Natural durability of Cedrus atlantica wood related to the bioactivity of its essential oil against wood decaying fungi

Abdelwahed Fidah,Mohsine Ziani,Bousselham Kabouchi,Abderrahim Famiri,Mohamed Rahouti,Mohamed Aberchane,Noura Salhi

doi:10.4067/s0718-221x2016005000049

Abstract

The Atlas cedar, Cedrus atlantica is a resinous species of Pinaceae originated from North Africa and well known for its noble timber. This work was conducted to assess the natural durability of its wood, to study the chemical composition of essential oil extracted from its sawdust wood and to test the bioactivity of this essential oil against four wood decaying fungi: Gloeophyllum trabeum, Oligoporus placenta, Coniophora puteana and Trametes versicolor. The assessment of natural durability of wood was conducted according to the methods described in the European standards, CEN/TS 15083-1 and NF EN 350-1. Mass losses of wood specimens, after 16 weeks of exposure to fungi attack, in laboratory test, showed that Cedrus atlantica wood is very durable to durable against wood decay fungi attack. The extraction of essential oil from sawdust by hydro-distillation yielded about 3,35% and the chemical analysis of this essential oil by GC-MS showed that E-γ-Atlantone (19,73%); E-α- Atlantone (16,86%), 5-Isocedranol (11,68%); 9-iso-Thujopsanone (4,45%); Cedranone (4,13%) and Z α- Atlantone (4,02%) were the main major identified components. The antifungal activity tested by the direct contact technique on agar medium showed a strong inhibition of wood decaying fungi, especially Gloeophyllum trabeum inhibited at 1/1000 v/v concentration.

Highlights

The genus Cedrus, belonging to the family of Pinaceae, includes four species: Cedrus atlantica, C. libani, C. brevifolia and C. deodora
C. atlantica wood specimens showed no apparent decay by the three tested wood decaying fungi and mass losses are below 4,8 % (Table 2)
A correspondence is established between natural durability classes and the risk of biological attacks classes (NF EN 460 Standard, 1994)

Summary

Introduction

The genus Cedrus, belonging to the family of Pinaceae, includes four species: Cedrus atlantica, C. libani, C. brevifolia and C. deodora. In Morocco, the Atlas cedar covers an area of approximately 132000 hectares located mainly in the Middle Atlas. It annually provides between 80000 and 100000 m3 of wood logs intended for sawing and veneer. C. atlantica wood is ranked among half-heavy to heavy woods, with basic density, at 12 % moisture, of 530 kg/m3; a total volumetric shrinkage of approximately 11,26%. It has a better dimensional stability and has an easy drying, with axial compression strength of 48,8 MPa, shear strength of 13,6 MPa; a static flexural modulus of 10101 MPa and a rupture under static bending modulus of 94 MPa (El Azzouzi and Keller 1998). Its heartwood is very durable to durable against wood-decay fungi (Brunetti et al 2001)

Methods

Results

Conclusion