Modulation of gut microbiota by rice starch enzymatically modified using amylosucrase from Deinococcus geothermalis

Amylosucrase can increase the amount of resistant starch (RS) in starch by transferring glucose from sucrose to amylopectin. Here, rice starch was modified using amylosucrase from Deinococcus geothermalis (DgAS). DgAS-modified rice starch (DMRS) increased the side-chain length of amylopectin and appeared in the form of B-type crystals. In vitro digestion analyses revealed that DMRS had a higher RS contents and lower digestion rate than native rice starch. When high-fat diet (HFD)-induced C57BL/6 mice were orally administered DMRS, body weight and white fat tissues of DMRS-fed HFD mice were not significantly different. However, serum leptin and glucose levels were significantly decreased and serum glucagon like peptide-1was increased in these mice. The cecal microbiome in DMRS-fed HFD mice was identified to investigate the role of DMRS in gut microbiota regulation. DMRS supplementation increased the relative abundance of Bacteroides, Faecalibaculum, and Ruminococcus in mouse gut microbiota.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01238-1.

Enhancing the functional properties of rice starch through biopolymer blending for industrial applications: A review

Rice starch has been used in various agri-food products due to its hypoallergenic properties. However, rice starch has poor solubility, lower resistant starch content with reduced retrogradation and poor functional properties. Hence, its industrial applications are rather limited. The lack of comprehensive information and a holistic understanding of the interaction between rice starch and endo/exogenous constituents to improve physico-chemical properties is a prerequisite in designing industrial products with enhanced functional attributes. In this comprehensive review, we highlight the potentials of physically mixing of biopolymers in upgrading the functional characteristics of rice starch as a raw material for industrial applications. Specifically, this review tackles rice starch modifications by adding natural/synthetic polymers and plasticizers, leading to functional blends or composites in developing sustainable packaging materials, pharma- and nutraceutical products. Moreover, a brief discussion on rice starch chemical and genetic modifications to alter starch quality for the deployment of rice starch industrial application is also highlighted.

Advantages and Disadvantages of Bioplastics Production from Starch and Lignocellulosic Components

The accumulation of plastic wastes in different environments has become a topic of major concern over the past decades; therefore, technologies and strategies aimed at mitigating the environmental impacts of petroleum products have gained worldwide relevance. In this scenario, the production of bioplastics mainly from polysaccharides such as starch is a growing strategy and a field of intense research. The use of plasticizers, the preparation of blends, and the reinforcement of bioplastics with lignocellulosic components have shown promising and environmentally safe alternatives for overcoming the limitations of bioplastics, mainly due to the availability, biodegradability, and biocompatibility of such resources. This review addresses the production of bioplastics composed of polysaccharides from plant biomass and its advantages and disadvantages.

Isolation, modification, and characterization of rice starch with emphasis on functional properties and industrial application: a review

Starch is one of the organic compounds after cellulose found most abundantly in nature. Starch significantly varies in their different properties like physical, chemical, thermal, morphological and functional. Therefore, starch is modified to increase the beneficial characteristics and remove the shortcomings issues of native starches. The modification methods can change the extremely flexible polymer of starch with their modified physical and chemical properties. These altered structural attributes are of great technological values which have a wide industrial potential in food and non-food. Among them, the production of novel starches is mainly one that evolves with new value-added and functional properties is on high industrial demands. This paper provides an overview of the rice starch components and their effect on the technological and physicochemical properties of obtained starch. Besides, the tuned techno-functional properties of the modified starches through chemical modification means are highlighted.HighlightsNative and modified starches varies largely in physicochemical and functional traits.Modified physical and chemical properties of starch can change the extremely flexible polymer of starch.Techno-functional properties of the modified starches through chemical modification means are highlighted.Dual modification improves the starch functionality and increases the industrial applications.Production of novel starches is on high industrial demands because it mainly evolves with new value added and functional properties.

Effects of drying temperature and genotype on morphology and technological, thermal, and pasting properties of corn starch

The objective of this study was to evaluate the effects of drying temperature (30, 50, 70, and 90 °C) and genotype (yellow floury corn, white floury corn, and yellow flint corn) on the morphology and technological and thermal properties of corn starch. The white and yellow genotypes with floury endosperm (soft) had spherical starch granules, while the granules of the yellow flint genotype were polyhedral. White floury corn showed higher extraction yield, higher resistance during granules' swelling before the physical collapse, as it was not affected by the increase in drying temperature, and at 90 °C it presented higher breakdown and energy necessary for gelatinization. There were peak viscosity and gelatinization enthalpy reduction on starch from yellow floury corn and yellow flint corn according to the increase in drying temperature. Drying temperatures below 50 °C are indicated for all genotypes studied. White floury corn is indicated due to the higher extraction yield presented. Yellow floury corn is indicated for application in chilled and frozen products due to lower starch retrogradation. The yellow flint corn is indicated for application as a thickening agent due to higher gel hardness.

Enzymatic extraction of potato starch: A parametric optimization study using response surface methodology

Optimized, effective and efficient methodology has been determined in this research work for the recovery of starch from potatoes. Potato starch extraction experimental results have been utilized for the parametric optimization study by using different statistical techniques. In this research work, starch extraction was conducted by employing cellulase enzyme. Response surface methodology (RSM) was put to use to perform statistical analysis to get optimum results. Five-level central composite design (CCD) consisting of three parameters was implemented to investigate the effect of enzyme concentration, contact time and broth dilution. Experiment results revealed that increment in enzyme concentration and contact time enhanced the starch recovery while dilution showed the inverse relation on the recovery of starch. Optimum starch recovery was achieved upto 89% when enzyme concentration (0.5 g/100 g) of potato meal was diluted with 10 mL of water and mixed for 4 h at 45°C.

Enzymatically elongated rice starches by amylosucrase from Deinococcus geothermalis lead to slow down the glucose generation rate at the mammalian α-glucosidase level

Amylosucrase (AS) catalyzes the transfer of a glucosyl unit from sucrose onto α-1,4-linked glucan polymers in starch. In this study, AS from Deinococcus geothermalis (DgAS) was applied to produce modified rice starches with slowly digestible properties. DgAS-treated waxy and normal rice starches showed significantly (p < 0.05) elevated degrees of polymerization, suggesting that the external chains were elongated. Additionally, the crystalline structures of starches changed from A- to B-type, and the temperature transition properties of enzymatically modified rice starches increased. The amounts of slowly digestible starch (SDS) increased remarkably (20.1% and 18.8%; waxy and normal rice starches, respectively), and the DgAS-treated rice starches were slowly hydrolyzed to glucose at the mammalian mucosal α-glucosidase level. Thus, DgAS-treated rice starches can be used to produce SDS-based ingredients that attenuate the glucose spike after glycemic food ingestion.