Agricultural University of Athens, Department of Agricultural Biotechnology, Laboratory of General and Agricultural Microbiology, Iera Odos 75, 11855 Athens, Greece.
Fungal Biol. 2012 Jun;116(6):715-28. doi: 10.1016/j.funbio.2012.04.006. Epub 2012 Apr 19.
Fourier transform infrared (FT-IR) spectroscopy has been successfully applied for the identification of bacteria and yeasts, but only to a limited extent for discriminating specific groups of filamentous fungi. In the frame of this study, 73 strains - from different associated hosts/substrates and geographic regions - representing 16 taxa of the edible mushroom genus Pleurotus (Basidiomycota, Agaricales) were examined through the use of diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. A binary matrix, elaborated on the basis of presence/absence of specific absorbance peaks combined with cluster analysis, demonstrated that the spectral region 1800-600 cm(-1) permitted clear delimitation of individual strains into Pleurotus species. In addition, closely related species (e.g., Pleurotus ostreatus and Pleurotus pulmonarius) or taxa of the subgenus Coremiopleurotus demonstrated high similarity in their absorbance patterns, whereas genetically distinct entities such as Pleurotus dryinus, Pleurotus djamor, and Pleurotus eryngii provided spectra with noteworthy differences. When specific regions (1800-1700, 1360-1285, 1125-1068, and 950-650 cm(-1)) were evaluated in respect to the absorbance values demonstrated by individual strains, it was evidenced that this methodology could be eventually exploited for the identification of unknown Pleurotus specimens with a stepwise process and with the aid of a dichotomous key developed for this purpose. Moreover, it was shown that the nature of original fungal material examined (mycelium, basidiomata, and basidiospores) had an effect on the outcome of such analyses, and so did the use of different mycelium growth substrates. In conclusion, application of FT-IR spectroscopy provided a fast, reliable, and cost-efficient solution for the classification of pure cultures from closely related mushroom species.
傅里叶变换红外（FT-IR）光谱学已成功应用于细菌和酵母的鉴定，但仅在有限程度上用于区分特定的丝状真菌群体。在本研究中，使用漫反射红外傅里叶变换（DRIFT）光谱法检查了来自不同相关宿主/基质和地理区域的 73 株代表食用蘑菇属 Pleurotus（担子菌门，伞菌目）的 16 个分类群的菌株。基于存在/不存在特定吸收峰的二元矩阵，结合聚类分析，证明光谱区域 1800-600 cm(-1) 允许将单个菌株清晰地区分为 Pleurotus 种。此外，密切相关的物种（例如，糙皮侧耳和肺形侧耳）或 Coremiopleurotus 亚属的分类群在其吸收模式中表现出高度相似性，而遗传上不同的实体，如 Pleurotus dryinus、Pleurotus djamor 和 Pleurotus eryngii，则提供了具有显著差异的光谱。当评估特定区域（1800-1700、1360-1285、1125-1068 和 950-650 cm(-1)) 时，就各个菌株表现出的吸收值而言，结果表明，该方法最终可以用于通过逐步过程并借助为此目的开发的二叉关键识别未知的 Pleurotus 标本。此外，还表明检查的原始真菌材料（菌丝体、担子果和担孢子）的性质以及使用不同的菌丝体生长基质对这些分析的结果有影响。总之，FT-IR 光谱学的应用为密切相关的蘑菇物种的纯培养物分类提供了一种快速、可靠且具有成本效益的解决方案。
