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The capability of 5 strains of 2 species of genus Cerrena (Aphyllophoromycetideae) to express hemagglutinating activity (HA) was evaluated in submerged fermentation of 7 lignocellulosic materials of different chemical compositions. Among the lignocellulosic substrates tested, walnut pericarp, followed by mandarin and kiwi peels provided the highest specific HA of C. unicolor IBB 300; walnut leaves and pericarp appeared to be the best substrates for the accumulation of lectin by C. unicolor IBB 301, whereas the fermentation of kiwi peels ensured the highest HA of C. unicolor IBB 302. The highest HA was detected in C. maxima IBB 402 cultivation in submerged fermentation of walnut leaves (64103 U/mg), mandarin (33333 U/mg) and kiwi peels (28571 U/mg). Moreover, the fermentation of walnut pericarp and leaves provided the secretion of high lectin levels in culture liquid (9143 U/mg). The carbohydrate specificity of tested preparations significantly depended on both fungus strain and lignocellulosic growth substrate. By substitution of lignocellulosic material, it is possible to regulate lectin production and to obtain a preparation with different specificity toward carbohydrates.

The capability of Cerrena unicolor to produce fruiting bodies and lectins was studied in solid-state fermentation of a sorghum and wheat straw mixture. The first primordia appeared on day 48 and reached 6-10 mm; however, no formation of fruiting bodies occurred and these rudiments were harvested on day 55. The protein content in the rudiment extracts was significantly higher, whereas the specific hemagglutinating activity (HA) was sixfold lower as compared with those in extracts from mycelial biomass. Moreover, the specific HA of the 80-day mycelium increased to 16,667 U/mg, exceeding by sixfold that of 55-day-old mycelium. Four protein fractions (160, 105, 67, and 8 kDa) were detected by gel-chromatography of mycelial biomass crude extract; the highest specific HA was revealed in fraction III (26336 U HA/mg). Among sugars tested, galactose was the most potent inhibitor of HA of all protein fractions, with minimal inhibition concentrations of 0.095-0.780 mM. The galactose-specific lectins isolated from the fractions II and III by affinity chromatography ranged from 15 to 116 kDa and differed with kinetic parameters.