Choińska-Pulit Anna, Sobolczyk-Bednarek Justyna, Łaba Wojciech
"Poltegor-Institute", Opencast Mining Institute, Parkowa 25, 51-616 Wrocław, Poland.
Department of Biotechnology and Food Microbiology, Faculty of Biotechnology and Food Science, Wrocław University of Environmental and Life Sciences, Chełmońskiego 37, 51-630 Wrocław, Poland.
Materials (Basel). 2025 Jul 10;18(14):3256. doi: 10.3390/ma18143256.
Reprocessing lignocellulosic waste to obtain new products for industrial purposes is a vital part of circular economy. This paper reports the cellulase production by newly isolated cultured on lignocellulosic agro-industrial by-products, out of which brewer's spent grain (BSG) was selected as most beneficial. Plackett-Burman design was used for screening medium components, while Box-Behnken design was further applied to model the impact of the three most influential variables. The maximum approximated cellulase activity was 0.469 U/mL (1 U = 1 µmol of reducing sugars/1 min), at 48.6 g/L substrate, 5.3 g/L ammonium sulfate, pH 6.1. The partially purified cellulase was characterized, which demonstrated broad range of optimal pH (6.5-9.4), temperature (50-60 °C), and sensitivity to metals. Changes in lignin and pentosans content was demonstrated as a result of BSG hydrolysis with a cell-free cellulase preparation. The produced enzyme was used for hydrolysis of various chemically pretreated (NaOH and HSO) cellulosic substrates, where for reused alkali-pretreated BSG (after microbial enzyme production) the saccharification efficiency was at a level of 25%. The cellulolytic potential of the bacterial strain, along with its resistance to ethanol, present a beneficial combination, potentially applicable to aid saccharification of lignocellulosic by-products for biofuel production.
将木质纤维素废料再加工以获得用于工业目的的新产品是循环经济的重要组成部分。本文报道了新分离的菌株在木质纤维素农工业副产品上培养产生纤维素酶的情况，其中啤酒糟（BSG）被选为最有益的底物。采用Plackett-Burman设计筛选培养基成分，同时应用Box-Behnken设计对三个最具影响力的变量的影响进行建模。在底物浓度为48.6 g/L、硫酸铵浓度为5.3 g/L、pH值为6.1时，最大纤维素酶活性约为0.469 U/mL（1 U = 1 μmol还原糖/1分钟）。对部分纯化的纤维素酶进行了表征，结果表明其具有较宽的最佳pH范围（6.5 - 9.4）、温度范围（50 - 60°C）以及对金属的敏感性。使用无细胞纤维素酶制剂水解BSG后，木质素和戊聚糖含量发生了变化。所产生的酶用于水解各种化学预处理（NaOH和HSO）的纤维素底物，对于再利用的碱预处理BSG（微生物酶生产后），糖化效率达到25%。该细菌菌株的纤维素分解潜力及其对乙醇的耐受性形成了一种有益的组合，有可能用于辅助木质纤维素副产品糖化以生产生物燃料。
