Compounds from <em>Terminalia mantaly</em> L. (Combretaceae) Stem Bark Exhibit Potent Inhibition against some Pathogenic Yeasts and Enzymes of Metabolic Significance<strong></strong>

Tchuenmogne MAT, Ngouana TK, Gohlke S, et al. Compounds from &lt;em&gt;Terminalia mantaly&lt;/em&gt; L. (Combretaceae) Stem Bark Exhibit Potent Inhibition against some Pathogenic Yeasts and Enzymes of Metabolic Significance&lt;strong&gt;&lt;/strong&gt;. Preprints. 2016.The chemical investigation of the anti-yeast methanol extract from the stem bark of Terminalia mantaly led to the isolation of seven compounds: 3-O-methyl-4-O-&amp;alpha;-rhamnopyranoside ellagic acid (1), 3-O-mehylellagic acid (2), arjungenin or 2,3,19,23-tetrahydroxyolean-12-en-28-o&amp;iuml;c acid (3), arjunglucoside or 2,3,19,23-tetrahydroxyolean-12-en-28-o&amp;iuml;c acid glucopyranoside (4), 2&amp;alpha;,3&amp;alpha;,24-trihydroxyolean-11,13(18)-dien-28-o&amp;iuml;c acid (5), stigmasterol (6), stigmasterol 3-O-&amp;beta;-D-glucopyranoside (7). Their structures were established by means of spectroscopic analysis and comparison with published data. Compounds 1-5 were tested in vitro for activity against three pathogenic yeast isolates, Candida albicans, Candida parapsilosis and Candida krusei. The activity of compounds 1, 2 and 4 were comparable to that of the reference compound fluconazole (MIC values below 32 &amp;micro;g/ml) against the three tested yeast isolates. They were also tested for inhibitory properties against four enzymes of metabolic significance: Glucose-6-Phosphate Deshydrogenase (G6PD), human erythrocyte Carbonic anhydrase I and II (hCA I and hCA II), Glutathione S-transferase (GST). Compound 4 showed highly potent inhibitory property against the four tested enzymes with overall IC50 values below 4 &amp;micro;M and inhibitory constant (Ki) &amp;lt;3 &amp;micro;M.</jats:p

Anti-plasmodial and cholinesterase inhibiting activities of some constituents of Psorospermum glaberrimum

Lenta BN, Devkota KP, Ngouela S, et al. Anti-plasmodial and cholinesterase inhibiting activities of some constituents of Psorospermum glaberrimum. Chemical &amp; Pharmaceutical Bulletin. 2008;56(2):222-226.Glaberianthrone (1), a new bianthrone was isolated from the hexane extract of the stem bark of Psorospermum glaberrimum together with thirteen known compounds: 3-geranyloxyemodin anthrone (2), friedelan-3-one (3), 3-prenyloxyemodin anthrone (4), 3-geranyloxyemodin (5), 3-prenyloxyemodin (6), friedelan-3-ol (7), acetylvismione D (8), betulinic acid (9), 2-geranylemodin (10), bianthrone A2b (11), bianthrone 1a (12), emodin (13) and 2-prenylemodin (14). The structures of the isolated compounds were established by means of spectroscopic methods. The extracts and the isolated compounds were tested in vitro for their anti-plasmodial activity against Plasmodium falciparum (chloroquine resistant strain W2) and for their acetyl- and butyryleholinesterase inhibitory properties. The n-hexane extract showed good anti-plasmodial activity against P falciparum W2 strain, with IC50 of 0.87 mu g/ml. It also exhibited 65.5% and 98.2% of acetyl- and butyrylcholinesterase inhibition at 0.2 mg/ml, respectively. Compounds 2 and 8 showed the best potencies against P falciparum W2 strain with IC50 of 1.68 mu M and 0.12 mu M, (0.66 mu g/ml and 0.054 mu g/ml) respectively. All tested compounds showed good butyrylcholinesterase inhibition activities with compound 12 displaying the best potency (IC50 9.25 +/- 0.25 mu M). All the tested compounds showed weak inhibitory activity against acetylcholinesterase