Evaluation of phytochemical and antimicrobial properties of leaf extract of Tapinanthus sessilifolius (P. Beauv) van Tiegh.

Leaf extracts of T. sessilifolius growing on five different host plants (Psidium guajava, Citrus lemon, Vernonia amygdalina, Persea americana and Jatropa curcas) were evaluated for antimicrobial activity of the plant. Powdered leaves of T. sessilifolius collected from each host plant was divided into two portions. One portion was used for aqueous infusion and the other portion was successively extracted with hexane, ethylacetate and methanol. Infusion of aqueous extract of powdered leaves did not show antimicrobial effect even at the concentration of 1000 and 2000 microg/ml on test microorganisms (Staph. aureus, E. coli, Bacillus subtilis, Pseudomonas aeruginosa and Candida albicans). However in broth culture, methanolic and hexane extract had MIC range of 62.5-500 microg/ml and ethylacetate extract had 250-500 microg/ml. Phytochemical screening of leaf samples of T. sessilifolius collected from different host plants showed positive test for hydrolysable tannins, saponins, flavonoids, terpenes, cardiac glycoside, reducing sugars and proteins. LD50 concentration was found to be > 1.500 mg/kg for samples from P. guajava; 489.89 mg/kg for J. curcas and C. lemon; and 692 mg/kg for V. amydalina in mice.

Effect of the aqueous extract of African mistletoe, Tapinanthus sessilifolius (P. Beauv) van Tiegh leaf on gastrointestinal muscle activity.

Effects of the aqueous extract of T. sessilifolius on the gastrointestinal muscle were investigated on smooth muscle preparations isolated from rabbit jejunum, guinea pig ileum and on gastrointestinal transit in mice. Elemental analysis of the extract was also carried out. The aqueous extract of T. sessilifolius evoked a concentration dependent contraction of the rabbit jejunum and guinea pig ileum. The contractions evoked by the extract were not attenuated either by atropine or mepyramine, but they were completely blocked by verapamil. The elemental analysis revealed the presence of Mg, Zn, Fe, Cu, and very high concentration of Ca. The intraperitoneal LD50 in mice was found to be 1500 mg/kg. The aqueous extract of T. sessilifoliius possesses active components that may be mediating the observed biological activity through calcium mobilization.

Anti-diabetic properties of the African mistletoe in streptozotocin-induced diabetic rats.

The African mistletoe, Loranthus bengwensis L. (Loranthaceae), has been widely used in Nigerian folk medicine to treat diabetes mellitus. The aqueous extract or infusion (1.32 g/kg per day) of the leaves of this plant parasitic on lemon, Citrus limon (L.) Brum f. (Rutaceae), guava, Psidium guajava L. (Myrtaceae) and jatropha, Jatropha curcas L. (Euphorbiaceae), respectively, were supplied ad libitum to separate groups of both non-diabetic and streptozotocin-induced diabetic rats, as their only source of fluid for a period of 28 days. The infusions of mistletoe parasite on both lemon and guava trees significantly decreased serum glucose levels in non-diabetic (P < 0.05) and diabetic (P < 0.001) rats, whereas that prepared from mistletoe parasitic on jatropha did not. The data indicate that African mistletoe possesses significant anti-diabetic activity in streptozotocin-induced diabetic rats; its anti-diabetic activity appears to be highly dependent on the host plant species.

Globulines anormalment precipitables (GAP) in Nigerian users of progestogen-only pill.

The globulines anormalment precipitables (GAP), which have been reported to be raised in current and former oral contraceptive users, were measured in Nigerian subjects which included male volunteers. The results showed that GAP were present in males who had never used contraceptives and that the mean values were lowest in intrauterine contraceptive device (IUD) users and highest in females who had never used any contraceptives. However, current contraceptive users had lower mean GAP values than either former users or never users. It was therefore concluded that GAP levels alone cannot be used to predict the development of thromboembolic complications in pill users, and that ethinyl estradiol cannot be the main physiological stimulus for GAP synthesis.

Elevated abnormal proteins in the serum of Nigerian pill users.

The 'globulines anormalment precipitables' (GAP) which have been reported to be raised in current and former oral contraceptive users was measured in Nigerian subjects (which) including male volunteers. The results showed that GAP were present in males who had never used contraceptives and that the mean values were the lowest in intrauterine contraceptive (IUD) users and highest in females who had never used any contraceptive. However, current contraceptive users had lower mean GAP values than either former users or never users. Therefore it has been concluded that GAP levels alone cannot be used to predict the development of thrombo-embolic complications in pill users, and that ethinyl oestradiol cannot be the main physiological stimulus for GAP synthesis.

PIP: Researchers obtained serum samples from 182 healthy men and women living in Jos, Plateau State in Nigeria after fasting to measure abnormal protein (globulins anormalement precipitables [GAP]) levels. Specifically, they wanted to compare the levels of the 5 groups: 30 women who had never used oral contraceptives (OCs), 38 males, 48 women using progesterone only OCs, 32 women who used OCs for 2 years and stopped 6 months before this study, and 34 women using a copper releasing IUD. Former OC users had the highest mean GAP levels (1336.37 mcg/ml). Further the mean GAP levels for males (932.25 mcg/ml) was significantly higher than women using IUDs (p.05). Indeed significant differences existed between all groups (p.05). A more pronounced difference in pattern and magnitude of GAP values for control and experimental groups occurred among these Nigerians than in previous studies involving Whites. Further results of 1 study revealed European Blacks to have a significantly higher GAP level than Whites. Therefore the higher GAP levels in Blacks may be more dependent on genetic factors than dietary factors. Another important finding of this study was the possible role of progesterone only OCs in reducing GAP levels beyond normal physiological limits. In addition, this study suggested that, contrary to earlier belief, ethinyl estradiol may not be the main stimulus for GAP production since men had relatively high levels of GAP. In conclusion, health practitioners should not use GAP levels alone to predict the development of thrombosis in OC users.