Characterization of Extracts from the Bark of the Gabon Hazel Tree (Coula edulis baill) for Antioxidant,Antifungal and Anti-termite Products

Chemical composition of the bark extracts of Coula edulis was investigated to find potential antioxidant,anti-termite and antifungal compounds which can find useful applications in the fields of food,nutraceuticals,cosmetics or agrochemical.Phytochemical screening revealed the presence of several groups of active molecules such as alkaloids,polyphenols,flavonoids,saponins and sterols and/or terpenes in the different extracts.Total phenols,condensed tannins and flavonoids contents corroborated phytochemical screening.Gas chromatographymass spectrometry(GC-MS)analysis revealed compounds in dichloromethane extract different from those obtained with all the other solvents.Hexadecanoic and trans-9-octadecenoic acids,as well as stigmasterol andβ-sitosterol have been identified as the major compounds in the dichloromethane extract.Extracts obtained with acetone and toluene/ethanol mixture(2/1,v/v)indicated the presence of few amounts of fatty acids and sugars,catechin in small amount and huge amounts of phenolic acids like gallic and ellagic acids.The radical 2,2-diphenyl-1-picrylhydrazyle(DPPH)and the cationic radical 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS+)were used for evaluation of antioxidant properties of the different extracts.The dichloromethane extracts had a very low antioxidant activity,while acetone and toluene/ethanol extracts presented EC50 values similar to those of catechin and BHT used as reference antioxidant compounds.Effect of the different extracts of the bark of C.edulis on fungal growth inhibition indicated better inhibition of the mycelium growth of brown rot fungi compared to white rot fungi.Low anti-termite activities were recorded with the aqueous extracts,while stronger activities were recorded with dichloromethane,acetone and toluene/ethanol extracts.

Biomolecules of Interest Present in the Main Industrial Wood Species Used in Indonesia-A Review

As a tropical archipelagic country,Indonesia’s forests possess high biodiversity,including its wide variety of wood species.Valorisation of biomolecules released from woody plant extracts has been gaining attractive interests since in the middle of 20th century.This paper focuses on a literature review of the potential valorisation of biomolecules released from twenty wood species exploited in Indonesia.It has revealed that depending on the natural origin of the wood species studied and harmonized with the ethnobotanical and ethnomedicinal knowledge,the extractives derived from the woody plants have given valuable heritages in the fields of medicines and pharmacology.The families of the bioactive compounds found in the extracts mainly consisted of flavonoids,stilbenes,stilbenoids,lignans,tannins,simple phenols,terpenes,terpenoids,alkaloids,quinones,and saponins.In addition,biological or pharmacological activities of the extracts/isolated phytochemicals were recorded to have antioxidant,antimicrobial,antifungal,anti-inflammatory,anti-diabetes,anti-dysentery,anticancer,analgesic,anti-malaria,and anti-Alzheimer activities.Aside from these remarkable characteristics of woody plant extractives,further studies concerning the valorisation of these extractives in the fields of nutraceutical,cosmetic,bio-control,bio-stimulation,and other advanced applications would be of interest.