type diterpene with a 6,7-oxirane group has been isolated from Croton megalocarpus. Structure elucidation has been achieved by a combination of spectroscopic measurements including 2D NMR and NOE experiments. In addition, 3-O-acetoacetyl lupeol, a novel triterpene ester, the triterpene O-acetyl aleuritolic acid, and long chain esters of E-ferulic acid with C24-, C26- and C28-alcohols were also isolated and characterized by spectroscopic methods.

Constituents of the Essential Oil of Helichrysum odoratissimum (L.) Less

ABSTRACT The essential oil of the flowers of Helichrysum odoratissimum (L.) Less. growing wild in Kenya was analyzed by GC and GC/MS. Nineteen compounds were identified, the major constituents being α-pinene (43.4%), (E, E)-farnesol (16.8%) and α-humulene (14.6%).

Pharmacological activity of Oxalis corniculata

A methanol extract of O. corniculata showed relaxant activity on isolated rabbit ileum which was dose-dependent. The plant extract also showed cardiorelaxant activity on isolated rabbit heart. In anaesthetised rats, a fall in diastolic pressure, with a lesser fall in systolic pressure, was observed.

Essential oil of cymbopogon winterianus jowitt from Tanzania: Composition and antimicrobial activity

Abstract The hydro-distilled essential oil (1.6%) of fresh aerial parts of wild Cymbopogon winterianus Jowitt was analyzed by GC-MS. Fifty compounds representing 96.5% of the oil were identified. The main components of the oil were linalool (27.4%), citronellol (10.9%), geraniol (8.5%), α-calacorene, cis-calamenene (4.3%), β-elemene (3.9%) and longifolene (3.5%). The oil exhibited low antimicrobial activity.

Essential oil constituents of artemisia afra willd

ABSTRACT The essential oil isolated from leaves of Artemisia afra Willd. (1.5%) by hydrodistillation was analyzed by GC and GC/MS. Fifty compounds constituting about 93% of the oil were identified. The major constituents were 1,8-cineole (67.4%), terpinen-4-ol (6.5%) and borneol (5.1%).

Proteomic and histological analyses of endosperm development in Cyclamen persicum as a basis for optimization of somatic embryogenesis

The endosperm plays an important role for the development of zygotic embryos, while somatic embryos lack a seed coat and endosperm and often show physiological disorders. This study aims at elucidating the cellular and physiological processes within the endosperm of the ornamental species Cyclamen persicum Mill. Histological analyses were performed from 0 to 11 weeks after pollination (WAP). At 3WAP, a syncytium was clearly visible with a globular zygotic embryo. From 4WAP, cellularization of the endosperm, at 5WAP a small torpedo shaped embryo, and from 7WAP cell expansion was observed. By 11WAP the endosperm appeared fully differentiated. Total soluble proteins were extracted from the endosperm at 4, 5, 7, 9 and 11WAP and resolved using two dimensional isoelectric focussing/sodium dodecyl sulphate-polyacrylamide gel electrophoresis (2D IEF/SDS-PAGE). A shift from high-molecular-mass proteins to low-molecular-mass proteins during endosperm development was observed. A total of 1137proteinspots/gel were detected in the three protein fractions extracted at 7, 9 and 11WAP. Mass spectrometry analysis of the 48 predominant protein spots in endosperm at 7, 9 and 11WAP resulted in the identification of 62 proteins, ten of which were described for the first time in Cyclamen. Additionally, 186 proteins were identified using the C. persicum embryo proteome reference map. Proteins involved in abscisic acid signalling and oxidative stress responsive proteins were found to be important for seed development in Cyclamen. The new insights into endosperm physiology including storage compounds are discussed.

Pharmacological Activities of Gardenia jovis-tonantis

A methanol extract derived from Gardenia jovis-tonantis showed bronchodilator activity on isolated guinea pig trachea. The extract also showed cardiorelaxant activity on isolated rabbit heart and caused a rapid fall in diastolic pressure in anaesthetised rats.

Volatile constituents of essential oil of Tarconanthus camphoratus L

ABSTRACT The leaf oil of Tarconanthus camphoratus (Compositae) was analyzed by GC and GC/MS. Sixty compounds representing ca. 95% of the oil were identified. The major components were α-fencyl alcohol (29.1%), 1,8-cineole (16.5%) and α-terpineol (8.5%).

Effects of the active constituents of Catha edulis on the neuromuscular junction

(-)-Cathinone and d-norpseudoephedrine (DNE) in the dose range 0.2-1.2 mg/ml produced a reduction in contractions of skeletal muscle, evoked by direct and indirect electrical stimulation and antagonised the facilitatory action of physostigmine on the neuromuscular junction; but failed to antagonise a partial blockade induced by d-tubocurarine (dTb) as occurs with norepinephrine or epinephrine. The local anaesthetic actions of (-)-cathinone and DNE were found to be almost equivalent to that of lignocaine. These results indicate that (-)-cathinone and DNE may have a direct blocking action on the neuromuscular junction, which is independent of cholinergic and adrenergic transmission.

Effect of the tuber of adenia globosa on isolated rat uterus preparation

The effect of the tuber aqueous extract of Adenia globosa Engl. (Passifloraceae) on the isolated rat uterus was determined. The extract caused a dose-dependent contraction of the uterus. This activity would explain the traditional usage of this plant in hastening parturition in domestic animals.