Department of Food Technology, University Institute of Chemical Technology, North Maharashtra University, Jalgaon 425001, India.
Plant Stress Physiology and Biotechnology Section, Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India.
Int J Biol Macromol. 2019 Jun 15;131:435-444. doi: 10.1016/j.ijbiomac.2019.03.072. Epub 2019 Mar 12.
Chitosan, a functional biopolymer, was irradiated with 100 kGy gamma irradiation and used to access its physical, antioxidant, plant growth promoting and antimicrobial properties. The molecular weight of chitosan reduced to 82.2 kDa from 337.7 kDa after irradiation. UV-Vis spectroscopy and FTIR results revealed slight changes in chitosan skeleton after irradiation but the degree of acetylation of both chitosan was ~18%. DSC profile indicated a prominent decline in enthalpy and energy for phase transition, TGA indicated shift in decomposition temperature, while XRD analysis showed a reduction in chitosan crystallinity after irradiation. DPPH and ABTS radical scavenging activity of chitosan (2-10 mg/mL) enhanced significantly by 1.25-1.45 and 1.80-3.14 folds after irradiation. There was a considerable improvement in morphological parameters (number of leaves, nodes, height, fresh weight and dry weight) and biochemical parameters (chlorophyll, total soluble sugars and soluble proteins content) of in vitro potato plant in chitosan supplemented medium at 75 mg/L concentration than the control. The minimum inhibitory concentration of normal and irradiated chitosan for Alternaria spp. was 2500 and 2000 mg/L and for Fusarium spp. was 1750 and 1500 mg/L, respectively. IC value of normal and irradiated chitosan for Fusarium spp. was 1387.9 ± 9.2 and 954.3 ± 6.1 mg/L, and for Alternaria spp. was 1536.1 ± 24.3 and 1416.8 ± 3.5 mg/L, respectively.
壳聚糖是一种功能生物聚合物，经 100kGy 伽马射线辐照后用于研究其物理性质、抗氧化、促进植物生长和抗菌性能。辐照后壳聚糖的分子量从 337.7kDa 降低到 82.2kDa。紫外可见光谱和傅里叶变换红外光谱结果表明辐照后壳聚糖骨架略有变化，但两种壳聚糖的乙酰化程度均约为 18%。差示扫描量热法谱图表明相变焓和能量显著下降，热重分析表明分解温度发生偏移，而 X 射线衍射分析表明辐照后壳聚糖结晶度降低。壳聚糖（2-10mg/mL）的 DPPH 和 ABTS 自由基清除活性在辐照后分别增强了 1.25-1.45 倍和 1.80-3.14 倍。在 75mg/L 浓度的壳聚糖补充培养基中，体外马铃薯植株的形态参数（叶片数、节点数、高度、鲜重和干重）和生化参数（叶绿素、总可溶性糖和可溶性蛋白含量）得到了显著改善，优于对照组。正常壳聚糖和辐照壳聚糖对链格孢属的最低抑菌浓度分别为 2500 和 2000mg/L，对镰刀菌属的最低抑菌浓度分别为 1750 和 1500mg/L。正常壳聚糖和辐照壳聚糖对镰刀菌属的 IC 值分别为 1387.9±9.2 和 954.3±6.1mg/L，对链格孢属的 IC 值分别为 1536.1±24.3 和 1416.8±3.5mg/L。
