ABSTRACT
Antiaris africana belongs to the family Moraceae, it is commonly called “False Iroko” tree and one of the medicinal plants used in treatment of mental and nervous disorders in Nigeria. We have previously established the neuroprotective properties of crude extract of A. africana. The present study was thus designed to investigate the neuroprotective effect of different solvent fractions of A. africana against cyanide neurotoxicity in vitro. Cyanide induced a significant (P<0.01) inhibition of NADH succinate dehydrogenase, a key enzyme in mitochondria function as well as significant increase in oxidative stress as observed in the high level of malonedialdehyde (MDA), protein carbonyl (PC) and activity of monoamine oxidase (MAO) and decreased concentration of reduced glutathione (GSH) as compared to the control. Co-administration with different solvent fractions of A. africana (hexane fraction [HFA], dichloromethane fraction [DFA] and methanolic fraction [MFA]) significantly ameliorated the toxic effect of KCN as compared to the induced, untreated group (P<0.05). The results in this study showed that HFA (79.04% reversal of NSD inhibitory activity of KCN), DFA (63.68% and 72.6% activity against KCN induced LPO and PC respectively). However, MFA showed the best activity against GSH depletion caused by KCN (12.21%) and inhibition of MAO activity induced by KCN (94.63%). In conclusion, all the fractions possess neuroprotective activities at varying degrees against mitochondria damage by KCN. This result further substantiated the ethnomedicinal usage of A. africana and can provide novel compounds in the treatment of mitochondria-related neurodegenerative diseases.
ABSTRACT
Leaf, stem bark and root volatile oils were obtained from Antiaris africana Engl. a large attractive and medicinal deciduous timber tree (Moraceae) in 0.24%; 0.67% and 0.76% yields respectively. GC and GC-MS analyses revealed 10 compounds are responsible for leaf oil; 22 compounds make up 98.9% of the stem bark oil, while 6 compounds make-up 99.6% of root oil. 9 compounds were identified in leaf, which make-up 92.2% of it and 5 identified compounds in root represent 96.6% of it. Most abundant compounds in leaf oil are camphor (20.7%), 5-(1methylethylidene)-1,3-cyclopentadiene (16.8%), isomenthol (12.6%) and 1,3,5-trimethylbenzene (12.6%). Prominent compounds in stem bark oil are eucalyptol (19.3%), 4-methyl-1-(1methylethyl)-R-3cyclohexen-1-ol (17.4%), n-hexadecanoic acid (14.2%) and p-menth-1-en-8-ol (8.5%). Root oil is dominated by methylhexadecanoate (41.3%), 10-methyleicosane (30.4%) and methyl-13-octadecenoate (17.3%). Six other compounds in leaf oil, 18 others in stembark oil and 2 others in root oil along with above as reported are composition of Antiaris africana Engl. Leaf and stem bark oils are highly terpenic, having many interesting C10 and C15 terpenoids; Eucalyptus the most abundant compound in stem bark oil, is known to be medicinal; Presence of isomers of linalooloxide in stem bark oil is unique. Compositions of these three volatile oils are very interesting, which is scarce in literature.