Soumya M P, Nampoothiri K Madhavan
Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Trivandrum, Kerala 695 019 India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002 India.
3 Biotech. 2023 Sep;13(9):308. doi: 10.1007/s13205-023-03718-5. Epub 2023 Aug 21.
This work engrosses the production and further chemical modifications of EPS produced by BR2 and subsequent evaluation of their biological properties showed greater antioxidant properties for the derivatives compared to its native unmodified form. Of the three derivatives, acetylated EPS (a-EPS), carboxymethylated EPS (Cm-EPS), and sulphated EPS (s-EPS), a-EPS exhibited the highest DPPH radical scavenging and total antioxidant activity in a dose-dependent manner. At all tested concentrations, a-EPS showed higher scavenging activity, and a maximum activity of 73.81% at 2 mg/mL. Meanwhile, s-EPS showed the highest reducing power potential and hydroxyl radical scavenging activities. At 2 mg/mL concentration, the order of reducing power was observed to be s-EPS (41.39%) > a-EPS (37.43%) > Cm-EPS (24.02) > BR2 control EPS (16%) and the hydroxyl radical scavenging activity for the s-EPS was 54.43%. The highest reducing power activity exhibited by s-EPS is 2.6-fold higher and a 1.5-fold increase in the scavenging activity of native BR2 EPS after the sulphonyl group addition was observed. The increase in these activities is due to the addition of various functional groups that contributes largely to the scavenging abilities of different free radicals. The s-EPS and Cm-EPS derivatives also exhibited increased cholesterol-lowering activity of 40 and 34.5%, respectively, than the native EPS. Interestingly, there were hardly any inhibitions on cell growth and viability of normal L929 fibroblast cell lines upon treatment with these EPSes. The improved antioxidant properties resulting from chemical modification opened better avenues for EPS application in the food and pharma sectors. Thus, the potentiality of chemically modified EPS may be explored further in the development of functional foods.
The online version contains supplementary material available at 10.1007/s13205-023-03718-5.
这项工作专注于BR2产生的胞外多糖（EPS）的生产及其进一步的化学修饰，随后对其生物学特性的评估表明，与未修饰的天然形式相比，衍生物具有更强的抗氧化性能。在三种衍生物中，乙酰化EPS（a-EPS）、羧甲基化EPS（Cm-EPS）和硫酸化EPS（s-EPS），a-EPS以剂量依赖的方式表现出最高的DPPH自由基清除能力和总抗氧化活性。在所有测试浓度下，a-EPS均表现出更高的清除活性，在2mg/mL时最大活性为73.81%。同时，s-EPS表现出最高的还原能力和羟基自由基清除活性。在2mg/mL浓度下，观察到还原能力的顺序为s-EPS（41.39%）＞a-EPS（37.43%）＞Cm-EPS（24.02）＞BR2对照EPS（16%），s-EPS的羟基自由基清除活性为54.43%。s-EPS表现出的最高还原能力活性比添加磺酰基后天然BR2 EPS的清除活性高2.6倍，增加了1.5倍。这些活性的增加是由于添加了各种官能团，这些官能团在很大程度上有助于清除不同的自由基。s-EPS和Cm-EPS衍生物的降胆固醇活性也分别比天然EPS提高了40%和34.5%。有趣的是，用这些EPS处理后，对正常L929成纤维细胞系的细胞生长和活力几乎没有抑制作用。化学修饰带来的抗氧化性能改善为EPS在食品和制药领域的应用开辟了更好的途径。因此，在功能性食品的开发中可以进一步探索化学修饰EPS的潜力。
在线版本包含可在10.1007/s13205-023-03718-5获取的补充材料。
