Dietary Resistant Starch Research Articles

231 Impact of Brachyspira hyodysentariae on intestinal function and integrity

Abstract Swine dysentery (SD) induced by Brachyspira hyodysentariae (Bhyo) causes colitis and mucohemorrhagic diarrhea in grow-finish pigs, however little is known about the physiological changes that occur to the gastrointestinal tract during Bhyo infection. Thus, the objective of this study was to evaluate the impact of a Bhyo challenge on intestinal function and integrity of pigs fed two divergent diets. A total of 36 Bhyo negative gilts (24.3 ± 3.6 kg BW) were selected and assigned to one of three treatment groups (n=12 pigs/trt): 1) Bhyo negative, 20% DDGS diet (CON), 2) Bhyo challenged, 20% DDGS diet (DDGS), and 3) Bhyo challenged, 10% DDGS, 5% beet pulp and 5% resistant potato starch diet (RS). Pigs were fed diets 21 days prior to challenge and on days post inoculation (dpi) 0 and 1, pigs were inoculated with Bhyo or sham. Fecal samples were collected for ATTD and pigs were euthanized for colon collection within 72 hours of initial observation of clinical SD, or at the end of the study (dpi 10-16). Tissues were assessed for ex vivo measures of intestinal integrity and mitochondrial function. The challenge resulted in high morbidity, with 88% of DDGS and RS pigs developing clinical SD. Colon transepithelial resistance was increased in DDGS pigs compared with CON and RS pigs (P=0.005), and colon macromolecule permeability was reduced in both DDGS and RS pigs compared with CON pigs (P=0.006), likely due to mucoid discharge. Colonic mitochondrial oxygen consumption was not impacted by treatment (P >0.10). Further, ATTD of DM, OM, N, and GE were reduced in DDGS pigs compared with CON pigs (P< 0.001), whilst nutrient digestibility was not reduced in RS pigs. Taken together, these data show Bhyo does not appear to reduce ex vivo colonic integrity. Further, the RS diet may reduce severity of a Bhyo challenge.

Dietary resistant starch preserved through mild extrusion of grain alters fecal microbiome metabolism of dietary macronutrients while increasing immunoglobulin A in the cat.

Dietary digestion-resistant starch (RS) provides health benefits to the host via gut microbiome-mediated metabolism. The degree to which cats manifest beneficial changes in response to RS intake was examined. Healthy cats (N = 36) were fed identically formulated foods processed under high (n = 17) or low (n = 19) shear extrusion conditions (low and high RS levels [LRS and HRS], respectively). Fecal samples collected after 3 and 6 weeks' feeding were assayed for stool firmness score, short-chain fatty acids, ammonia, and changes to the global metabolome and microbiome; fecal immunoglobulin A (IgA) was analyzed at week 6. Few differences were seen in proximate analyses of the foods; stool firmness scores did not differ. In cats consuming HRS food, concentrations of fecal butyrate and the straight chain:branched chain fatty acid ratio were significantly greater in feces at both weeks 3 and 6, while fecal ammonia was reduced at week 6 relative to feces from LRS-fed cats. Fecal IgA concentrations were significantly higher at week 6 with HRS food. RS consumption altered 47% of the fecal metabolome; RS-derived sugars and metabolites associated with greater gut health, including indoles and polyamines, increased in the cats consuming HRS food relative to those fed the LS food, while endocannabinoid N-acylethanolamines decreased. Consumption of HRS food increased concentrations of the ketone body 3-hydroxybutyrate in feces and elevated concentrations of reduced members of NADH-coupled redox congeners and NADH precursors. At the microbiome genus-level, 21% of operational taxonomic units were significantly different between food types; many involved taxa with known saccharolytic or proteolytic proclivities. Microbiome taxa richness and Shannon and Simpson alpha diversity were significantly higher in the HRS group at both weeks. These data show that feline consumption of grain-derived RS produces potentially beneficial shifts in microbiota-mediated metabolism and increases IgA production.

Evaluation of the Effects of a Resistant Starch Diet and Metaproteomics Study of Microbiome-Host Interactions in a 5/6 Nephrectomy Murine Model of CKD

Evaluation of the Effects of a Resistant Starch Diet and Metaproteomics Study of Microbiome-Host Interactions in a 5/6 Nephrectomy Murine Model of CKD

Usual Dietary Intake of Resistant Starch in US Adults from NHANES 2015–2016

Resistant starch (RS) confers many health benefits, mostly due to nonenzymatic human digestion and gut microbiota fermentation capacity. The usual intake of naturally occurring dietary RS in US adults is unclear. This study estimated usual daily RS intake in grams per 1000kcal in US adults by sex, age, and ethnic group, as well as the most frequent food category contributing to RS intake using data from the NHANES 2015-2016. RS content of foods consumed was matched with Food and Nutrient Database for Dietary Studies food codes. The National Cancer Institute method was used to estimate adults' usual RS intake from 2 24-h dietary recalls. Day 1 RS contribution from food groups to overall RS intake was ranked for the total sample, across age-sex categories, and across ethnic groups. In total, 5139US adults (48.4% male) had a mean daily usual intake of RS of 1.9±0.0g/(1000kcal⋅d).Males and females had a similar intake of RS [2.0±0.0g compared with 1.9±0.0g/(1000kcal⋅d)] with no differences between sexes within the same age category. When comparing ethnic groups within each age category, the non-Hispanic white males and females had significantly lower RS intake than all other ethnic groups [range: 1.7-1.8 compared with 2.1-2.3g RS/(1000kcal⋅d), respectively], with no differences among the other ethnic groups. French fries and other fried white potatoes, rice, and beans, peas, and legumes were the most frequently consumed food categories contributing to RS intake in all adults. US adults should improve the intake of natural RS food sources. Increasing RS intake will improve gastrointestinal health as a prebiotic and potentially increase insulin sensitivity with adequate consumption (e.g., ∼15g/d).

Effects of dietary resistant potato starch inclusion and stocking density on growth performance, feather condition, and skin inflammatory cytokine gene expression in Pekin ducks

This study investigated whether dietary resistant potato starch (RPS) inclusion alleviated the stress response of high stocking density (HSD) based on growth performance, carcass traits, immune organ index, serum corticosterone concentration, and skin inflammatory cytokine gene expression in meat ducks. A total of 576 1-d-old male ducklings were assigned to 4 groups of 8 replicates and were under the following conditions: normal stocking density (NSD; 16 birds/m2(d 1−14); 8 birds/m2(d 15−35)) and HSD (32 birds/m2(d 1−14); 16 birds/m2(d 15−35)). The ducks were fed the basal diet or the basal diet supplemented with 12 % RPS for 35d reared under HSD and NSD to form a 2 × 2 factorial experimental design. The results showed that HSD significantly depressed (P < 0.05) the growth performance, breast meat yield, feather and spleen development, and increased (P < 0.05) the pH value in proventriculus, serum corticosterone as well as mRNA abundance of interleukin (IL)-1β and IL-6 in the skin of the pelvic back in meat ducks compared to NSD. However, dietary RPS inclusion only markedly increased (P < 0.05) BW (d 14) and BWG (d 1−14), breast meat yield, and percentage of spleen in body weight (d 35) of ducks reared under NSD. Regardless of stocking density, dietary RPS inclusion significantly increased (P < 0.05) bursa of Fabricius and spleen percentages in BW and decreased (P < 0.05) feather scoring of 35-day-old ducks in comparison with no RPS inclusion. These results suggested that HSD had a negative effect on growth and feather performance, as well as meat deposition and even caused skin inflammation of meat ducks; however, RPS supplementation did not alleviate these negative effects caused by HSD.

Glucose and lipid metabolism of broiler chickens fed diets with graded levels of corn resistant starch

ABSTRACT 1. The aim of this study was to investigate the effects of graded levels of dietary corn resistant starch (RS) on glucose and lipid metabolism of broilers. 2. A total of 320 male broiler chicks (Arbor Acres, one-day-old) were randomly allocated to five dietary treatments, including a corn-soybean control diet, a corn-soybean based diet containing 20% corn starch, and three diets containing 4%, 8% and 12% RS by replacing corn starch with 6.67%, 13.33% and 20% Hi-Maize® 260 (identified as control, RS1, RS2, RS3 and RS4, respectively). Each treatment contained eight replicates with eight birds, and the experiment lasted 42 days. 3. Birds fed RS diets showed lower (P < 0.05) concentrations of serum low-density lipoprotein cholesterol and non-esterified fatty acid (NEFA) at d 21 and 42 of age, compared to the control. Lower (P < 0.05) hepatic apolipoprotein B concentration and citrate synthase (CS) activity, as well as a higher (P < 0.05) glycogen synthase (GS) concentration were observed in birds fed RS diets than those in the control group at d 21 of age. Consuming RS diets linearly increased (P < 0.01) serum glucose concentration, and linearly decreased (P < 0.01) NEFA concentrations in broilers at d 21 and 42 of age. Liver GS concentration and activities of hexokinase, pyruvate and CS were linearly increased (P < 0.01) in broilers at d 21 of age, but were linearly decreased (P < 0.05) in birds at d 42 of age in response to the increase of dietary RS levels. Feeding RS diets linearly decreased (P < 0.05) mRNA expressions of PC, PPARα and CPT-1 at d 21 of age and the mRNA expressions of SREBP-1 c, ChREBP, ACC and FAS at d 42 of age, and linearly increased (P < 0.05) the mRNA expressions of PEPCK, PC, LKB1, AMPKα1, PPARα, CPT-1 and L-FABP at d 42 of age. 4. Feeding broilers with diets containing higher concentration of RS promoted hepatic lipolysis and gluconeogenesis through activated AMPK signalling pathway and accelerated whole-body energy expenditures in the grower phase.

Maternal dietary resistant starch does not improve piglet\u2019s gut and liver metabolism when challenged with a high fat diet

BackgroundIn the past several years, the use of resistant starch (RS) as prebiotic has extensively been studied in pigs, and this mostly in the critical period around weaning. RS is believed to exert beneficial effects on the gastrointestinal tract mainly due to higher levels of short chain fatty acids (SCFAs) and an improved microbiota profile. In this study, sows were fed digestible starch (DS) or RS during late gestation and lactation and the possible maternal effect of RS on the overall health of the progeny was assessed. Since RS is also described to have a positive effect on metabolism, and to investigate a metabolic programming of the progeny, half of the piglets per maternal diet were assigned to a high fat diet from weaning on to 10 weeks after.ResultsNo bodyweight differences were found between the four experimental piglet groups. The high fat diet did however impact back fat thickness and meat percentage whereas maternal diet did not influence these parameters. The impact of the high fat diet was also reflected in higher levels of serum cholesterol. No major differences in microbiota could be distinguished, although higher levels of SCFA were seen in the colon of piglets born from RS fed sows, and some differences in SCFA production were observed in the caecum, mainly due to piglet diet. RNA-sequencing on liver and colon scrapings revealed minor differences between the maternal diet groups. Merely a handful of genes was differentially expressed between piglets from DS and RS sows, and network analysis showed only one significant cluster of genes in the liver due to the maternal diet that did not point to meaningful biological pathways. However, the high fat diet resulted in liver gene clusters that were significantly correlated with piglet diet, of which one is annotated for lipid metabolic processes. These clusters were not correlated with maternal diet.ConclusionsThere is only a minor impact of maternal dietary RS on the progeny, reflected in SCFA changes. A high fat diet given to the progeny directly evokes metabolic changes in the liver, without any maternal programming by a RS diet.

Abundance of the species Clostridium butyricum in the gut microbiota contributes to differences in obesity phenotype in outbred Sprague-Dawley CD rats.

Gut microbiota profiles contribute to differences in obesity phenotype. We examined the abundance of the species Clostridium butyricum in relation to obesity phenotype. In outbred Sprague -Dawley rats we examined effects of dietary fat, resistant starch (RS), and a microbiota transplant on obesity phenotype. Using targeted qPCR, we examined the abundance of total gut bacteria and C. butyricum in relation to the propensity of obesity prone and obesity resistant rats to accumulate abdominal fat. Before inclusion of dietary RS, obesity resistant (OR) rats had higher amounts of total bacteria, and C. butyricum compared to obesity prone (OP) rats (P < 0.005 in study I, P < 0.0001 in study II). A high fat diet (HF) lowered C. butyricum levels while RS had no effect. Dietary RS elicited robust fermentation and increased total bacteria only in OP rats. In preparation for the transplant, antibiotics were administered to recipient rats. Four weeks thereafter, total bacteria levels were restored but, C. butyricum levels were not. The transplant between the two phenotypes had no effect on abundance of C. butyricum and obesity phenotype. While C. butyricum is a known saccharolytic, its proliferation is not enhanced by fermentation of resistant starch. C. butyricum maybe one of the species that constitute a core microbiota involved in energy storage and metabolism through mechanisms that are not yet known.

Fermentation of Resistant Starch Is Not a Predictor of Very High or Low Serum TMAO in Rats, but Results in Greater Serum TMAO than Controls

Abstract Objectives Consumption of resistant starch (RS) has positive gut health benefits, but RS has been associated with increased serum trimethylamine oxide (TMAO). Increased serum TMAO has been linked to enhanced risk of cardiovascular death. A human study found that RS and a high fat (41% of energy) diet resulted in higher TMAO levels compared to a low RS diet, but this was not seen in a high carbohydrate diet (27% energy as fat). We wanted to ascertain serum TMAO in rats fed a high-RS diet with moderate (MF) or high fat (HF) diets compared to controls. Methods Twenty-four male, Sprague-Dawley rats (n = 6) were fed either 23% RS type 2, high-amylose diet or a control diet using 100% amylopectin with either MF (30% energy) or HF (42% energy) levels. A 2X choline amount had been used in the AIN-93M diets as substrate for ultimate production of TMAO. After six weeks, serum TMAO was measured using stable isotope dilution liquid chromatography tandem mass spectrometry. Data were analyzed as a 2 × 2 factorial followed by Tukey test (P &amp;lt; 0.05). Serum TMAO is assessed for risk of death over a seven-year period into quadrants. Quadrants 3 (4.28–7.89 µM) and 4 (7.91-186.1 µM) have greater risk. Quadrants 1 (0.12–2.55 µM) and 2 (2.56–4.27 µM) had much lower risk. Results Average TMAO level for rats fed RS HF was 2.94 ± 0.4, and RS MF was 2.42 ± 0.4. The control HF was 1.53 ± 0.17, and control MF was 1.06 ± 0.17. Rats fed RS had significantly greater TMAO levels of 2.68 ± 0.28, quadrant 2, while the control rats had an average of 1.3 ± 0.12, quadrant 1. There was no significant increased effect for MF vs. HF. However, the variability was similar for the two RS groups with values in quadrants 1–3. Amount of fermentation was not associated with TMAO amounts. For example, the RS rat with the lowest serum TMAO (0.87 µM) had an empty cecum weight (ECW) of 2.40 g, while the highest (4.41 µM) had an ECW of 2.29 g. Conclusions Sprague-Dawley rats fed either MF or HF had increased TMAO with consumption of RS. Data indicate amount of fermentation is not the reason for increased TMAO. Possible differences in gut bacteria that produce trimethylamine from choline may be cause of TMAO production in the rats. Funding Sources LSU AgCenter and Lerner Research Institute (Dr Stan Hazen) of Cleveland Clinic for analysis of serum TMAO, and starches were gifted from Ingredion Incorporated.

Efek Pati Resisten Singkong (Manihot esculenta Crantz) terhadap Indeks HOMA-IR dan HOMA-B Tikus Model Diabetes

Insulin resistance is a condition in which target organs fail to respond normally to insulin. Cassava contains 9,69 percent starch that resist to digestive enzyme in intestine and has been shown to increase insulin sensitivity and enhance β cell function. The aim of this study was to analyze the difference effect of native cassava starch and cassava resistant starch consumption on insulin resistance and β cell function indexes. This study was quasy experimental research with post-test only control group design using 16 male wistar strain rats divided into four groups: K1 (normal rats with standard diet), K2 (diabetic rats with standard diet), P1 (diabetic rats with native cassava starch diet) and P2 (diabetic rats with cassava resistant starch diet). The rats were fed with high fat diet and injected with low-dose streptozotocin to mimic the patogenesis of type 2 diabetes. The rats were then fed with assigned diet for 28 days. The data collection was obtained from laboratory examination of fasting plasma glucose and fasting plasma insulin to determine HOMA-IR and HOMA-B indexes. Post Hoc analysis showed no difference in both indexes between native cassava starch and cassava resistant starch fed groups (p&gt;0,05).

Dietary corn resistant starch regulates intestinal morphology and barrier functions by activating the Notch signaling pathway of broilers.

ObjectiveThis study was conducted to investigate the effects of dietary corn resistant starch (RS) on the intestinal morphology and barrier functions of broilers.MethodsA total of 320 one-day-old broilers were randomly allocated to 5 dietary treatments: one normal corn–soybean (NC) diet, one corn–soybean–based diet supplementation with 20% corn starch (CS), and 3 corn–soybean–based diets supplementation with 4%, 8%, and 12% corn resistant starch (RS) (identified as 4% RS, 8% RS, and 12% RS, respectively). Each group had eight replicates with eight broilers per replicate. After 21 days feeding, one bird with a body weight (BW) close to the average BW of their replicate was selected and slaughtered. The samples of duodenum, jejunum, ileum, caecum digesta, and blood were collected.ResultsBirds fed 4% RS, 8% RS and 12% RS diets showed lower feed intake, BW gain, jejunal villus height (VH), duodenal crypt depth (CD), jejunal VH/CD ratio, duodenal goblet cell density as well as mucin1 mRNA expressions compared to the NC group, but showed higher concentrations of cecal acetic acid and butyric acid, percentage of jejunal proliferating cell nuclear antigen-positive cells and delta like canonical Notch ligand 4 (Dll4), and hes family bHLH transcription factor 1 mRNA expressions. However, there were no differences on the plasma diamine oxidase activity and D-lactic acid concentration among all groups.ConclusionThese findings suggested that RS could suppress intestinal morphology and barrier functions by activating Notch pathway and inhibiting the development of goblet cells, resulting in decreased mucins and tight junction mRNA expression.

P139 EFFECT OF LYSOSOMAL SHORT CHAIN FATTY ACID DELIVERY ON IMMUNE RESPONSE

Abstract Short chain fatty acids (SCFAs) are known as metabolites produced from gut microbiome fermenting dietary fibers and resistant starch. They are regulators of the interplay between the microbiome and its host and may have a role in the pathogenesis of inflammatory bowel disease (IBD). Free SCFAs influence intestinal epithelial and immune cells (e.g. macrophages and primary monocytes) through activation of free fatty acid receptors FFAR2 and FFAR3, inhibition of histone deacetylases (HDAC) and as a source of energy. SCFAs are known to impact cytokine production and differentiation of immune cells (e.g. Tumor necrosis factor alpha (TNFa), Interleukin (IL)-10, IL-6, IL-18, IL-1ß). We investigated the role of SCFAs in dextran sulfate sodium-induced colitis and their effect on the cytokine production by primary human immune cells. Treatment with SCFAs (acetate, propionate or butyrate) stimulated release of IL-1ß and IL-18 by buffy coat leukocytes or U937 cells without causing increased expression of corresponding genes. This raises the possibility of activation via the NLRP3 (NOD-, LRR- and pyrin domain- containing protein 3) inflammasome. NLRP3 is a multimeric inflammasome complex. Once activated, NLRP3 inflammasome releases caspase 1 leading to formation of mature IL-1ß and IL-18. Recent studies have shown that IL-1ß promotes phagocytosis and clearance of bacteria and aids the gut in eliciting an effective response in early stages of IBD. We asked whether this effect is mediated via surface or lysosomal (phagosomal) receptors? To answer this question, we prepared a series (SYD010) of novel compounds which are able to accumulate in the phagolysosome of immune cells through their macrolide backbone and deliver SCFAs, bound as esters to the lumen of the activated lysosome. In vitro, together with LPS stimulation, the substances modulated secretion of TNFa, IL-1ß, IL-10 and IL-6 at concentrations about 100x lower than free SCFAs (Figure 1). When tested in a DSS colitis mouse model, the SYD010 series caused a decrease in diarrhea scoring compared to the vehicle-treated control group at a concentration of 0.1 mg/kg (Figure 2) which corresponds to a total dose of ca. 100 nmol/kg (the compounds are systemically distributed). This is lower than the known luminal concentrations of SCFAs which is in the range of 40 mM. Our underlying hypothesis is that lysosomal reception of SCFAs leads to beneficial immune modulation in colitis in so far as stimulation of IL-1ß release promotes bacterial clearance. Furthermore, that concentrative uptake to the phagolysosome leads to enhanced stimulation of these receptors leading to responses at lower ambient concentrations or doses. We are assessing this substance class as potential IBD therapeutics. Figure 1. Effect of sodium butyrate or CSY4286 (lysosomal butyrate donor) on cytokine production by U937 cells. Supernatants were harvested after 24 h (IL-6) and 48 h (IL-1ß, IL-6) incubation with the test substances and cytokines determined by ELISA. The dotted line represents levels with LPS stimulation alone. SEM was applied for error bars. Figure 2. Results from DSS-induced (2.5% in drinking water) IBD study in BALB/c mice (8 mice per group). Scoring of body weight and diarrhea score over 8 days (a and b show data from final day of study). SEM was applied for error bars.

Effects of Dietary Fiber Sources during Gestation on Stress Status, Abnormal Behaviors and Reproductive Performance of Sows.

Simple SummaryThis study aimed to appraise the effects of two available unconventional dietary fiber resources (resistant starch and fermented soybean fiber) on sows’ reproductive performance through an in vitro-in vivo method to facilitate their application in the rural livestock production systems. Results indicated that inclusion of 5% resistant starch with greater swelling capacity in the gestation diet was beneficial to enhancing postprandial satiety, alleviating stress status, reducing abnormal behaviors and thus lowering the stillbirth rate of sows.Inclusion of fiber in gestation diets is a method for enhancing satiety and reducing abnormal behaviors in restricted feeding sows without providing excess energy. The purpose of this study was to use an in vitro-in vivo method to appraise the effects of two available unconventional dietary fiber resources during gestation on sows’ physio-chemical properties of diets, postprandial satiety, performance, abnormal behaviors, stress status and lactation feed intake under three different dietary treatments: control diet (CON diet), 5% resistant starch diet (RS diet), and 5% fermented soybean fiber diet (FSF diet) with a total of 78 (average parity 5) Landrace × Yorkshire sows. Results showed that swelling capacity was higher in the RS diet than in the CON or FSF diet. Meanwhile, the 48 h cumulative gas production and the final asymptotic gas volume after in vitro fermentation of gestation diets showed an increased trend (p = 0.07, p = 0.09, respectively) in the RS diet versus the CON or FSF diets. While the sows’ litter size, body weight, backfat or weaning-to-estrus interval were not affected (p > 0.05) by the three treatments during gestation, the RS group showed a decline in stillbirth number (p < 0.05) and stillbirth rate (p < 0.01) relative to the other two groups. Meanwhile, the proportion of standing was lower while the sow’s serum concentrations of PYY (peptide YY) and GLP-1 (glucagon-like peptide-1) were higher (p < 0.05) on day 70 of gestation in the RS group than in the CON or FSF group. Compared with the CON group, the RS group showed a downward tendency (p = 0.07) in the sows’ plasma cortisol concentration on day 70 of gestation. A comparison of oxidative and antioxidative indicators revealed an increase in the sows’ serum FRAP (ferric ion reducing antioxidant power) (p < 0.05) and a decrease of protein carbonyl (p < 0.05) on day 109 of gestation in the RS or FSF group versus the CON group. Overall, inclusion of 5% RS with greater swelling capacity in the gestation diet contributed to enhancing the postprandial satiety, alleviating the stress status, reducing the abnormal behaviors and thus lowering the stillbirth rate of sows.

Feed intake patterns nor growth rates of pigs are affected by dietary resistant starch, despite marked differences in digestion

Current feed evaluation systems often assume that fermented starch (i.e. resistant starch (RS)) yields less energy than digested starch. However, growth rates of pigs fed low and high RS diets are often the same when feed is available ad libitum. This may be explained by its effect on digestive processes changing feeding behavior, and consequently energy utilization. This study aims to investigate the effect of RS on nutrient digestion and digesta passage rate in pigs, in combination with its effect on feeding behavior and growth performance under ad libitum conditions. In experiment 1, 20 male pigs (40 ± 2.82 kg) were fed diets containing either 50% waxy maize starch (low in RS (LRS)) or high-amylose maize starch (high in RS (HRS)), and soluble and insoluble indigestible markers. After 14 days of adaptation to the diets, pigs were fed hourly to reach steady state (6 h), dissected, and digesta were collected from eight segments. From the collected samples, nutrient digestion and passage rate of the solid and liquid digesta fraction were determined. In experiment 2, 288 pigs (80 ± 0.48 kg; sex ratio per pen 1 : 1; boar : gilt) were housed in groups of 6. Pigs were ad libitum-fed one of the experimental diets, and slaughtered at approximately 115 kg. Feed intake, growth and carcass parameters were measured. Ileal starch digestibility was greater for LRS-fed than for HRS-fed pigs (98.0% v. 74.0%; P < 0.001), where the additional undigested starch in HRS-fed pigs was fermented in the large intestine. No effects of RS on digesta passage rate of the solid or liquid digesta fraction and on feeding behavior were observed. Growth rate and feed intake did not differ between diets, whereas feed efficiency of HRS-fed pigs was 1%-unit higher than that of LRS-fed pigs (P = 0.041). The efficiency of feed used for carcass gain did not differ between diets indicating that the difference in feed efficiency was determined by the non-carcass fraction. Despite a 30% greater RS intake (of total starch) with HRS than with LRS, carcass gain and feed efficiency used for carcass gain were unaffected. RS did not affect digesta passage rate nor feeding behavior suggesting that the difference in energy intake between fermented and digested starch is compensated for post-absorptively. Our results indicate that the net energy value of fermented starch currently used in pig feed evaluation systems is underestimated and should be reconsidered.

Comparison of chemical properties, glycemic index, and glycemic load, between arrowroot (Maranta arundinaceae) cookies containing glucomannan extract with palm sugar addition

Diabetes Mellitus (DM) is a degenerative disease mainly caused by high carbohydrate and high glycemic index (GI) diet. Meanwhile, Indonesia has large source of low GI food, such as arrowroot, porang tuber, and palm sugar that has not developed well. Cookie, as a well-known snack in Indonesia, will be made from the combination of arrowroot flour, porang glucomannan extract, and palm sugar is expected could be an alternative snack for diabetic people. The aim of research is to investigate the difference of chemical properties (proximate, total starch, total dietary fiber, total sugar, and resistant starch), GI, and glycemic load (GL) between arrowroot cookies containing glucomannan extract with palm sugar and cane sugar addition. The research was conducted using analytical observation method with cross-sectional design. Chemical properties will be compared using unpaired t-test. GI of cookies with palm sugar is 19.6, while GI of cookies with cane sugar is 25.6. GL of cookies with palm sugar is 13.71, while GL of cookies with cane sugar is 17.6. There is no significant difference in chemical properties, except in total dietary fiber (p&lt;0.05). Both cookies classified into low GI and moderate GL food.

Dietary resistant starch modifies the composition and function of caecal microbiota of broilers.

Diet plays an important role in shaping the composition of gut microbiota. Starch is the main source of carbohydrates in diets of broilers. This study investigated the effects of dietary corn starch and resistant starch on composition and function of caecal microbiota of broilers. A total of 320, 1-day-old male Arbor Acres broiler chicks were randomly assigned into five groups including normal corn-soybean (NC) diet, corn starch (CS) diet group, 4%, 8% and 12% resistant starch (RS) diet groups. The caecal contents of 42-day old broilers were sampled and microbiota community was analysed with 16S rRNA gene sequences. The CS group increased the abundances of Bilophila, Eggerthella, Olsenella and Sellimonas and decreased proportion of Akkermansia, Eisenbergiella, Oscillospira, Ruminococcaceae NK4A214 group and Synergistes in the caecum of birds compared to the NC group. However, the birds from RS groups had higher abundances of Anaerofilum, Bacteroides, Desulfovibrio and Parasutterella and lower abundances of Alistipes, Bilophila, Christensenellaceae R-7 group, Eggerthella and Ruminiclostridium 1 than the CS group. Functional prediction of these changes in microbiota revealed that the CS diet drove caecal microbiota that were more inclined to utilize carbohydrates through glycolysis/gluconeogenesis metabolism, while the 8%RS and 12%RS diets depleted microbial glycolysis/gluconeogenesis and amino acids metabolism. Dietary CS and RS alter the microbial composition and diversity, and modulate the metabolic pathways of microbial metabolism in caecum of broilers, which may further affect nutrient utilization and hindgut health of the host. © 2019 Society of Chemical Industry.

Growth performance, carcass traits and digestive function of broiler chickens fed diets with graded levels of corn resistant starch

ABSTRACT1. This study was conducted to assess the effects of graded levels of dietary corn resistant starch (RS) on growth performance, carcass traits, nutrient retention, digestive organ index, intestinal morphology, digestive enzyme activities, and mRNA expression of certain nutrient transporters in broiler chickens.2. A total of 320, 1-d-old Arbor Acres broiler chickens were randomly assigned to five dietary treatments, with eight replicates of eight birds in each. These treatments included one corn-soybean control diet, a corn-soybean based diet containing 20% corn starch, and three diets supplemented with 4%, 8% and 12% RS by replacing corn starch with 6.67%, 13.33% and 20% of Hi-Maize 260® (identified as control, RS1, RS2, RS3 and RS4, respectively). The feeding period lasted 42 days.3. Performance parameters including feed consumption, feed conversion, body weight gain and percentage of abdominal fat at d 42 of age, nutrient retention (including dry matter, fat, total starch and nitrogen free extract), and apparent metabolisable energy was measured from d 18 to 20 and d 39 to 41 and showed negative linear responses to increasing dietary RS level (P < 0.05). Birds fed the RS3 and RS4 diets showed higher relative weight of duodenum, jejunum and ileum, as well as lower villus height and villus height/crypt depth compared to the control (P < 0.05). The activity of pancreatic trypsin of birds at d 21 and 42 of age decreased linearly in response to the increase of dietary RS level (P < 0.01). There were linear changes in up-regulated mRNA expression of SGLT-1 and down-regulated mRNA expression of GLUT-2 with increasing proportion of RS at d 21 and 42 of age (P < 0.05), respectively.4. It was concluded that feeding broilers with diets containing higher concentrations of RS impaired the development of small intestine, which resulted in lower apparent total tract retention of nutrients and poorer body weight gain, feed efficiency and carcass traits of broiler chickens.

Development and Preliminary Validation of a Feasible Procedure for Isolating RNA from Fiber-Adherent Bacteria in Human Stool.

BackgroundIntestinal bacterial communities are not homogenous throughout the gastrointestinal tract. Human research on the gut microbiome often neglects intra-intestinal variability by relying on a single measurement from stool samples. One source of complexity is the adherence to undigested, residual fiber. Currently, no procedure exists to extract RNA from distinct bacterial subpopulations in stool samples.Material/MethodsA serial centrifugation procedure was developed in which bacterial RNA could be extracted from distinct stool-fractions – fiber-adherent and non-fiber-adherent bacteria. To test whether the separation procedure yielded distinct bacterial subpopulations, a set of RT-qPCR assays were developed for a fiber-adherent bacterial species, Bifidobacterium adolescentis, then a within-subject repeated-measures study was conducted with 3 human subjects undergoing 4 dietary regimens. At each timepoint, between-fraction differences in gene expression were evaluated.ResultsThe RNA isolation procedure was able to isolate intact RNA in 20 of 24 samples in the fiber-adherent fraction. PurB and sdh were identified as suitable reference genes for B. adolescentis RT-qPCR assays. When subjects were provided a high resistant starch diet, bacterial fractions exhibited different expression of the trp operon (p=0.031).ConclusionsOur study provides human gut microbiome researchers a novel tool for evaluating functional characteristics of bacterial subpopulations in human stool. Moreover, these experiments provide modest support for the existence of a functionally unique fiber-adherent subpopulation of B. adolescentis. Until a more thorough evaluation of the adherent and non-adherent fraction can be performed, researchers should be cautious when generalizing functional data derived solely from unfractionated stool samples.

Effect of native and acetylated dietary resistant starches on intestinal fermentative capacity of normal and stunted children in southern India.

Effect of native and acetylated dietary resistant starches on intestinal fermentative capacity of normal and stunted children in southern India.

The effects of age and dietary resistant starch on digestibility, fermentation end products in faeces and postprandial glucose and insulin responses of dogs

ABSTRACTThe same food formulation processed to obtain two different starch gelatinisations (SG) and resistant starch (RS) contents was evaluated in old and adult dogs, regarding apparent total tract digestibility (ATTD) of nutrients, fermentation products in faeces, and postprandial glucose and insulin responses. A diet with corn was ground and extruded in two different ways, obtaining Low RS (2.2 g/kg DM; 99.9% of SG) and High RS (15.3 g/kg DM; 62.6% of SG). Each diet was fed to adults (4.0 ± 0.7 years) or old beagle dogs (11.5 ± 0.4 years) in a 2 (ages) x 2 (RS amounts) factorial arrangement with 8 dogs per food. Data were evaluated by analysis of variance, and postprandial responses by analysis of variance of repeated measurements over time (p < 0.05). Diet × age interaction was observed for protein ATTD, with lower values for old dogs fed High RS than those for the other treatments (p < 0.05). No age or diet effect was verified for the ATTD of other nutrients and faecal score. Faecal moisture and pH were higher for adults than that for old dogs (p < 0.05). The High RS food increased acetate, propionate and butyrate concentrations in faeces, regardless of age (p < 0.01). Old dogs presented lower acetate and total short-chain fatty acids (SCFA) and higher lactate and ammonia than adults (p < 0.05). Only for old dogs the intake of the High RS food reduced ammonia and increased faecal lactate (p < 0.05). An age × diet interaction was verified for glucose postprandial response, with lower values for old dogs fed High RS food (p < 0.05), while no differences were found for the other treatments. Old dogs had higher postprandial insulin secretion regardless of the diet (p < 0.05), and lower insulin increment at 180 min after the meal when fed the Low RS than when fed the High RS food (p < 0.05). In conclusion, the diet with lower SG and higher RS improved the intestinal microenvironment, with higher butyrate and total SCFA without altering faeces production or score. Old dogs presented less acetate and total SCFA and higher lactate and ammonia in faeces than adults. The High RS food increased lactate and reduced ammonia in faeces of old dogs, with possible positive influences for gut health. Old dogs had higher postprandial insulin secretion than that of adults to maintain blood glucose, and the diet with higher RS content reduced the postprandial glucose response of old dogs.