Anti-Respiratory Syncytial Virus Compounds from Two Endophytic Fungi Isolated from Nigerian Medicinal Plants.

Background: Respiratory syncytial virus (RSV) is known to cause severe respiratory infections particularly in infants younger than 2 years of age. The only approved drug, ribavirin, is expensive and is not likely to improve therapeutic outcome, thereby necessitating the search for safer and more potent alternatives from natural sources such as endophytic fungi. The present study aimed to investigate the anti-RSV activity of compounds from endophytic fungi. Methods: Two endophytic fungi Colletotrichum gloeosporioides and Pestalotiopsis thea were isolated from the fresh leaves of the host Nigerian plants Anthocleista djalonensis and Fagara zanthoxyloides, respectively. After fermentation in solid rice media, C. gloeosporioides afforded 4 known compounds 4-hydroxybenzoic acid (1), vanillic acid (2), ferulic acid (3) and Nb-acetyltryptamine (4) while P. thea afforded 3 known compounds chloroisosulochrin (5), ficipyrone A (6) and pestheic acid (7). The compounds were investigated for their anti-RSV activity using the HEP-2 cell lines and ribavirin as the standard drug. Results: Compound 5 was found to show the strongest inhibition of the RSV with IC50 of 4.22±1.03 µM (ribavirin 4.91±1.85 µM). Other compounds showed moderate inhibition of the virus (IC50 ranging from 45.00±0.98 to 259.23±2.36 µM). Conclusion: The results of the present study have shown that chloroisosulochrin (5), isolated from an endophytic fungus P. thea, possesses strong activity against RSV.

Topical anti-inflammatory constituents of lipophilic leaf fractions of Alchornea floribunda and Alchornea cordifolia.

The leaves of Alchornea floribunda and Alchornea cordifolia are used traditionally as topical anti-inflammatory agents. In this study, two highly lipophilic fractions AFLF and ACLF isolated from A. floribunda and A. cordifolia leaves respectively were investigated for topical anti-inflammatory effects using xylene-induced mice ear oedema as a model of inflammation. AFLF and ACLF at 5 mg per ear showed significant (p < 0.01) topical anti-inflammatory effect with oedema inhibitions of 64.0% and 79.0% at 2 h, respectively. When compared to indomethacin (5 mg per ear), these fractions showed significantly (p < 0.05) higher topical anti-inflammatory effect. Gas chromatography-mass spectrometry analysis revealed that AFLF is composed mainly of long chain saturated and unsaturated hydrocarbons (18.78%) and their oxygenated derivatives (1.89%); while ACLF is rich in volatile oils eugenol (21.26%) and cadinol (4.76%), and other constituents like, nanocosaine (36.86%) and steroid derivatives, ethyl iso-allocholate (4.59%) and 3-acetoxy-7,8-epoxylanostan-1-ol (15.86%). Analysis of the volatile oil (ACV) extracted from the fresh leaves of A. cordifolia revealed the presence of high concentrations of eugenol (41.7%), cadinol (2.46%), Caryophylene (1.04%), Linalool (30.59%) and (E)-α-bergamotene (4.54%). These compounds could be contributing to the topical anti-inflammatory effects of A. floribunda and A. cordifolia leaf extracts.

A new anti-inflammatory flavonol glycoside from Alchornea floribunda leaves.

Alchornea floribunda leaves are widely used in African ethnomedicine for the management of acute and chronic inflammatory disorders. In the present study, bioactivity-guided fractionation of the ethyl acetate fraction of the methanol leaf extract of the plant material led to the isolation of a new flavonol glycoside (AFF1). The anti-inflammatory activity of this novel compound was evaluated using egg albumen-induced rat paw oedema as a model of inflammation. AFF1 showed significant inhibition of the rat paw oedema in a dose-dependent manner. The activity of AFF1 (50 mg kg(-1)) was higher than that of the standard anti-inflammatory drug, aspirin (100 mg kg(-1)). The compound also significantly (p < 0.001) inhibited heat-induced haemolysis of human erythrocytes in vitro. The structure of AFF1 was elucidated as 3,5,7,3'-tetrahydroxyflavone-3-O-alpha-L-rhamnoside, using a combination of UV, IR, 1D and 2D (COSY) 1H-NMR spectroscopy. This compound, in part, accounts for the anti-inflammatory effect of A. floribunda leaves.

In vitro and in vivo evaluation of the antitrypanosomal activity of fractions of Holarrhena africana.

The aqueous extract of young leaves of Holarrhena africana, a plant used in the Nigerian traditional medicine, exhibited good activity against Trypanosoma brucei spp. The extract was fractionated and eight fractions were obtained. One fraction designated as HaF(5) showed in vitro activity against Trypanosoma brucei rhodesiense with an IC(50) value of 0.785 microg/mg and no overt cytotoxicity against L-6 cells. Fraction HaF(5) was tested in vivo at two doses and found to exhibit in vivo efficacy in Trypanosoma brucei brucei infected mice leading to a complete disappearance of parasitaemia followed by a relapse.

Antimicrobial activity of Loranthus micranthus harvested from kola nut tree.

Various solvent extracts of Loranthus micranthus exhibited varying degrees of antimicrobial activity. Only the petroleum ether extract showed antifungal activity. The methanol extract showed the best antimicrobial activity against Escherichia coli and Bacillus subtilis.

Haematotoxic evaluation of crude cannabis resin in rats

After chronic administration of crude Cannabisresin (CCR); (20 mg/kg and 40 mg/kg) to Spraque-Dawley albino rats for 21 days; the changes in various haematological indices such as packed cell volume (PVC); total leukocyte count; differential leukocyte count; red blood cell (RBC) count; absolute lymphocyte count; monocyte count; neutrophils and eosinophil counts were evaluated. The results show that the haematological indices such as erythrocytic and leucocytic counts were not significantly (P 0.05) affected by the treatment with the crude cannabinoid resin treated animal groups for the first two weeks of treatment. However in the third week; results showed significant increases (P 0.05) in the above mentioned indices while eosinophils disappeared from the blood of treated groups. It can be concluded from this study that chronic administration of CCR at high doses (above 20mg/Kg) to rats has slight haematotoxic potentials

Chromatographic and anti-motility studies on extracts of loranthus micranthus linn

The anti-motility properties of the leaves of African mistletoe; Loranthus micranthus (Linn); Loranthaceae harvested from Kola acuminatahost tree was studied by the charcoal meal test in mice. The intraperitoneal LD50 of the methanol extract was determined in mice by the Locke's method. The phytochemical constituents of the leaf extract were also determined. An attempt was also made to resolve the extracts into its components using thin layer chromatography (TLC). The leaves of L. micranthus were found to contain alkaloids; cyanogenetic glycosides; saponins; flavonoids; tannins; proteins and resins. The intraperitoneal LD50 of the methanol extract of the leaves in mice was calculated to be 5916 mg/kg. Among the chromatographic solvent systems tested; toluene: diethylamine (19:1) gave the best resolution in all the extracts. The highest number of spots was obtained with the ethanol extract. Result of the charcoal meal test revealed that the methanol extract had a significant dose-dependent anti-motility effect. At a dose of 200 mg/kg; the methanol extract produced a decrease in gastric transit time; which was significantly (P 0.05) higher than that of atropine (10 mg/kg)

Study on anti-diabetic activities of crude methanolic extracts of Loranthus micranthus (Linn.) sourced from five different host trees.

The hypoglycaemic and anti-hyperglycemic activities of dried leaves of Loranthus micranthus (Linn.) (Loranthaceae), parasitic on Persea americana, Baphia nitda, Kola acuminata, Pentaclethra macrophylla, Azadirchta indica, were evaluated in normoglycemic and alloxan-induced diabetic albino rats. Normoglycemic and alloxan-induced diabetic rats were treated (intraperitoneally) with 200 mg/kg of the respective methanolic extracts of Loranthus micranthus (Linn.), glibenclamide (positive control), and 20% (v/v) Tween 20 solution (negative control). The sugar levels of the withdrawn blood samples were determined by o-toluidine spectrophotometric method. The studies indicate that the crude methanolic extract of Loranthus micranthus (Linn.) exhibited statistically significant hypoglycaemic (P < 0.001) and anti-hyperglycemic (P < 0.001) activities in normoglycemic and alloxan-induced diabetic albino rats, respectively. The hypoglycaemic effect was found to be dose-dependent. The maximum effect of the mistletoe extract (400 mg/kg) from Persea americana on alloxan-induced diabetic rats was found to be statistically comparable with that of the positive control, glibenclamide, at 24 h after administration, with a percentage reduction of blood sugar levels of 82.59 and 83.34%, respectively. Acute toxicity tests of the methanolic extracts of Persea americana, Baphia nitda, Kola acuminata, Pentaclethra macrophylla, Azadirchta indica host trees in mice gave LD(50) values of 11650, 11650, 5900, 5900 and 5900 mg/kg, respectively, which are all within the practically non-toxic range. The methanolic extract of African mistletoe was found to be a good candidate for alternative and/or complimentary medicine in the management of diabetes mellitus. The leaves of the Eastern Nigerian species of the African mistletoe harvested from Kola acuminata, Azadirchta indica and Baphia nitda host trees exhibited comparatively better anti-hyperglycemic activities among the host trees studied.

Assessment of quality control parameters and interchangeability of multisourced metformin HCl tablets marketed in Nigeria.

A quality control assessment of five brands of metformin hydrochloride tablets marketed in Nigeria [Glucophage (R) (Merck, Quetta), Metformin BDC (Bangkok labs, Bangkok), Metformin (Medopharm, India), Glucophage (R) (Ilsan), Glucophage (Lipha)] was carried out in order to determine the brands that are interchangeable or switchable. The disintegration time, dissolution rate and absolute drug content were determined in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) without enzymes. The weight uniformity and hardness tests were also performed according to the official methods. A variation of the concept of dissolution efficiency (DE), known as predicted availability equivalent (PAE), was used to predict the likely in vivo bioavailability. Our results showed that all the five brands passed the uniformity of weight and disintegration tests. Dissolution efficiency was found to be higher in SGF than in SIF. In SGF, all the brands were bioequivalent. In SIF, all the brands, except Medopharm, were also bioequivalent. The study showed that four brands of metformin hydrochloride (Merck, BDC, Lipha and Ilsan) marketed in Nigeria are of acceptable standards and hence BDC, Lipha and Ilsan brands of glucophage are interchangeable with the innovator drug, glucophage R (Merck).

Structure-activity relationship studies: study of the analgesic properties of a series of synthesized esters of 3- (4-benzyl-1-piperazinyl) 1-phenylpropanols.

Four previously stynthesized derivatives of 3- (4-benzyl-1-piperazinyl)-1-phenylpropanol were screened for analgesic activity in albino mice using a variation of the Eddy and Lambach hot plate method. The result showed that the most significant analgesic effect was elicited by the parent secondary 3-piperazinylpropanol, namely 3-(4-benzyl-1-piperazinyl)-1-phenylpropanol. Its esterification products with propanoyl, benzoyl and phenylacetyl chlorides exhibited reduced analgesic properties. The percent maximum protection against thermal pain produced by Aspirin (71.43%) was twice as high as that produced by the most active of the four derivatives (43.65%). The analgesic effect of the compounds was dose dependent. From acute toxicity studies in mice, the LD50 values were estimated to be in range of moderate toxicity (89.74 to 243 mg/kg). The most active of the compounds studied, namely, 3-(4-benzyl-1-piperazinyl-1-phenylpropanols, was also found to be the most toxic. The margin between its safe doses and its LD50 (89.74 mg/kg) was found to be very narrow. Esterification of the 3-(4-benzyl-1-piperazinyl)-1-phenylpropanol led to decrease in its analgesic activity and also a decrease in its toxicity.

Anti-inflammatory effects of crude methanolic extract and fractions of Alchornea cordifolia leaves.

The leaves of Alchornea cordifolia were collected, identified, dried, and reduced to coarse powder and extracted with aqueous methanol. Using various solvent treatments, the powdered dried leaf was fractionated into five fractions, A1, A2, B, C, D and E. The fractions were subjected to phytochemical analysis to identify the biologically active constituents. The anti-inflammatory effects of crude methanolic extract (ME) of Alchornea cordifolia leaves and the five fractions were evaluated using egg-albumen-induced rat hind paw oedema as a model of inflammation. The crude extract was also subjected to acute toxicity test. Fraction A2, which exhibited the most promising anti-inflammatory effect, was also subjected to analgesic and ulcerogenic tests. Phytochemical analysis of the extracts showed the presence of terpenes, sterols, flavonoids, tannins, carbohydrates, glycosides, saponins and traces of alkaloids. The LD(50) of the aqueous ME was found to be 1131.4 mg/kg. The crude ME (50 mg/kg) gave anti-inflammatory activity which was significant (P<0.05) at all the observation times (1-3h). The different solvent fractions exhibited varying degrees of anti-inflammatory activities, with terpenoid fraction (A2) and the tannin-containing multi-component fraction (D) showing very high and significant (P<0.01) activity at 100mg/kg, with percentage inhibition of oedema value of 87.69 each. In conclusion, the aqueous ME of Alchornea cordifolia leaves could be beneficial in the management of different inflammatory disease states. Its anti-inflammatory activity may not be attributed only to the terpenoid content.

An empirical assessment of the possibility of interchangeability between multisource ciprofloxacin hydrochloride tablets marketed in Nigeria.

A critical quality control of seven brands of ciprofloxacin hydrochloride tablets marketed in Nigeria [Cifran (Ranbaxy, Nigeria), Ciproxin (Bayer, Nigeria), Cenox (Micro labs, India), Ciprotab (Fidson Drugs, India), Ciprofloxacin MS1 and MS2 (Sintacrus Medical stores] were carried out with the aim of selecting brands that are interchangeable. The weight uniformity, disintegration time, absolute drug content and in vitro dissolution profile of the various brands of the tablets were evaluated in simulated intestinal fluid (SIF) and simulated gastric fluid (SGF) without enzymes. The concept of dissolution efficiency (DE) was used to predict the likely in vivo availability. The weight uniformity and the disintegration time of most of the tablets were within the acceptable official ranges. The DE varies widely in the two media. Based on the DE in SGF, Cifran, Ciproxin, Cenox and Ciproflox are bioequivalent and therefore interchangeable. In SIF, however only Ciproflox and Ciprofloxacin MS1 (blue label) were bioequivalent with the innovator brand (Ciproxin, Bayer). In vitro dissolution studies using the concept of dissolution efficiency could serve as a rapid means of selecting probable therapeutically effective brands of ciprofloxacin HCl marketed in Nigeria. Using this concept, four brands (Cifran, Ciproflox, Cenox and Ciproxin) have been shown to be bioequivalent.