Increase In Resistant Starch Content Research Articles

Changes of crystalline structure and physicochemical properties of Pueraria lobata var. thomsonii starch under water deficit.

Crystal type is an important physicochemical property of starch. However, it is currently unclear whether changes in crystal type affect other properties of starch. This study discovered that water deficit resulted in an increase in small starch granules and transparency in Pueraria lobata var. thomsonii, while causing a decrease in amylose content and swelling power. Additionally, the crystal type of P. Thomsonii starch changed from CB-type to CA-type under water deficit, without significantly altering the short-range ordered structure and chain length distribution of starch. This transformation in crystal type led to peak splitting in the DSC heat flow curve of starch, alterations in gelatinization behavior, and an increase in resistant starch content. These changes in crystalline structure and physicochemical properties of starch granules are considered as adaptive strategies employed by P. Thomsonii to cope with water deficit.

Effect of osmotic pressure and simultaneous heat-moisture phosphorylation treatments on the physicochemical properties of mung bean, water caltrop, and corn starches

This study aimed to investigate the physicochemical properties of modified starch prepared through the simultaneous heat-moisture and phosphorylation treatment (HMPT) and osmotic pressure treatment (OPT) for water caltrop starch (WCS), mung bean starch (MBS), and amylose-rich corn starch (CS) for different time periods. Furthermore, variations in starch content [amylose and resistant starch (RS)], swelling powder (SP), water solubility index (WSI), crystallinity, thermal properties, gelatinization enthalpy (ΔH), and glycemic index (GI) were examined. This study demonstrates that neither HMPT nor OPT resulted in a significant increase in the resistant starch (RS) content, whereas all samples succeeded in heat-treating at 105 °C for another 10 min exhibited a significant increase in RS content compared to their native counterparts. Moreover, the gelatinization temperatures of the three starches increased (To, Tp, and Tc), whereas their gelatinization enthalpy (ΔH) and pasting viscosity decreased. In particular, the GI of all three modified starches subjected to HMPT or OPT showed a decreasing trend with modification time, with OPT exhibiting the best effect. Therefore, appropriate modification through HMPT or OPT is a viable approach to develop MBS, WCS, and CS as processed foods with low GI requirements, which exceptionally may be suitable for canned foods, noodles, and bakery products.

Favored CH-π interaction between enzymatically modified high amylose starch and resveratrol improves digestion resistance

Starch-stilbene polyphenol complexes, a novel form of resistant starch (RS), have received considerable attention due to their potential health benefits. To enhance the functionality of this type of complex, we examined the interactions between resveratrol (RA) and high-amylose starch with different molecular weights, achieved through enzymatic modification followed by high-pressure homogenization (HPH). We examined how these interactions affect the digestibility and ordered structures of the complexes. Our findings reveal that, notwithstanding the inhibition of double helix and B-type crystalline structure formation, RA-starch complexation markedly boosted single helix content, V-type crystalline structure formation, and aggregate structure density. These effects contributed notably to increased RS content. Interestingly, the formation of the V6-type crystalline structure within the complexes was primarily facilitated by the CH-π interaction between the aromatic rings of RA and the C–H of starch, rather than conventional hydrogen bonding and electrostatic forces. The strength of the CH-π interaction increased with higher amylose content and lower molecular weight of the starch, achievable through a 12-h pullulanase hydrolysis followed by a 2-h α-amylase hydrolysis. The resulting HPH-Pα2-RA complexes exhibited remarkable levels of the V-type crystalline structure and RS content, reaching up to 25.45% and 57.37%, respectively. Overall, this study offers valuable insights into the design of starch-polyphenols complexes with a high RS content.

Comparison and inhibition mechanism study on the in vitro digestibility of rice starch complex with soy β-conglycinin and soy glycinin

To inhibit the digestion of indica rice starch (IRS), an excellent strategy was to add exogenous proteins that interact with IRS, which was closely associated with the protein components. Herein, this study compared the effects of soy protein subfractions, soy β-conglycinin (7S) and soy glycinin (11S), on IRS digestion and explored its inhibition mechanisms. This study used hydrothermal processing to prepare IRS complexes with soy protein subfractions (7S and 11S) at different starch-protein ratios. The results found that adding 7S and 11S exhibited different inhibitory patterns on starch digestion. Compared to IRS, a higher slowly digestible starch (SDS) content (40.91%, p < 0.05) was observed at the IRS-7S ratios of 20:8, while the 20:6 IRS-11S complex showed a higher resistant starch (RS) content (15.76%, p < 0.05). Subsequently, the interactions between IRS and soy protein subfractions and their multi-scale structural changes were explored. The rheological results revealed that hydrophobic interaction and hydrogen bonding were the main driving forces. Various structural changes were closely associated with inhibitory modes of soy protein subfractions on IRS digestion. In detail, the increased SDS content in IRS-7S complexes was attributed to the formation of compact protein physical barriers, aggregated structures with more ordered regions, and flexible secondary conformations of 7S. However, the high-density structures and the stable secondary conformations of 11S were responsible for the increased RS content in IRS-11S complexes. Thus, this study could provide directions for developing SDS-enriched or RS-enriched starch-based products.

Impact of cyclic and continuous dry heat modification on the structural, thermal, technological, and in vitro digestibility properties of potato starch (Solanum tuberosum L.): A comparative study

Dry heat treatment (DHT) has been demonstrated as a viable method for starch modification, offering benefits due to its environmentally friendly process and low operational costs. This research modified potato starch using different DHT conditions (continuous-CDHT and cyclic-RDHT), with durations ranging from 3 to 15 h and 1 to 5 cycles, at 120 °C. The study investigated and compared the structural, thermal, pasting, and morphological properties of the treated samples to those of untreated potato starch, including in vitro digestibility post-modification. DHT altered the amylose content of the biopolymer. X-ray diffraction patterns transitioned from type B to type C, and a decrease in relative crystallinity (RC%) was observed. Morphological changes were more pronounced in starches modified by RDHT. Paste viscosities of both CDHT and RDHT-treated starches decreased significantly, by 61.7 % and 58.1 % respectively, compared to native starch. The gelatinization enthalpy of RDHT-treated starches reduced notably, from 17.60 to 16.10 J g−1. Additionally, starch digestibility was impacted, with cyclic treatments yielding a significant increase in resistant starch content, notably an 18.26 % rise. These findings underscore the efficacy of dry heat in enhancing the functional properties of potato starch.

Preparation of the black rice starch-gallic acid complexes by ultrasound treatment: Physicochemical properties, multiscale structure, and in vitro digestibility

This study aimed to investigate the multiscale structure, physicochemical properties, and in vitro digestibility of black rice starch (BRS) and gallic acid (GA) complexes prepared using varying ultrasound powers. The findings revealed that ultrasonic treatment disrupted BRS granules while enhancing the composite degree with GA. The starch granules enlarged and aggregated into complexes with uneven surfaces. Moreover, the crystallinity of the BRS-GA complexes increased to 22.73 % and formed V6-I-type complexes through non-covalent bonds. The increased short-range ordering of the complexes and nuclear magnetic resonance hydrogen (1H NMR) further indicated that the BRS and GA molecules interacted mainly through non-covalent bonds such as hydrogen bonds. Additionally, ultrasound reduced the viscoelasticity of the complexes while minimizing the mass loss of the complexes at the same temperature. In vitro digestion results demonstrated an increase in resistant starch content up to 37.60 % for the BRS-GA complexes. Therefore, ultrasound contributes to the formation of V-typed complexes of BRS and GA, which proves the feasibility of using ultrasound alone for the preparation of starch and polyphenol complexes while providing a basis for the multiscale structure and digestibility of polyphenol and starch complexes.

Effect of processing on resistant starch content of Indian rice varieties (Sona Masuri and Mogra) and its impact on postprandial blood glucose levels

Introduction: Resistant starch has elicited new possibilities around the globe due to its plausible health benefits and functional properties. This research aimed to evaluate the effect of processing on the resistant starch content in selected Indian rice varieties and its effect on postprandial blood glucose levels. Methods: Two Indian rice varieties (Sona Masuri and Mogra) were evaluated for resistant starch in raw form, after boiling, steaming, and refrigeration. Thereafter, the increment in resistance starch content by different processing methods was validated by oral glucose tolerance test (OGTT) on ten healthy participants. Results: Among the two rice varieties, raw Sona Masuri had a higher resistance starch content (10.86%). After processing, resistant starch was observed to be high in steamed Mogra variety (3.52%). In the boiling process, Sona Masuri developed a higher resistant starch content (2.44%) as compared to Mogra variety (1.05%). The assessment done after refrigeration revealed a slight increase in resistant starch content in both rice varieties. Mogra variety had higher resistant starch (3.68%) than the other rice variety (2.56%) after refrigeration. Validation of increase in resistant starch content and its effect on blood glucose responses done through OGTT revealed that Mogra rice (test food) did not cause a swift spike in blood glucose level compared to glucose (reference food). Differences in blood glucose responses by test and reference food at 0, 30, 60, 90, and 120 minutes were statistically significant. Conclusion: Steamed and refrigerated Mogra rice did not cause significant increase in blood glucose.

Effect of microwave followed by cooling on structural and digestive properties of pinhão starch

To increase its resistant content, native pinhão starch was modified using a microwave (300 W, 90 s) and subsequently cooled at 4 °C for 4, 8, 16, 24, and 72 h. The results demonstrated that all starches exhibited a crystalline structure of type C, with decreased crystallinity after modification. In the modified samples, the ratio of peaks 1047/1022 cm−1 and 995/1022 cm−1, as identified by FTIR, indicated a reduction in the crystalline region and damage to the double helix structure of starch granules. DSC analysis revealed that modified starches had lower gelatinization temperature range values due to the presence of more homogeneous crystals. Rheological analyses showed that starch suspensions obtained exhibited pseudoplastic fluid behavior and gel-like viscoelastic structure formation, with higher storage moduli in samples with longer cooling times. The microwave-modified starch, cooled for 72 h, exhibited higher digestion resistance, resulting in a 43.6 % increase in resistant starch content and a 26.1 % decrease in rapidly digestible starch compared to native starch. The results highlight that the modification of native pinhão starch using a microwave, followed by cooling at 4 °C for 72 h, presents a promising method for increasing the resistant starch content.

Physicochemical and Functional Properties of Banana Starch and Its Alternative Returns

The current study’s goal is to isolate the starch from different varieties of banana i.e. Local Banana (LB) and BARI Banana2 (BB2)and characterize them in order to explore their physical and chemical compositions, amylose content, resistant starch content, functional properties, granule morphology and crystalline pattern. Different techniques were used for characterization viz. X-ray diffractometery (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Spectroscopy (SEM) etc. The starch extracted from banana showed significant difference in the amylose content and the value was found 28.26%and 25.93%respectively for local banana starch (LBS) and bari banana 2 starch (BB2S). This study also revealed that selected banana varieties can be a potential source for the production of resistant starch. The resistant starch (RS) content of the banana was found 46.93% and 45.78% respectively for LBS and BB2S. Using de-branching and autoclaving technique in the starch, there was a significant increase in RS content. Paste clarity was decreased gradually with time for all the starch samples. Water absorption capacity (WAC) and oil absorption capacity (OAC) of LBS and BB2Swere found in the ranged of 165.8-170.7% and 132.6-168.1% respectively. XRD showed both LB and BB2 starches had B-type crystal pattern. The d-spacing of banana starches were ranged from 3.86-5.88Á. SEM data revealed that banana starches possessed the regular elongated round ridges with smooth surface in the range of 4.3-12.4 µm. The information obtained from this research indicates that both banana starches can be used in different areas; especially in food, pharmaceutical and cosmetics industries as an edible coating, thickening agent, fat replacer, etc. Also, banana starch containing functional food can be recommended for diabetic patients.

Evaluating the effect of different physical pretreatments and cooking methods on nutritional (starch digestibility) and physicochemical properties of white rice grains (Fajr cultivar)

The effects of physical pretreatments including steaming, dry heating and a combination thereof (performed at different times) were evaluated on the content of resistant starch (RS), slowly digestible starch (SDS), and rapidly digestible starch (RDS), morphology, crystalline structure, and some other physicochemical properties of uncooked Iranian rice grains (Fajr cultivar). The grains were then subjected to cooking by various methods (i.e., boiling, rinsing, and steam-cooking) to investigate the effect of cooking on the nutritional properties obtained after applying physical pretreatments. Generally, reaction constant (k), hydrolysis index (HI), and estimated glycemic index (eGI) decreased after pretreatments. Physical pretreatments increased R1047/1022. Pretreated and cooked grains had significantly higher RS content (5–20%) than non-treated cooked samples. Morphology and crystalline structure were affected by pretreatments. Cooking by rinsing method is suggested for patients with type 2 diabetes mellitus because of lowering the HI (30%) and eGI (18%). Steam-cooking method is recommended for preparing a dietary rice meal due to the higher RS and SDS content. Pretreatment by steaming and cooking by boiling are suitable for people suffering from chewing problems. In conclusion, applying physical pretreatments and choosing appropriate cooking method can increase RS content, decrease eGI, and hence improve nutritional characteristics of rice grains.

Creating high-resistant starch rice by simultaneous editing of SS3a and SS3b.

Creating high-resistant starch rice by simultaneous editing of SS3a and SS3b.

Effects of resistant starch on anti-obesity status and nutrient digestibility in dogs.

This study investigated the effects of corn resistant starch (RS) on the anti-obesity properties, nutrient digestibility, and blood parameters in healthy beagles. Four spayed and six castrated beagle dogs were divided into a control group (CON) with a diet comprising rice and chicken meal and a treatment group (TRT) with a diet comprising corn with an increased RS content by heating-cooling and chicken meal. All dogs in the CON and TRT groups were fed a 1.2-fold higher energy diet than the daily recommended energy requirement for 16 weeks. Throughout the study period, the body weight of dogs in CON increased, whereas no change in body weight was observed in TRT, resulting in a significant difference in body weight between the two groups at the end of the experiment. Moreover, a significant reduction in the apparent total tract digestibility was observed upon the analysis of dry matter, nitrogen-free extract, and organic matter in TRT compared with that in CON. The complete blood cell composition and biochemical parameters were within the reference range in both groups. A significant increase in the concentration of serum adiponectin was found in TRT at the end of the experiment. These results suggest that the corn RS may be beneficial for weight management owing to its reduced nutrient digestibility.

Effect of combining acid modification and heat-moisture treatment (HMT) on resistant starch content: A systematic review

&lt;abstract&gt; &lt;p&gt;Type 2 diabetes mellitus (DMT2) is a metabolic disease that is increasingly attracting public attention. Diabetes mellitus is expected to reach 439 million in the world in 2030. Resistant starch (RS) is an indigestible starch which has health properties which has health properties that can be used for preventing diabetes mellitus type 2. In order to increase the RS content, a dual modification method consisted of acidification and heat moisture treatment (HMT) can be applied. The Acid-HMT method is affected by various factors, i.e., acid types, acid concentration, water content ratio, HMT temperature and HMT processing time, and different treatments may result in different RS yields. This study aimed to analyze the effective treatment in the Acid-HMT dual modification to enhance RS content by using a systematic review based on the PRISMA method. The studies revealed that there were 11 articles (n = 68 data) which utilized various acid types combined with HMT. The utilization of acid-alcohol, HCl, and organic acid such as citric acid, acetic acid, and lactic acid resulted in different results of RS content in modified starch. In addition to acid types, treatment conditions such as acid concentration, acidification time, acidification temperature, water content ratio, HMT time, and HMT temperature also affected the resulted RS. The treatment with 0.2 M citric acid for 24 hours at 25 ℃ combined with HMT with 30% moisture at 110 ℃ for 8 hours resulted in the highest increase in RS content of modified starch.&lt;/p&gt; &lt;/abstract&gt;

Biofabrication, structure, and functional characteristics of a reuteran-like glucan with low digestibility

A novel reuteran-like glucan with low digestibility was fabricated using microbial glucanotransferase (GTase) treated maltodextrin. For GTase treated maltodextrin with DE 6, the molecular weight of reuteran-like glucan increased from 8.35 × 104 to 5.14 × 106 g/mol in the initial 6 h, increasing to 1.47 × 107 g/mol at 72 h. The short chain fraction (DP 3–12) of reuteran-like glucan increased from 45.2 % to 100.0 %, accompanied by an increase in α-1,6 glycosidic linkage percentage from 3.9 % to 33.3 %. This reaction promoted rearrangements in glycosidic chains, leading to a substantial increase in resistant starch content (13.4 % to 37.4 %) in the reuteran-like glucan. During in vitro fecal fermentation for 48 h, the reuteran-like glucan yielded large amounts of short-chain fatty acids (212.33 mM), especially butyric acid (12.64 mM). Thus, reuteran-like glucan could be used as a low-digestible and highly fermentable fiber for controlling blood glucose levels and prebiotic potential.

Effect of annealing treatment on the physicochemical properties and enzymatic hydrolysis of different types of starch

Annealing treatment on the physicochemical properties and hydrolysis of maize, potato and pea starch were investigated in present study. Results indicated that annealing treatment did not change the morphology of the starch. However, the relative crystallinity of maize and potato starch showed a peak trend as the annealing time extended, while pea starch showed a lower relative crystallinity. Besides, all the annealed starch showed a decrease in peak viscosity and an increase in pasting time. Little difference in the rapidly digestive starch (RDS) and resistant starch (RS) contents of annealed maize starch and pea starch were observed after annealing, while annealed potato starch (72 h) showed an increased RS content (23.37 ± 5.36 %) and a decreased RDS content (52.60 ± 6.14 %), respectively. The obtained results may provide a better understanding of the physicochemical properties and enzymatic hydrolysis of annealed starch with different semi crystalline type.

Influence of plasma-activated water on the morphological, functional, and digestibility characteristics of hydrothermally modified non-conventional talipot starch

The starch isolated by the alkali method from talipot palm ( Corypha umbraculifera L . ) stem pith is a non-conventional starch with a high yield (76%). Talipot starch was subjected to hydrothermal treatments, heat-moisture treatment (HMT) and annealing (ANN) with plasma-activated water (PAW). HMT and ANN with PAW created fissures and surface degradation and significantly increased (p ≤ 0.05) the relative crystallinity of talipot starch from 16.91% to 26.96%. The increased crystalline perfection of modified starch significantly decreased (p ≤ 0.05) the swelling power and increased the pasting temperature, gelatinization temperature, and gelatinization enthalpy. The significant decrease (p ≤ 0.05) in peak and breakdown viscosities and enhancement in storage and loss moduli indicates improved shear and thermal stability of modified starch gels. PAW with acidic nature decreased the starch digestibility and increased the resistant starch content to 51.03% and 52.11% after HMT and ANN treatments, respectively. The reactive species present in the PAW reduced the retrogradation tendency by reducing the setback and final viscosities and improving the paste clarity of modified starches. PAW modified starch gel possessing enhanced paste clarity is suitable for the preparation of pie fillings, soups and sauces. Hydrothermal treatments with PAW can be regarded as a novel technique to modify starch without enzymes, acids, or cross-linking agents to improve the functionality, reduce retrogradation tendency and increase resistant starch content. • Heat-moisture treatment (HMT) and annealing (ANN) were done on talipot starch. • HMT and ANN with plasma-activated water (PAW) increased starch crystallinity. • Hydrothermal treatment with PAW enhanced the thermal stability of talipot starch. • HMT and ANN with PAW showed reduced retrogradation tendency in talipot starch. • Hydrothermal treatment with PAW increased the resistant starch content.

Carbohydrate Repartitioning in the Rice Starch Branching Enzyme IIb Mutant Stimulates Higher Resistant Starch Content and Lower Seed Weight Revealed by Multiomics Analysis.

The starch branching enzyme IIb mutant (be2b) in rice significantly increases the resistant starch (RS) content and leads to reduced seed weight. However, the underlying metabolic mechanisms remain unclear. Proteomic analysis indicated that upregulation of starch synthase IIa (SSIIa) and SSIIIa and downregulation of BEI and SSI were possibly responsible for the decreased short amylopectin chains (DP 6-15) and increased longer chains (DP > 16) of be2b starch. The upregulation of granule-bound starch synthase led to increased amylose content (AC). These changes in the amylopectin structure and AC accounted for the increased RS content. α-Amylase 2A showed the strongest upregulation (up to 8.45-fold), indicating that the loss of BEIIb activity enhanced starch degradation. Upregulation of glycolysis-related proteins stimulated carbohydrate repartitioning through glycerate-3-phosphate and promoted the accumulation of tricarboxylic acid cycle intermediates, amino acids, and fatty acids. The unexpected carbohydrate partitioning and enhanced starch degradation resulted in the reduced seed weight in the be2b mutant.

Optimization of Corn Resistant Starch Preparation by Dual Enzymatic Modification Using Response Surface Methodology and Its Physicochemical Characterization.

Corn starch was dually modified using thermostable α-amylase and pullulanase to prepare resistant starch (RS). The concentration of starch liquid, the amount of added thermostable α-amylase, the duration of enzymatic hydrolysis and the amount of added pullulanase were optimized using RSM to increase RS content of the treated sample. The optimum pretreatment conditions were 15% starch liquid, 3 U/g thermostable α-amylase, 35 min of enzymatic hydrolysis and 8 U/g pullulanase. The maximum RS content of 10.75% was obtained, and this value was significantly higher than that of native corn starch. The degree of polymerization (DP) of the enzyme-modified starch decreased compared with that of native starch. The scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were performed to assess structural changes in native and pretreated starch. The effect of dual enzyme pretreatment on the structure and properties of corn starch was significant. Unlike the untreated one, the pretreated corn starch showed clear pores and cracks. Significant differences in RS contents and structural characterization between starch pretreated and untreated with dual enzymes demonstrated that the dual enzyme modification of corn was effective in enhancing RS contents.

Increasing the level of resistant starch in 'Presidio' rice through multiplex CRISPR-Cas9 gene editing of starch branching enzyme genes.

Rice (Oryza sativa L.) is an excellent source of starch, which is composed of amylopectin and amylose. Resistant starch (RS) is a starch product that is not easily digestible and absorbed in the stomach or small intestine and instead is passed on directly to the large intestine. Cereals high in RS may be beneficial to improve human health and reduce the risk of diet-related chronic diseases. It has been reported through chemical mutagenesis and RNA interference studies that starch branching enzymes (SBEs) play a major role in contributing to higher levels of RS in cereal crops. In this study, we used multiplex clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR associated protein 9 (Cas9) genome editing to simultaneously target all four SBE genes in rice using the endogenous transfer RNA (tRNA)-processing system for expressing the single-guide RNAs (sgRNAs) targeting these genes. The CRISPR-Cas9 vector construct with four SBE gene sgRNAs was transformed into the U.S. rice cultivar Presidio using Agrobacterium-mediated transformation. Knockout mutations were identified at all four SBE genes across eight transgene-positive T0 plants. Transgene-free T1 lines with different combinations of disrupted SBE genes were identified, with several SBE-edited lines showing significantly increased RS content up to 15% higher than the wild-type (WT) cultivar Presidio. Although further efforts are needed to fix all of the mutant alleles as homozygous, our study demonstrated the potential of multiplex genome editing to develop high-RS lines.

Enhancement of enzymatic resistance in V-type starch inclusion complexes by hydrothermal treatments

Resistant starch (RS) is well known for its health beneficial effects for glycemic control and gut health. In addition to some commonly reported RS types, such as raw high amylose maize starch (HAMS), potato starch, retrograded starch, and cross-linked starch, formation of starch inclusion complexes could also contribute to an increase in RS content. In this study, V type starch inclusion complexes with two guest compounds, ascorbyl palmitate (AP) and palmitic acid (PA), were formed using the novel “empty” V type method, and hydrothermal treatments were performed to further enhance the RS contents. Complimentary X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques were conducted to assess the crystalline structure and thermal properties of the raw and treated inclusion complexes, and simulated in vitro enzymatic digestion was performed to study the structure-digestibility relationship in the treated samples. Although the raw inclusion complex samples exhibited minimal RS contents, all the treatments retarded starch digestion by increasing RS or SDS levels. For both V6h-AP and V6h-PA inclusion complexes, annealing followed by long-term strong acid hydrolysis treatment (ANN-ACH) resulted in the greatest increase in RS content, followed by strong ACH treatments alone. In addition, while presenting a comparable RS level as traditional RS2, the ANN-ACH treated V6h-AP inclusion complex retained a V type crystalline structure, indicating its great potential as a novel type of RS, i.e., RS5. The study findings could have practical implications for the design and modification of RS-containing food for the control and modulation of glycemic response.