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Scandenone (warangalone) is a flavonoid found in Erythrina species and other plant genera. It has been connected with physiological processes in insects, human cells and bacteria. In this article, an overview of the biological importance of this compound is provided. A detailed analysis of its crystal structure and antibacterial properties were investigated. The experimental study was supplemented using density functional theory (DFT) and quantitative structure-activity relationship (QSAR) methods. Scandenone proved most potent against Mycobacterium smegmatis (mc2 155) with MIC below 1 μg/mL. In general, it was more potent against Gram-positive bacteria. Scandenone may be a potential tuberculosis medication.

Three processes were used for the extraction of total phenol and total flavonoid contents of Anacardium occidentale L. and to determine its antioxidant activity. Whatever the extraction process was, the total flavonoid and total phenol contents were of the same order. With the microwave-assisted extraction (MAE), 666.07 mg gallic acid equivalent (GAE)/100 g dry matter (DM) of total phenol content was obtained from the stem barks, 601.71 mg/100 g DM from the leaves and 69.18 mg quercetin equivalent (QE)/100 g DM from the nuts of cashew. With Soxhlet extraction, 605.47 mg GAE/100 g DM of total phenol content was obtained from the stem barks, 600.38 mg GAE/100 g DM from the leaves, 609.13 mg GAE/100 g DM from the nuts of cashew, then 67.13 mg QE/100 g DM of the total flavonoid content was obtained from the stem barks, 65.13 mg QE/100 g DM from the leaves and 61.75 mg QE/100 g DM from the nuts of cashew. Finally, with mechanical agitation, 608.52 mg GAE/100 g DM of total phenol content was obtained from the stem barks, 604.85 mg GAE/100 g DM from the leaves and 593.47 mg GAE/100 g DM from the nuts of cashew; 76.86 mg QE/100 g DM of total flavonoid content was obtained from the stem barks, 76.31 mg QE/100 g DM from the leaves and 70.39 mg QE/100 g DM from the nuts of cashew. The antioxidant tests revealed that MAE gave better anti-oxidant activity and more phenolic compounds. Key words: Processes of extraction, antioxidant activity, Anacardium occidentale, microwave-assisted extraction.

Background: The objectives of this study are to investigate the antimicrobial, antioxidant and antiradical properties of methanol extract of the stem and root bark of Trichilia emetica on a model of free radical-induced membrane damage. Methodology: p-Iodonitrotetrazolium chloride colorometric assay was used to determined bacterial and yeast susceptibility to plant samples. The antioxidant activity was evaluated using DPPH radical, hydroxyl radical, nitric oxide scavenging and reducing power assays. The cellular oxidative stress was evaluated through haematolysis and haematoprotective assays. Results: The stem bark extract revealed a great antibacterial activity against 62.5% of bacteria strains tested with minimal inhibitory concentrations ranging from 32 to 64 µg/ml. The IC50 value the stem and root bark extracts were 9.68 ± 0.75 and 10.05 ± 0.86 μg/ml, 9.98 ± 0.52 and 200.49 ± 3.40 μg/ml, 45.92 ± 2.45 and 4081 ± 212 μg/ml, respectively for DPPH radical, hydroxyl radical and reducing ability assays. Both extracts exhibited concentration dependent haemolysis of sheep red blood cells (RBCs). Stem and root bark extracts (25 µg/ml) diminish respectively by 95.9 and 85.68% hydrogen peroxide-mediated cytotoxicity. Conclusion: Our data reveals that antibacterial and antioxidant activities of the methanol extract of Trichilia emetica stem bark were better than that of root bark.

Erythrina droogmansiana is used in traditional medicine in Cameroon to treat epilepsy, insomnia and headaches. From this plant, many secondary metabolites are extracted including alcaloids, tannins, flavonoids, etc. Amongst the flavonoid, abyssinone V-4’ methyl ether is used in this manipulation. Animal models of epilepsy: pentylenetetrazol (PTZ), picrotoxine (PIC) and pilocarpine (PILO)-induced convulsions or turning behavior were used to evaluate anticonvulsant activity while diazepam-induced sleep test was used to evaluate sedative activity of the extract. Four doses of extracts were used for each group test (12.5, 25, 50 and 100 mg/kg). Abyssinone V-4' methyl ether protected 100% of mice against the convulsions induced by the pentylenetetrazole at the dose of 100 mg/kg. Abyssinone V-4’ methyl ether protected 100% of mice at the doses of 25 and 100 mg/kg and 80% at the doses of 12.5 and 50 mg/kg against generalized convulsions induced by picrotoxine. This flavonoid protected 100% of mice at the doses 25 and 50 mg/kg and 80% at the doses of 12.5 mg/kg against generalized convulsions induced by pilocarpine. Moreover, for the test of induction of convulsions by pilocarpine, Abyssinone V-4’ methyl ether protected 100% of mice at doses of 25 and 50 mg/kg and 71.43% at the doses of 12.5 and 100 mg/kg against death after 1h and 24h respectively. Abyssinone V-4’ methyl ether has anticonvulsivant properties and not sedative properties. These results explain the use of Erythrina droogmansiana to treat epilepsy.

In this work we present the heat generated by the super magnetic particle, the waste prevent from the plasmodium degradation. The hemozoin behaviour due to electromagnetic field applied on it will be used as a sensitive method for malaria diagnosis. Hemozoin presents its self in the form of a crystal and which constitutes a pigment synthesised by the malaria parasite with the aim of annihilating the toxic effect ofhematine. In effect, after contamination the plasmodium dwells inside the red blood cells of the host so as to feed itself with the amino-acids obtained by degradation of hemoglobin. But during this “meal” the parasite liberates a waste product in the form of a complex made of porphyrin and iron. In order to prevent that noxious effect, the plasmodium polymerizes the complexes of porphyrin inside a digestive vacuole to finally produce a crystal of a hemozoin not toxic for him. This particle is previously paramagnetic because of the presence of iron in the red blood cells. This paper proposes the modeling of magnetic field effect of hemozoin for malaria detection. The potential effect of the cyclically activated magnetic field was modeled using a thermodynamic framework. Then at the end, generation and diffusion of heat due to the presence of constant cyclically magnetic field have been determined. These to prove how the pull or push forces between the particles of Hemozoin are demonstrated by producing the heat. The energy inside the particle is also taken into consideration in the cell while doing the diagnosis of malaria.

The aim of this study was to isolate compounds from Cameroonian propolis extracts and to test their antibacterial activities against bacteria isolated from carcass at the Yaound� slaughterhouse. The n-hexane, ethyl acetate and ethanol extracts of propolis samples from Ngaoundal and Tala-Mokolo were separated by successive silica gel column chromatography to give six triterpenes. Their structures were determined as 25-cyclopropyl-3β-hydroxyurs-12-ene (7), cycloart-3β-hydroxy-12, 25(26)-diene (8), lup-20(29)-en-3-one (9), olean-12-en-3β, 28-diol (10), lup-20(29)-en-3β-oate (13) and 3β-hydroxylup-20(29)-ene (14). Compounds 7 and 8 were new triterpene derivatives while 10 and 13 were isolated for the first time from propolis. The structures of all the compounds were established on the basis of spectroscopic analysis. Phytochemical screening of the methanol extract (5) revealed the presence of alkaloids, reducing compounds, coumarins, saponins and tannins accounting for its broad spectrum antibacterial activities. The six isolated compounds and crude extracts were tested for antimicrobial activity against some Gram negative bacteria. The methanol extract (5) of propolis samples was active against Escherichia coli and Pseudomonas aeruginosa (MIC: 0.2 mg/ml) whereas the isolated compounds 7, 8 and 10 exclusively exhibited antimicrobial activity against Salmonellas pp (MIC: 0.1-0.15 mg/ml). The MIC values of all the four propolis products were greater than that of the standard drug (Amoxicillin): 0.1-0.2 mg/ml versus 0.4 mg/ml. Nevertheless, further pharmacological and toxicity studies on experimental animals are necessary to establish the safety of the propolis products for its use as topical antimicrobial agents.

The objective of this study was to evaluate in vitro synergy of extracts from Picralima nitida, Cylicodiscus gabunensis, Cassia arereh and Trichilia emetica and known antimicrobial agents against clinical isolate of vibrio cholerae. The in vitro antibacterial activity of plant-extracts was evaluated alone and in combination with standard antibiotics against Vibrio cholerae using disc-diffusion and microdilution method. Only antibiotics acting by inhibiting proteins synthesis shown strong bactericidal activity with inhibition zone diameter ranging from 11 ± 0.0 to 26 ± 0.6 mm. we also noticed that methanolic extract of Cassia arereh and Trichilia emetica and ethyl acetate extract of Cassia arereh contain bioactive compounds. These extracts were effective anticholeric agents with MIC ranging between 12.207 and 97.656 µg/ml and MBC between 48.828 and 781.25 µg/ ml. Cassia arereh extract showed the greatest activity with MIC and MBC values of 12.207 and 48.828 µg/ ml respectively. Synergism was observed between antimicrobial agents and the best anticholeric plant-extract with significant reduction in the MICs of antibiotics against the strains tested. Administration of both compounds together resulted in an MIC ranging from 0.078 to 10 µg/ ml which represents a 2 to 16-fold reduction in the MICs of the antibiotics tested alone. This change in MIC was noticed even with antibiotics showed weak antibacterial activity.

Background Hyperlipidemia and oxidative stress are major risk factors for atherosclerosis, and all three are among the most important risk factors for cardiovascular diseases. Cassia occidentalis aqueous extract has been used in African traditional medicine for the treatment of hypertension and associated cardiovascular diseases. This study was undertaken to evaluate the hypolipidemic and anti-atherosclerotic properties of the aqueous extract of the leaves of C. occidentalis in rats with hypercholesterolemia (HC). Sixty Normocholesterolemic (NC) male rats were divided into six groups (n = 10) and fed a high-cholesterol (HC) diet for 30 days (5 groups), or normal rat chow (normal control group). The plant extract was administered to animals at the increasing dose of 240, 320 and 400 mg/kg. After 4 weeks of treatment 5 rats out of 10 were sacrificed, blood samples, aorta, liver, and fresh faecal were collected and processed for biochemical tests. The experiments were conducted under the same conditions with a group of rat treated with Atorvastatin (1 mg/kg), used positive control. The effects of C. occidentalis on weight gain, water and food consumptions, levels of serum lipids and lipoprotein lipid oxidation and stress markers in blood and liver were also examined. Results A significant body weight gain was observed in general in all the group of animals without any treatment after 4 weeks. During the treatment period, the C. occidentalis extract induced a significant increase (P