纤维板霉变微生物的分离鉴定及生长抑制方法

Isolation,identification and growth inhibition of microorganisms mildew of fiberboard

为了明确纤维板霉变微生物的种类,寻找抑制其生长的方法,对引起纤维板霉变的微生物进行了分离纯化,采用传统真菌形态学观察和核糖体DNA-内转录间隔区(rDNA-ITS)序列分析相结合的方法对其加以鉴定,并探究了碘丙炔醇丁基氨甲酸酯(IPBC)和紫外线辐照处理对霉菌生长的影响。结果表明:分离得到的10株霉菌经形态学分析初步鉴定为曲霉属(Aspergillus sp.)、青霉属(Penicillium sp.)和短梗霉属(Aureobasidium sp.),其中曲霉属真菌为优势种群;通过rDNA-ITS序列分析及构建系统进化树,将该10株霉菌确定为7个种,分别为帚状曲霉(A.penicillioides)、简青霉(P.simplicissimum)、假灰绿曲霉(A.pseudoglaucus)、谢瓦氏曲霉(A.chevalieri)、阿姆斯特丹曲霉(A.amstelodami)、产黑色素短梗霉(A.melanogenum)和爪甲团囊菌目(Onygenales)的Sigleria carmichaelii。抑菌试验结果表明,质量分数为0.10%的IPBC试剂处理或紫外线辐照(功率38 W,波长253.7 nm)处理15 min,即可明显抑制纤维板霉变微生物的生长。研究结果不但丰富了纤维板霉变微生物的种类范畴,而且为纤维板产品霉变防控和防霉剂的研发等提供了参考依据。

There are many microorganisms in nature that can degrade lignocellulose.Coupled with the impact of the existing fiberboard manufacturing process and the storage environment,the fiberboard is more prone to be mildewed.Targeted strain selection is the key to the development of fiberboard mold inhibitors.However,at present,there are few studies on the identification of microorganism-causing mildew of fiberboard.Therefore,in order to clarify the types of microorganism mildew of fiberboard and explore the methods for inhibiting its growth.The authors used the dilution plate method and the three-zone line method to isolate and purify the microorganism mildew of fiberboard.A combination method of traditional fungal morphological observations and rDNA-internal transcribed spacer(rDNA-ITS)sequence analyses was used to identify them.Then the effects of the 3-lodo-2-propynyl butylcarbamate(IPBC)and ultraviolet radiation treatment on the mold growth were studied.The results showed that 10 strains were isolated from the samples.According to the traditional fungal morphological results,these strains belonged to Aspergillus sp.,Penicillium sp.and Aureobasidium sp.And Aspergillus sp.is the dominant species.Through the analysis of rDNA-ITS sequence and construction of phylogenetic tree,the 10 strains were identified as 7 species,such as A.penicillioides,P.simplicissimum,A.pseudoglaucus,A.chevalieri,A.amstelodami,A.melanogenum,and Sigleria carmichaelii of Onygenales.The Sigleria carmichaelii was initially discovered by Hirooka scholars in the household dust in 2015.At present,there is no specific taxonomy and Chinese name for it in academic circles.A.melanogene and Sigleria carmichaelii are newly discovered microorganisms mildew of fiberboard.The basic physiological characteristics of molds collected at the American Type Culture Collection(ATCC)are presented that the above seven different molds are all dry-tolerant dry molds.Their suitable growth temperature is about 25℃and can grow when the water activity of the materials is above 0.65.The antibacterial test results showed that the treatment with 0.10%(w/w)IPBC reagent or ultraviolet irradiation(a power of 38 W and a wavelength of 253.7 nm)for 15 min can significantly inhibit the growth of moldy microorganisms on fiberboard.Therefore,within the safe dose range,the rational use of IPBC or ultraviolet radiation to process the operating surface,raw materials or products can achieve the purpose of preventing mildew of fiberboard.The research results not only enriched the types of microorganisms mildew of fiberboard,but also provided a certain reference for the anti-mildew of fiberboard products and the research of antifungal agents for fiberboard products.