Oral micro-organisms play a significant role in mouth disease. The aim of this work was to evaluate the antimicrobial potency of four essential oils against seven bacterial species isolated from patients sickly of oral infections. Bacterial species were isolated and identified from patient sample during a prospective study at the Yaounde University Teaching Hospital Centre. The essential oils were analysed simultaneously by Gas Chromatography and Gas Chromatography / Mass Spectrophotometry. Agar disk diffusion and microdilution methods were used to assay the antibacterial activity. The highest inhibition zone was recorded against Staphylococcus aureus (43.5 ± 3.17) for Pentadiplandra brazzeana. The highest minimum inhibitory concentration (0.078mg/mL) values were detected for Klebsiella pneumonia and minimal bactericidal concentration (0.078 mg/mL) values were detected for Eugenia caryophylla. The active essential oils contained mainly hydrocarnated and oxygenated monoterpens. Active essential oils represent a potential source of antibacterial substances in mouthwash and dentifrice.

The present study evaluated in vitro antioxidant activity, cytotoxicity and genotoxicity of aqueous extracts from Antocleista schweinfurthii. Polyphenols content was determined by the Folin Ciocalteu method. The antioxidant activities were evaluated using ABTS and β-carotene assays. Cytotoxicity was investigated by the MTT method while genotoxicity was ascertained using the Salmonella typhimurium test strains TA98 and TA100. Standard methods were used for phytochemical screening. The aqueous extract of the bark is rich in total polyphenols of 985±32 mg EAA/g of dry weight. Aqueous extract of Anthcleista schweinfurthii barks had a high antiradical activity with IC_(50 )of 153±3µg/mL and high reducing activity with IC_(50 )of 2.3±0.12 µg/mL. Toxicity study indicated that all extracts are cytotoxic and non genotoxic. Phytochemical screening revealed the presence of alkaloids, saponins and flavonoids in both extracts. Lack relatively toxicity suggest that this plant is probably safe for use, however futher studies are needed for longer.

Oral route is the most common route for administration of solid dosage form, about 85% of solid dosage administered by oral route. Disintegration plays major role in improving the drug activity. Disintegrants are substances added to the drug formulation that increase the breakup of the tablet or capsule into smaller particles in aqueous environment that dissolve more rapidly than in the absence of disintegrants. Nowadays some newer agents have been developed known as Superdisintegrants. Superdisintegrants are the substances, which facilitate the faster disintegration with smaller quantity in contrast to disintegrants. These are of two type’s natural and synthetic superdisintegrants. Superdisintegrants are generally used at a low level in the solid dosage form, typically 1- 10% by weight relative to the total weight of the dosage unit. These are used to improve the efficacy of solid dosage form. Examples of superdisintegrants are sodium starch glycolate, crospovidone, Gellan gum etc.

Herbal traditional plants are considered as resources of ingredients which can be used in drug development pharmacopoeial, non- pharmacopoeial or many types of synthetic drugs. Polyalthia longifolia is used by tribal people for treatment of diabetes. The aim of present study was to evaluate the potency of antdiabetic activity of leaves extract. The P. longifolia leaf extract was administered orally in Streptozotocin (STZ)-induced diabetic rats. When the extract was administrated, blood glucose levels were monitored at specific intervals and it was found that they were significant lowered. The effect of P. longifolia on induced hyperlipidemia was analyzed where the significantly lowered the elevated total cholesterol, triglycerides (TGL) and low density lipoprotein (LDL) level while increased the High density lipoprotein (HDL). Standard drug glibenclamide was used at a dose of 0.50 mg/kg body weight. Moreover, the extract treated rats exhibited the significant rise in serum insulin level compared with streptozotocin- induced diabetic rats. The present results showed that extract isolated from Polyalthia longifolia has significant antidiabetic activity in streptozotocin-induced rats compared to standard drug.

Oral bioavailability is the major problem when a poorly water-soluble drug is delivered via oral route. Solid dispersion systems have been demonstrated to overcome such problems and to enhance the dissolution rate of poorly water-soluble drugs. In the present review, the important points to be considered during formulation of solid dispersion systems viz., preparation methods of solid dispersion which affect on the dissolution rate of the drug as well as its formulation and evaluation techniques have been described.