Abstract:
The binding of conidia to surfaces is a prerequisite for biofouling by fungal species. In this study, Aspergillus niger subtypes 1957 and 1988 were used which produced differently shaped conidia (round or spikey respectively). Test surfaces were characterised for their surface topography, wettability, and hardness. Conidial assays included perpendicular and lateral force measurements, as well as attachment, adhesion and retention assays. Anionic surfaces were less rough (Ra 2.4 nm), less wettable (54°) and harder (0.72 GPa) than cationic surfaces (Ra 5.4 nm, 36° and 0.5 GPa, respectively). Perpendicular and lateral force assays demonstrated that both types of conidia adhered with more force to the anionic surfaces and were influenced by surface wettability. Following the binding assays, fewer A. niger 1957 and A. niger 1988 conidia bound to the anionic surface. However, surface wettability affected the density and dispersion of the conidia on the coatings, whilst clustering was affected by their spore shapes. This work demonstrated that anionic surfaces were more repulsive to A. niger 1998 spores than cationic surfaces were, but once attached, the conidia bound more firmly to the anionic surfaces. This work informs on the importance of understanding how conidia become tightly bound to surfaces, which can be used to prevent biofouling.
摘要:
分生孢子与表面的结合是真菌生物污染的先决条件。在这项研究中,使用黑曲霉亚型1957年和1988年,它们产生不同形状的分生孢子(分别为圆形或螺旋状)。测试表面的表面形貌特征,润湿性,和硬度。分生孢子测定包括垂直和横向力测量,除了依恋,粘附和保留测定。阴离子表面较不粗糙(Ra2.4nm),比阳离子表面(Ra5.4nm,36°和0.5GPa,分别)。垂直和横向力测定表明,两种类型的分生孢子都以更大的力粘附到阴离子表面,并受到表面润湿性的影响。在结合测定之后,与阴离子表面结合的A.niger1957和A.niger1988分生孢子较少。然而,表面润湿性影响分生孢子在涂层上的密度和分散,而聚类受到孢子形状的影响。这项工作表明,阴离子表面比阳离子表面更排斥A.niger1998孢子,但是一旦连接,分生孢子更牢固地结合到阴离子表面。这项工作说明了理解分生孢子如何与表面紧密结合的重要性,可用于防止生物污染。