Purpose: To develop a simple, rapid and improved colorimetric method for the assay of reserpine in tablets
Method: The method is based on the aromatic ring coupling of reserpine with 4-carboxyl-2,6-dinitrobenzene diazonium ion with the consequent formation of an azo adduct. Optimization of reaction conditions and validation were carried out and the method applied to assay of reserpine in tablets.
Result: Reserpine coupled readily with CDNBD and optimization of experimental conditions showed the reaction to be completed in 10 min at room temperature. A 1:1 drug to reagent stoichiometric ratio was obtained for the azo adduct formed. The adduct exhibited a bathochromic shift with respect to the drug and pronounced hyperchromic shift with respect to the reagent. Sample analyses were done using a colorimeter at 470 nm. The assays were linear and reproducible over the concentration range of 2.25 -24 µg/mL. The new method was successfully applied in the assay of reserpine in tablets with a performance similar to the official (USP) spectrophotometric method (p > 0.05). This method represents a profound improvement on the previously reported colorimetric method for reserpine.
Conclusion: The method developed is rapid and could find application in in-process quality control of reserpine.
Purpose: Bee venom (BV) is traditionally used in many inflammatory chronic conditions but its mechanism of action at molecular level is not fully understood. This study was undertaken to elucidate the mechanism of action of bee venom at the molecular level Methods: We used lipopolysaccharide (LPS) stimulation in Raw 264.7 macrophage (RM) cells and studied the effect of BV on cell proliferation, inflammation related protein expression by western blotting and RNA expression by reverse transcriptase polymerase chain reaction (RT-PCR). Results: Bee venom was toxic to RM cells above10 µg/ml but reduced the production of nitric oxide (NO) at 2–10 µg/ml in LPS stimulated RM cells by inhibiting the expression of inducible nitric oxide synthase (iNOS) and cyclooxigenase (COX)-2 via nuclear factor (NF)-κB. However, bee venom also induced the pro-inflammatory cytokine, interleukin (IL)-1β via p38 mitogen activated protein kinase (MAPK) which is known to stimulate inflammatory activity. Conclusion: It seems that NFκB and p38 MAPK signal pathways are involved in triggering the functional activation of LPS-stimulated macrophage. We suggest that some components of bee venom can cause inflammation by inducing IL-1β via p38 MAPK while others act as anti-inflammatory by suppressing iNOS and COX2 via NFκB.
Purpose: To develop a novel colorimetric assay method for mefenamic acid capsules.
Method: The new method (aromatic ring derivatization technique) is based on a diazo coupling reaction using diazotized 4-amino-3,5-dinitrobenzoic acid (ADBA) as a chromogenic derivatizing reagent.
Result: Optimization studies showed that the coupling reaction is very fast and completed in less than 1 minute. A 1:1 drug to reagent stoichiometric ratio was obtained for the azo dye formed. The azo adduct formed exhibits bathochromic shift with absorption maximum (lmax) at 490 nm, which was selected as the analytical wavelength. Lower limit of quantitation of mefenamic acid was 1 mg/ml. The assays were linear over the concentration range of 1 - 6 mg/ml and reproducible. This new method has been successfully applied in the assay of mefenamic acid capsules with accuracy similar to the official (B.P) titrimetric method of assay (p>0.05) and has the advantages of speed, high sensitivity, lower limit of detection and can be automated.
Conclusion: The method developed could find application in in-process quality control of mefenamic acid capsules.
Keywords: Mefenamic acid assay, 4-amino-3,5-dinitrobenzoic acid, colorimetry, diazotization
Trop J Pharm Res, June 2002; 1(1): 15-22
Purpose: The aim of the present study was to characterise gliclazide solid dispersions (SDs) prepared with polyethylene glycol (PEG) 8000 and compare them with SDs in PEG 6000. Methods: Gliclazide SDs containing varying concentrations of PEG 8000 were prepared using the fusion – solvent technique, and their phase solubility behavior and dissolution in 0.1N HCl were assessed at 37°C. The physical state of, and gliclazide-PEG interactions in, SDs and physical mixtures prepared in ratios of 1:1, 1:2 and 1:5 (gliclazide: PEG 8000), respectively, were characterized by x-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Results: The solubility of gliclazide increased with increasing amount of PEG 8000 in aqueous medium. Gibbs free energy (ΔGo tr) values were all negative, indicating the spontaneous nature of gliclazide solubilisation. Dissolution studies indicated a significant increase in the dissolution of gliclazide when dispersed in PEG 8000. FTIR analysis demonstrated the absence of well-defined gliclazide - PEG 8000 chemical interaction while DSC and XRD studies indicated the amorphous /microcrystalline state of gliclazide in the SDs. Conclusion: In both solid dispersions and physical mixture, PEG 8000 increases the solubility and dissolution rate of gliclazide. The increased dissolution rate of gliclazide may be due to the formation of microcrystals, increased wettability and dispersibility in systems containing PEG 8000.
Purpose: Gliclazide has been found to form inclusion complexes with β- cyclodextrin (β-CD) in solution and in solid state. The present study was undertaken to determine a suitable method for scaling up gliclazide-β-CD inclusion complex formation and to evaluate the effect of some parameters on the efficiency of complexation. Method: The solid inclusion complexes of gliclazide and β-cyclodextrin were prepared at a molar ratio of 1:1 and 1:2 by mixing, kneading, and coprecipitation methods both on small and large scales. The effect of parameters such as kneading time and temperature on complexation was also studied. Characterization was performed using infrared spectroscopy, X-ray diffractometry, and dissolution studies. In vitro release studies were carried out in phosphate buffer (pH 6.8). Result: All the methods of preparation of complexes were found to be useful in increasing the solubility of gliclazide except mixing method where the rise in solubility was not significant. Both kneading and co-precipitation methods in 1:2 molar ratios were found to be equally effective in improving the solubility of gliclazide. The formation of inclusion complexes was evident in these formulations as shown by IR and XRD studies. But when carried out on a large scale, co-precipitation method was found to be more tedious and time-consuming than kneading method. Moreover percent recovery of complexes in the kneading method was found to be 98.76% as compared to 92.05% in case of co-precipitation method. Conclusion: Drug content studies, IR spectroscopic studies, X-Ray diffractometry studies and in vitro dissolution study data indicated that inclusion complexes prepared by kneading method in 1:2 molar ratios were suitable for improving the solubility of gliclazide. The same formulation was prepared at large scale and optimum formulation conditions were established.
Purpose: In the present study, six flavonoids (5,7-dimethoxyflavanone-4'-O-β-D-glucopyranoside, 5,7dimethoxyflavanone-4'-O-[2''-O-(5'''-O-trans-cinnamoyl)-β-D-apiofuranosyl]-β-D-glucopyranoside, naringenin-7-O-β-D-glucopyranoside, 5,7,3'-trihydroxy-flavanone-4'-O-β-D-glucopyranoside, rutin, and nicotiflorin) isolated from Galium fissurense , Viscum album ssp. album and Cirsium hypoleucum were screened against extended-spectrum β-lactamase producing multidrug-resistant (trimetoprimesulphametoxazole, sulbactam-ampicillin, clavulonate-amoxicilin, ceftriaxon, cefepime, imipenem, ceftazidime, tobramicin, gentamicin, ofloxacin, ciprofloxacin) bacteria Klebsiella pneumoniae (ESβLs). Methods: We performed susceptibility testing according to the Clinical and Laboratory Standards Institute (CLSI, formerly NCCLS) and used an inhibition endpoint for determination of the minimum inhibition concentrations (MICs). Results: All the flavonoids showed in vitro antimicrobial activity against all the isolated strains of K. pneumoniae similar to the control antibacterial (ofloxacin) at the concentrations of 32 -64 µg ml-l; another control, ampicillin, had no activity. Since, ESβL-producing strains are known to be resistant to all β-lactam antibiotics, our results fall notably within the concentration range for antimicrobial activity. Conclusion: To the best of our knowledge, this is the first report of the study of the activity of these flavonoids against (ESβL)-producing K. pneumoniae and may throw light to the low-toxicity of flavonoids, and their potentials for developing therapies for infections caused by ESβL-producing bacteria in the future. Further work is under investigation to identify their precise antibacterial mechanism.
Purpose: To evaluate the microbial load on 17 randomly selected plant samples from 60 ethnobotanically collected medicinal plants from five local markets in Abeokuta, Ogun State, Nigeria. Method: The pour plate method was used to cultivate serially diluted portions of the medicinal plant samples investigated. Enumeration of bacteria was carried out on nutrient agar (NA) while that of fungi was effected on Sabouraud agar (SA). Results: The identified microbial isolates include 12 bacterial and 6 fungal genera. The mean heterotrophic bacteria counts of the different herbal samples ranged from 1.3 × 10 5 cfu/g ( Cnestis ferruginea ) to 6.7 × 10 6 cfu/g ( Daniellia oliveri ), while total fungal propagule counts ranged from 0.0 × 10 1 cfu/g ( Terminalia superba , Cola gigantea , Rauwolfia vomitoria , Zingiber officinale and Argemone mexicana ) to 7.1 × 10 6 cfu/g ( Nesogordonia papaverifera ). The synopsis and frequency (prevalence rate) of microbial species isolation showed that Bacillus spp. (82.4 %) and Mucor spp. (47.1 %) had the highest prevalence rates among bacteria and fungi, respectively. Conclusion: The findings from this study emphasized the need for constant quality assessment of herbal drugs on sale in order to ensure the production of therapeutic products suitable for human consumption.
Purpose: To assess the microbiological quality of some milk products in Abuja, Nigeria capital city; and the resistance of isolates to some broad spectrum antibiotics.
Method: Three packs of different brands of yoghurt and pasteurized milk purchased from four different locations were assessed in duplicate. Isolates were identified using growth on agar and broth, Gram's reaction, colony morphology, biochemical tests results and criteria for disregarding negative cultures. Resistance of isolates from pasteurized milk was determined using the antibiotic sensitivity test (zones of inhibition). Results: 33 bacterial and 12 fungal isolates belonging to 9 and 3 genera respectively were identified
from the yoghurt samples. Presence of yeast was found to increase the microbial load of bacterial groups and decrease the load of live and active cultures which was absent in 33% of yoghurt samples. 27% of samples were heat-treated and contained no LAC. A total of 19 bacterial isolates belonging to 6 genera were identified from the pasteurized milk samples. Milk quality based on methylene blue decolourization time measurement revealed that 49% of the assessed samples were of excellent quality, 37% of good quality, 14% of fair quality, and 0% of poor quality. No milk sample was sterile. Among the three antibiotics tested for resistance on the isolated bacterial strains, three different resistance patterns
were observed. Conclusion: Our study shows that mesophilic yeast was the main cause of yoghurt spoilage. Sampled yoghurt is unlikely to make a vital input to LAC intake in Nigerian diets and poses some yet undefined risk. Visual inspection of packages, quality assessment of diary plants/vessels and packaging materials, dye reduction tests, refrigeration at all times, and resistance testing should be critically considered before the use of recommended antibiotics.
Purpose: Hygrophilaspinosa T. Anders (Acanthaceae) is commonly used in the traditional system of medicine for the treatment of inflammation, pain, jaundice, rheumatism, arthritis, anaemia, etc. In the present study, we investigated the anti-inflammatory and antipyretic activities of the petroleum ether, chloroform, alcoholic and aqueous extracts of the leaf of this plant. Methods: The anti-inflammatory activity of the various extracts was studied based on their effects on carrageenan-induced paw oedema in rats while antipyretic activity was evaluated on the basis of their effect on Brewer’s yeast-induced pyrexia in rats. The extracts were screened for alkaloids, steroids, proteins, flavonoids, saponins, mucilage, carbohydrates, organic acids, fats and oils. Results: Preliminary phytochemical screening revealed the presence of alkaloids, steroids, proteins, flavonoids, fats and oils, tannins, mucilage and organic acids in the leaves of H. spinosa. Chloroform and alcoholic extracts of leaves of H. spinosa produced significant (p < 0.05 and p < 0.01) anti-inflammatory and antipyretic activities in a dose-dependent manner. On the other hand, petroleum ether and aqueous extracts did not show significant anti-inflammatory and antipyretic activities. The maximum anti-inflammatory activities produced by chloroform and alcoholic extracts (400 mg/kg) were 33.7% and 47.5%, respectively. These two extracts also reduced elevated body temperature in rats at 200 and 400 mg/kg body weight doses throughout the observation period of 6 h. Conclusion: Chloroform and alcoholic extracts of H. spinosa leaves have anti-inflammatory and antipyretic activities.
Purpose: The electron donor-acceptor interaction between drugs which act as electron donors and some electron-deficient compounds (π acceptors) has severally been utilized as an analytical tool for the quantitation and qualitative assessment of such drugs. The objective of this study, therefore, was to develop an assay procedure for dosage forms of chloroquine phosphate based on its reaction with chloranilic acid which resulted in the formation of a charge-transfer complex. Methods: The complex formation between chloroquine phosphate and chloranilc acid as evidenced by the instantaneous change in colour of a solution of chloranilic acid in dioxan from yellow to purple upon addition of a solution of chloroquine phosphate in chloroform was monitored spectrophotometrically to determine the wavelength of maximum absorption. The stoichiometry of the complex formed was evaluated using the Job’s continuous variation method while the thermodynamics of the complex was evaluated spectrophotometrically with the aid of the Benesi-Hildebrand plot. Results: Spectrophotometric absorption studies showed evidence of the formation of strongly bonded and highly stable charge-transfer complex between chloroquine phosphate and chloranilic acid in a 3:2 stoichiometry in non-aqueous medium. The transitions involved were detected at wavelengths longer than those of the individual pure substances in the visible region of the spectrum. Conformity with Beer’s law was evident over the concentration range 0.8 – 8.0 mg/100 ml of chloroquine phosphate; thus making it possible for an accurate quantitative determination of the drug. Conclusion: The studied complexation phenomenon formed a basis for the quantitative determination of both pure samples and individual dose units of chloroquine phosphate and is considered a simple, sensitive and precise analytical tool with high accuracy for routine analysis of chloroquine phosphate in developing countries where sophisticated analytical instruments may not be available.
Purpose: The objective of the study was to develop matrix tablets for oral controlled release of aceclofenac using ethyl cellulose, guar gum and various grades of cellulose polymers. Methods: Possible drug-excipient interaction was evaluated by high performance liquid chromatography (HPLC) and Fourier infrared spectroscopy (FTIR). The tablets prepared were assessed for their physicochemical, in vitro drug release at pH1.2, 4.5, 6.8 and 7.5 and stability characteristics. Comparison with a ′once daily′ commercial aceclofenac product was made in the in vitro studies. Results: There was no interaction between aceclofenac and the polymers used as excipients. Furthermore, the physicochemical properties of the tablets were satisfactory. The release profile of one of the formulated aceclofenac tablets (F7), which contained hydroxypropyl methyl cellulose (HPMC K4M), was statistically similar (p < 0.05) to that of the commercial aceclofenac brand in all the dissolution media. The formulated products ware stable and showed no changes in physical appearance, drug content, or dissolution pattern after storage at 40 o C /75 %RH for 6 months. Conclusion: The results indicate that it is feasible to achieve a stable ′once daily′ sustained release aceclofenac tablet formulation by using HPMC K4M of 4000cps viscosity grade as matrix material.
Purpose: The objective of the study was to investigate the ethyl acetate extract of Morindamorindoides (Baker) Milne-Redh (Rubiaceae) (MM-EA) properties against experimental diarrheoa induced by castor oil in albino Wistar rats. Methods: The ethyl acetate extract of Morinda morindoides (250, 500, and 1000 mg/kg body weight) was administered orally to three groups of rats (five animals per group) in order to evaluate the activity of the extract against castor oil-induced diarrhea model in rat. Two other groups received normal saline (5mg/kg) and loperamide (5mg/kg) as positive control. The effect of the extract on intestinal transit and castor oil-induced intestinal fluid accumulation (enteropooling) was assessed. Results: At oral doses of 250, 500, and 1000 mg/kg body weight, the plant extract showed pronounced and dose-dependent antidiarrheal activity. The protective role of the extract at 1000 mg/kg was comparable to that of the reference drug, loperamide (5mg/kg). The extract (1000 mg/kg) produced a decrease in intestinal transit comparable to atropine (5mg/kg), and significantly (p<0.01) inhibited castor oil-induced enteropooling. No mortality and visible signs of general weakness were observed in the rats following the extract administration of up to a dose of 6000 mg/kg. Conclusion: The results showed that the extract of M. morindoides has a significant antidiarrheal activity which supports its use in traditional herbal medicine practice.
Purpose: The fruits of Limonia acidissima Linn are used traditionally in India for the treatment of tumours, asthma, wounds, cardiac debility and hepatitis. The purpose of the present study was to evaluate the wound healing activity of the methanol extract of its fruit pulp (MELA) in incision, excision and dead-space wound models. Methods: Albino rats of either sex were divided into four groups, viz, wounded control, wounded rats administered standard drug, nitrofurazone (2 %), and wounded rats administered MELA 200 and 400 mg/kg, respectively. In incision wound model, wound breaking strength and epithelization period were evaluated, while in excision wound model, wound contraction was studied. In dead-space wound model, granulation tissue dry weight, hydroxyproline levels in dry granulation tissue, as well as superoxide dismutase (SOD) and catalase levels in wet granulation tissue were estimated. Granulation tissue was subjected to histopathological examination in order to determine whether there was healing by formation of collagen in the wound tissue in extract-treated animals. Results: Increased wound breaking strength, decreased epithelization period, increased wound contraction, increased granulation tissue weight and hydroxyproline concentration were observed in the various groups, compared with the control group. Also, increased activity of anti-oxidant enzymes, i.e., higher SOD and catalase levels, were seen in extract-treated groups when compared to controls. Wound healing activity was statistically significant (p < 0.001) in animals treated with 400 mg/kg of the extract. Conclusion: The methanol extract of L. acidissima possesses significant dose-dependant wound healing and anti-oxidant activities; this supports traditional claims for the plant as a wound healer.
Purpose: The objective of this investigation was to isolate marine actinomycetes, screen them for L-asparaginase activity and characterise the enzyme. Methods: Marine actinomycetes were isolated from sediment samples obtained from Tamilnadu and Kerala in India. The isolates were identified as actinomycetes by microscopical and biochemical tests. Production of L-asparaginase was carried out in three different media, namely, solid-state media, Tryptone Glucose Yeast extract (TGY) broth and Tryptone Fructose Yeast extract (TFY) broth.. The enzyme was purified to near homogeneity by ammonium sulphate precipitation, dialysis, gel filtration on Sephadex G-100 column and SDS-PAGE. Results: Among 10 marine isolates subjected to preliminary screening, only isolates S3, S4 and K8 showed potential for L-asparaginase activity. All three marine soil isolates synthesized asparaginase with yield ranging from 24.6 to 49.2 IU/ml. Soil isolate S3 showed the highest productivity of 49.2 IU/ml with a protein content of 65 µg/ml and optimum activity at pH 7.5 and 50 ºC. The apparent Km value for the substrate was 25 µM. Mg2+ ion slightly stimulated activity while Cu2+, Zn2+ and EDTA were inhibitory. Conclusion: The study revealed that marine actinomycetes may be a potential source of high yield, high substrate specificity L-asparaginase, which is an anti-leukaemia agent.
Purpose: To isolate and characterize antibiotic producing actinomycetes from soil samples in Belgaum, Karnataka, India. Methods: Crowded plate technique was used for the isolation of actinomycetes in media such as soybean - casein digest medium and actinomycetes isolation agar. The morphological and cultural characterization of one of the selected strains, designated A-4, was performed as per International Streptomycete Project (ISP). Results: Morphological and cultural studies showed that A-4 belonged to the Actinomycete genus. The morphological and cultural characteristics of the A-4 mutant showed cellular and aerial growth as well as soluble pigment formation in various ISP media. Conclusion: Findings from this investigation revealed that the selected strain, A-4, is an actinomycete.
Purpose: The purpose of the study is to evaluate the antimicrobial and antitumor activities of Stevia rebaudiana (Asteraceae) leaf extracts. Methods: Four solvent extracts (ethyl acetate, acetone, chloroform and water) of Stevia rebaudiana leaves were investigated against Staphylococcus aureus , Salmonella typhi , Escherichia coli , Bacillus subtilis , Aeromonas hydrophila and Vibrio cholerae by using agar well diffusion method. Candida albicans , Cryptococcus neoformans , Trichophyton mentagrophytes and Epidermophyton species were used to test anti-yeast and antifungal activity. The cytotoxic effects of the extracts on Vero and HEp2 cells were assayed using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT]. Results: Among the four extracts tested, acetone extract had effective antibacterial potential, followed by ethyl acetate extract. The acetone extract showed greater activity against Gram-positive than against Gram-negative organisms. All the extracts were active against Epidermophyton species and Candida albicans . The 1:8 dilution of the acetone extract was non-toxic to normal cells and also had both anticancer and anti-proliferative activities against cancerous cells. Conclusion: The study confirms the antimicrobial and antitumor activities of Stevia rebaudiana leaves extracted using various solvents, and is therefore, a potential drug that requires further studies and development.
Calendula officinalis Linn. (Asteraceae) is used medicinally in Europe, China and India amongst several places in the world. It is also known as "African marigold" and has been a subject of several chemical and pharmacological studies. It is used in traditional medicine, especially for wound healing, jaundice, blood purification, and as an antispasmodic. Chemical studies have underlined the presence of various classes of compounds, the main being triterpenoids, flavonoids, coumarines, quinones, volatile oil, carotenoids and amino acids. The extract of this plant as well as pure compounds isolated from it, have been demonstrated to possess multiple pharmacological activities such as anti-HIV, cytotoxic, antiinflammatory, hepatoprotective, spasmolytic and spasmogenic, amongst others. In this review, we have explored the phytochemistry and pharmacological activities of C. officinalis in order to collate existing information on this plant as well as highlight its multi-activity properties as a medicinal agent. This is as a result of the worldwide cultivation of the plant and increasing published reports on it.
Purpose: To evaluate the ethanol extracts of the flowers, leaves, and stems of Centaureatchihatcheffii Fischer & C.A. Meyer (Asteraceae) for their anti-inflammatory and analgesic activities in male Swiss albino mice. Methods: For the evaluation of anti-inflammatory activity, hind paw oedema was induced in the mice with carrageenan and prostaglandin-E2 (PGE2) and the mice received either 100 and 200 mg/kg body weight doses of the flower extract or 200 mg/kg body weight dose of the leaf and stem extracts. Furthermore, ear oedema was induced in other groups of mice with 12-O-tetradecanoyl-13-acetate (TPA) and then administered with 0.5 mg/ear dose of the extract of either of the three plant parts. In order to evaluate analgesic activity, p-benzoquinone-induced abdominal constriction test was used with 100, 200 and 400 mg/kg body weight doses of the flower or 200mg/kg body weight dose of the leaf and stem extracts administered. Indomethacin and acetylsalicylic acid were the reference drugs for antiinflamatory and analgesic evaluations, respectively. Phytochemical screening of the flower extract was carried out by thin layer chromatography (TLC). Results: The results of evaluation of the anti-inflammatory activities induced by carrageenan and PGE2 showed that the flower extract diminished cyclo-oxygenase activitiy at the 200 mg/kg dose to the same level as the reference drug, indomethacin. However, no anti-inflamatory activity was seen in the TPAinduced ear oedema model. The extracts from all three parts of the plant showed analgesia in pbenzoquinone-induced abdominal constriction test. TLC analysis of the flower extract indicated the presence of sesquiterpen lactones, which may have been responsible for the analgesic activity. Conclusion: Our results support the use of C. tchihatcheffii in traditional medicine in Turkey for their anti-inflammatory and analgesic properties.
Purpose: A 1: 1: 2 mixture of exudates of Anchomonas difformis, Cyrtrospherma senegalense and Pycanthus angolensis is claimed to be used for the treatment of corneal ulcers. The purpose of the study is to evaluate the phytochemical constituents, antibacterial activities and the effectiveness of a mixture of these exudates in the treatment of corneal ulcers as claimed in Traditional medicine practice.
Method: Fresh exudates were collected in different containers. They were reduced to dryness and each residue tested for phytochemical constituents. Exudates of P. angolensis was further tested for antimicrobial activities and its effect on chemical – induced corneal ulcers in rabbits.
Result: Only reducing sugars were detected in exudates of A. angolensis and C. senegalensis. Bioactive constituents detected in exudates of P. angolensis were the reducing sugars and phenolic compounds- tannins and flavonoids. This also showed antimicrobial activity against the organisms used. It healed the NaOH – induced corneal ulcers in rabbits within ten of days of treatment.
Conclusion: Exudates of P.angolensis contained bioactive constituents and exhibited antibacterial activity, and healed the corneal ulcers induced in rabbits. Its use in traditional practice for healing corneal ulcers is rational, even in the absence of exudates of A. angolensis and C. senegalensis.
Purpose: The aim of the present study was to investigate antioxidant and antimicrobial effects of the methanol extract of Heracleum nepalense D.Don roots.
Method: The antimicrobial effect was determined by agar dilution and disc diffusion method. The free radical scavenging potential was studied by using different antioxidants models of screening using vitamin E (5mM) as standard.
Results: The crude methanol extract of H.nepalense root was found to be active against both Gram-positive and Gram-negative organisms. The ethyl acetate soluble fraction of the extract showed similar activity against these organisms. Similarly, the methanol extract at 1000 mg. ml-1 and the ethyl acetate fraction at 50 mg. ml-1 exhibited significant antioxidant activity in ferrous sulphate induced lipid peroxidation, 1,1- diphenyl- 2-picryl hydrazyl (DPPH), Hydroxyl radical and Superoxide scavenging models.
Conclusions: The study confirms the possible antioxidant and antimicrobial potentiality of the plant extract. Presence of flavonoid alone or in combination with its other components could be responsible for the activity.
Purpose: Dregeavolubilis Benth , commonly known as Jukti in Bengal, is used in the treatment of boils and abscesses from ancient times. The purpose of this study is to elucidate the active compounds and as well as their anti-leishmanial and anti-tumour activities. Methods: Dried and crushed fruits of Dregea volubilis were extracted by petroleum ether (40 -60°C); the best solvent system had first been verified by analytical Thin Layer Chromatography (TLC). The extract was subjected to TLC and column chromatography (CC) to isolate the pure compounds. Spectra data were obtained by Infra Red pectroscopy, Mass Spectroscopy and Nuclear Magnetic Resonance -Proton Magnetic Resonance (PMR), Carbon Magnetic Resonance (CMR) and Distortionless Enhancement by Polarization Transfer (DEPT) -for structure elucidation of the isolated compound(s). One of the compounds isolated was screened for anti-leishmanial activity against promastigotes of Leishmania donovani and anti-tumour activity on K562 leukemic cell line. Results: A pentacyclic triterpenoid compound was isolated and designated as taraxerone, and then characterized as d-friedoolean-14-en, 3 one together with ß-sitosterol and a long chain lipid fraction.. This compound showed in vitro anti-leishmanial activity against promastigotes of Leishmania donovani (strain AG 83) and anti-tumour activity on K562 leukemic cell line. Conclusion: A pentacyclic triterpenoid compound designated as taraxerone and characterized as Dfriedoolean-14-en, 3 one together was successfully isolated. The structure was determined on the basis of spectral analysis (IR, MASS, NMR (PMR, CMR and DEPT) and the compound demonstrated in vitro anti-leishmanial and anti-tumour activities.
Purpose: Microbial infections often produce pain and inflammation. Chemotherapeutic, analgesic and anti-inflammatory drugs are prescribed simultaneously in normal practice. The compound possessing all three activities is not common.The purpose of the present study was to examine whether molecular modification might result in detection of new potential antirheumatic drugs having antimicrobial activities.
Method: A series of novel 4-(5′-substituted aryl-4′, 5′-dihydropyrazole-3′-yl-amino) phenols 2a-f have been synthesized by treating substituted aryl-N-chalconyl amino phenols 1a-f with hydrazine hydrate. The starting materials were synthesized from p-aminoacetophenone. Their structures were confirmed by IR, 1H NMR spectral data. The synthesized compounds were investigated for analgesic, ant-inflammatory and antimicrobial activities.
Result: The data reported in Tables 2, 3 & 4 shows that effect of variation in chemical structure on activity was rather unpredictable. Seldom did a particular structural modification lead to uniform alteration in activity in all tests. The substitution which appeared to be most important for high order of activity in the greatest number of test was the p-choloroaryl group. The introduction of p-nitro and p-hydroxy group in aryl moiety of the pyrazole analogs 2c and 2e produce compounds with potent analgesic, anti-inflamatory and, in a few cases, antimicrobial properties.
Conclusion: The observed increase in analgesic, anti-inflammatory and antimicrobial activities are attributed to the presence of 4-NO2, 2-OH and 4-Cl in phenyl ring at 5-position of pyrazoline ring of synthesized compounds. In some cases their activities are equal or more potent than the standard drugs.
Purpose: The antimicrobial activity of the 90 % ethanol extract of the aerial parts of Sida acuta Burm. F. (Malvaceae) was investigated in other to verify its claimed ethno medicinal use in the treatment of microbial infections.
Method: The antimicrobial activity of the extract was tested against standard strains and clinical isolates of some aerobic bacteria and a fungus using the Agar well diffusion method. Commercial antibiotics were used as positive reference standards to determine the sensitivity of the strains.
Results: The extracts showed significant inhibitory activity against standard strains and clinical isolates of Staphylococcus aureus, clinical isolates of Bacillus subtilis and Streptococcus faecalis. The MIC values obtained using the Agar-dilution test ranged from 5.0 mg/ml. – 10.0 mg/ml. Neither the concentrated extract nor its dilutions inhibited Esherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa and Candida albicans
Conclusion: The results demonstrate that the crude extract of the aerial parts of Sida acuta has a narrow spectrum of activity and suggest that it may be useful in the treatment of infections caused by Gram positive aerobic bacteria.