Related Experiment Video
Updated: Jun 7, 2025
Lignin Down-regulation of Zea mays via dsRNAi and Klason Lignin Analysis
Published on: July 23, 2014
Mechanism underlying V-type structure formation in maize starch through glycerol-ethanol thermal substitution method
Zhijie Zhu1, Kai Du2, Zhiqian Ma1
1Key Laboratory of Jianghuai Agricultural Product Fine Processing and Resource Utilization, Ministry of Agriculture and Rural Affairs, Anhui Engineering Research Center for High Value Utilization of Characteristic Agricultural Products, College of Tea & Food Science and Technology, Anhui Agricultural University, Hefei, China.
None:
V-type starches have been widely used in food science, agriculture, and biomedical science, but their mechanism of formation in nonaqueous solvents remains unclear. This study performed glycerol-ethanol thermal substitution to prepare V-type starch at atmospheric pressure. Scanning electron microscopy and confocal laser scanning microscopy revealed that breakage of starch particles began in the hilum region and rapidly spread to the periphery with the temperature increased from 100 °C to 130 °C. The Maltese crosses of the starch disappeared and starch particles had the form of doughnut-shaped rings when the glycerol temperature was 140 °C. Glycerol temperature was not found to significantly affect the chain length of amylopectin, meaning that glycerol molecules may stabilize the conformation of amylose through hydrogen bonding, promoting the amylose to form a V-type spiral structure. Additionally, A-type crystallinity and double helix structure proportion of the samples significantly decreased from 30.81 % and 42.21 % to 5.70 % and 16.47 % as the temperature of glycerol was increased to 140 °C, whereas the V-type crystallinity and single helix structure proportion of the samples remarkably increased from 13.26 % and 1.05 % to 37.97 % and 25.09 %, respectively. This study provided a facile and versatile approach to effectively regulate the formation of V-type starch.
Related Concept Videos
03:25Chemistry of Carbohydrates
01:38Preparation of Alcohols via Substitution Reactions
Alcohols can be synthesized from alkyl halides via nucleophilic substitution reactions. The highly polar carbon-halogen bond in the substrate makes halide a good leaving group. The hydroxide ion or water can act as a nucleophile to take the place of halide and form an alcohol. The substitution reactions occur via two different reaction pathways, SN1 or SN2, depending on the nature of carbon attached to the halide.
Primary alcohols are synthesized from primary alkyl halides, and the...
![[3,3] Sigmatropic Rearrangement of Allyl Vinyl Ethers: Claisen Rearrangement](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2Ffiles%2Fmedia%2Fscience-education%2Fscience-education-thumbs%2F13097.jpg&w=3840&q=75)
01:24[3,3] Sigmatropic Rearrangement of Allyl Vinyl Ethers: Claisen Rearrangement
01:15Dehydration Synthesis
Dehydration synthesis (also called a condensation reaction) is the chemical process in which two molecules covalently link together to form a new molecule, along with the release of a water molecule. Many physiologically important compounds form by dehydration synthesis reactions, such as complex carbohydrates, proteins, DNA, and RNA.
Synthesis of carbohydrates
Sugar molecules are covalently linked together by dehydration synthesis. During the reaction, the hydroxyl (-OH) group from...
01:15Hydrolysis
Hydrolysis is a chemical reaction in which the addition of water breaks down a polymer into its simpler monomer units. For example, peptides break into amino acids, carbohydrates into simple sugars, and DNA into nucleotides. Enzymes often facilitate these processes.
Hydrolysis Reverses Dehydration Synthesis
Complex carbohydrates can be broken down by breaking the bonds between individual sugar units. The reaction breaks a glycosidic bond as water is added to the compound. The...
01:14Alkylation of β-Diester Enolates: Malonic Ester Synthesis