Bioactivity-guided isolation of the antidiabetic principle in Pterocarpus Santalinoides leaf extract

Abstract Pterocarpus santalinoides is used in Nigerian ethnomedicine to treat diabetes mellitus. This study aimed to establish the antidiabetic property of the plant, and isolate and characterize its active principle. Dried and pulverized leaves (500 g) of P. santalinoides were extracted with 1.8 L of 80 % hydromethanol by cold maceration. The dried extract (10 g) was partitioned into n-hexane, ethyl acetate (EtOAc), n-butanol, and water. Antidiabetic activitiy-guided isolation by column chromatographic separation of the EtOAc soluble and purification of the sub-fractions by repeated preparative thin layer chromatography (pTLC) yielded a C-glycosyl flavonoid, identified as isovitexin. The chemical structure was elucidated based on high-resolution mass spectroscopy, 1D, and 2D nuclear magnetic resonance spectroscopic analyses. Alloxan-induced diabetic rat model was adopted for antidiabetic screening. The extract of P. santalinoides (100-200 mg/kg), fraction F4 (50 mg/kg), sub-fraction F4.3 (10 mg/kg), and the semi-purified compound F4.3.2 (5 mg/kg) significantly (p<0.05) reduced the fasting blood glucose of alloxan-induced diabetic rats, causing 48.4, 69.4, 57.7 and 64.5 % antidiabetic activity respectively, compared with > 68 % recorded in glibenclamide (2 mg/kg) control. These results reveal that isovitexin is the antidiabetic principle in P. santalinoides

Antidiabetic activity of heart wood of Pterocarpus marsupium Roxb. and analysis of phytoconstituents.

The crude powder, ethanolic extract and aqueous, chloroform, hexane and n-butanol soluble fractions of ethanolic extract of heart wood of P. marsupium showed marked improvement on oral glucose tolerance post sucrose load in normal rats. All these fractions except aqueous fraction showed improvement on oral glucose tolerance post sucrose load on streptozotocin (STZ)-induced diabetic rats. The crude powder, ethanolic extract and hexane and n-butanol fractions showed marked decline in blood glucose level on STZ-induced diabetic rats. The ethanolic extract (100 mg/kg body weight) when given to STZ-induced diabetic rats for 10 consecutive days declined blood glucose, improved OGTT and increased their serum insulin levels. The ethanolic extract also showed marked improvement on oral glucose tolerance on high fat-low dosed STZ-induced diabetic rats and neonatally STZ treated rats. The ethanolic extract of P. marsupium also showed marked antidyslipidemic effects on high fat diet fed Syrian golden hamsters. Altered renal and hepatic function markers and serum insulin levels of high fat diet fed-low dosed STZ-treated diabetic rats were also found towards normalization when these animals were treated with ethanolic extract of P. marsupium for 28 consecutive days. The four out of five phenolic C-glycosides isolated from n-butanol fraction of ethanolic extract of P. marsupium enhanced glucose uptake by skeletal muscle cells (C2C12) in a dose dependent manner. It may primarily be concluded that phenolic-C-glycosides present in P. marsupium heart wood are the phytoconstituents responsible for the antihyperglycemic activity and validate the claim of antidiabetic activity of heart wood of P. marsupium.

Homopterocarpin contributes to the restoration of gastric homeostasis by Pterocarpus erinaceus following indomethacin intoxication in rats

OBJECTIVE@#To investigate the restorative effect of Pterocarpus erinaceus (P. erinaceus) and homopterocarpin, an isoflavonoid isolated from it, on indomethacin-induced disruption in gastric homeostasis in rats.@*METHODS@#Adult rats were divided into five groups and fasted for 48 h before treatment. Group 1 received olive oil (vehicle), group 2 received 25 mg/kg indomethacin while groups 3-5 received cimetidine (100 mg/kg), homopterocarpin (25 mg/kg) and P. erinaceus ethanolic stem bark extract (100 mg/kg) respectively. After 1 h, all the groups except group 2 were administered 25 mg/kg of indomethacin. One hour later, the rats were sacrificed and the ulcer index and other gastroprotective indices were evaluated.@*RESULTS@#Indomethacin caused significant injury to the stomach of the rats as reflected in the ulcer indices (9.0±1.4) as compared with that of control (2.0±0.0). Equally, there were significant increases in gastric acid concentration and malondialdehyde level in the stomachs of the ulcerated animals compared with the control. However mucus content, reduced gluthatione level and gastric pH were significantly reduced in the ulcerated animals compared with the control. Pretreatment with either Pterocarpus bark extract or homopterocarpin reversed the effects of indomethacin on the evaluated parameters.@*CONCLUSIONS@#These results indicate that both homopterocarpin and Pterocarpus extract offered gastroprotection against indomethacin-induced ulcer by antioxidative mechanism and the modulation of gastric homeostasis. The results also suggest that homopterocarpin might be responsible for, or contribute to the antiulcerogenic property of P. erinaceus.

Actividad antimicrobiana de extractos de Psidium friedrichsthalianum L., Pterocarpus hayesii L., Tynanthus guatemalensis L. y Spondias purpurea L / Antimicrobial activity of Psidium friedrichsthalianum L., Pterocarpus hayesii L., Tynanthus guatemalensis L. and Spondias purpurea L. extracts

There is not much information on antimicrobial activity presented by several species traditionally used as medicinal plants in Tabasco. Antimicrobial activity of ethanolic and hexanic extracts from leaf and bark of guayaba agria (Psidium friedrichsthalianum L.), palo de sangre (Pterocarpus hayesii L.) chichimecate (Tynanthus guatemalensis L.) and ciruela (Spondias purpurea L.) was evaluated for against Staphylococcus aureus ATCC 25923, Salmonella typhimurium ATCC 14028 and Bacillus cereus ATCC 11778 by the use of agar diffusion method. Results indicate that the hexanic extract of every one of the plant species presented antimicrobial activity on at least one of the evaluated microorganisms meanwhile bark hexanic extracts did not present activity against the three microorganisms tested. The extracts that presented a Minimal Inhibitory Concentration (MIC) of < 7.50 mg mL-1 against B. cereus were both leaf ethanolic of P. friedrichsthalianum and S. purpurea and the T. guatemalensis leaf hexanic extract as well as P. friedrichsthalianum bark hexánico extract against S. aureus and S. typhimurium.

Existe poca información sobre la actividad antimicrobiana que pueden presentar varias plantas que han sido reportadas con uso medicinal tradicional en el Estado de Tabasco. Se evaluó la actividad antimicrobiana de los extractos etanólico y hexánico de hoja y corteza de cuatro plantas utilizadas como medicinales: guayaba agria (Psidium friedrichsthalianum L.), palo de sangre (Pterocarpus hayesii L.), chichimecate (Tynanthus guatemalensis L.) y ciruela (Spondias purpurea L.). La actividad antimicrobiana se evaluó contra Staphylococcus aureus ATCC 25923, Salmonella typhimurium ATCC 14028 y Bacillus cereus ATCC 11778 mediante el método de difusión en agar. Los resultados indican que el extracto hexánico de cada una de las plantas presentaron actividad antimicrobiana al menos en uno de los microorganismos evaluados mientras que los extractos hexánicos de corteza no presentaron actividad contra ninguno de los tres microorganismos ensayados. Los extractos que presentaron una Concentración Mínima Inhibitoria (CMI) igual o menor de 7.50 mg mL-1 contra B. cereus fueron los etanólicos de hoja de P. friedrichsthalianum y S. purpurea y el hexánico de hoja de T. guatemalensis así como el extracto hexánico de corteza de P. friedrichsthalianum contra S. aureus y S. typhimurium.

Pharmacological properties and related constituents of stem bark of Pterocarpus erinaceus Poir. (Fabaceae)

OBJECTIVE@#To screen methanol and dichloromethane extracts of stem bark of Pterocarpus erinaceus for anti-inflammatory, analgesic, in vitro antioxidant activities and phytochemical analysis.@*METHODS@#Anti-inflammatory activity was determined by using carrageenan induced-edema of mice paw and croton oil-induced edema of mice ear; analgesic effect was evaluated using acetic acid-induced writhing. Phytochemical screening of extracts was performed by thin layer chromatography. The chromatographic fractionation led to the isolation of main active components as friedelin, lupeol and epicathechin. The structures were established by TLC and nuclear magnetic resonance studies.@*RESULTS@#Both methanol and dichloromethane extracts, friedelin, lupeol and epicatechin showed a significant anti-inflammatory effect using croton oil induced-ear edema. Furthermore, the action of dichloromethane extract was more important. At the doses of 100 and 200 mg/kg, the methanol extract was able to reduce the carrageenan induced-hind paw edema, while at the doses of 100, 200 and 400 mg/kg, it showed an important analgesic effect against writhing induced by acetic acid injection of 38.8%, 68.0% and 74.3%, respectively. Antioxidative properties of methanol extract and its dichloromethane and ethyl acetate fractions were assessed by using the 1,1-diphenyl-2-picrylhydrazyl method. The methanol extract showed the stronger radical scavenging activity than dichloromethane and ethyl acetate fractions, with an antiradical power of 5, 3.5 and 2 respectively. The main components isolated from these extracts as friedelin, lupeol and epicathechin were responsible of these activities.@*CONCLUSIONS@#The results suggest that the stem bark extracts of Pterocarpus erinaceus possessed important anti-inflammatory, analgesic activities and strong antioxidant properties, therefore, they could be used as potential natural ingredients in the pharmaceutical industry.

Antidiarrheal activity of Pterocarpus erinaceus methanol leaf extract in experimentally-induced diarrhea

OBJECTIVE@#To investigate the antidiarrheal activity of the methanol leaf extract of Pterocarpus erinaceus in vivo.@*METHODS@#The methanol leaf extract of Pterocarpus erinaceus was evaluated using different doses (100, 200 and 400 mg/kg body weight) orally for antidiarrheal activity using castor oil-induced diarrhea, charcoal meal transit time and castor oil-induced enteropooling in different groups of albino Wistar mice. The activity of the extract at different doses were compared to diphenoxylate (5 mg/kg) and atropine sulphate (3 mg/kg) which were used as standard reference drugs and also to the distilled water administered negative control group of mice.@*RESULTS@#The extract at the doses used caused a significant (P< 0.01) reduction in the wet faeces passed by the mice in the castor oil-induced diarrhea, decreased the distance travelled by the charcoal meal by up to 54.8% and also caused a dose dependent and significant (P< 0.001) reduction in the intraluminal fluid accumulation in the castor oil-induced enteropooling.@*CONCLUSIONS@#Our results indicate that Pterocarpus erinaceus extract produced significant antidiarrheal activity and the action may attribute to inhibition of gastrointestinal movement and fluid secretion.

Cedrol Enhances Extracellular Matrix Production in Dermal Fibroblasts in a MAPK-Dependent Manner

BACKGROUND: The extracellular matrix (ECM) produced by dermal fibroblasts supports skin structure, and degradation and/or reduced production of ECM are the main causes of wrinkle formation. OBJECTIVE: The aim of this study was to identify the active ingredient that enhances ECM production in dermal fibroblasts. METHODS: Polarity-based fractionation was used to isolate the active ingredient from natural extracts, and the effects of cedrol (isolated from Pterocarpus indicusirginia) on ECM production in cultured human dermal fibroblasts was investigated by reverse transcription-polymerase chain reaction, enzyme linked immunosorbent assay, and Western blot analysis. RESULTS: Cedrol accelerated fibroblast growth in a dose-dependent manner and increased the production of type 1 collagen and elastin. Phosphorylation of p42/44 extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and Akt was markedly increased by cedrol, indicating that enhanced ECM production is linked to activation of intracellular signaling cascades. CONCLUSION: These results indicate that cedrol stimulates ECM production, with possible applications to the maintenance of skin texture.

Chitosan-based polyherbal toothpaste: As novel oral hygiene product.

Objective: The objective of the present work was to develop chitosan-based polyherbal toothpaste and evaluate its plaque-reducing potential and efficacy in reduction of dental pathogens. Materials and Methods: Antimicrobial activity of herbal extracts against dental pathogens were performed by using disk diffusion method. The pharmaceutical evaluation of toothpaste was carried out as per the US Government Tooth Paste Specifications. A 4-week clinical study was conducted in patients with oro-dental problems to evaluate the plaque removing efficacy of chitosan-based polyherbal toothpaste with commercially available chlorhexidine gluconate (0.2% w/v) mouthwash as positive control. Total microbial count was carried out to determine the percentage decrease in the oral bacterial count over the period of treatment. Result: Herbal extracts were found to possess satisfactory antimicrobial activity against most of the dental pathogens. Chitosan-containing polyherbal toothpaste significantly reduces the plaque index by 70.47% and bacterial count by 85.29%, and thus fulfills the majority of esthetic and medicinal requirements of oral hygiene products. Conclusion: Chitosan-based polyherbal toothpaste proves itself as a promising novel oral hygiene product as compared with currently available oral hygiene products. A further study to confirm the exact mechanism and active constituents behind antiplaque and antimicrobial activity of chitosan-based polyherbal toothpaste and its efficacy in large number of patient population is on high demand.

Contribution a la connaissance des plantes medicinales de la reserve de biosphere du Dja au Cameroun : plantes utilisees dans le traitement des maux de dos

L'enquete ethnobotanique menee entre Janvier et Avril 1994 en peripherie de la reserve de biosphere du Dja au Cameroun a permis de recenser 24 especes vegetales utilisees localement par les populations Badjoue; Bulu; Zime et pygmees Baka dans le traitement des maux de dos. Ces especes sont distribuees dans 24 genres et 17 familles. Les especes telles que Baillonella toxisperma; Piptadeniastrum africanum et Pterocarpus soyauxii largement citees dans le Dja sont egalement connues pour les memes usages dans d'autres regions du Cameroun ou dans d'autres pays africains

Cardiotonic activity of aqueous extract of heartwood of Pterocarpus marsupium.

The present study was undertaken to evaluate cardiotonic activity of aqueous extract of heartwood of P. marsupium. This plant species contains 5,7,2-4 tetrahydroxy isoflavone 6-6 glucoside which are potent antioxidant and are believed to prevent cardiovascular diseases. Cardiotonic effect of aqueous extract of heartwood of P. marsupium was studied by using isolated frog heart perfusion technique (IFHP). Calcium free Ringer solution was used as vehicle for administration of aqueous extract of P. marsupium as a test extract and digoxin as a standard. A significant increase in height of force of contraction (positive inotropic effect) and decrease in heart rate (negative chronotropic effect) at a very low concentration (0.25 mg/ml) was observed with test extract as compared to the same dose of a standard digoxin. The present results indicated that a significant increase in height of force of contraction with decrease in heart rate was observed as the dose of test extract increased. The test extract produced cardiac arrest at 4 mg/ml, a higher concentration, as compared to standard, digoxin (0.5 mg/ml). Compared to digoxin, a drug with narrow therapeutic window, P. marsupium showed wide therapeutic window.