Acid hydrolysis of amylose granules and effect of molecular weight on properties of ethanol precipitated amylose nanoparticles

Statistical-Based Optimization of Modified Mangifera indica Fruit Starch as Substituent for Pharmaceutical Tableting Excipient

This study aimed to optimize modified starch from Mangifera indica (mango) fruit using acid hydrolysis and pre-gelatinization via computer-assisted techniques as a substituent for pharmaceutical tableting excipients. The hydrolysis and microwave-assisted pre-gelatinization time and temperature were optimized using a three-level factorial design. The modified starches were characterized for flowability, compressibility, and swelling properties. It was found that all parameters fit a quadratic model, which can be used to predict the properties of the modified starch. The optimized hydrolysis reaction was 3.8 h at 56.4 °C, while the pre-gelatinization reaction was 3 min at 150 °C. Structural changes were found, ascertaining that starch modification was successful. The optimized hydrolyzed starch showed superior properties in relative to unmodified M. indica fruit starch and comparable characteristics to conventional excipients. The optimized pre-gelatinized starch presented an excellent enhancement in the flow and compression properties, with %swelling greatly augmented 3.95-fold and 1.24-fold compared to unmodified starch and SSG, respectively. Additionally, the pre-gelatinized starch presented comparable binding effect, while the hydrolyzed powder had reduced binding capacity due to shorter chains. The findings revealed that the use of software-assisted design of experiment facilitated a data-driven approach to optimize the modifications. The optimized modified mango starch demonstrated potential as a multifunctional excipient, capable of functioning as binder, disintegrant, and diluent.

Combined role of stearic acid and maleic anhydride in the development of thermoplastic starch-based materials with ultrahigh ductility and durability

The diverse properties reported for starch-based materials indicate their potential for use in the preparation of biodegradable flexible actuators. However, their natural brittleness and lack of durability after modification limit their practical application. Therefore, we propose a strategy for preparing flexible starch-based composites. The results of macro/micro property characterizations and molecular dynamics simulations indicated that using starch, maleic anhydride, and stearic acid (SA), the mobility of the starch chains was enhanced and retrogradation was inhibited through the synergistic effects induced by chain breaking, complex formation with SA, and esterification of the starch molecules. In addition, the elongation at break of the modified starch (MS) reached 2070 %, and considerable ductility (>1000 %) as well as well-complexed structure were maintained after six months. Furthermore, the MS was able to undergo self-healing after fracture or a temperature-controlled stiffness transition. Moreover, it underwent complete degradation in soil within 30 d. Finally, an actuator was prepared by doping the MS with nano-Fe3O4 particles to realize a dual magnetic and optical response. Dynamic monitoring was also achieved based on the electrical signal, thereby demonstrating the broad application scope of this material in the development of biodegradable flexible actuators.

Understanding the improvement of sorghum starch acid hydrolysis modification by E-beam irradiation: A supramolecular structure perspective

To investigate the effect of E-beam irradiation (EBI) on acid-hydrolyzed starch, sorghum starch was pretreated with EBI (2, 4, and 8 kGy) and further hydrolyzed using hydrochloric acid (1 % and 6 % concentrations) in this study. EBI intensified acid hydrolysis corrosion on starch granule surfaces without inducing changes in the growth ring, FT-IR spectra, and crystal type (A-type). Also, EBI promoted starch degradation by acid hydrolysis, as evidenced by the R1047/1022 loss (1.071 to 1.027), the molecular weight decrease, and the chain length distribution shift (toward short A-chain). Moreover, this synergistic modification induced a starch enthalpy decrease (only 9.49 J/g) and crystallinity reduction (29.87 %), while solubility increase (34.27 %) and swelling power inhibition (only 7.65 g/g) were observed. Notably, starch digestibility was improved after synergistic modification. The obtained results broaden the processing depth of EBI in modified starch and highlight the promising application of acidolysis sorghum starch as a potential industrial starch.

Structural characterization of different starch-fatty acid complexes and their effects on human intestinal microflora

Resistant starch type 5 (RS5), a starch-lipid complex, exhibited potential health benefits in blood glucose and insulin control due to the low digestibility. The effects of the crystalline structure of starch and chain length of fatty acid on the structure, in vitro digestibility, and fermentation ability in RS5 were investigated by compounding (maize, rice, wheat, potato, cassava, lotus, and ginkgo) of different debranched starches with 12-18C fatty acid (lauric, myristic, palmitic, and stearic acids), respectively. The complex showed a V-type structure, formed by lotus and ginkgo debranched starches, and fatty acid exhibited a higher short-range order and crystallinity, and lower in vitro digestibility than others due to the neat interior structure of more linear glucan chains. Furthermore, a fatty acid with 12C (lauric acid)-debranched starches complexes had the highest complex index among all complexes, which might be attributed to the activation energy required for complex formation increased with the lengthening of the lipid carbon chain. Therefore, the lotus starch-lauric acid complex (LS12) exhibited remarkable ability in intestinal flora fermentation to produce short-chain fatty acid (SCFAs), reducing intestinal pH, and creating a favorable environment for beneficial bacteria.

Comparison of structural and functional properties of maize starch produced with commercial or endogenous enzymes

To explore an effective and economic method to prepare higher contents of resistant starch (RS), different enzyme treatments including single pullulanase (PUL), commercial α-amylase (AA) or/and β-amylase (BA) with PUL, and malt endogenous amylase (MA) with PUL were used and the structural, physicochemical properties and digestibility of all modified starches (MS) were compared. All the enzyme-treated starches displayed a mixture of B and V-type diffraction patterns. The MA/PUL-MS showed higher V-type diffraction peak intensity as compared to other modified starches. Compared to the combination of commercial enzyme treatment, the combination of malt enzyme treatment led to higher apparent amylose contents (45.56%), RS content (53.93%) and thermal stability (302 °C), whereas it possessed lower solubility indices and predicted glycaemic index. The apparent viscosity and shear resistance of MA/PUL-MS were lower than that of AA/PUL-MS, whereas that of MA/PUL-MS was higher than that of BA/PUL-MS and BA/AA/PUL-MS. These findings would provide a theoretical and applicative basis to produce foods with lower GI in industrial production.

Application of starch-based nanoparticles and cyclodextrin for prebiotics delivery and controlled glucose release in the human gut: a review

Starches are a major constituent of staple foods and are the main source of energy in the human diet (55-70%). In the gastrointestinal tract, starches are hydrolyzed into glucose by α-amylase and α-glucosidase, which leads to a postprandial glucose elevation. High levels of blood glucose levels over sustained periods may promote type 2 diabetes mellitus (T2DM) and obesity. Increasing consumption of starchy foods with a lower glycemic index may therefore contribute to improved health. In this paper, the preparation and properties of several starch-based nanoparticles (SNPs) and cyclodextrins (CDs) derivatives are reviewed. In particular, we focus on the various mechanisms responsible for the ability of these edible nanomaterials to modulate glucose release and the gut microbiome in the gastrointestinal tract. The probiotic functions are achieved through encapsulation and protection of prebiotics or bioactive components in foods or the human gut. This review therefore provides valuable information that could be used to design functional foods for improving human health and wellbeing.