Plasma Bioscience Research Center, Kwangwoon University, Seoul, 01897, Korea.
Department of Plasma Bioscience and Display, Kwangwoon University, Seoul, 01897, Korea.
Sci Rep. 2019 Aug 1;9(1):11184. doi: 10.1038/s41598-019-47705-4.
Poor and unstable culture growth following isolation presents a technical barrier to the efficient application of beneficial microorganisms in the food industry. Non-thermal atmospheric pressure plasma is an effective tool that could overcome this barrier. The objective of this study was to investigate the potential of plasma to enhance spore germination, the initial step in fungal colonization, using Aspergillus oryzae, a beneficial filamentous fungus used in the fermentation industry. Treating fungal spores in background solutions of phosphate buffered saline (PBS) and potato dextrose broth (PDB) with micro dielectric barrier discharge plasma using nitrogen gas for 2 and 5 min, respectively, significantly increased the germination percentage. Spore swelling, the first step in germination, was accelerated following plasma treatment, indicating that plasma may be involved in loosening the spore surface. Plasma treatment depolarized spore membranes, elevated intracellular Ca levels, and activated mpkA, a MAP kinase, and the transcription of several germination-associated genes. Our results suggest that plasma enhances fungal spore germination by stimulating spore swelling, depolarizing the cell membrane, and activating calcium and MAPK signaling.
在隔离后，不良和不稳定的培养会对食品工业中有益微生物的有效应用造成技术障碍。非热常压等离子体是一种有效的工具，可以克服这一障碍。本研究的目的是探讨等离子体增强孢子萌发的潜力，孢子萌发是真菌定殖的初始步骤，使用米曲霉（Aspergillus oryzae），一种用于发酵工业的有益丝状真菌。用氮气分别处理磷酸盐缓冲盐水（PBS）和土豆葡萄糖肉汤（PDB）背景溶液中的真菌孢子 2 和 5 分钟，使用微介质阻挡放电等离子体，可显著提高孢子的萌发率。等离子体处理后，孢子的膨胀（萌发的第一步）加速，表明等离子体可能参与了孢子表面的松解。等离子体处理使孢子膜去极化，提高了细胞内 Ca 水平，并激活了 mpkA（一种丝裂原激活蛋白激酶）和几个与萌发相关的基因的转录。我们的结果表明，等离子体通过刺激孢子膨胀、去极化细胞膜以及激活钙和 MAPK 信号来增强真菌孢子的萌发。
