STARCH INCLUSION COMPLEX WITH L - PHENYLALANINE AND L - TYROSINE

• Main Author: FERNITA NURHAINI NIM : 10514063, FENI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/27283
• Institution: Institut Teknologi Bandung

L <br /> <br /> - <br /> <br /> phenylalanine and L <br /> <br /> - <br /> <br /> tyrosine are amino acids <br /> <br /> which are <br /> <br /> needed as protein <br /> <br /> – <br /> <br /> building molecule <br /> <br /> s. F <br /> <br /> or <br /> <br /> example, these amino acids construct neurotransmitters which act as chemical messengers between the <br /> <br /> brain and the rest of the <br /> <br /> neural network <br /> <br /> s <br /> <br /> . Both <br /> <br /> amino acids <br /> <br /> are hydrophobic <br /> <br /> molecules <br /> <br /> which potentiall <br /> <br /> y <br /> <br /> can be complexed with <br /> <br /> starch. <br /> <br /> In this research, starch was isolated from cassava, with rendemen of 6% <br /> <br /> and amylose content of 15,8%. The inclusion complex were <br /> <br /> prepared by mixing <br /> <br /> the starch solution with <br /> <br /> amino acids at 85 °C for 2, 3, 5, and 6 hours. The optimum complexation time was 5 hours for the <br /> <br /> starch <br /> <br /> – <br /> <br /> L <br /> <br /> - <br /> <br /> tyrosine <br /> <br /> complex <br /> <br /> es <br /> <br /> and 6 hours for the <br /> <br /> starch <br /> <br /> – <br /> <br /> L <br /> <br /> - <br /> <br /> phenylalanine <br /> <br /> complex <br /> <br /> es <br /> <br /> . In this stu <br /> <br /> dy amino acid <br /> <br /> concentrations were <br /> <br /> varied <br /> <br /> from 10%, 15%, to 25% (w/w based on the weight of starch). The resulting <br /> <br /> complexes were characterized by FTIR (Fourier <br /> <br /> - <br /> <br /> Transform Infrared Spectroscopy), XRD (X <br /> <br /> - <br /> <br /> Ray Powder <br /> <br /> Diffraction, SEM (Scanning Electron Microscope), and TGA (Thermogravimetric Analysis <br /> <br /> ). Based on <br /> <br /> FTIR data, the vibration <br /> <br /> peak <br /> <br /> of <br /> <br /> the guest molecules were <br /> <br /> not visible in complex <br /> <br /> es <br /> <br /> . In addition, the <br /> <br /> complexation caused a shift of C <br /> <br /> - <br /> <br /> H and C <br /> <br /> - <br /> <br /> O vibration of starch. This indicated that amino acids were <br /> <br /> encapsulated inside the chanel of the amyl <br /> <br /> ose component of starch. XRD results showed that the two <br /> <br /> complexes were formed which were evidenced by the appearance of the diffraction peaks at 2&#952; of 14,4 <br /> <br /> o <br /> <br /> ; <br /> <br /> 17,1 <br /> <br /> o <br /> <br /> ; 21,1 <br /> <br /> o <br /> <br /> for the <br /> <br /> starch <br /> <br /> – <br /> <br /> L <br /> <br /> - <br /> <br /> tyrosine <br /> <br /> supernatant (PTS) 15% w/w complex, while for <br /> <br /> starch <br /> <br /> – <br /> <br /> L <br /> <br /> - <br /> <br /> phenylalanine <br /> <br /> supernatant (PFS) complexes appeared at 2&#952; of 14,8 <br /> <br /> o <br /> <br /> ; 21,3 <br /> <br /> o <br /> <br /> for 10% w/w, 2&#952; of 14,5 <br /> <br /> o <br /> <br /> and <br /> <br /> 20,7 <br /> <br /> o <br /> <br /> for 25% w/w then in the <br /> <br /> starch <br /> <br /> – <br /> <br /> L <br /> <br /> - <br /> <br /> phenylalanine <br /> <br /> pellet (PFP) complex 15% appears at 2&#952; of 15,2 <br /> <br /> o <br /> <br /> and 21,3 <br /> <br /> o <br /> <br /> . The SEM micrograph showed that th <br /> <br /> e complexes formed have a morphology of fiber and <br /> <br /> lamella, which may be affected by the heating process and the number of the included guest molecules. <br /> <br /> TGA results showed that the PTS 10% w/w complex was degraded at <br /> <br /> 237,3&#8210;338,7 <br /> <br /> °C, while the PFS 10% <br /> <br /> w/w co <br /> <br /> mplex began to degrade over a temperature range of 169 <br /> <br /> – <br /> <br /> 227,6 °C, then 251,6 <br /> <br /> – <br /> <br /> 342,6 °C, and <br /> <br /> 411 <br /> <br /> – <br /> <br /> 507,9 <br /> <br /> o <br /> <br /> C. The degradation test of the complexes which were carried out using &#945; <br /> <br /> - <br /> <br /> amylase enzyme <br /> <br /> showed that the activity of the enzyme was less compared to the one <br /> <br /> s <br /> <br /> using native starch as substrate. <br /> <br /> This suggested that the complexation affected the starch degradation. These starch <br /> <br /> – <br /> <br /> amino acids <br /> <br /> complexes showed potential application of starch as edible molecular carrier of amino acid <br /> <br /> s <br /> <br /> .