UNIVERSITÉ PAUL CÉZANNE, AIX MARSEILLE III - IMEP

Ergosterol content (mg.g -1 )
Résultats et discussion. Chapitre 2: Optimisation de la production du spawn
Figure 5. Correlation between ergosterol content and CO2 production by L. edodes Le119 in
WS ( ) and BS ( ) incubated at 25°C during 20 days.
4. Discussion
CO2 production (mL .h -1 .g -1 dw)
Estimation of fungal biomass in solid state fermentation was subject of several studies
(Ooijkaas et al., 1998; Scotti et al., 2001; Niemenmaa et al., 2008). Therefore, respiration
measurement (O2 consumption or/and CO2 production) and biochemical analysis of cell
components were evaluated to find a good indicator for biomass estimation. Thus, the
combination of different indicators was carried out in order to offer a significant improvement
of correlation between real biomass and which was estimated (Matcham et al., 1985; Ooijkaas
et al., 1998). Whereas, higher the number of indicators, the more difficult to interpret the
results and the conversion of growth become totally impracticable.
In our study, ergosterol was tested for estimation of L. edodes biomass cultivated in
solid state fermentation to produce spawn of L. edodes which is the main factor of the
attainment for high quality crop of mushroom (Mamiro and Royse 2008; Kuforiji and Fasidi
2009; Royse and Chalupa 2009). Ergosterol content showed close correlation to mycelial
growth (r= 0.987). Similar result was obtained for Agaricus bisporus (Matcham et al., 1985)
which was cultivated on different media in solid and liquid state culture, while it was in
disagreement with Coniothyrium minitans produced on PDA (Ooijkaas et al., 1998).The
explanation could be that the spore production of C.minitans affects the ergosterol content
which in return was depending to the nature of substrate. Thus the determination of ergosterol
could present a good result for estimation of basidiomycete mycelium.
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