Your search resulted in 472 documents. Displaying 25 entries per page.
Screening of the efficacy of tall oils against wood decaying fungi
2004 - IRG/WP 04-30354
Tall oil is a by-product in pulping of resinous wood by the sulphate process. Tall oil contains a complex mixture of wood extractives. Some of these extractives act as natural protection against wood decaying fungi while other serve as nutrition for the fungi. This report describes a screening of the efficacy of four refined tall oils with different chemical composition on wood decaying fungi. Testing was performed as filter paper assay and mini-block assay. In the filter paper assay growth rates of the white rot fungus Coriolus versicolor and the brown rot fungus Poria placenta were inhibited by the tall oils. None of the oils caused total inhibition of the fungi but there was a clear pattern towards increased efficacy with increased portion of resin acids in the oils. Impregnated mini-blocks with approximately 200 kg/m3 retention of tall oil after leaching showed an evident effect against Coniophora puteana and Poria placenta compared to untreated control samples. However, using the criteria from EN 113 requiring less than 3% mass loss, tall oil failed. The results indicate that decay resistance of tall oil impregnated Scots pine sapwood to the retention level used in this study is comparable with the decay resistance of Scots pine heartwood. It was expected that the efficacy of the tall oils was related to chemical composition of the oils. This was confirmed for the filter paper assay where the efficacy increased with increasing amount of resin acids. However, this pattern was not found for the mini-block assay. The protective effect of the tall oils in wood seems therefore to be more related to their hydrophobic properties than to their fungicidal properties.
G Alfredsen, P O Flæte, A Temiz, M Eikenes, H Militz
Synthesis of a rosin amide and its resistance to wood decay fungi
2009 - IRG/WP 09-30517
Rosin was reacted with diethyltriamine (DETA) after being modified by acryl acid with the weight ratio of 4.5:1 and a rosin amide (RA) derivative was produced at the conditions as follows: modified rosin and DETA mole ratio of 1:3.5, dimethylbenzene as water carrying agent, reaction temperature of 160-180°C, and reaction time of 8h. The chemical structure of the product as RA was identified by FTIR and MS analysis. The anti fungal activity of its derivative was determined by paper-disc method with wood decay fungi such as Coriolus versicolor, Gloeophyllum trabeum, Aspergillus niger and Paecilomyces variot Bainier. The anti-fungal experiment results signified that the derivative is active to these fungi, especially Paecilomyces variot Bainier. Since it is produced easily from rosin, which is renewable and not expensive, RA could be a potential wood preservative. Further study is planning.
Shuangyue Li, Shujun Li, Jing Wang
Coconut shell pyrolytic oil as wood protectant against biodeterioration
2014 - IRG/WP 14-30648
Extensive research on various plant and microbial extracts has been conducted as an alternative to using synthetic or inorganic chemicals for wood protection. Development of effective and low environmental impact products and technologies for wood protection is imperative. In the present study, the efficacy of coconut shell pyrolytic oil as a wood protectant is analysed in terms of its antifungal, antiborer and termiticidal activities. The antifungal, antiborer and antitermite activity of coconut shell pyrolytic oil was assessed by BIS standards IS 4873 (Part I: 2008), IS 4873 (Part II: 2008) and IS 4833 :( 1993) respectively. Wood decay fungi namely, Tyromyces versicolor (L.) Fr. and Polyporus sanguineus (L.) G. Mey (white rot) Polyporus meliae (Undrew.) Murrill. and Oligoporus placenta (Fr.) Gilb. & Ryvarden( brown rot) were used to determine the antifungal effect of coconut shell pyrolytic oil. The antiborer effect of coconut shell oil was indicated by its efficacy in protecting the treated test blocks against Lyctus africanus lesne. Grave yard test was performed to determine the termiticidal activity of coconut shell pyrolytic oil against the termite fauna identified at the test yard Odontotermes horni (Wasmann), Odontotermes obesus (Rambur), Odontotermes redemanni (Wasmann) and Microtermes obesi (Holmgren). The effectiveness of coconut shell pyrolytic oil was expressed as percentage weight loss of the treated test blocks compared to untreated blocks. It was observed that coconut shell pyrolytic oil gave better protection against wood decaying organisms. When treatment methods were compared dip treatment was found to be significantly better than brush coating method. Coconut shell pyrolytic oil has the potential to be a new wood protectant of natural origin which can replace synthetic wood preservatives in future. Being a waste bye product of coconut shell charcoal industry, its utilization as a wood protectant will be a value addition to such industries.
K S Shiny, O K Remadevi
Anti-Fungal Activity on Some Wood extracts as a Wood Protectant
2016 - IRG/WP 16-30684
In this study, six different wood barks were used, where obtained bark extracts were blended with potato-agar in order to investigate their antifungal properties. To determine the inhibition effectiveness of extractives, two different fungi; Coniophera puteana and Trametes versicolor were selected. Fungal activity was carefully observed for the duration of seven days. Following biological testing, extracts showed a significant inhibition against each fungus. Selected extract concentration is known to be more efficient on inhibition. As concentration increased, fungal growth slowed down and hindered. Bark extracts used in this study showed great efficiency against white-rot fungus, T. versicolor at low concentration. However, efficiency against fungal activity of extracts remained the same at high concentration. These bark extracts have a favorable chance to be used as a natural wood preservative according to results.
Ö Özgenç, S Durmaz
Anti-fungal activity of rutin and rutin-metal complexes as wood protectants
2017 - IRG/WP 17-30708
The anti-fungal activity of Rutin, a flavonoid, alone or complexed with copper or zinc was investigated in a petri dish test with Gloeophyllum trabeum and Trametes versicolor as the test fungi. Rutin and the Rutin-metal complexes showed significant inhibition against each fungus. Rutin-Cu and Rutin-Zn strongly inhibited the brown rot fungus, G. trabeum, while Rutin and Rutin-Zn inhibited T. versicolor. The results suggest that this flavonoid might be used for wood protection.
Li Yan, J J Morrell, Jie Zhong, Xiuzhu Mao
Some tests on ES - AS 11, a novel anti-sapstain formulation, and its properties
1987 - IRG/WP 3399
The results of some tests with the formulation ES - AS 11 are given. The formulation is an attempt to improve the performance of an anti-sapstain chemical by: 1) increasing its penetrability 2) uniquely combining its active ingredients. Very short times of treatment (dipping not longer than 5 seconds), low concentrations of active ingredients, and lower toxicological and environmental risks may be a promising result.
Preliminary note on the fungal problem of rubber wood
1983 - IRG/WP 3246
Susceptibility of rubber wood to fungal attack limits its wider utilisation. Fungal problems encountered in treating rubber wood with boron compounds by diffusion process have been discussed. Sodium pentachlorophenoxide and 2-thiocyanomethylthio benzothioazole (TCMTB) were investigated for possible control of fungal growth during diffusion storage and their performance has been reported.
An evaluation of chemical treatments for the protection of radiata pine logs from fungal degrade
1986 - IRG/WP 3377
Busan 30, Busan 1009, Mitrol PQ375. and sodium pentachlorophenoxide (NaPCP) plus have been evaluated as antisapstain treatments for the long-term protection of debarked radiata pine logs. After 3 months' winter-spring storage, treated debarked logs had less surface and internal sapstain than 'control' logs. After 6 months' storage all logs had internal sapstain and decay. Busan 30 was the most effective treatment in preventing internal degrade although 1.5% a.i. NaPCP plus 1.5% borax was more effective in preventing decay.
J A Drysdale, M E Hedley, J A Butcher
Anti-feedant activity of stilbenic components from bark of Picea glehnii against a subterranean termite, Reticulitermes speratus
2002 - IRG/WP 02-10447
Stilbenic components, one of polyphenolic groups, widely distributed in plant bodies have been known as anti-microbial agents, but not known whether to have anti-termite activities. A stilbene glucoside, isorhapontin, from the bark of Picea glehnii was examined on the anti-feedant activity against a subterranean Reticulitermes speratus. Isorhapontigenin, the aglycone of isorhapontin, induced from it by hydrolysis using ß-glucosidase was also tested for comparison. From the results of choice and no choice feeding tests using paper disks, anti-feedant activity was shown in both the compounds. Isorhapontigenin had a larger anti-feedant activity than isorhapontin.
S Shibutani, M Samejima, S Doi
Some studies on fungal deterioration of rubber wood (Hevea brasiliensis)
1980 - IRG/WP 2140
For the sreening of anti-stain chemicals trials with selected agricultural fungicides and new chemicals were carried out. Botryodiplodia theobromae, Aspergillus sp. and Penicillium sp. were used at test organisms. For testing the durability of rubber wood (Hevea brasiliensis) suitable local rotting fungi (Basidiomycetes), based on high degrading power, which may later be employed in standard tests, were isolated: Trametes corrugata, Schizophyllum commune, Lentinus blepharodes, Lenzites palisotii, Ganoderma applanatum, Fomes senex and Polyporus zonalis. Several of the fungicides screened, such as benomyl, thiram, quintozene and captafol, are effective against the blue stain fungus Botryodiplodia theobromae, at fairly low concentrations. However at the levels required, none of them is cost-effective compared sodium pentachlorophenoxide, the preservative currently used for blue stain control in rubber wood. Of the seven Basidiomycetes tested, two of them - Lenzites palisotii and Ganoderma applanatum - were shown to give a high degree of degradation in rubber wood. These species could perhaps be used as test organisms for evaluating wood preservatives in Malaysia.
A Sujan, A G Tan, M Stevens
The suitability of isothiazolone microemulsions as long term wood preservatives
1997 - IRG/WP 97-30150
Microemulsion formulations of 4,5 dichloro-2-n-octyl-4-isothiazolin-3-one were investigated to determine the leaching potential of these formulation types as well as their efficacy against decay fungi. These patented low leaching formulations exhibited good anti fungal efficacy in standard tests combined with minimal leaching of the active ingredient from the wood. The data suggests that the excellent long term efficacy ( > 10 yrs) recorded in field tests on solvent borne formulations can be repeated with these emulsion formulations. Active ingredient analysis show an excellent penetration and macrodistribution throughout the samples. Preliminary studies using various instrumental analytical techniques on active ingredient microdistribution at the cellular level show an even distribution throughout the cell wall layers. The data indicates that these microemulsion formulations are an excellent vehicle / carrier for solubilization of a water insoluble biocide, its transport and homogenous distribution into the wood without adversely effecting its permanence or efficacy in the wood during long term service.
B M Hegarty, Bing Yu, L E Leightley
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if an additional COBRA process with "Wolmanit-B-Mischung" is applied after the oscillating pressure treatment. In this way the entire cross section of spruce transmission poles is protected except for a core diameter of 30 mm.
E Graf, B Zgraggen
Anti-fungal properties of pyrolytic oils derived from softwood bark
2000 - IRG/WP 00-30218
Thermal decomposition of balsam fir and white spruce mixed bark residues at 450°C and under vacuum (< 20 kPa abs.) results in high yields of pyroligneous liquors rich in phenolic content. This vacuum pyrolysis process has been scaled-up to a pyrolysis plant with a feed capacity of 3.5 t/h of softwood bark, which is the largest plant of this type in the world. The pyrolytic aqueous condensates have been tested for their anti-fungal properties. One of the major objectives of this study was to identify which groups of chemical compounds were the most active to inhibit the growth of wood decay fungi. The fractionation of the pyrolytic aqueous phase in four distinct parts was accomplished by a liquid-liquid extraction method. The four fractions were named F1 (ether extractibles), F2 (ethyl acetate extractibles), F3 (neutral compounds) and F4 (phenolic compounds). Petri tests were conducted using two brown rot fungi (P. placenta and G. trabeum) and two white rot fungi (I. lacteus and T. versicolor). The composition of these fractions was analysed by GC/MS. Fraction F1, with concentrations of organic acids, phenols and derivatives (3.0% by weight), benzenediols (3.9% by weight), and a variety of other products (quinones, furans, etc.), was the most promising to inhibit the growth of decay fungi, while fraction F3 showed no inhibitive effect in the Petri dish agar test. C. versicolor was most sensitive to these fractions, while I. lacteus was the least. The addition of CuSO4 to the water soluble organics improved their ability against decay.
D Mourant, Dian-Qing Yang, Xiao Lu, C Roy
In situ testing the influence of melamine resins on the enzymatic activity of basidiomycetes
1999 - IRG/WP 99-30194
Waterbased methanol etherificated melamine formaldehyde resins have the potential to increase the resistance of impregnated wood against wood destroying fungi. The mechanism of the increased wood durability is not clear yet. In the present paper the possible interference of melamine resins with wood degrading enzymes of Coniophora puteana and Trametes versicolor was investigated as a possible contribution to the increased wood durability. An in situ photometric assay was used to measure the enzymatic activity against Walseth cellulose, pine sapwood as well as lignin and xylan preparations.
D Lukowsky, F Büschelberger, O Schmidt
The role of chitinase in bioprotectant activity against staining fungi
1996 - IRG/WP 96-10175
Chitin is an important structural component of the hyphae of many wood staining fungi and its disruption can lead to dramatic declines in their growth. A number of bioprotectants have been shown to produce chitinases in liquid cultures, but the role of these enzymes in bioprotection remains poorly understood. The levels of these enzymes was studied by inoculating ponderosa pine sapwood wafers with liquid cultures of either Serratia plymuthica or Trichoderma harzianum. The wafers were then inoculated with a mixture of wood staining fungi and incubated for 4 weeks at 23 to 25°C. The wafers were then evaluated for degree of stain prior to extraction and analyzed for chitinase activity. Chitinase activity appeared to increase with increasing degree of bioprotection for several isolates of Trichoderma harzianum, while the relationship was less clear with Serratia plymuthica.
J Liu, J J Morrell
The influence of fungal species and the level of decay on the mortality and feeding activity of adult Euophryum confine (Broun)
2002 - IRG/WP 02-10448
The mortality and feeding activity of adult Euophryum confine (Broun) (Coleoptera: Curculionidae) are used to establish the substrate conditions most suitable for their rearing. Weevils were allowed to feed on Pinus nigra (Arnold) sapwood blocks, either undecayed or decayed to 10% weight loss ±5% by two brown rots Coniophora puteana (Schum.:Fr.) Karst. and Serpula lacrymans (Wulf.:Fr.) Schroeter, or the white rot Fibroporia vaillantii (DC.:Fr.) Parmasto in a non-choice test for seven days at 20°C (±1°C) and 92% relative humidity ±5%. Weevils were also allowed to feed on blocks acid pre-treated to 10% (±1%) weight loss. Weevil mortality and block weight losses resulting from feeding were recorded. Those pre-treatments resulting in low mortality and high feeding activity were considered most suitable for rearing adult weevils.
M Green, A J Pitman
Detection of Anti-Fungal Sapwood Extractives in Non-Durable Scots Pine (Pinus sylvestris), Rubberwood (Hevea brasiliensis) and Jelutong (Dyera costulata)
2007 - IRG/WP 07-10634
A general laboratory bioassay method of Woodward and Pearce (1985) was adopted to detect anti-fungal activity of sapwood or heartwood extractives of 5 Malaysian hardwoods [dark red meranti heartwood (Shorea spp.), red balau heartwood (Shorea spp.), kulim heartwood (Scorodocarpus borneensis), jelutong sapwood (Dyera costulata) and rubberwood sapwood (Hevea brasiliensis), including the temperate Pinus sylvestris (Scots pine sapwood). The heartwoods of these species and Scots pine sapwood are known to be highly resistant to decay by soft-rotting Ascomycetes and anamorphic fungi (about 1-7% wood mass loss), while the sapwoods of rubberwood and jelutong had much reduced soft rot resistance (respectively 35, 32% wood mass loss) but obviously prone to sapstain and mold attack, including that of Scots pine. Crude methanol extracts of woodmeal samples of each wood species were loaded on to thin-layer chromatography plates at between 0.003 and 0.1 g fresh mass equivalent of woodmeal per spot so as to optimize resolution of separated compounds, and developed with chloroform:methanol solvent (ratio 19:1). The dried plates were sprayed with fresh fungal spores of Cladosporium cucumerinum and incubated at >90% RH for 5 days in the dark. Presence of anti-fungal compounds was revealed by white regions along the solvent transect for each extract of each species where inhibited spore germination and mycelial growth of C. cucumerinum occurred. Comparisons of anti-fungal activity of extracts between species and between sapwood and heartwood were made. Results revealed that several zones of inhibitory activity, indicated by their Rf-values, were clearly visible on chromatographic separations of methanol extracts of these 5 wood species. The inhibitory zones for 2 heartwood extracts (except kulim) did not move from the origin which was also resistant to infection. However inhibition zones were also detected for the sapwoods of rubberwood, jelutong and Scots pine against C. cucumerinum despite the known sapstain and decay susceptibility of these wood substrates. The presence of hitherto unidentified anti-fungal compounds in the sapwoods of these species may elicit limited potency or narrow spectrum protection from fungal infection and onset of stain or decay.
A H H Wong, R B Pearce
Aislamiento, identificación y evaluación enzimática de hongos de pudrición de madera de la Región de los Lagos
2008 - IRG/WP 08-10680
So far, systematic investigations have not been developed to determine the fungal diversity associated with wood in Chile. In addition, little is known about the mycoflora capabilities or their enzymatic processes in biotechnology although different research has hinted at the great potential of these microorganisms in various industrial processes. The aim of this work is to isolate, identify and enzymatically evaluate wood decay fungi present in national parks located in Chile’s Región de los Lagos. The research will be divided into three stages: isolation, identification and qualitative enzymatic evaluation of the microorganisms. A classification of the identified fungi according to the enzymatic activity observed (cellulotic, hemicelullotic, peroxidase, or laccase activities) is expected to be generated. This paper contains the research methodology and literature review of this project. En la actualidad no se han desarrollado investigaciones sistemáticas que permitan determinar la diversidad fúngica presente en maderas de Chile. Así mismo, el conocimiento acerca de sus capacidades enzimáticas y aplicabilidad en procesos biotecnológicos ha sido parcialmente desarrollado. No obstante lo anterior, diversos antecedentes muestran un gran potencial de estos microorganismos en diferentes procesos industriales. El objetivo de este trabajo es aislar, identificar y evaluar enzimáticamente los hongos de pudrición obtenidos de maderas presentes en parques nacionales ubicados en la región de los Lagos en Chile. La investigación, para el logro del objetivo planteado, será dividida en tres etapas: aislación, identificación y evaluación enzimática cualitativa de los microorganismos. A partir de este trabajo se espera conocer la micoflora existente en la zona bajo estudio. Así como también clasificar, según la actividad enzimática observada, las especies de hongos identificados.
R Ortiz, J Navarrete, C Oviedo, R Blanchette
Discovering anti-fungal agents in New Zealand native plants for use in wood protection
2009 - IRG/WP 09-10692
Extracts from Hinau (Elaeocarpus dentatus) leaves were tested in the laboratory for antifungal activity. In addition, the anatomical structure of the leaf was also examined by a combination of light and scanning electron microscopy. Chemical characterisation of the extracts and investigation into potential use of its components for wood protection is underway. A combination of light microscopy (LM) and scanning electron microscopy (SEM) proved most effective for examining the tissue composition, particularly in differentiating the distribution of lignified tissues relative to non-lignified tissues after staining freshly cut leaf sections with phloroglucinol-HCl stain, which specifically stains lignin in cell walls. In-vitro bioassay results showed antifungal activity of Hinau extracts against two brown rot fungi, Oligoporus placenta and Coniophora puteana. NMR spectra of the Hinau extracts indicated mixtures of aromatic substances, showing chemical shifts consistent with ellagitannins and/or gallotannins with minor contributions consistent with flavonoids. The identity of the bioactive component remains unknown.
C Rickard, T Singh, A Singh, R Newman
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. Isothermal calorimetry seems to be a measurement technique well suited to the study of rot fungal activity as a function of temperature and moisture content.
L Wadsö, A Pilgård, G Alfredsen
Measuring fungal cellulolytic enzyme activity in degrading wood
2011 - IRG/WP 11-10753
An enzyme assay which measures enzyme activity directly from wood will assist in the fundamental understanding of the enzyme components of the decay mechanism of rot fungi and any changes in the presence of wood protectants. At present, to measure fungal carbohydrate degrading enzyme activity in the presence of wood, two methods are used: either 1) the enzyme is measured in the growth media containing lignocellulosic material after the fungus has been allowed to utilize the cellulolytic substrate or 2) the fungus is grown on the lignocellulosic material and the enzymes are extracted using buffers after the growth period and the buffer is analyzed for enzyme activity. This research presents an enzyme assay where wood slivers are added to the assay mixture. The brown rot fungus Postia placenta was grown on wafers measuring 70mm by 23mm by 1.5mm for 12 days. The wafers were then sliced into 3mm by 1mm slivers and assayed using a micro assay using Azo-carbohydrates as substrates. The use of a 96-well microtiter plate allowed a large number of samples to be analyzed at one time with reduced reagent use. Using this assay method allows screening for enzyme activity along the length of the wafer. Our results showed detectable differences over the length of the wafer with a peak of endoglucanase activity closest to the colonization point of P.placenta. Small samples of decayed wood from the field were assayed for endoglucanase activity and the results indicate that this method has a potentially to be used to determine early decay. This assay will be useful in many research fields to gauge the presence and location of fungi and their carbohydrate degrading enzyme activity within a wood sample.
S M Duncan, J S Schilling
Triazole – based ionic liquids to protect of lignocellulosic materials against fungi
2012 - IRG/WP 12-30601
In presented paper we examined on biotic properties of novel structure of tebuconazole derivatieves: tebuconazole hydrochloride, allyltebuconazole chloride, methyltebuconazole iodide, tebuconazole dihydrocitrate. Our investigation against wood-degrading fungi were contained also the didecyldimethylammonium 3-aminotriazolate as well as didecyldime-thylammonium nitrate(V) with tebuconazole or with (tebuconazole + propiconazole). In order to confirm the structure of the new ionic liquids analyses using thin layer chromatography and proton and carbon spectra of nuclear magnetic resonance were carried out, as well as elementary analyses CHNO. The most active compound against brown and white rot fungi were precursor of ionic liquids- tebuconazole hydrochloride . The fungistatic dose (ED50) for Coniophora puteana reached 0.1 ppm, the fungitoxic dose (ED100) - 5 ppm and lethal dose (LD) - 5 ppm. The fungicidal value of didecyldimethylammonium nitrate(V) with tebuconazole for Coniophora puteana were < 0.73kg/m3 , for Trametes versicolor ranged from 0.81 kg/m3 to 1.76 kg/m3 The investigation of protic triazole-based ionic liquids demonstrated the strongest action against blue stain and mould fungi. The growth of mycelium on the surface of wood samples was inhibited in the amount of application 15 g/m2. The penetration depth into Scots pine wood Pinus sylvestris L. of didecydimethyl-ammonium nitrate(V) including the tebuconazole was reached 6.2 mm.
J Zabielska-Matejuk, J Pernak, I Frąckowiak, A Stangierska, W Przybylska, M Kot
Activities of moulds on wood as a function of relative humidity during desorption and absorption processes
2013 - IRG/WP 13-10794
Three different types of indoor moulds: Penicillium brevicompactum, primary colonizer; Alternaria tenuissima, secondary colonizer and Trichoderma harzianum, tertiary colonizer, grown on wood were measured for their activities under different relative humidity levels. The activities were measured by isothermal calorimetry. The activities of the moulds changed with the change of the relative humidity levels. The optimal relative humidity levels are different for these three moulds. The mould activities were also different from desorption to adsorption processes under the same relative humidity levels. This might be caused by the moisture hysteresis properties of wood. Therefore, besides of relative humidity, water availability also plays an important role for mould growth. Such information should be taken into account for modelling mould behaviour on building materials.
Yujing Li, L Wadsö
Activity of wood preservatives against mould fungi
2016 - IRG/WP 16-30695
The resistance of experimental and commercial wood preservatives to mould fungi was determined using a method recommended by the Building Research Institute Instruction. The research of the inhibiting actions of the growth of fungi was carried out on the Scots pine wood Pinus sylvestris L. and beech Fagus sylvatica L. The most active compounds against mould were experimental herbicidal ionic liquids and didecyldimethylammonium nitrite. Their activity was comparable to the commercial mixtures of tebuconazole with thiabendazole or with iodopropynyl butylcarbamate.The growth of mycelium on the surface of wood samples was inhibited in the amount of application 15 g m-2.
J Zabielska-Matejuk, A Stangierska
Chemical compositions and anti-termite activities of essential oils from Gabonese Canarium schweinfurthii Engl, Dacryodes buettneri Engl and Aucoumea klaineana Pierre wood resins.
2017 - IRG/WP 17-10895
Essential oil extract from resins of Canarium schweinfurthii, Dacryodes buettneri and Aucoumea klaineana woods from Cap Esterias and Oyem areas, Gabon, were prepared by Clevenger - steam distillation. The chemical compositions of these respective essential oils were analyzed by a Gas Chromatography coupled with Mass Spectrometry (GC-MS). Although monoterpenes were the main constituents of the three essential oils, each wood resins had a various essential oil yield after steam distillation process [6,92% (A. klaineana), 4,20% (C. schweinfurthii) and 13,19% (D. buettneri)] and their respective chemical compositions were slightly different. It results that monoterpenes, as α –pinene, o-cymene, alpha-phellandrene and D-limonene form the major constituents of terpenoides and phenylpropanoïdes compounds which are the most active substances against termite activity. The anti-termite activities of the three essential oils were evaluated, performing no-choice tests. 70 μL of each essential oil diluted in acetone with mass ratios of 50:50 and 25:75 [essential oil: acetone] were impregnated on Whatman papers and exposed to termite (Reticulitermes flavipes). Essential oil from Canarium schweinfurthii resin showed the strongest inhibitory activity against the termite with 100% mortality after 1 day at 50:50 and 25:75 concentrations followed by Aucoumea klaineana resin with the 100% mortality after 3 days at 50:50 and 25:75 concentrations. Finally, essential oil from Dacryodes buettneri resin showed the lowest termite resistance with 48.34 % and 58.34% mortalities after 14 days at 50:50 and 25:75 concentrations, respectively. The number of chemical components from each essential oil and their respective quantity, determined by GC-MS, are related to their anti-termite activity level.
Chemical compositions and anti-termite activities of essential oils from Gabonese Canarium schweinfurthii Engl, Dacryodes buettneri Engl and Aucoumea klaineana Pierre wood resins.