Production of hybrid strains among Pleutorus and Lentinula and evaluation of their mycelial growth kinetics on malt extract agar and wheat grain using the Gompertz and Hill models

Abstract

Three inter-generic hybrid strains were obtained by pairing compatible neohaplonts recovered by dedikaryotization of four parental strains, i.e. Pleurotus ostreatus (CC060), Pleurotus djamor (CC051) and Lentinula edodes (CC003 and CC004). Fifteen neohaplonts were recovered employing homogenization time periods for Pleurotus spp. since 60 to 90 s, and for Lentinula edodes strains time periods ranged from 5 to 20 s, and incubation at 28 °C in a peptone-glucose solution (PGS). The mycelial growth of the parental and hybrid strains was determined on malt extract agar (MEA) and wheat grain by calculating the parameters A, B and C of nonlinear regression models. For the parameter A, the mycelial growth on MEA showed values ranged from 1.08 to 1.28, and for the parameter B since 5.65 to 20.85. On the other hand, the A values by mycelium growth on wheat grain ranged from 1.57 to 16.13, for B since 28.36 to 86.53 and for C were in an interval from 11.89 to 44.24. Parental and hybrid strains presented instantaneous velocity values on MEA since 2.88 to 7.26 cm2•day-1, whereas on wheat grain were in an interval from 5.45 to 10.05 cm3•day-1. Furthemore, the µmax values on MEA and wheat grain were calculated by using the Gompertz model and the λ values on both medium were estimated by using the Hill model, the µmax values on MEA ranged from 0.26 to 1.69 day-1 and λ values in an interval from 0.41 to 2.74, whereas the µmax values on wheat grain ranged from 0.05 to 0.43 day-1 and λ since 1.82 to 28 h. Moreover, the estimated equations based on nonlinear models were used to calculate the µmax values on MEA and wheat grain of the strains and the λ values were obtained by using the µmax values of the proposed equations on the Hill model, the µmax values on MEA ranged from 0.44 to 1.27 day-1 and the λ values between 0.57 to 1.72 h, while the µmax values on wheat grain ranged from 0.04 to 0.64 day-1 and λ values in an interval from 1.26 to 20.11 h. The results evidenced that the hybrid strains of PleurotusxLentinula presented highest rate of growth in comparison with the parental, encouraging the production of hybrid strain and their use in the industrial field.

A novel coconut-malt extract medium increases growth rate of morels in pure culture

“…The values of µ max obtained for morels are one order of magnitude superior (10.37 ± 0.58 to 40 ± 0.39 mm d −1 ; Fig. 5 b) to those reported by Valenzuela-Cobos et al ( 2017 ). Notice that morel mycelium is considered a fast growing mycelium.…”

“…During this period, diverse physiological processes took place with the aim of providing an adaptation to the surrounding growing environment. Valenzuela-Cobos et al ( 2017 ) fitted growth of P. ostreatus, P. djamo r and Lentinula edodes by using the Gompertz model and a nonlinear model. The values of λ ranged from 0.41 to 2.74 days.…”

“…Valenzuela-Cobos et al ( 2017 ) reported µ max values for P. ostreatus, P. djamo r and L. edodes in a range from 0.44 to 1.27 days −1 for the modified Gompertz model and 0.26 to 1.69 day −1 by using the nonlinear model . The values of µ max obtained for morels are one order of magnitude superior (10.37 ± 0.58 to 40 ± 0.39 mm d −1 ; Fig.…”

Biodegradation of cocoa shell by phytopatogenic fungi for Pleurotus ostreatus production

“…Moisture, ash, crude fiber and crude fat were determined according to the Association of Official Analytical Chemists methods (AOAC, 1997). Total nitrogen were evaluated with the microkjeldahl method, crude protein was calculated from total nitrogen content by employing the converting factor 4.38, total carbohydrates were calculated by the formula: 100 -(% protein + % fat + % ash contents), and energy value was estimated according to the equation: energy = 4 x (% protein + % carbohydrate) + 9 x (% fat) (Manzi et al, 2004;Valencia del Toro et al, 2018). The energy value of mushrooms was estimated based on the content of crude protein (Nx4.38), fat and carbohydrate using specific modified factors 3.75, 8.37 and 4.2 kcal g −1 of each component, respectively (Lau, 1982).…”

“…The fruiting bodies of the strain of Pleurotus ostreatus cultivated in a mixture D presented the highest value of fat content being of 1.75%, whereas the mushrooms bodies of the strain of Pleurotus ostreatus produced in a mixture D1 showed the lowest fat content being of 1.10%. The moisture and fat content of the fruiting bodies is influenced by the composition of the substrates used in the production of the mushroom (Valencia del Toro et al, 2018;Valenzuela-Cobos et al, 2020b) .…”