Int.J.Curr.Microbiol.App.Sci (2020) 9(12): 3297-3302 3297 Original Research Article https://doi.org/10.20546/ijcmas.2020.912.392 Comparison of Protein Composition of Normal and Quality Protein Maize Poonam Choudhary 1* and Dharam Paul Chaudhary 2 1 ICAR-Central Institute of Post-Harvest Engineering and Technology, Ludhiana, Punjab, India 2 ICAR-Indian Institute of Maize Research, PAU Campus, Ludhiana, Punjab, India *Corresponding author ABSTRACT Introduction Maize (Zea mays L.) popularly known as corn, is one of the most useful emergent cash crops. It is also known as “queen of cereals” globally. The crop has tremendous genetic variability, which enables it to thrive in tropics, sub-tropics and temperate climates. In India, it is the third most essential food cash crops after wheat and rice. Maize is grown throughout the year to provide nutrients and feed for humans and animals and also serve as a raw material for thousands of industries including food sweeteners, pharmaceutical, alcoholic beverages, cosmetics and fuel etc. In India, maize is grown to meet demands of various sectors as it provides about 47% as poultry feed, 20% as direct consumption, 14% as livestock consumption, 12% as starch production, 7% as food processing, brewery and others. The normal maize possesses approximately 8–13% protein, 68–73% starch, 2–3% oil, 2–4% sugar with rest of the material being provided by fibre and minerals International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 9 Number 12 (2020) Journal homepage: http://www.ijcmas.com The endosperm of normal maize is predominates with the zein proteins (prolamins and prolamin-like) which are primarily responsible for poor quality of protein. To overcome such problems researchers have developed quality protein maize (QPM) by modifying the protein profile of normal maize so the present study was taken up to understand the comparative protein composition in kernels of normal and quality protein maize. For this purpose six maize genotypes were evaluated for tryptophan content, endosperm protein and protein fractions viz. albumin and globulins, prolamins, prolamin-like, glutelin-like and glutelins. Approximately 47% higher tryptophan content was observed in QPM genotypes which are result of endosperm modification that alter maize endosperm amino acid profile and composition of maize endosperm protein. In addition, QPM genotypes also had higher albumin, globulins and glutelins fractions as compared to the normal maize. The normal genotypes showed approximately 60% of total protein as zein protein as compared to QPM genotypes having 30% of total protein as zein protein. The presence of opaque-2 gene in QPM genotypes, encodes a transcription factor which reduces the transcription and expression of 22kD alpha-zein protein and increases the non-zein protein fractions. It was concluded that QPM maize possess an improved amino acid profile and endosperm protein composition which ensures the nutritional security. Keywords Maize, Protein fractionation, Quality protein maize, Tryptophan and Zeins Accepted: 28 November 2020 Available Online: 10 December 2020 Article Info