Study On Decay-resistant Mechanism And Antifungal Anticorrosion,Performance Of Extraction Liquid From Padauk Wood

To explore the decay-resistant mechanism of padauk wood,this study took filter method to research the antifungal performance against the fungi of coriolus versicolor and gloeophyllum trabeum of 6 kinds of extract by hot reflux extracting with distilled water and 70% ethanol from three kinds of pterocarpus wood of angola padauk,pterocarpus macrocarpus and african padauk;at the same time,took italian poplar as the selected material to do the indoor decay-resistant experiment,and used GC-MS technology to analyze its antifungal activities and decay-resistant active factor.The results are as follows:(1)6 kinds of extract was gained by extracting with distilled water and 70% ethanol from three kinds of wood,the results showed that,the rate of 70% ethanol extract was higher than the rate of distilled water extract apparently;among them,the rate of 70%ethanol extract of african padauk was the highest(28.59%),the rate of distilled water extract of pterocarpus macrocarpus was the highest(14.31%);The color of each extract was all slanted brunet department,and the state of each extract was presented solid state.(2)The antifungal performance experiment of 6 kinds of extract against 2 kinds of wood rotting fungi was mensurated with antifungal circle diameter by filter method.The results showed that,with the increase of extract concentration,the antifungal performance of two kinds of extract of angola padauk and the distilled water extract of pterocarpus macrocarpus against 2 kinds of wood rotting fungi was getting better and better,and the antifungal performance of the rest extracts was remained stable.On the whole,the antifungal performance of the 6 kinds of extract against gloeophyllum trabeum was better than that against coriolus versicolor.At the extract concentration of 4 g/L,the antifungal performance of the two kinds of extract of angola padauk against coriolus versicolor and gloeophyllum trabeum was the best.(3)The preservative retention of extract in italian poplar which had been dipped by every concentration of 6 kinds of extract was increasing with concentration increasing,and presented a good linear relationship.(4)The results of preservation experiment showed that,for coriolus versicolor,with the increase of concentration of 2 kinds of extract of angola padauk and the distilled water extract of pterocarpus macrocarpus,the rate of weight loss of sample was gradually decreasing,the degree of decay resistance reached grade?at concentration of 8g/L and16g/L;and with the increase of the rest extracts concentration,the rate of weight loss was changed little,the degree of decay resistance reached grade ? at concentration of 2g/L.For gloeophyllum trabeum,with the increase of concentration of 6 kinds of extract,the rateof weight loss of sample was gradually decreasing,the degree of decay resistance reached grade?at concentration of 4g/L,among them,the degree of decay resistance of the distilled water extract of angola padauk and african padauk reached grade?at concentration of 2g/L.(5)The antisepsis situation of sample was observed by SEM,the results showed that,both the two kinds of extract of angola padauk at concentration of 4g/L had a certain inhibition against 2 kinds of wood rotting fungi,and its antifungal performance against gloeophyllum trabeum was better than that against coriolus versicolor,that was consistent with the result of indoor preservation experiment.(6)?E of sample treated by different concentrations of extracts by 2 kinds of wood rotting fungi was increasing and ?L was decreasing with concentration increasing.The positive value of ?a and ?b showed the colour of the chips tend to red and yellow.(7)GC-MS analysis result showed that there were 57 kinds of high content and main substance in 6 kinds of extract,mainly included phenols,alcohols,aldehydes,ketones,esters,amines,alkene and aromatic compounds,etc.There were phenols,ketones,amines and aromatic compounds both appeared in 6 kinds of extract,and their relative content was both higher,so they may have bacteriostatic activity.This result cann't explain other lower content substances that also have antibacterial activity,or there is a synergy between each substance.GC-MS analysis result also showed that,6 kinds of substance was repeated in the distilled water and 70% ethanol extract of angola padauk,pterocarpus macrocarpus and african padauk had 7 and 10 kinds of substance respectively.The result showed that,erucylamide was repeated in 6 kinds of extract,4,4'-Dimethoxybenzoin was repeated in 2kinds of extract in angola padauk and african padauk,isovanillic acid and2-(Methylamino)-5-nitrobenzophenone were repeated in 2 kinds of extract in pterocarpus macrocarpus and african padauk.These repeated substances may have stronger antifungal activity,or there is a synergy between each substance.