Identification and Characterization of Citric Acid-Producing Fungi from Soil and Melon (Cucumeropsis mannii) Rind Samples Collected from Melon Farm in Lafia, Nasarawa State, Nigeria

Fatima Adis Adamude; Abdulrahman Muhammad; Abdulrazak Mohammed Adewumi; Hassan Badeggi Muhammad; Monday Nwankwo; Femi Ayo Gbadeyan; Shiri Umbugadu

doi:10.62050/ljsir2026.v4n2.848

المؤلفون

Fatima Adis Adamude
Department of Biochemistry, Federal University of Lafia, Nasarawa State, Nigeria
Abdulrahman Muhammad
alameenmuhammad30@gmail.com

Department of Biochemistry, Federal University of Lafia, Nasarawa State, Nigeria
Abdulrazak Mohammed Adewumi
Department of Biochemistry, Federal University of Lafia, Nasarawa State, Nigeria
Hassan Badeggi Muhammad
Department of Biochemistry, Federal University of Lafia, Nasarawa State, Nigeria
Monday Nwankwo
Department of Anatomy, Federal University of Lafia, Nasarawa State, Nigeria
Femi Ayo Gbadeyan
Department of Microbiology, Federal University of Lafia, Nasarawa State, Nigeria
Shiri Umbugadu
Department of Microbiology, Federal University of Lafia, Nasarawa State, Nigeria

الكلمات المفتاحية:

Citric acid , fungi isolate , Aspergillus niger , fermentation process , microbial isolation and screening

الملخص

The essential and important organic acid used industrially worldwide for microbial fermentation especially filamentous fungi is citric acid. In this investigation, soil and melon rind (Cucumeropsis mannii) samples from melon farms in Lafia, Nasarawa State, Nigeria. These was used to isolate, screen, identify, and characterize citric acid-producing fungi. Standard microbiological culture protocols were used for serial dilution followed by plating on Potato Dextrose Agar (PDA). The samples were also cultivated on Czapek-Dox Agar (CZA) enriched with bromocresol green to specifically achieve acidogenic strains isolates. This specialized medium allowed for the identification of potent isolates with observable translucent halo zones around the colonies. Green colonies were the most common of the 212 fungal colonies that were obtained. Morphological and microscopic characterization revealed the presence of several fungal genera, including Aspergillus niger, Aspergillus flavus, Aspergillus tamarii, Penicillium spp., Fusarium spp., and Rhizopus stolonifer. Out of the characterise4d and identified fungus Aspergillus niger shows highest potential for citric acid production. The results highlighted the possibility to use melon rind as an inexpensive substrate for industrial fermentation operations and revealed the abundance of native fungi in soil and agricultural leftovers capable of generating citric acid. This research shows how local microbial sources can be effectively used in industries and biotechnological projects.

Dimensions

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