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The digestion of starch have been of great interest, yet little is known about the structure changes and structure-digestibility relationships of waxy rice starch during digestion. In this study, waxy rice starch from Indica and Japonica cultivars were in vitro pre-digested for different times, and the changes in their structure and properties were investigated, including granule morphology, chain length distribution, short-range ordered structure, crystallinity, thermal properties, and digestibility. Pre-digested Indica and Japonica waxy rice starch had the characteristics of porous starch, showing similar surface erosion and pores. With the prolongation of pre-digestion time, the amylose content decreased by 0.74 %-2.69 %, the proportion of amylopectin short A chain (DP6-12) and B 1 chain (DP13-24) decreased, and the proportion of long B 2 (DP25-36) and B 3 chain (DP ≥ 37) increased, especially in pre-digested Indica waxy rice starch. The short- and long-range ordered structure of pre-digested starch increased, manifested by an increase in the absorbance ratio at 1047/1022 cm -1 , a decrease at 1022/995 cm -1 , and an increase in relative crystallinity, leading to higher gelatinization temperature and enthalpy. Pre-digested waxy rice starch had a reduced rapidly digestible starch of 18.27 %-33.93 % and an increased resistant starch of 29.51 %-41.32 %, which will be applied in functional starch and healthy starchy foods., Competing Interests: Declaration of competing interest Authors declared that there are no conflicts of interest to this work., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Fluorescent probe L-I was synthesized to demonstrate that 1,3,4-thiadiazole is an attractive moiety and could be utilized as positive hydrogen bond acceptor for excited state intramolecular proton transfer (ESIPT) processes, guider of electrons movement for intramolecular charge transfer (ICT) process and identify group for mental ions. Furthermore, dicyanoisophorone framework was employed to improve the fluorescence characteristics and near-infrared (NIR) fluorescent emission at 695 nm accompanied by a Stoke's shift as large as 260 nm was obtained. L-I could selectively detect Cu 2+ over other analytes taking advantages of high sensitivity, fast response within 30 s and low detection limit (0.026 μM). More important, L-I exhibited good performance for detection of Cu 2+ in actual water samples, food products, traditional Chinese medicine and for cell imaging which demonstrates practical significance in the fields of environmental monitor, food safety and biotechnology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The present study focused on the extraction of water-soluble dietary fiber (CSDF) and water-insoluble dietary fiber (CIDF) from celery. It investigated their effects on glutinous rice starch's (GRS) physicochemical, structural, and digestive properties. The results showed that as the addition of the two dietary fibers increased, they compounded with GRS to varying degrees, with the complexing index reaching 69.41 % and 60.81 %, respectively. The rheological results indicated that the two dietary fibers reduced the viscosity of GRS during pasting and inhibited the short-term regrowth of starch. The FTIR and XRD results revealed that the two fibers interacted with GRS through hydrogen bonding, effectively inhibiting starch retrogradation. Furthermore, both fibers increased the pasting temperature of GRS, thus delaying its pasting and exhibiting better thermal stability. Regarding digestibility, the starch gels containing dietary fibers exhibited significantly reduced digestibility, with RS significantly increased by 8.15 % and 8.95 %, respectively. This study provides insights into the interaction between two dietary fibers and GRS during processing. It enriches the theoretical model of dietary fiber-starch interaction and provides a reference for the application development of starch-based functional foods., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Radix Cynanchi bungei (RCb) contains 40-70 % starch, yet little is known about the structure and properties of RCb starch. In this study, the multiscale structure of two cultivars of RCb starch (YW201501 and BW201001) were characterized, and the effects of starch structure on its physicochemical properties were investigated. The differences in physicochemical properties of RCb starch were influenced by its multiscale structure. The starch granules were round and irregular polygon, with sizes ranging between 2 and 14 μm. YW201501 had a higher amylose (21.81 %) and lipid (0.96 %) content, molecular weight (59.5 × 10 6  g/mol), and A chain proportion (27.5 %), and a lower average granule size (6.14 μm), amylopectin average chain length (19.7), and B3 chain proportion (10.3 %). Both starches were B-type crystalline, with higher crystallinity (26.3 %) and R 1047/1022 (0.74) for YW201501, resulting in large gelatinization enthalpy. In addition, the higher peak viscosity and larger retrogradation degree of YW201501 were correlated to its higher amylose content. In vitro digestibility revealed that the low rapidly digestible starch and high resistant starch of BW201001 were related to the fine structure of starch. YW201501 and BW201001 had a medium glycemic index (62.6-66.0) with potential for processing into healthy starchy foods., Competing Interests: Declaration of competing interest Authors declared that there are no conflicts of interest to this work., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Alcohol solution is a cheap, simple, and effective precipitating solvent frequently used for separating debranched starch (DBS), yet little is known about the precipitation mechanism of DBS by different alcohols. This study precipitated DBS from pullulanase-hydrolyzed starch using ethanol, n-butanol, and isopentanol. The multiscale structures of DBS were characterized, including chain length, single/double helix, and crystalline. The chain conformation and precipitation mechanism of DBS in different alcohols was investigated using molecular dynamics (MD) simulation. DBS precipitated by n-butanol contained the largest proportion of short chain (DP6-24, 83.2 %), the highest V-type crystallinity (21.1 %), and the largest single-helix content (24.7 %). A single helix conformation of DBS chain was determined in alcohols, where alcohol molecules entered the helix cavity. Intra/inter-molecular hydrogen bonds stabilized the helix, with a large number of hydrogen bonds leading to strong molecular interaction and stable helical structure. The solvent accessible surface area of DBS chain decreased by 7.88-19.32 % in alcohols, and the radial distribution function revealed that the first solvent layer of DBS chain at 0.29 nm was closely related to hydrogen bonding. This study provides a basis for the choice of precipitation solvent for preparing DBS with different chain lengths and physicochemical properties., Competing Interests: Declaration of competing interest Authors declared that there are no conflicts of interest to this work., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this work, Corn Starch (CS)-Lauric acid (LA) complexes prepared by different ultrasound times were explored for multi-scale structure and digestibility. The results showed that the average molecular weight of the CS decreased from 380.478 to 323.989 kDa and the transparency increased to 38.55 % after 30 min of ultrasound treatment. The scanning electron microscope (SEM) results revealed a rough surface and agglomeration of the prepared complexes. The complexing index of the CS-LA complexes increased by 14.03 % compared to the non-ultrasound group. The prepared CS-LA complexes formed a more ordered helical structure and a more dense V-shaped crystal structure through hydrophobic interactions and hydrogen bonding. In addition, fourier transforms infrared spectroscopy and the molecular docking revealed that the hydrogen bonds formed by CS and LA promoted the formation of an ordered structure of the polymer, retarding the diffusion of the enzyme and thus reducing the digestibility of the starch. With correlation analysis, we provided insight into the multi-scale structure-digestibility relationship in the CS-LA complexes, which provided a basis for the relationship between structure and digestibility of lipid-containing starchy foods., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Debranched starch (DBS) has great probability as carrier for bioactive ingredients, but effects of branching degree (DB) on the complex formation of starch remain unclear. This study investigated the potential of DBS with different DB to load lycopene and characterized the structural properties of inclusion complexes. Glutinous rice starch was debranched to get DBS with different molecular weights, where DBS with a branching degree of 11.42 % had the greatest encapsulation efficiency (64.81 %). SEM, particle size, and zeta-potential results showed that the complexes form stable spherical crystals through electrostatic interactions. The structures of complexes were resolved by FTIR, XRD, TGA, and 13 C CP/MAS NMR analytical techniques, indicating that lycopene can be loaded on DBS by the self-assembly through hydrophobic and hydrogen bonding interactions. Degradation experiments revealed that retention of complexes was significantly higher than the unencapsulated one. Our study reveals the structural features of the complex between DBS and lycopene, providing theoretical guidance for developing and producing novel nutraceuticals., Competing Interests: Declaration of competing interest We confirm that the manuscript has been read and approved by all named authors and there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that the order of authors listed in the manuscript has been approved by all of us. The authors declare no competing financial interest. We confirm that the content of the manuscript has not been officially published and there is no such thing as duplicate submission. We have given due consideration to the protection of intellectual property associated with this work and confirm that there are no impediments to publication, including the timing of publication, with respect to intellectual property. In so doing we confirm that we have followed the regulations of our institutions concerning intellectual property. No human or animal studies are presented in this manuscript., (Copyright © 2023. Published by Elsevier B.V.)

High amylose corn starch (HACS)-oat β-glucan (OBG) complex was prepared by ball milling treatment. The morphology and structure of the samples were characterized, and the digestibility of the samples was studied. SEM analysis showed that the grain structure of oat β-glucan-starch after ball milling showed an irregular aggregate shape. The rheological results indicated that the apparent viscosity of the solution of HACS-OBG complex prepared by ball milling, with the values of both G' and G″ decreasing on the increase of OBG addition. Multi-scale structure analysis showed that the disorder of the crystal structure and short-range structure of the HACS-OBG complex would lead to the decrease of the double helix structure content. In terms of digestibility, the RDS of the complex decreased from 75.88 % to 66.26 %, which suppressed the digestibility of starch. Molecular docking and quantum chemistry techniques further demonstrated the strong hydrogen bond interaction between HACS and OBG and the inhibition rate of OBG on the enzyme, which was conducive to the slow digestion of HACS-OBG complex. Therefore, ball milling treatment can promote the binding of OBG to starch, which may be an effective method for postprandial blood glucose control., Competing Interests: Declaration of competing interest All authors declare that there is no conflict of interest., (Copyright © 2022. Published by Elsevier B.V.)