Developement of combined decontamination methods utilizing superior cell-kiling property of quantum beams and application to efficient treatment of injured microorganisms

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K12496
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 80040:Quantum beam science-related
• Research Institution: Osaka Metropolitan University (2022); Osaka Prefecture University (2020-2021)
• Principal Investigator: Furuta Masakazu 大阪公立大学, 大学院工学研究科, 教授 (40181458)
• Co-Investigator(Kenkyū-buntansha): 朝田 良子 大阪公立大学, 大学院工学研究科, 助教 (60546349) ; 土戸 哲明 大阪公立大学, 研究推進機構, 客員教授 (50029295) ; 坂元 仁 大阪公立大学, 研究推進機構, 客員研究員 (40570560) ; 高松 宏治 摂南大学, 薬学部, 教授 (70272151) ; 桑名 利津子 摂南大学, 薬学部, 講師 (50330361)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 殺菌 / 放射線 / UV / 加熱 / 精油 / 枯草菌 / 芽胞 / 発芽

Outline of Final Research Achievements

We evaluated the effects of gamma irradiation, heat treatment, UV irradiation, and essential oil components (Carvacrol and Thymol) on the germination and vegetative growth process of Bacillus subtilis spores. The essential oil components inhibited both germination and nutrient proliferation processes, with thymol exhibiting a stronger effect at lower concentrations compared to carvacrol. In the case of heat treatment, germination activation occurred, and the temperature dependence differed between the L-alanine germination system and the AGFK germination system. Damage to the germination system caused by gamma irradiation was minimal. On the other hand, Peracetic acid effects to affect the germination process of the spore was affected by the presence of the spore coat and SH groups within the spore coat. Killing effect of UV irradiation was attributed to not only DNA damage in spores but also denaturation of proteins involved in germination.

Free Research Field

微生物制御工学

Academic Significance and Societal Importance of the Research Achievements

食品の成分や食味の変化を最小限に抑え、より良い品質を保つための殺菌法はハードルテクノロジー理論に基づいた複合殺菌の開発が不可欠であり、その中で量子ビーム殺菌の利点が最大限に生かせる最適条件の確立が求められる。本研究の成果は、食品産業の製造現場の微生物制御の標的として最も重要視されている細菌芽胞を対象として得られたものであり、これらは従来の殺滅菌研究において検討されてこなかった申請者独自の実験系を含んで降り、HACCP管理に適した効果の高い殺滅菌システムの構築に繋がる発展が期待される。