Ping Zhang,Deyi Hou,David O’Connor,Xuanru Li,Simo Pehkonen,Rajender S. Varma,Xun Wang
Many challenges remain for the mass production of nanoparticles for the removal of contaminants from water, primarily due to the complexity of the synthetic protocols involved and the use of hazardous reagents. Although the development of phytosynthetic methods for the green fabrication of nanomaterials have seen keen interest, there remains much scope for improvement in terms of maximizing adsorption capacity and controlling the size of the nanoparticles produced. A green and sustainable pathway is described using Virginia creeper (Parthenocissus quinquefolia) leaf extract in the presence of oxalic acid for the synthesis of earth abundant Fe,Cu-based nanoparticle adsorbents. This optimized green method could produce Fe,Cu-based nanoparticles with a remarkably high maximum adsorptive capacity (1399 mg g–1) for aqueous Malachite Green (MG) removal. Furthermore, various particle sizes (between 160 and 1000 nm) were attained by simply varying the amount of oxalic acid. The synthesized adsorbent displayed other excellent characteristics, including (i) maintaining a high adsorption capacity over a wide range of pH conditions, (ii) remaining chemically stable under an ambient storage environment, and (iii) having good recycling potential, with consistent removal efficiency observed over four adsorption/desorption cycles. This work not only promotes the use of natural, earth-abundant, and renewable resources in synthesizing novel and efficient absorbents but also provides a simple, convenient, and cost-effective strategy for the purification of dye-laden wastewater.
Ultrasound-assisted extraction of Cissus repens polysaccharides (CRPs) was optimized through response surface methodology (RSM) based on Box–Behnken design (BBD). The maximum CRPs yield (16.18%) was achieved under the optimum extraction conditions: extraction time 72 min, extraction temperature 74 ℃, extraction power 240 W. Then three-phase partitioning (TPP) method combined with gradient alcohol precipitation was used to obtained CRP20, CRP40, CRP60 and CRP80 from CRPs, and CRP80 has a higher purity than others. The primary chemical and structural characteristics of CRP80 were investigated by UV, FT-IR, high-performance liquid chromatography (HPLC) and high-performance gel-permeation chromatography (HPGPC). CRP80 is mainly composed of glucose, galactose, arabinose and mannose, with a molecular weights of approximately 2.95 kDa. Furthermore, the antioxidant activity and hypoglyceamic activity of CRP80 in vitro were evaluated. The results showed that CRP80 had strong scavenging activities on ABTS, hydroxyl and DPPH radicals, as well as high scavenging activities on α-glucosidase and α-amylase. Our research provided an efficient method for the extraction of polysaccharides from C. repens and CRP80 has potential as a promising source of natural antioxidants and hypoglycemic agent for the functional food and medicinal industries.
危险品化学品经营许可证（带存储）