Y-Zeins

RP-HPLC of storage proteins can also predict quality in other cereals. In barley, RP-HPLC of hordeins [112,224] and high-MW glutelins [225] can reveal malting quality. In maize, Paulis et al. [226] showed by RP-HPLC that there are more y-zeins in quality protein maize than in normal maize this relates to lysine content and nutritional quality. RP-HPLC can relate protein composition to kernel hardness, density, and vitreosity of both normal maize and quality protein maize genotypes [227-229]. Differences between alcohol-soluble proteins of hard and soft endosperm of normal and quality protein maize show that the zein distribution influences kernel texture and hardness [230-232]. 

Figure 11.10. Effect of pH and zein type on zein gela tion time. 1 — zein sample rich in a-zein at pH=12,2 -zein sample rich in y-zein at pH=2, 3 — zein sample rich in y-zein at pH=6,4 — zein sample rich in y-zein at pH= 12. [Data from P Nonthaniun, Y Lee, G W Padua, J. Cereal Sci., 58, 76-81 (2013).]...

Mixture of water and ethanol is the best solvent for zein." Zein, a com protein, is a mixture of the polypeptides a-, y-, P-, and 5-zein, with a- and y-zeins comprising 70-85% and 10-20% of total zein respectively." Figure 11.10 shows that concentration of ethanol affects gelation time (as well as the flow behavior) of zein solutions, but there is also observed substantial influence of pH." The last is explained by chemical stractures of different zeins. a-Zein solutions were nearly Newtonian while those containing y-zein showed shear thinning behavior." It is because high pH promotes formation of disulfide bonds in y-zein because y-zein is rich in cysteine which contributes to formation of these bonds."... 

Yong, Y.H., Yamaguchi, S., Gu, Y.S., Mori, T., Matsumura, Y. 2004. Effects of enzymatic deamidation by protein-glutaminase on structure and functional properties of a-zein. J Agric Food Chem 52 7094—7100. 

Dong J., Sun Q., Wang J-Y. Basic study of corn protein, zein, as a biomaterial in tissue engineering, surface morphology and biocompatibility. Biomaterials 25 4691-4691 (2004). 

Synthetic peptide inhibitors have been developed for a variety of proteases [199-204]. Peptide inhibitors of the metalloprotease angiotensin I converting enzyme (ACE) are of major importance as hypertensive agents [13, 31]. A variety of peptides derived from protease-catalyzed hydrolysis of com cc-zein [202-203] or of wheat germ protein [199, 204] inhibit ACE (Table 6). The most potent of such plant-derived ACE inhibitory peptides is Ile-Val-Tyr (IVY) (Ki 0.1 xM) [199, 204], Further plant-derived peptide ACE inhibitors include the tripeptide glutathione [73, 82], the glutathione -related peptide Y-L-glutamyl-(+)-allyl-L-cysteine sulphoxide [73, 82, 200, 201] and the tripeptide His-His-Leu (HHL) from fermented soybean [201] (Table 6). 

Refs. [i]EndresF, Zein El Abedin S (2006) Phys Chem Chem Phys 8 2101 [ii] Ohno Y (2005) Electrochemical aspects of ionic liquids. Wiley, New Jersey... 

Several other polyamides are derived from natural poly(amino acids) that are subject to a subsequent synthetic treatment. Examples are casein, groundnut protein fiber, and zein, which after a treatment with formaldehyde led to new materials with better mechanical/solubility properties. For example, casein is a mixture of several proteins that forms 3% of milk (as casein calcium salt). Casein can be fractionated into simpler proteins designated as a, 3, y, and k [37]. The amino acid content of casein is similar to... 

El-Zein A, Nuwayhid I, El-Fadel M et al (2007) Did a ban on diesel-fuel reduce emergency respiratory admissions for children Sci Total Environ 384 134—140 Erel Y, Axelrod T, Veron A et al (2002) Ttansboundary atmospheric lead pollutiotL Environ Sd Technol 36 3230-3233... 

Jiang, Q.R., Reddy, N., Yang, Y.Q., 2010. Cytocompatible cross-linking of electrospun zein fibers for the development of water-stahle tissue engineering scaffolds. Acta Biomaterialia 6 (10), 4042-4051. 

Zein S, Kulik LV, Yano J, Kem J, Pushkar Y, Zouni A, Yachandra VK, Lubitz W, Neese F, Messinger J (2008) Philos Trans R Soc Lond B Biol Sci 363 1167... 

Jiang, Y.-N., Mo, H.-Y, and Yu, D.-G. (2012) Electrospun drug-loaded core-sheath PVP/zein nanofibers for biphasic drug release. Int. J. Pharm., 438, 232-239. 

Hoffman, K. L., Han, I. Y, and Dawson, P. L. 2000. Antimicrobial effects of com zein films impregnated with nisin, lauric acid, and EDTA. Journal of Food Protection, 64 885-889. 

See dicyclohexyl-, di(2-ethylbutyl)-, di(2-ethylhexyl)-, di(2-ethylhexyl)-4-thio-, di-n-hexyl-y diisobutyl-, and diisooctyl azelates. Azeotrope a-ze-o- trop [a- + zeo- (ff. Gk zein to boil) -h -trope] (1938) n, A liquid mixture that is characterized by a constant minimum or maximum boiling point which is lower or higher than any of the components, and that distills without change in composition. Goldberg DE (2003)... 

Dhandayuthapani B, Poulose AC, Nagaoka Y, Hasumura T, Yoshida Y, Maekawa T, Kumar DS (2012) Biomimetic smart nanocomposite in vitro biological evaluation of zein electrospun fluorescent nanofiber encapsulated CdS quantum dots. Biofabrication 4 025008... 

Unnithan, A.R., Gnanasekaran, G., Sathishkumar, Y., Lee, Y.S., Kim, C.S., 2014. Electro-spun antibacterial polyurethane-ceUulose acetate-zein composite mats for wound dressing. Carbohydrate Polymers 102, 884-892. http //dx.doi.Org/10.1016/j.carbpol.2013. 10.070. 

Luo Y, Zhang B, Whent M, Yu L, Wang Q. Preparation and chmacterization of zein/chitosan complex for encapsulation of a-tocopherol, and its in vitrocontrolled release study. Colloids Surf B Biointerfaces. 2011 85(2) 145-52. 

Luo Y, Zhang B, Cheng WH, Wang Q. Preparation, characterization and evaluation of selenite-loaded chitosan/TPP nanoparticles with or without zein coating. Carbohydr Polym. 2010 82(3) 942-51. 

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