Richness of endophytic fungi isolated from Opuntia ficus-indica Mill. (Cactaceae) and preliminary screening for enzyme production

Abstract

Opuntia ficus-indica Mill. (forage cactus) is farmed with relative success in the semi-arid region of the Brazilian northeast for commercial purposes, particularly as forage and food. Endophytic microorganisms are those that can be isolated inside plant tissues and can be a new source to production of enzymes with different potentialities. The objective of this study was to describe the richness of endophytic fungi from O. ficus-indica and to detect the capacity of these species to produce extracellular hydrolytic enzymes. Forty-four endophytic fungi species were isolated. Among them, the most commonly found were Cladosporium cladosporioides (20.43%) and C. sphaerospermum (15.99%). Acremonium terricola, Monodictys castaneae, Penicillium glandicola, Phoma tropica and Tetraploa aristata are being reported for the first time as endophytic fungi for Brazil. The majority of isolated fungi exhibited enzymatic potential. Aspergillus japonicus and P. glandicola presented pectinolytic activity. Xylaria sp. was the most important among the other 14 species with positive cellulase activity. All 24 isolates analysed were xylanase-positive. Protease was best produced by isolate PF103. The results indicate that there is a significant richness of endophytic fungi in O. ficus-indica, and that these isolates indicate promising potential for deployment in biotechnological processes involving production of pectinases, cellulases, xylanases and proteases.

Diversity, distribution and biotechnological potential of endophytic fungi

“…Endophytic fungi are important producers of enzymes, and have high capability for production of extracellular enzymes such as cellulases, chitinases, laccase, pectinases, xylanases, proteases, amylases, β-galactosidase and other catabolic enzymes (Jordaan et al 2006;Bischoff et al 2009;Borges et al 2009;Rajulu et al 2011;Bezerra et al 2012). Chitinase is applied to the biological control of phytopathogens as it degrades the chitin of the pathogen cell wall.…”

“…Recent studies have revealed a large richness of endophytic fungal species and diverse metabolites with different functions (Zimmerman and Vitousek 2012;Xiao et al 2014;Zhang et al 2014a, b). In some cases, they can enhance plant growth (Waller et al 2005), act as biological control agents (Zhang et al 2014c), and produce enzymes (Bezerra et al 2012). The endophytic fungi are relatively unexplored and could be potential sources of novel natural products for exploitation in medicine, agriculture, and industry (Strobel et al 2004).…”

Fungal Endophytes in Aboveground Tissues of Desert Plants: Infrequent in Culture, but Highly Diverse and Distinctive Symbionts

“…Such work has greatly enhanced our understanding of the geographic-, host-, and tissue-affiliations of fungi that are symbiotic with ecologically important plants in semi-arid grasslands and deserts, especially grasses and sedges [34, 47], gypsophilous plants [69], and selected dicotyledonous plants such as Atriplex spp. [16, 54] and some Cactaceae [17, 83; see also 51]. However, gaps remain with regard to understanding the diversity and composition of fungal communities in above-ground tissues of many woody plants in arid ecosystems, including those non-succulent species that form the dominant cover in some of the world's most biotically rich deserts.…”

Selection and molecular identification of fungal isolates that produce xylanolytic enzymes

“…Additionally, it causes severe diseases in a variety of hosts, including plants and vertebrates (Faisal et al, 2007;Tullio et al, 2010). However, few studies have examined the xylanolytic activity on Phoma species (Bradner et al, 1999;Yang et al, 2005;Bezerra et al, 2012).…”