Mora-Pérez Christian Jesús, Favela-Torres Ernesto, Montesinos-Matias Roberto, Berlanga-Padilla Angélica María, Méndez-González Fernando
Departamento de Biotecnología, Universidad Autónoma Metropolitana, Iztapalapa, Mexico City, 09340, Mexico.
Centro Nacional de Referencia Fitosanitaria, Departamento de Control Biológico, SENASICA, Tecomán, Colima, 28110, Mexico.
Folia Microbiol (Praha). 2025 Sep 2. doi: 10.1007/s12223-025-01320-1.
Accurate quantification of spore concentration is essential in producing, analyzing, and applying diverse biotechnological products. Typically, spore concentration is estimated using a Neubauer hemocytometer, which is labor-intensive, time-consuming, and often imprecise. Methods based on spore optical properties can be explored as an alternative to using the Neubauer hemocytometer, improving the practicality and precision of analysis. This study aimed to establish the analysis conditions for quantifying the spore concentration using spectrophotometry and colorimetry (using Lab color space). For this study, spores from entomopathogenic fungi Beauveria bassiana, Hirsutella thompsonii, Cordyceps fumosorosea, Cordyceps javanica, Akanthomyces dipterigenus, Metarhizium acridum, Metarhizium anisopliae, and Metarhizium robertsii were produced and analyzed. The results indicate that both spectrophotometry and colorimetry analysis accurately estimate spore concentration. The quantification ranges achieved with both methods directly depend on the spore volume. Spores with a 15 µm or less volume exhibit a wider quantification range than those with larger volumes. Moreover, the Lab* color space analysis allows quantifying spores in a concentration range from 4.5 × 10 to 3 × 10 spores/mL, which is wider than the range obtainable through spectrophotometry. This extended concentration range provided by colorimetry offers a practical advantage for producing and applying entomopathogenic fungi spores.
准确量化孢子浓度对于生产、分析和应用各种生物技术产品至关重要。通常，使用血细胞计数板估计孢子浓度，这种方法劳动强度大、耗时且往往不准确。基于孢子光学特性的方法可作为使用血细胞计数板的替代方法进行探索，从而提高分析的实用性和准确性。本研究旨在建立使用分光光度法和比色法（使用Lab颜色空间）量化孢子浓度的分析条件。在本研究中，制备并分析了来自球孢白僵菌、汤普森被毛孢、玫烟色虫草、爪哇虫草、双翅虫霉、绿僵菌、金龟子绿僵菌和罗伯茨绿僵菌等昆虫病原真菌的孢子。结果表明，分光光度法和比色法分析均能准确估计孢子浓度。两种方法实现的量化范围直接取决于孢子体积。体积为15 µm或更小的孢子比体积较大的孢子具有更宽的量化范围。此外，Lab*颜色空间分析能够在4.5×10至3×10个孢子/mL的浓度范围内量化孢子，这一比分光光度法可获得的范围更宽。比色法提供的这一扩展浓度范围为昆虫病原真菌孢子的生产和应用提供了实际优势。
