Mondéjar-López María, García-Simarro María Paz, Gómez-Gómez Lourdes, Ahrazem Oussama, Niza Enrique
Instituto Botánico, Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
Facultad de Farmacia, Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha, C/José María Sánchez Ibáñez s/n, 02008 Albacete, Spain.
Polymers (Basel). 2025 Jul 25;17(15):2031. doi: 10.3390/polym17152031.
Biogenic silver nanoparticles (AgNPs) were synthesized via a green chemistry strategy using wheat extract and subsequently functionalized with a carboxymethyl chitosan-cinnamaldehyde (CMC=CIN) conjugate through covalent imine bonding. The resulting nanohybrid (AgNP-CMC=CIN) was extensively characterized to confirm successful biofunctionalization: UV-Vis spectroscopy revealed characteristic cinnamaldehyde absorption peaks; ATR-FTIR spectra confirmed polymer-terpene bonding; and TEM analysis evidenced uniform nanoparticle morphology. Dynamic light scattering (DLS) measurements indicated an increase in hydrodynamic size upon coating (from 59.46 ± 12.63 nm to 110.17 ± 4.74 nm), while maintaining low polydispersity (PDI: 0.29 to 0.27) and stable surface charge (zeta potential ~ -30 mV), suggesting colloidal stability and homogeneous polymer encapsulation. Antifungal activity was evaluated against Fusarium oxysporum, Penicillium citrinum, Aspergillus niger, and Aspergillus brasiliensis. The minimum inhibitory concentration (MIC) against F. oxysporum was significantly reduced to 83 μg/mL with AgNP-CMC=CIN, compared to 708 μg/mL for uncoated AgNPs, and was comparable to the reference fungicide tebuconazole (52 μg/mL). Seed priming with AgNP-CMC=CIN led to improved germination (85%) and markedly reduced fungal colonization, while maintaining a favorable phytotoxicity profile. These findings highlight the potential of polysaccharide-terpene-functionalized biogenic AgNPs as a sustainable alternative to conventional fungicides, supporting their application in precision agriculture and integrated crop protection strategies.
通过绿色化学策略，利用小麦提取物合成了生物银纳米颗粒（AgNPs），随后通过共价亚胺键合，用羧甲基壳聚糖 - 肉桂醛（CMC = CIN）共轭物对其进行功能化。对所得的纳米杂化物（AgNP - CMC = CIN）进行了广泛表征，以确认生物功能化成功：紫外可见光谱显示出特征性的肉桂醛吸收峰；衰减全反射傅里叶变换红外光谱（ATR - FTIR）证实了聚合物 - 萜烯键合；透射电子显微镜（TEM）分析证明了纳米颗粒形态均匀。动态光散射（DLS）测量表明，包覆后流体动力学尺寸增加（从59.46±12.63纳米增加到110.17±4.74纳米），同时保持低多分散性（PDI：0.29至0.27）和稳定的表面电荷（ζ电位约为 - 30 mV），表明胶体稳定性和聚合物均匀包封。评估了对尖孢镰刀菌、桔青霉、黑曲霉和巴西曲霉的抗真菌活性。AgNP - CMC = CIN对尖孢镰刀菌的最低抑菌浓度（MIC）显著降低至83μg/mL，相比之下，未包覆的AgNPs为708μg/mL，与参考杀菌剂戊唑醇（52μg/mL）相当。用AgNP - CMC = CIN进行种子引发可提高发芽率（85%）并显著减少真菌定殖，同时保持良好的植物毒性特征。这些发现突出了多糖 - 萜烯功能化生物银纳米颗粒作为传统杀菌剂可持续替代品的潜力，支持它们在精准农业和综合作物保护策略中的应用。
