초록
<P><B>Abstract</B></P> <P>Microbial hydrolytic enzymes are relevant biotechnological products that can be applied in various industries. In this study, we have tested the activity of hydrolytic enzymes of a newly isolated <I>Hymenobacter</I> sp. CKS3 strain and showed, for the first time, that members of <I>Hymenobacter</I> genus have still unexplored hydrolytic potential. Crude hydrolytic enzymes, produced by the strain CKS3 on a waste medium, were incorporated into a process of bioethanol production using waste bread. The conditions for bread hydrolysis were optimized using statistical design. Waste bread hydrolysate obtained under optimal conditions (100.73 h of hydrolysis, waste bread concentration 20.36% and agitation speed 200 rpm) contained 19.89 g/l of reducing sugars. A high performance liquid chromatography of hydrolyzed waste bread samples showed that the main components of the hydrolysate were dextrins, maltotriose, maltose and glucose. When using this substrate and waste baker’s yeast for ethanol production under non-optimized conditions 1.73% of ethanol was produced. The results of this study showed that a newly isolated <I>Hymenobacter</I> sp. CKS3 can be utilized for enzymatic hydrolysis and bioethanol production in a process relying on waste materials. Furthermore, it was demonstrated that members of <I>Hymenobacter</I> genus have a significant and currently unexplored potential for bio-based industrial applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> First report of <I>Hymenobacter</I> enzymatic potential for waste bread hydrolysis. </LI> <LI> Production of enzymes by novel red pigment bacterial strain <I>Hymenobacter</I> sp. CKS3. </LI> <LI> An optimal design was used for optimize enzymatic hydrolysis of waste bread. </LI> <LI> 19.89 g/l of reducing sugars was released from waste bread by CKS3 crude amylase. </LI> <LI> The optimized waste bread hydrolysate was used for ethanol production. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>