Paecilomyces cicadae: a systematic overview of the biological activities and potential mechanisms of its active metabolites

The microbe Paecilomyces cicadae (Miquel) Samson (P. cicadae) is an asexual strain of Cordyceps cicadae (C. cicadae) used in traditional Chinese medicine. Due to the abundance of secondary metabolites found in cultured metabolites, including polysaccharides, hyaluronic acid, ergosterol peroxide, and active nucleosides, P. cicadae and/or C. cicadae exhibit several therapeutic activities, including immunoregulatory, antioxidant, and anti-diabetic effects. Given the great attention for health care and the desirable medical value of C. cicadae and/or P. cicadae, they are becoming potential alternatives of Cordyceps sinensis (C. sinensis). Although there are many studies on P. cicadae/C. cicadae, most of them are experimental research articles. There are limited reviews to summarize the latest researches on P. cicadae/C. cicadae. This review mainly focuses on the metabolites, physiological activities and mechanisms of action of P. cicadae and/or C. cicadae. This review can serve as a theoretical basis for the more efficient use of this medicinal fungus.