Principal component analysis of the biological characteristics of entomopathogenic fungi in nutrient‐limited and cuticle‐based media

Abstract

Media formulated with insect cuticle (0.5% and 1%; Sphequit Sph®), with a reduction in nutrients (¼ Sabouraud dextrose agar + yeast [SDAY]) and commercial media (potato dextrose agar, Sabouraud dextrose agar) were evaluated for the cultivation of Beauveria bassiana, Cordyceps javanica (Isaria javanica [Bally] Samson & Hywel-Jones), and Metarhizium robertsii. By using principal component analysis, it was determined that the ¼ SDAY and Sph formulations have greater advantages than commercial media for the development of fungi. The ¼ SDAY and Sph (0.5% and 1%) improved hydrophobicity, radial growth rate, germination, conidia yield, and virulence in B. bassiana; in M. robertsii, they favored conidia yield, germination, and virulence, and in C. javanica, the ¼ SDAY and Sph 0.5% media enhanced conidia yield, germination, radial growth rate, and virulence. We suggest that these formulations are an alternative to commercial culture media as they are cheaper and appropriate to improve the growth characteristics and virulence of the three strains evaluated. Some applications of culture media are suggested, and the importance of multivariate analysis as an exploratory tool to carry out the choice of culture media in a suitable way for the development of mycoinsecticides is also discussed.

Biomass and Cordycepin Production by the Medicinal Mushroom Cordyceps militaris—A Review of Various Aspects and Recent Trends towards the Exploitation of a Valuable Fungus

“…In line with the aforementioned findings, it was observed that chitosan (a chemical homologue of chitin) could significantly increase carotenoid content in a novel two-stage C. militaris cultivation process [71] (Table 2). In addition, low-nutrient growth media supplemented with insect cuticles increased the pathogenicity of Beauveria bassiana, Cordyceps javanica, and Metarhizium robertsii [33]. These effects are yet to be evaluated for C. militaris, but existing results have already proven a positive impact of insect-based compounds on its growth and productivity.…”

“…Furthermore, in order to optimize C. militaris productivity, many parameters have already been examined through numerous pertinent studies that will be suitably outlined and discussed in the present review. Most of them focused on developing suitable methodologies and interventions to avoid (or minimize) culture degeneration [21][22][23][24][25][26][27][28][29][30][31], on improving ascomata and mycelia production [12,15,[32][33][34][35][36], and/or on enhancing cordycepin output by adopting various approaches and the use of both solid and liquid substrates [12,15,23,32,[37][38][39][40][41][42][43][44][45][46][47]. In addition, the application of genetic engineering breakthrough technologies has resulted in a considerable improvement in C. militaris biomass content in various metabolites, including cordycepin [37,[48][49][50][51].…”

Palm kernel meal improves the production and conidia quality of Cordyceps javanica in conventional solid-state fermentation

“…This assumption is based on the results reported by Angel-Cuapio et al(2015), who used water hyacinth (Eichhornia crassipes) as a texturizer for improving the production of I. fumosorosea aerial conidia.The application of C. javanica in the eld requires a high quantity of viable conidia with proper quality parameters (Arredondo-Bernal and B. Rodríguez-Vélez, 2020; Montesinos Matías et al, 2020), for example, to control D. citri, at least 2×1012 conidia per hectare are required, using a suspension of 1×10 7 conidia • mL − 1 (Sánchez-González et al, 2015; Adame-García et al, 2021). Unfortunately, in the conventional SSF system, a high yield of conidia usually leads to the formation of conidia with low levels of viability and a decrease in virulence(Jaronski, 2014;Montesinos-Matías et al, 2021). In our study, high yields of conidia…”

Biocontrol of Xyleborus affinis (Curculionidae: Scolitinae) Females and Progeny by Beauveria bassiana (Hypocreales: Cordycipitaceae) in a Sawdust Artificial Diet Model

“…Beauveria bassiana strains were cultured on Petri dishes containing SDA, supplemented with 1% SDAY at pH 5.6, and incubated at 27 °C ± 2 °C in darkness [ 25 , 26 ]. After 20 d, conidia were harvested in a 0.05% Tween 80 solution and mixed in a vortex at maximum speed.…”

“…Insects were removed from tubes with or without diet and individually transferred to 1.5 mL Eppendorf tubes containing 150 μL of 0.05% Tween 80. Tubes were then gently shaken for one minute and 10 μL was diluted to 1:1000, after which 30 µL was placed in a selective medium for B. bassiana (SMBb) (39 g L −1 potato dextrose agar; BD Bioxon, Guadalajara, Mexico), supplemented with 2.5 g L −1 bacteriological agar (BD Bioxon Mexico), 80 mg L −1 tetracycline (Sigma-Aldrich, St. Louis, MO, USA), 25 mg L −1 cycloheximide (Sigma-Aldrich), 80 mg L −1 streptomycin (Sigma-Aldrich), 80 mg L −1 penicillin (Sigma-Aldrich), and 1 mg L −1 benomyl (Robust R; Promotora Técnica Industrial, Morelos, Mexico) [ 26 , 27 , 28 ]. The inoculum was distributed using Drigalski rods, and Petri dishes were incubated at 25 °C ± 2 °C for 72 h, after which colony-forming units (CFU) were determined.…”