Nine aromatic compounds (caffeic acid, syringaldehyde, vanillic acid, guaiacol, vanillin, sinapic acid, syringol, syringic acid and ferulic acid) and four metallic compounds (CuSO4, AgNO3, MnSO4, and CaCl2) were tested for their ability to increase laccase (Lac) activity in the ligninolytic basidiomycete Phlebia brevispora BAFC 633. The addition of syringaldehyde, syringol, guaiacol, sinapic acid, vanillin, ferulic acid and CuSO4 showed a positive effect on fungal growth; however, it decreased dramatically with the addition of AgNO3 and did not undergo changes in the presence of CaCl2 or MnSO4. Lac activity increased with the addition of all the compounds tested, depending on the concentration and the day of culture. P. brevispora BAFC 633 produced two isoenzymes, a constitutively expressed of 60 kDa and another of 75 kDa expressed upon induction by sinapic acid, MnSO4 or CuSO4. Lac secretion capacity of P. brevispora BAFC 633 can be increased 27 times higher than the control with the highest levels detected in the presence of 0.3 mM CuSO4 at day 14. The action is affected at pre-transcriptional level regulating at the onset of the process, however it does not rule out the effect at the post-transcriptional and post-translational levels, for which is necessary to deepen in the knowledge of all possible regulation points of gene expression.
The agricultural industries generate lignocellulosic wastes that can be modified by fungi to generate high value-added products. The aim of this work was to analyze the efficiency of the bioconversion of sugarcane bagasse and cassava bagasse using two cheap home-made enzymatic cocktails from Aspergillus niger LBM 134 (produced also from agroindustrial wastes) and compare the hydrolysis yield with that obtained from the bioconversion using commercial enzymes. Sugarcane bagasse and cassava bagasse were pretreated with a soft alkaline solution before the hydrolysis carried out with home-made enzymatic cocktails of A. niger LBM 134 and with commercial enzymes to compare their performances. Mono and polysaccharides were analyzed before and after the bioconversion of both bagasses as well as their microscopic structure. The maximal yield was the 80% of total glucans saccharified from cassava bagasse. The bioconversion of both bagasses were better when we used the home-made enzymatic cocktails than commercial enzymes. We obtained high added-value products from agroindustrial wastes, home-made enzymatic cocktails and hydrolysates rich in fermentable sugars. The importance of this work lays in the higher performance of the cheap home-made enzymatic cocktails over the hydrolytic performance of commercial enzymes due to the cost of producing the home-made enzymatic cocktails were more than 500 times lower than commercial enzymes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.