Extraction of Starch from Different Natural Sources and their Characterization by Advanced Spectroscopic Techniques

Abstract

The naturally occurring polymer serves as the principal polysaccharide source for human energy production. The aim of this research was to extract starch polymer as a whole from lentil (Lens culinaris) and barnyard millet (Echinochloa esculenta), by using an alkali pretreatment with sodium hydroxide at 25 ºC. Extracted starches were characterized by spectroscopic techniques as Nuclear magnetic resonance (NMR), Mass Spectroscopy (MS). The extraction process was optimized to ensure high yield and purity by employing methods such as water soaking, sedimentation, and filtration. The extracted starch samples were subjected to structural and molecular analysis using Nuclear Magnetic Resonance (NMR) spectroscopy and mass spectrometry (MS). NMR provided insights into the molecular arrangement and amylose-to-amylopectin ratio, while MS revealed the molecular weight distribution and fragmentation patterns, further elucidating the composition of the starch. The NMR confirmed the presence of hydroxyl and carbonyl group. This obtained starch is suitable for various industrial applications, including food, pharmaceutical and biodegradable materials. The findings contribute to the understanding of lentil and barnyard millet starches potential as alternative starch sources with tailored properties for specific applications. This comprehensive characterization underscores the importance of integrating extraction processes with modern analytical techniques to better understand and exploit the potential of natural starches.