title: Biological synthesis of Au nanoparticles using liquefied mash of cassava starch and their functionalization for enhanced hydrolysis of xylan by recombinant xylanase.
abstract: Au nanoparticles (AuNPs) have shown the potential for a variety of applications due to their unique physical and chemical properties. In this study, a facile and affordable method for the synthesis of AuNPs via the liquefied mash of cassava starch has been described and the functionalized AuNPs by L-cysteine improved activity of recombinant xylanase was demonstrated. UV-Vis absorption spectroscopy, transmission electron microscopy, and zeta potential measurements were performed to characterize the AuNPs and monitor their synthesis. The presence of Au was confirmed by energy-dispersive X-ray spectroscopy (EDX) and the X-ray diffraction patterns showed that Au nanocrystals were face-centered cubic. The C=O stretching vibration in the Fourier transform infrared spectrum of AuNPs suggested that the hemiacetal C-OH of sugar molecules performed the reduction of Au³⁺ to Au⁰. The presence of C and O in the EDX spectrum and the negative zeta potential of AuNPs suggested that the biomolecules present in liquefied cassava mash were responsible for the stabilization of AuNPs. The surface of AuNPs was easily functionalized by L-cysteine, which improved the stability of AuNPs. Moreover, cysteine-functionalized AuNPs could significantly improve recombinant xylanase efficiency and stability.
authors: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China.|College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China.
authors: Sumei
authors: S
authors: Zeng
authors: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China.|College of Chemistry and Chemical Engineering, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China.
authors: Liangwei
authors: L
authors: Du
authors: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China.|College of Chemistry and Chemical Engineering, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China.
authors: Meiying
authors: M
authors: Huang
authors: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China. jiaxunfeng@sohu.com.|College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, People's Republic of China. jiaxunfeng@sohu.com.
authors: Jia-Xun
authors: JX
authors: Feng
mesh_terms: D043364:Endo-1,4-beta Xylanases / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006868:Hydrolysis; D002365:Manihot / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D011994:Recombinant Proteins / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D013056:Spectrophotometry, Ultraviolet; D013213:Starch / Q000737:chemistry*; D014990:Xylans / Q000737:chemistry*
chemical_list: D011994:Recombinant Proteins; D014990:Xylans; D006046:Gold; D013213:Starch; D043364:Endo-1,4-beta Xylanases
keywords: Au nanoparticles; Biological synthesis; Functionalization; Liquefied cassava mash; Xylanase