Characterization of medicinal Ganoderma of GKR7 isolate based on cultural, morphological, and molecular characters

Abstract

Ganoderma has commonly known as traditional medicinal mushroom. The GKR7 fruiting body of Ganoderma has been tested for antimicrobial activity against EPEC-antibiotic resistant strains and has shown great inhibition. However, the pure culture and fruiting body of the GKR7 have not been characterized. This study aimed to characterize the GKR7 based on its cultural features, fruiting body morphology, and molecular analysis. Cultural features and fruiting body morphology were determined by describing macroscopic and microscopic characteristics while molecular analysis was performed using internal transcribed spacer (ITS5/ITS4) region sequencing. The culture showed white then yellow or brown colonies. Hyphal features showed septate, hyaline, dichotomous branches, and having clamp-connection. Oxidation test with gallic/tannic acid formed dark discoloured areas under the colony mat indicating as white rot fungi. The fruiting body which cultivated in Albasia (Albizia falcataria) wood sawdust had hard corky to woody basidioma, dark brown stipe, shell-like pileus, upper surface of pileus white then reddish brown and lower surface yellowish white with irregular circular pores, and hyaline-brown double-walled truncate basidiospores. Phylogenetic analysis indicated that the GKR7 clustered in the same species clade as Ganoderma sichuanense. Based on its characteristics, the GKR7 was identified as G. sichuanense which was first reported in Indonesia.