Karahalil Ercan, Demirel Fadime, Evcan Ezgi, Germeç Mustafa, Tari Canan, Turhan Irfan
Department of Food Engineering, Faculty of Engineering, Akdeniz University, 07058 Antalya, Turkey.
Department of Food Engineering, Izmir Institute of Technology, Gulbahce Campus, 35430 Izmir, Turkey.
3 Biotech. 2017 Dec;7(6):361. doi: 10.1007/s13205-017-1004-2. Epub 2017 Oct 3.
Polygalacturonases (PGs), an important industrial enzyme group classified under depolymerases, catalyze the hydrolytic cleavage of the polygalacturonic acid chain through the introduction of water across the oxygen bridge. In order to produce and increase the concentration of this enzyme group in fermentation processes, a new approach called microparticle cultivation, a promising and remarkable method, has been used. The aim of this study was to increase the PG activity of using aluminum oxide (AlO) as microparticles in shake flask fermentation medium. Results indicated that the highest PG activity of 34.55 ± 0.5 U/ml was achieved with the addition of 20 g/L of AlO while the lowest activity of 15.20 ± 0.2 U/mL was obtained in the presence of 0.1 g/L of AlO. In fermentation without microparticles as control, the activity was 15.64 ± 3.3 U/mL. Results showed that the maximum PG activity was 2.2-fold higher than control. Additionally, smaller pellets formed with the addition of AlO where the lowest pellet diameter was 955.1 µm when 10 g/L of the microparticle was used. Also, it was noticed that biomass concentration gradually increased with increasing microparticle concentration in the fermentation media. Consequently, the PG activity was significantly increased in microparticle-enhanced shake flask fermentation. In fact, these promising preliminary data can be of significance to improve the enzyme activity in large-scale bioreactors.
多聚半乳糖醛酸酶（PGs）是一类重要的工业酶，属于解聚酶，通过在氧桥上引入水来催化多聚半乳糖醛酸链的水解断裂。为了在发酵过程中生产并提高这类酶的浓度，一种名为微粒培养的新方法被采用，这是一种有前景且引人注目的方法。本研究的目的是在摇瓶发酵培养基中使用氧化铝（AlO）作为微粒来提高PG的活性。结果表明，添加20 g/L的AlO时，PG的最高活性达到34.55±0.5 U/ml，而在存在0.1 g/L的AlO时，活性最低，为15.20±0.2 U/mL。在不添加微粒作为对照的发酵中，活性为15.64±3.3 U/mL。结果显示，最大PG活性比对照高2.2倍。此外，添加AlO形成了较小的颗粒，当使用10 g/L的微粒时，最小颗粒直径为955.1 µm。同时，还注意到发酵培养基中微粒浓度增加时，生物量浓度逐渐升高。因此，在微粒增强的摇瓶发酵中，PG活性显著提高。事实上，这些有前景的初步数据对于提高大规模生物反应器中的酶活性可能具有重要意义。
