DEVELOPMENT OF A NEW METHOD FOR RAPID IDENTIFICATION OF ASPERGILLUS FLAVUS STRAINS USING RAMAN SPECTROSCOPY
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Abstract
Background: Fungi have been identified as direct and hazardous agents that can damage long-term preserved remains intended for public display. Upon contaminating the tissues of preserved bodies from external environments, microfungi proliferate through invasive mechanisms and enzymatic secretion, leading to the structural degradation of skin and hair tissues. Therefore, the development of novel, rapid, and reliable fungal identification methods is essential and highly significant.
Objective: To apply Raman spectroscopy for the rapid identification of A. flavus strains.
Methods: The A. flavus strain (QG17-007) was revived and morphologically identified using optical microscopy and Scanning Electron Microscopy (SEM). Raman spectroscopy was subsequently performed under optimized conditions (laser source, substrate, and conidia concentration) to acquire characteristic spectra. These spectra were compared with standard data libraries for species identification.
Results: Raman spectra obtained from A. flavus exhibited characteristic peaks at 414, 421, 1001, 1193, 1350, 1445, 1463, 1648, 1673, and 1745 cm⁻¹. These peaks correspond to specific bonds within the primary biological structures of the conidia, including β(1,3)-D-glucan/chitin of the cell wall, phenylalanine (protein), amide I, amide III, and lipids characteristic of A. flavus.
Conclusion: This study demonstrates the potential of Raman spectroscopy as a rapid diagnostic method for identifying fungal strains and their components currently preserved at Institute 69.
Keywords
Raman spectroscopy, Aspergillus flavus, conidia
Article Details
References
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