Chrysophyllum albidum fruit ethanol extract ameliorates hyperglycaemia and elevated blood pressure in streptozotocin-induced diabetic rats through modulation of oxidative stress, NF-κB and PPAR-γ.

Oxidative stress and inflammation arising from hyperglycaemia have been identified as important targets in mitigating hyperglycaemia-induced organ dysfunction in diabetics. Chrysophyllum albidum fruit is commonly consumed as fruit snacks because of its beneficial effects in diabetes management. This study aim to evaluate the protective mechanisms of Chrysophyllum albidum fruit extract (CAFE) in streptozotocin-induced rats involving attenuation of oxidative stress, nuclear factor-kappa B (NF-κB) and peroxisome proliferator-activated receptor-gamma (PPAR-γ). CAFE was investigated for in vitro antioxidant and alpha amylase inhibitory activity. Male Wistar rats were made diabetic by single intraperitoneal injection of streptozotocin (60 mg/kg). The rats were then treated with CAFE (100 and 200 mg/kg) and pioglitazone (10 mg/kg) for two weeks. Fasting blood sugar (FBS), blood pressure parameters, lipid profile, oxidative stress parameters, NF-κB and PPAR-γ were determined. The extract showed antioxidant and alpha amylase inhibitory activities. CAFE significantly reduced STZ-induced hyperglycaemia after 7 and 14 days of treatment. CAFE also reduced STZ-induced elevation of diastolic blood pressure and mean arterial pressure and as well reduced atherogenic index in diabetic rats. It significantly decreased lipid peroxidation but increased the enzymatic and non-enzymatic antioxidant markers in the plasma, liver, kidney and pancreas. The immunohistochemical analysis revealed that CAFE significantly decreased hepatic and renal tissues NF-κB while increasing PPAR-γ gene expressions. The results of this study collectively showed the protective effect of Chrysophyllum albidum fruit extract in streptozotocin-induced diabetic rats via modulation of oxidative stress and NF-κB/ PPAR-γ expressions.

Antihypertensive effect of Phragmanthera incana (Schum) Balle on NG-nitro-L-Arginine methyl ester (L-NAME) induced hypertensive rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Phragmanthera incana (Schum) Balle is a member of the African mistletoes that has been reported to be used in ethnomedicine for the treatment of hypertension. AIM: The aim of this study was to investigate the antihypertensive effect of Phragmanthera incana leaf ethanol extract (PILEE) in NG-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. MATERIALS AND METHODS: Phytochemical analysis of PILEE was determined using the Gas chromatography - Mass spectrophotometry (GC-MS) method. Antihypertensive activity was investigated in rats that received PILEE (50, 100 and 200 mg/kg) or captopril (40 mg/kg) daily for 28 days together with oral administration of L-NAME (40 mg/kg). Blood pressure parameters were measured on day 7, 14, 21 and 28. Blood was obtained for determination of serum nitrite, interleukin-6 (IL-6) and tumor necrosis factor, TNF-α. The heart, liver and kidneys were used to determine oxidative stress indices (malondialdehyde, reduced glutathione and catalase). The cardiac tissue was processed for histopathological changes. RESULTS: The GC-MS profiling of PILEE identified 20 compounds namely fatty acid esters. Administration of PILEE (50, 100 and 200 mg/kg) dose dependently and significantly reduced systolic blood pressure and mean arterial pressure in hypertensive rats. PILEE administration significantly (p < 0.05) reversed elevated IL-6 and TNF-α in hypertensive rats. PILEE demonstrated antioxidant activity by attenuating L-NAME-induced elevated malondialdehyde and depletion of reduced glutathione and catalase activity in rat tissues. PILEE treatment demonstrated cardioprotective effect in L-NAME-induced cardiac hyperplasia and necrosis in rats. CONCLUSION: It can be concluded that Phragmanthera incana leaf ethanol extract possess antihypertensive, antioxidant and anti-inflammatory properties, suggesting a protective role in cardiovascular diseases.

Clofibrate, a PPAR-α agonist, abrogates sodium fluoride-induced neuroinflammation, oxidative stress, and motor incoordination via modulation of GFAP/Iba-1/anti-calbindin signaling pathways.

Fluoride is an environmental contaminant that is ubiquitously present in air, water, and soil. It is commonly added in minute quantity to drinking water, toothpaste, and mouth rinses to prevent tooth decay. Epidemiological findings have demonstrated that exposure to fluoride induced neurodevelopmental toxicity, developmental neurotoxicity, and motor disorders. The neuroprotective effect of clofibrate, a peroxisome proliferator-activated receptor alpha agonist, was investigated in the present study. Forty male Wistar rats were used for this study and randomly grouped into 10 rats per group as control, sodium fluoride (NaF) alone (300 ppm), NaF plus clofibrate (250 mg/kg), and NaF plus lisinopril (10 mg/kg), respectively, for 7 days. NaF was administered in drinking water while clofibrate and lisinopril were administered by oral gavage. Markers of neuronal inflammation and oxidative stress, acetylcholinesterase activity, and neurobehavioral (hanging wire and open field) tests were performed. Immunohistochemistry was performed on brain tissues, and they were probed with glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, and cerebellar Ca2+ -binding protein calbindin-D28k. The results showed that NaF significantly increased of oxidative stress and neuroinflammation and inhibited AChE activity. Immunostaining showed reactive astrocytes, microgliosis, loss of dendritic spines, and arborization in Purkinje cells in rats administered only NaF. Neurobehavioral results showed that cotreatment of NaF with clofibrate improved muscular strength and locomotion, reduced anxiety, and significantly reduced astrocytic count. Overall, cotreatment of NaF with either clofibrate or lisinopril showed neuroprotective effects by mitigating neuronal inflammation and oxidative and motor incoordination. Hence, clofibrate could be seen as a novel drug candidate against neurodegeneration and motor disorders.

The ethanol leaf extract of Andrographis paniculata blunts acute renal failure in cisplatin-induced injury in rats through inhibition of Kim-1 and upregulation of Nrf2 pathway.

Background Cisplatin (CP) is a novel drug of choice in the treatment of cancer but its major limitation is nephrotoxicity, which is dose limiting. Andrographis paniculata (AP) is a common Indian dietary component. It is well known for its medicinal properties. This present study investigated the nephroprotective effect of ethanol leaf extract of Andrographis paniculata (EEAP) on CP-induced nephrotoxicity. Methods CP was used to induce nephrotoxicity in male Wistar rats to study the effect of EEAP on renal damages using hematological parameters, biochemical parameters, histology, and immunohistochemistry studies. Results The effects of EEAP were determined by CP-induced changes in different kidney tissue on antioxidant enzymes, markers of oxidative stress, serum creatinine, and urine parameters. Administration of EEAP (200 mL/kg and 400 mg/kg orally), prior to and following a single dose CP treatment (10 mg/kg i.p), significantly mitigated the CP-induced decrease in antioxidant enzymes, and increase in markers of oxidative stress, serum creatinine, and urinary protein. On histopathological examination of the kidney tissue, there was severe glomerular degeneration and infiltration of inflammatory cells in CP only treated rats, mild glomerular degeneration, and infiltration of inflammatory cells in EEAP pre-treated rats. Furthermore, EEAP activated Nrf2 and mitigated Kim-1 pathways in CP-induced nephrotoxicity. Conclusions The results showed the protective effect of EEAP against CP-induced nephrotoxicity.

Cardioprotective Effects of Curcumin-Nisin Based Poly Lactic Acid Nanoparticle on Myocardial Infarction in Guinea Pigs.

Myocardial infarction (MI) is the most prevalent cause of cardiovascular death. A possible way of preventing MI maybe by dietary supplements. The present study was thus designed to ascertain the cardio-protective effect of a formulated curcumin and nisin based poly lactic acid nanoparticle (CurNisNp) on isoproterenol (ISO) induced MI in guinea pigs. Animals were pretreated for 7 days as follows; Groups A and B animals were given 0.5 mL/kg of normal saline, group C metoprolol (2 mg/kg), groups D and E CurNisNp 10 and 21 mg/kg respectively (n = 5). MI was induced on the 7th day in groups B-E animals. On the 9th day electrocardiogram (ECG) was recorded, blood samples and tissue biopsies were collected for analyses. Toxicity studies on CurNisNp were carried out. MI induction caused atrial fibrillation which was prevented by pretreatment of metoprolol or CurNisNp. MI induction was also associated with increased expressions of cardiac troponin I (CTnI) and kidney injury molecule-1 (KIM-1) which were significantly reduced in guinea pig's pretreated with metoprolol or CurNisNp (P < 0.05). The LC50 of CurNisNp was 3258.2 µg/mL. This study demonstrated that the formulated curcumin-nisin based nanoparticle confers a significant level of cardio-protection in the guinea pig and is nontoxic.

Oxidative stress changes observed in selected organs of African giant rats (Cricetomys gambianus) exposed to sodium metavanadate.

Vanadium is a contaminant of crude oil that released into the atmosphere through burning of fossil fuels. The mechanism by which it exerts toxic influences had not been fully elucidated in African giant rat (AGR). This study investigates the mechanisms of sodium metavanadate (SMV) induced oxidative stress in AGR. A total of 24 adult male AGR weighing 600-850 g were used. Animals were randomly divided into six groups. Groups 1, 3 and 5 served as control while groups 2, 4 and 6 were treated with intraperitoneal 3 mg/kg body weight of SMV for 3, 7 and 14 days, respectively. Serum, brain, liver, testes, kidneys, spleen and lungs were harvested for biochemical assays. SMV induced significant increase in malondialdehyde, hydrogen peroxide, sulfhydryl (total thiol) and protein carbonyl levels but decreased non-protein thiol levels in tissues accessed. A significant decrease was observed in glutathione-S-transferase (GST), superoxide dismutase (SOD), reduced glutathione (GSH) and glutathione peroxidase (GPx) levels in SMV treated rats compared to controls. Serum myeloperoxidase, xanthine oxidase and Advanced Oxidative Protein Products (AOPP) were markedly increased while nitrous oxide levels were significantly decreased in all treated groups. SMV exposure to AGR induced oxidative stress through generation of reactive oxygen species (ROS) and depletion of the antioxidant defence system. These conditions could become severe with prolonged exposure.

The Protective Effect of the Ethanol Leaf Extract of Andrographis Paniculata on Cisplatin-Induced Acute Kidney Injury in Rats Through nrf2/KIM-1 Signalling Pathway.

The ethanol leaf extract of Andrographis paniculata was used to ameliorate the renal toxicity induced by cisplatin in 28 rats divided into four groups of seven rats per group. Group A received normal saline for the duration of the experiment. Group B animals were treated with cisplatin (10 mg/kg i.p) on day 1 and 3 days after received normal saline for the next 7 days while groups C and D animals also received 10 mg/kg dose of cisplatin on day 1 but after 3 days were then respectively treated with 200 and 400 mg/kg doses of the extract of Andrographis paniculata for the remaining 7 days through oral administration. Serum chemistry was used for the determination of markers of oxidative stress, anti-oxidant enzymes, serum biomarkers etc. Histopathology and immunohistochemistry were also carried out. Results showed that all oxidative stress markers assayed were significantly increased in group B animals but reverse is the case for groups C and D. On the other hand, antioxidant enzymes assayed experienced significant increase for groups C and D while these parameters experienced significant decrease for group B animals. Histopathology showed severe infiltration of inflammatory cells into renal tissues of group B animals whereas for groups C and D animals, only moderate glomerular degeneration was noted. In immunohistochemistry, while there is higher expression of KIM-1 for group B, there was a lower expression in groups C and D. Again, there was lower expression of Nrf2 for group B but higher expressions in groups C and D animals.

Polyphenol-Rich Fraction of Parquetina nigrescens Mitigates Dichlorvos-Induced Cardiorenal Dysfunction Through Reduction in Cardiac Nitrotyrosine and Renal p38 Expressions in Wistar Rats.

Parquetina nigrescens is commonly used to treat diseases in humans and animals in developing countries, including Nigeria. This study evaluates the effects of its polyphenol-rich fraction (prf) on dichlorvos-induced cardio- and renal toxicity. There were several factors assessed during this study, including cardiac and renal markers, serum myeloperoxidase and xanthine oxidase, and electrocardiograph (ECG) changes. The changes in electrocardiograph (ECG) were recorded. Immunohistochemistry of cardiac and renal p38 and nitrotyrosine was determined. Dichlorvos exposure caused a significant decrease in L-glutathione (reduced glutathione) and other antioxidant enzymes with increases in malondialdehyde, myeloperoxidase, advanced oxidation protein products, and protein carbonyl levels. It also brought about alterations in microanatomy of the heart and kidneys accompanied by increases in serum creatinine and urea levels. Exposure to dichlorvos induced prolonged QRS interval and shortened QT durations in rats. Immunohistochemistry revealed lower expressions of cardiac nitrotyrosine and renal p38 (mitogen-activated protein kinase; MAPK) in rats treated with prf of P. nigrescens. Combining all, prf of P. nigrescens demonstrated antioxidant as well as protective properties in the heart and kidneys of rats exposed to dichlorvos. It ameliorated dichlorvos-induced cardio- and nephrotoxicity giving credence to its use in ethnomedicine.

Ameliorative effect of gallic acid on doxorubicin-induced cardiac dysfunction in rats.

BACKGROUND: The use of doxorubicin (DOX) as an antineoplastic agent has been greatly limited because of the myriad of toxic sequelae associated with it. The aim of this study was to assess the protective effects of gallic acid (GA) on DOX-induced cardiac toxicity in rats. METHODS: Sixty male rats (Wistar strain) were used in this study. They were divided into six groups (A-F) each containing 10 animals. Group A was the control. Rats in Groups B, C, and D were treated with DOX at the dosage of 15 mg/kg body weight i.p. Prior to this treatment, rats in Groups C and D had been treated orally with GA for 7 days at the dosage of 60 and 120 mg/kg, respectively. Animals from Groups E and F received only 60 and 120 mg/kg GA, respectively, which were administered orally for 7 days. RESULTS: The exposure of rats to DOX led to a significant (p<0.05) decrease in the cardiac antioxidant defence system and elevation of creatine kinase myocardial band and lactate dehydrogenase. The electrocardiography results showed a significant decrease in heart rate, QRS, and QT-segment prolongation. GA alone improved the antioxidant defence system. CONCLUSIONS: The GA pretreatment significantly alleviated GA-associated ECG abnormalities, restored the antioxidant status and prevented cardiac damage.

Phytochemical screening, safety evaluation, anti-inflammatory and analgesic studies of the leaf extracts of Sterculia tragacantha.

BACKGROUND: Sterculia tragacantha (Sterculiaceae) is used in the treatment of boils, diarrhea, dyspepsia, fever, gonorrhea, snake bite, syphilis, and tapeworm in some West African nations. This study is to investigate its anti-inflammatory and analgesic activities since the plant is being used to treat fever. METHODS: Fresh leaves of the plant were collected and dried at room temperature and pulverized into powder form and 200 g of this powder was dissolved first in hexane for 72 h and the extract was filtered and the filtrate was concentrated while the substrate was further dissolved in chloroform, ethyl acetate and methanol at different times and similar procedure adopted as for the hexane. The organic solvents were used based on order of increasing polarity. Graded concentrations of the solvent extracts were prepared and used for the study. Pilot toxicity test was carried out to determine safety dose using hematology and serum chemistry as indices of toxicity. Thereafter anti-inflammatory and analgesic studies were conducted using standard tests such as carrageenan, histamine-induced-edema, tail flick test and acetic writhing test. Phytochemical screening of the plant was also conducted. RESULTS: Phytochemical screening of the powdered material showed that alkaloid, flavonoid and reducing sugar were present while tannin, cardiac glycosides, saponins and anthraquinones were absent. Pilot toxicity test using aqueous extract at 100 mg/mL concentration showed that no mortality was recorded although the animals that received 3,000 mg/kg dose exhibited slight dullness after 48 h. No significant changes were also observed for the packed cell volume, hemoglobin, white blood cell counts, platelet counts, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, blood urea nitrogen, albumin, globulin except for the 200 and 3,000 mg/kg doses that caused significant increase in the level of total protein. The n-hexane, chloroform, ethyl acetate, and methanol extracts of S. tragacantha and indomethacin produced significant (p<0.05) inhibition of paw edema compared with the control using histamine and carrageenan methods of paw edema induction. There was significant (p<0.05) reduction in writhing movements at 100 mg/kg and 200 mg/kg of n-hexane, chloroform, and ethyl acetate leaf extracts of S. tragacantha and indomethacin (10 mg/kg) when compared to the control. This effect using tail flick test was not as effective when compared to the writhing test. CONCLUSIONS: The different leaf extracts of S. tragacantha exhibited anti-inflammatory and analgesic properties and they are also safe for medicinal use.

Anti-inflammatory and antinociceptive activities of the aqueous leaf extract of Phyllanthus amarus Schum (Euphorbiaceae) in some laboratory animals.

BACKGROUND: Phyllanthus amarus has a history of use in Ayurvedic medicine for over 2000 years as well as a wide variety of traditional applications and has gained popularity in many continents as a herbal remedy; hence, it is being assessed for its safety potential and anti-inflammatory and analgesic properties in some laboratory animals. METHODS: Standard phytochemical methods were used to test for the presence of phytoactive compounds in the plant. Acute toxicity testing was carried out in mice to determine safe doses for the extract. The anti-inflammatory activity of the leaf extract of this plant was assessed using carrageenan-induced and histamine-induced paw edema. The analgesic effect was determined using the acetic acid writhing method as well as formalin test. RESULTS: The extract at 100 and 200 mg/kg body weight reduced significantly, the formation of edema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract showed a good analgesic effect characterized by reduction in the number of writhes when compared to the control. The extract caused dose-dependent decrease of licking time in rats injected with 2.5% formalin, signifying its analgesic effect. These results were also comparable to those of ibuprofen, the reference drug used in this study. CONCLUSIONS: The plant extract reduced significantly the formation of edema induced by carrageenan and histamine as well as reducing the number of writhes in acetic acid-induced writhing models and dose-dependent decrease of licking time in rats injected with 2.5% formalin. The results have validated the basis for the traditional use of P. amarus as a medicinal plant.

Anti-inflammatory and analgesic activities of the aqueous extracts of Margaritaria discoidea (Euphorbiaceae) stem bark in experimental animal models

Margaritaria discoidea is a medicinal plant used for the treatment of various body pains in Central, Eastern and Southern Africa. The aqueous extract of its stem bark was investigated for its anti-inflammatory and analgesic activities in animal models. The extract at 50, 100 and 200mg/kg body weight reduced significantly the formation of oedema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract had a good analgesic effect characterized by a reduction in the number of writhes when compared to the control. Similarly, the extract caused dose-dependent decrease of licking time and licking frequency in rats injected with 2.5% formalin. These results were also comparable to those of indomethacin, the reference drug used in this study. Acute toxicity test showed that the plant may be safe for pharmacological uses. This study has provided some justification for the folkloric use of the plant in several communities for conditions such as stomachache, pain and inflammations. Rev. Biol. Trop. 57 (4): 1193-1200. Epub 2009 December 01.

Margaritaria discoidea es una planta medicinal usada para el tratamiento de varios dolores corporales en la parte sur, central y oriental de África. Se investigaron las propiedades analgésicas y antiinflamatorias de la extracción acuosa de la corteza de su tallo en modelos animales. Los extractos de 50, 100 y 200mg/kg de peso corporal redujeron significativamente la formación del edema inducido por la carragenina y la histamina. En el modelo de contracción abdominal inducida por ácido acético, el extracto mostró un buen efecto analgésico caracterizado por la reducción en el número de contracciones en comparación con el grupo control. El extracto causó una disminución dependiente de la dosis del tiempo y la frecuencia de lamido en las ratas inyectadas con formalina al 2.5%, lo cual evidencia su efecto analgésico. Estos resultados fueron comparables con los de la indometacina, la droga de referencia usada en este estudio. La prueba de toxicidad aguda mostró que la planta podría ser segura para usos farmacológicos. Este estudio proporciona justificación para el uso folclórico de esta plata en varias comunidades, con el objetivo de tratar padecimientos tales como dolor de estómago, dolor e inflamaciones.

Assessment of the medicinal potentials of the methanol extracts of the leaves and stems of Buddleja saligna.

BACKGROUND: Buddleja saligna Willd (Loganiaceae) is a small to medium-sized evergreen tree; trunk short, often gnarled and crooked; crown dense, rounded or domed-shaped; foliage greyish green. The wild olives are traditionally used to lower blood pressures in many parts of the world. In southern Africa, bark and leaf decoctions are used to treat colic, coughs, colds, sore eyes, urinary problems and as purgatives. METHODS: The antibacterial, antioxidant activities and phenolic contents of the methanol extracts of the leaves and stems of Buddleja saligna were evaluated using in vitro standard methods. Spectrophotometry was the basis for the determinations of total phenol, total flavonoids, flavonols, and proanthocyanidins. Tannins, quercetin and catechin equivalents were used for these parameters. The antioxidant activities of the leaves and stem extracts of Buddleja saligna were determined by ABTS, DPPH, and ferrous reducing antioxidant property (FRAP) methods. Laboratory isolates of 10 bacteria species which included five Gram-positive and five Gram-negative strains were used to assay for antibacterial activity of this plant. RESULTS: The antioxidant activities of the leaves as determined by the ABTS and DPPH were similar to that of the stem. The flavonoids and the flavonols contents of the leaves were higher than that of the stem but the total phenols, proanthocyanidins and FRAP activities were higher in the methanol extracts of the stem. The extracts did show activity against both Gram-positive and Gram-negative bacteria. For instance, while the methanol extract of the leaves showed good activities on all the organisms except Serratia marcescens and Pseudomonas aeruginosa at MICs of between 2.5 and 5.0 mg/ml, the extract of the stem only showed activities on Bacillus cereus, Streptococcus pyrogens and Pseudomonas aeruginosa at the same concentration. CONCLUSION: The results from this study indicate that the leaves and stem extracts of Buddleja saligna possess antioxidant properties and could serve as free radical inhibitors or scavenger or, acting possibly as primary antioxidants. Although, the antibacterial properties of Buddleja saligna are not as effective as the standard drugs-Chloramphenicol and Streptomycin, they still possess some activity against bacterial strains used in this study. Buddleja saligna may therefore be a good candidate for functional foods as well as pharmaceutical plant-based products.

Anti-inflammatory and analgesic activities of the aqueous extracts of Margaritaria discoidea (Euphorbiaceae) stem bark in experimental animal models.

Margaritaria discoidea is a medicinal plant used for the treatment of various body pains in Central, Eastern and Southern Africa. The aqueous extract of its stem bark was investigated for its anti-inflammatory and analgesic activities in animal models. The extract at 50, 100 and 200mg/kg body weight reduced significantly the formation of oedema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract had a good analgesic effect characterized by a reduction in the number of writhes when compared to the control. Similarly, the extract caused dose-dependent decrease of licking time and licking frequency in rats injected with 2.5% formalin. These results were also comparable to those of indomethacin, the reference drug used in this study. Acute toxicity test showed that the plant may be safe for pharmacological uses. This study has provided some justification for the folkloric use of the plant in several communities for conditions such as stomachache, pain and inflammations.

Anti-inflammatory and analgesic activities of the aqueous extract of Acacia karroo stem bark in experimental animals.

The aqueous extract of the stem bark of Acacia karroo Hayne was investigated for its anti-inflammatory and analgesic activities in animal models. The extract at 100 and 200 mg/kg reduced significantly the formation of oedema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract showed a good analgesic effect characterized by a significant reduction in the number of writhes with two doses (100 and 200 mg/kg) used when compared to the untreated control group. In the tail immersion test, the extract at the doses used (100 and 200 mg/kg) increased reaction time to pain after 30 min. of oral administration of the extract. Indomethacin at 10 mg/kg served as reference drug in all these tests. The results gave a scientific basis to the traditional uses of Acacia karroo mainly for wound poultices, eye treatments and cold remedies.

Antibacterial and antioxidant properties of the methanol extracts of the leaves and stems of Calpurnia aurea.

BACKGROUND: In South Africa, Calpurnia aurea (Ait.) Benth is used to destroy lice and to relieve itches, to destroy maggots and to treat allergic rashes, particularly those caused by caterpillars. Antioxidants play an important role protecting against damage by reactive oxygen species. Plants containing flavonoids have been reported to possess strong antioxidant properties. METHODS: The antibacterial, antioxidant activities and phenolic contents of the methanol extracts of the leaves and stems of Calpurnia aurea were evaluated using in vitro standard methods. Spectrophotometry was the basis for the determinations of total phenol, total flavonoids, flavonols, and proanthocyanidins. Tannins, quercetin and catechin equivalents were used for these parameters. The antioxidant activities of the stem extract of Calpurnia aurea were determined by ABTS, DPPH, and ferrous reducing antioxidant property (FRAP) methods. Laboratory isolates of 10 bacteria species which included five Gram-positive and five Gram-negative strains were used to assay for antibacterial activity of this plant. RESULTS: The results from this study showed that the antioxidant activities of the stem extract of Calpurnia aurea as determined by the total phenol, flavonoids, and FRAP methods were higher than that of the leaves. On the other hand, the leaf extract of the plant has higher level of total flavonols and proanthocyanidins. The leaf extract also has higher radical scavenging activity as shown in 1, 1-Diphenyl-2-picrylhydrazyl (DPPH), and 2,2¿-azinobis-3- ethylbenzothiazoline-6-sulfonic acid (ABTS) assay. The leaf extract showed activity against seven of the bacterial organisms. CONCLUSION: The results from this study indicate that the leaves and stem extracts of Calpurnia aurea possess antioxidant properties and could serve as free radical inhibitors or scavenger or, acting possibly as primary antioxidants. Although, the antibacterial properties of Calpurnia aurea are not as effective as the standard drugs- Chloramphenicol and Streptomycin, they still possess some activity against bacterial strains used in this study. Calpurnia aurea may therefore be a good candidate for functional foods as well as pharmaceutical plant-based products.

Antioxidant activities and phenolic contents of the methanol extracts of the stems of Acokanthera oppositifolia and Adenia gummifera.

BACKGROUND: Acokanthera oppositifolia Lam (family: Apocynaceae) is a shrub or small tree with white latex, and the leaves of this plant are used in the form of a snuff to treat headaches and in infusions for abdominal pains and convulsions and septicaemia. Adenia gummifera Harv of the family Passifloraceae is a distinctive woody climber whose infusions are used as emetics and are said to help with some forms of depression. Lipid peroxidation has gained more importance today because of its involvement in pathogenesis of many diseases. Free radicals are the main agents in lipid peroxidation. Antioxidants thus play an important role of protecting the human body against damage by the free radicals. Plants containing phenolic compounds have been reported to possess strong antioxidant properties. METHODS: The antioxidant activities and phenolic contents of the methanol extracts of the stems of Acokanthera oppositifolia and Adenia gummifera were evaluated using in vitro standard procedures. Spectrophotometry was the basis for the determinations of total phenol, total flavonoids, flavonols, and proanthocyanidins. Tannins, quercetin and catechin equivalents were used for these parameters. The antioxidant activities of the stem extract of Acokanthera oppositifolia were determined by the 2,2'-azinobis-3- ethylbenzothiazoline-6-sulfonic acid (ABTS), 1,1-Diphenyl-2-picrylhydrazyl (DPPH), and ferrous reducing antioxidant property (FRAP) methods. RESULTS: The results from this study showed that the antioxidant activities of the stem extract of Acokanthera oppositifolia as determined by the 1,1-Diphenyl-2-picrylhydrazyl (DPPH), and ferrous reducing antioxidant property (FRAP) methods, were higher than that of Adenia gummifera. The levels of total phenols and flavonols for A. oppositifolia were also higher. On the other hand, the stem extract of Adenia gummifera had higher level of total flavonoids and proanthocyanidins than that of Acokanthera oppositifolia. The 2, 2'-azinobis-3- ethylbenzothiazoline-6-sulfonic acid (ABTS) activities of the 2 plant extracts were similar and comparable to that of BHT. CONCLUSION: Thus, the present results indicate clearly that the extracts of Acokanthera oppositifolia and Adenia gummifera possess antioxidant properties and could serve as free radical inhibitors or scavengers, acting possibly as primary antioxidants. This study has to some extent validated the medicinal potential of the stems of Acokanthera oppositifolia and Adenia gummifera.