Dept of Chemistry, Pondicherry University, Kalapet, Pondicherry 605014, India.
Microbial Type Culture Collection and Gene Bank (MTCC), CSIR-Institute of Microbial Technology, Chandigarh 160036, India.
Int J Biol Macromol. 2023 Jul 31;244:125428. doi: 10.1016/j.ijbiomac.2023.125428. Epub 2023 Jun 15.
World health organization listed fungi as priority pathogens in 2022 to counter their adverse effects on human well-being. The use of antimicrobial biopolymers is a sustainable alternative to toxic antifungal agents. In this study, we explore chitosan as an antifungal agent by grafting a novel compound N-(4-((4-((isatinyl)methyl)piperazin-1-yl)sulfonyl)phenyl) acetamide (IS). The acetimidamide linkage of IS to chitosan herein was confirmed by C NMR and is a new branch in chitosan pendant group chemistry. The modified chitosan films (ISCH) were studied using thermal, tensile, and spectroscopic methods. The ISCH derivatives strongly inhibit fungal pathogens of agricultural and human importance, namely Fusarium solani, Colletotrichum gloeosporioides, Myrothecium verrucaria, Penicillium oxalicum, and Candida albicans. ISCH80 showed an IC value of 0.85 μg/ml against M. verrucaria and ISCH100 with IC of 1.55 μg/ml is comparable to the commercial antifungal IC values of Triadiamenol (3.6 μg/ml) and Trifloxystrobin (3 μg/ml). Interestingly, the ISCH series remained non-toxic up to 2000 μg/ml against L929 mouse fibroblast cells. The ISCH series showed long-standing antifungal action, superior to our lowest observed antifungal IC values of plain chitosan and IS at 12.09 μg/ml and 3.14 μg/ml, respectively. ISCH films are thus suitable for fungal inhibition in an agricultural setting or food preservation.
世界卫生组织在 2022 年将真菌列为优先病原体，以应对其对人类福祉的不利影响。抗菌生物聚合物的使用是替代有毒抗真菌剂的可持续选择。在这项研究中，我们通过接枝一种新型化合物 N-(4-((4-((异吲哚基)甲基)哌嗪-1-基)磺酰基)苯基)乙酰胺 (IS) 来探索壳聚糖作为一种抗真菌剂。IS 与壳聚糖的乙酰胺键在此通过 C NMR 得到证实，这是壳聚糖侧基化学中的一个新分支。通过热、拉伸和光谱方法研究了改性壳聚糖薄膜 (ISCH)。ISCH 衍生物强烈抑制了农业和人类重要的真菌病原体，即尖孢镰刀菌、胶孢炭疽菌、疣状毛霉、草酸青霉和白色念珠菌。ISCH80 对 M. verrucaria 的 IC 值为 0.85 μg/ml，而 ISCH100 的 IC 值为 1.55 μg/ml，与商业抗真菌剂 Triadiamenol（3.6 μg/ml）和 Trifloxystrobin（3 μg/ml）的 IC 值相当。有趣的是，ISCH 系列在对 L929 小鼠成纤维细胞的毒性测试中，在高达 2000 μg/ml 的浓度下仍保持非毒性。ISCH 系列表现出持久的抗真菌作用，优于我们观察到的最低抗真菌 IC 值，普通壳聚糖和 IS 分别为 12.09 μg/ml 和 3.14 μg/ml。因此，ISCH 薄膜适合在农业环境或食品保存中抑制真菌。
