FOOD CARBOHYDRATE STRUCTURE-FUNCTION STUDIES RELATED TO NUTRITION AND HEALTH

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1017338
• Project Start Date: Oct 5, 2018
• Project End Date: Sep 30, 2023
• Program Code: [(N/A)]- (N/A)

Recipient Organization
PURDUE UNIVERSITY
(N/A)
WEST LAFAYETTE,IN 47907

Performing Department
Food Science

Non Technical Summary
Today, there is an increased awareness of the role of diet to health that is particularly related to obesity and its associated chronic, debilitating diseases of diabetes and cardiovascular disease. In the last 30-40 years, we have seen obesity rates rise dramatically and unsettlingly not only in Western, industrialized countries, but also in the developing world such as African urban areas. The interest of our research laboratory is to understand, at a fundamental level, how carbohydrate-based foods may be contributing to this problem, and more importantly how changes in design of such foods can be made to improve health. This endeavor is necessarily multi-disciplinary in nature making it imperative for food scientists to work with collaborators in the biological field. Moreover, in recent years it has become apparent that the state of the gut microbiome is related to these and other chronic non-communicable diseases, especially those affected by chronic systemic inflammation and breakdown in gut barrier function. A frontier area in research has opened up regarding how to improve gut health related to these disease states by using dietary fiber to make changes in gut microbiota structure and fermentation metabolite profiles. These are some of the biggest opportunities in food science related to human health. We have found that locational differences in glycemic carbohydrate digestion, with some of it occurring in the distal ileal section of the small intestines, activates the gut-brain axis and ileal brake mechanism that has a marked effect of reducing food intake in diet-induced obese rats animals and increasing stomach emptying time. This is an opportune time to understand how to design carbohydrate-based foods that will provide satiety, extend energy delivery to the body, and reduce food intake. Our knowledge of carbohydrate chemical and physical structures, and gaining knowledge of natural partial inhibitors of the enzymes that digest glycemic carbohydrates (e.g., starch, starch products, other α-linked glucans), allows us to focus research to this larger goal of truly understanding how to make demonstrable healthy carbohydrate-based foods. This could have application in the processed food industry to make healthier products, as well as possibly in the medical field as precise vehicles to provide targeted glucose release for maximal weight management effect. In the area of dietary fiber and gut health related to whole body health, an opportunity exists to understand how specific fiber structures can favor certain bacteria or bacterial groups to manipulate the microbiota for improved health outcomes. This, and understanding how fiber mixtures can be designed to create a better colonic environment for such endpoints as lowering inflammation and improving barrier function, are the central goals of the proposed research. In the future, fibers blends are envisioned that will be used to maintain good gut health and that might be used therapeutically to address diseases and conditions that are dependent on microbiota balance and other aspects of a healthy colon environment. Dietary fibers must also be palatable and acceptable to the consumer in amounts that are significant enough to affect positive change in the colon. Identification of fibers and processing strategies that can be used to make fibers more acceptable, and which are tolerable in comparably high incorporation amounts will be important for consumer acceptance and are incorporated into our research program. Overall, our aim is to understand the fundamentals of how food carbohydrates interact with the gastrointestinal tract to positively affect gut health and physiology. Our targeted approach of using dietary carbohydrates addresses health-related endpoints of glucose homeostasis related to diabetes and obesity, appetite and weight management, and systemic inflammation and a number of chronic non-communicable diseases.

Animal Health Component

50%

Research Effort Categories

Basic

30%

Applied

50%

Developmental

20%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
702	1599	1010	25%
502	1599	1000	30%
704	1599	1010	15%
501	1599	1000	10%
702	1599	1000	10%
702	1459	1010	10%

Knowledge Area
702 - Requirements and Function of Nutrients and Other Food Components; 501 - New and Improved Food Processing Technologies; 704 - Nutrition and Hunger in the Population; 502 - New and Improved Food Products;

Subject Of Investigation
1599 - Grain crops, general/other; 1459 - Rhizomes, tubers, bulbs, and root crops, general/other;

Field Of Science
1010 - Nutrition and metabolism; 1000 - Biochemistry and biophysics;

Keywords

food

carbohydrates

protein

starch

glycemic

gut hormones

obesity

food intake

dietary fiber

gut microbiome

africa

rheology

food chemistry

nutrition

Goals / Objectives
The overall goal of this project is to find new ways to design carbohydrate-based foods for health, based on an improved understanding of how carbohydrates are used by the body upper gastrointestinal tract and lower gut microbiota. Our interest is both to identify and modify whole foods, and molecular and physical structures of ingredients, for improved function in the body for novel food applications. This project also has applications to developing countries with focus on Africa, such as to mechanically process traditional foods that are satiating, have moderated glycemic response, and provide extended energy post consumption.1. Based on a previous finding that ileal location of digestion of glycemic carbohydrates (e.g., starch, maltodextrins, sucrose, other α-linked glucans) activates the gut-brain axis and reduces food intake of obese animals, we will develop carbohydrate-based ingredients and foods for health.a. To design delivery vehicles for optimized location-specific glucose release for weight reduction targeted to the obesity problem.b. To develop satiating foods for industrialized countries and Africa to promote health, and to be used to promote locally grown crops in Africa.c. To conduct collaborative studies to understand further how slow carbohydrate digestion improve health.2. To understand better the relationship between dietary fiber structures and requirements of growth of colonic bacteria to develop strategies to promote colonic health through manipulations of the microbiota.3. To identify ways, based on dietary fiber structures and their rheological behaviors, for high incorporation into processed foods with desirable sensory properties.4. To further investigate how non-wheat cereal grain storage proteins can be transformed to functional food proteins with viscoelastic properties for gluten-free application and high local cereal incorporation flours in Africa

Project Methods
Due to the cross-disciplinary nature of the proposed work, in recent years our group has moved more towards the biological side of the research questions we propose, using cell culture, in vitro fecal fermentation systems, and in vivo rodent and human studies. We collaborate with scientists from a number of other disciplines and will continue to do so in the studies proposed here. Objective 1: This aim focuses on designing glycemic (i.e., available) carbohydrates to digest into the distal part of the small intestine (ileum) to activate the enteroendocrine L-cells located there to study the triggering of the gut-brain axis through secrete appropriate gut hormones, and related ileal brake mechanism, to reduce appetite, slow gastric emptying rate, increase satiety, and reduce food intake. For the manipulation of rate and location of glycemic carbohydrate digestion/glucose generation for maximum beneficial physiological effect, we will work with 4 collaborative groups: 1) a Purdue appetite expert (R. Mattes), and Indiana University radiologist (P. Territo); 2) our "Starch Digestion Consortium" with experts on the mucosal alpha-glucosidases as a main control point for starch digestion including a gastroenterologist (B. Nichols), enzymologist (R. Quezada-Calvillo), protein modeler (D. Rose), and cell biochemist (H. Naim); 3) clinical researchers at Rush University Medical School who will test materials in clinical experiments; and 4) a food structure and formulation engineer at University of Guelph (M. Martinez). Structure-function studies will be done on existing and modified starch structures and mixed linkageα-glucans with slow digesting property, and combining of slow digesting structures with partialα-amylase andα-glucosidase natural phenolic inhibitors, to align digestion into the animal or human ileum. Animal studies (mouse or rat, normal or diet-induced obese) will be conducted to further understand whether distal small intestine glucose release materials can be used for a diet-based strategy for weight reduction or management. Such slow glucose release materials will be tested in animal models for effect on food intake behavior, gut and incretin hormones, and hypothalamic neuropeptide levels, and other potential indicators of related to blood glucose levels (e.g., glycated hemoglobin), and humans for gastric emptying rate (using a non-invasive 13C-octanoic acid breath test method) and including such indicators as cognitive and activity-related performance. We will conduct an initial study to answer the question of whether similar results to bariatric surgery for the morbidly obese can be obtained through a precise, targeted dietary approach to optimize glucose release to gut hormone releasing L-cells. Human studies may also be done in the course of this work to understand further the effect of glycemic carbohydrate digestion on gastric emptying rate, postprandial glycemic response, appetitive response, and gut hormones. In earlier studies of ours, a gender effect was seen in that female participants were more responsive than males to slowly digestible carbohydrates, and this may also be further pursued. The hope will be to attain supporting data for grants for larger clinical studies related to the efficacy of such a dietary approach to control appetite and physiology for weight and disease management. Our previous work in Africa showed that traditional sorghum and millet-based foods have significantly slower gastric emptying in the human, and we plan to continue this work to understand how these foods might be promoted on the basis of their being satiating and providing extended energy post consumption. This is related to an overall aim of that work to increase local grain markets for farmers.Objective 2: Our current and proposed work focuses on use of dietary fiber chemical and physical structures to create shifts in the colon microbiota to improve gut and related whole body health. Our (B. Hamaker and B. Reuhs) collaborators will include a clinical group at Rush University Medical School to study the effect of fibers related to disease conditions, gut microbial ecologists at Purdue (S. Lindenmann) and Rutgers University (L. Zhao), and a gut molecular microbiologist at University of Michigan (E. Martens). We will continue to study the role of different fermentable dietary fiber structures (e.g., plant cell wall matrix fibers, extracted arabinoxylans, xyloglucans, resistant starch, oligosaccharides, etc.) on conditions and diseases related to the colon including barrier function and inflammatory response, fiber structures that are slow fermenting and tolerable and that ferment into the distal colon, and fiber structures and mixtures to promote certain microbiota changes that are desirable for health. Of particular interest will be fiber fermentation responses in microbiota of different human individuals and populations. Studies will be done using in vitro fecal fermentation tests for rates of fermentation, short chain fatty acid products, and microbiota changes (using 16S rDNA sequencing), and possibly in test animals and humans. Structure-function studies will focus on single bacteria strain and artificial community utilization of defined polysaccharide and oligosaccharide structures to better understand how gut bacteria compete on fibers (in collaboration with E. Martens). RT-qPCR will be used to monitor specific gut bacteria species of interest (e.g., butyrogenic bacteria). We will conduct studies on chemical structures of dietary fiber polysaccharides and oligosaccharides using equipment available in the Reuhs and Hamaker labs (which are part of the Whistler Center facilities) or the Purdue Mass Spectrometry Center. This includes gas chromatography for carbohydrate content determination and gas chromatography-mass spectrometry for linkage analysis. We will use various types of mass spectrometers for oligosaccharide size analysis and MS-MS to obtain sequence and branch information. We have a 300 MHz nuclear magnetic resonance instrument that will provide a variety of structural information, and there are higher field instruments available in the Purdue NMR facility should they be necessary.Objective 3: With O. Campanella and O. Jones, we (B. Hamaker and B. Reuhs) will continue to investigate the relationship between dietary fiber structures and their physical functionality in foods to find ways to incorporate high amounts of fibers with good texture-related sensory properties. We will investigate both supramolecular and molecular structures of plant fiber fractions to relate polysaccharide structural properties, and their hydrolyzates, to rheological function and product quality. Characterization techniques such as GC monosaccharide profiling, and GC-MS partial methylation linkage analysis will be used to understand chemical structures of fiber polymers; and methods, such as dynamic and static light scattering, will be used for determination of broader structural and shape aspects. Rheological assessment will be done using oscillatory dynamic tests and large strain deformation, and capillary rheometry.Objective 4: We have reported on a way to make corn zein or sorghum kafirin seed prolamin storage proteins take on a viscoelastic property that, while not exactly mimicking wheat gluten, has dough forming characteristics. Research will continue to use this protein technology to improve gluten-free baked products and to form viscoelastic functional doughs from sorghum grain. This is related to research we have done on Purdue's high digestibility/high-lysine sorghum cultivar where we showed has freed kafirin protein that can be made to participate in a sorghum/wheat composite flour for breadmaking.

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:Food, nutrition and medical scientists, and the food industry, involved in or interfacing with the foods for health area. In Africa, target groups are governmental development agencies, research centers and non-governmental organizationsassociated with crop value-chains, processed product technologies and markets. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students (8, 2 MS, 6 PhD) and post-doctoral research associates (5) were trained under this project during thisperiod, as well as 3 visiting scientists. Two PhD and one MS student completed their degrees during this period. How have the results been disseminated to communities of interest?Results were disseminated through refereed publications, and presentations at domestic and international conferences.Research findings were presented to industrial members of the Whistler Center for Carbohydrate Research and indiscussions with other industry visitors. What do you plan to do during the next reporting period to accomplish the goals?We will continue our work described above towards 1) designing slowly digestible carbohydrates with distal small intestine digestion to food materials to activate the gut-brain axis and ileal brake for purpose of appetite control, 2) understanding how dietary fibers chemical and physical structures can be aligned to support specific beneficial gut bacteria or bacterial groups to improve localized gut and whole body health, and 3) getting back into the plant-based protein research area by extending ourpast work on viscoelastic property of corn zein, and other similar proteins, to practical applications related to current market demands.

Impacts
What was accomplished under these goals? 1.a. Some further progress was made this year in the understanding of how to direct dietary carbohydrates to digest locationally in the distal small intestine (ileum) to activate the gut-brain axis for appetite control. We had shown previously that when carbohydrates were fabricated to digest throughout the small intestine of rodents and into the ileum that a gut hormone (GLP-1) mediated communication with the brain hypothalamus was triggered that resulted in lower food intake and reduced weight gain in lean animals on an obesogenic high-fat diet, and increased weight loss in obese animals on a low-fat weight reducing diet. Also, specific flavonoid structures for alpha-amylase inhibition slowed starch digestion into the ileum with coinciding gut-brain axis communication affecting appetite and weight. In this year, we did testing on combining factors to get ileal carbohydrate digestion that could be used in regular foods. Our goal is to understand how to make slowly digestible gut-brain axis activating carbohydrate ingredients that can be used in processed foods for appetite control and weight management. 1.b. A human crossover design study had been done to examine millet-based foods and their hypothesized slowly digestible starch property. Data was analyzed and a paper has been accepted and on-line (Hayes et al., British Journal of Nutrition) showing that some millet foods (e.g. millet couscous), commonly consumed in West Africa, have a lower postprandial glycemic response than white rice. This goes along with anectodol evidence that millet-based foods in West Africa are satiating and provide sustained energy. 2. Studies have continued on dietary fibers and the gut microbiome, using in vitro human fecal fermentation, with focus on: 1) alignment of fiber polysaccharide structures to either individual gut bacteria or bacterial groups and how fibers can be used for predictable microbiota shifts and outcomes, 2) whole food fibers compared to isolated fibers and fructooligosaccharide (FOS) prebiotic, and 3) how extrusion processing of cereal bran fibers can be used to improve their fermentation and value to the gut microbiota. We published a concept paper (Cantu-Jungles and Hamaker, mBio, 2020) proposing that fermentable dietary fibers might be classified in a hiearchical sense based on chemical and physical complexity. Fibers with high specificity of structure are more aligned to specific bacteria or bacterial groups, and lead to more consistent gut microbial community responses, opposed to low specificity fibers that have a differential responses bases on the community composition. An experimental paper that supports the concept is in review. Whole food fibers surprisingly were well fermented and almost as much as FOS, while isolated fibers were not. Extrusion processing of corn bran increased gut microbiota fermentability. 4. We received a USDA FFAR grant this year on corn zein protein, and have started again work this time on zein (decolorized, deodorized) as a viscoelastic cohesive protein that can be used to complement soy and pea-based proteins as they are used in meat analogues.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Roman, L., Gomez, M., Hamaker, B., Martinez, M. M. 2019. Banana starch and molecular shear fragmentation dramatically increase structurally driven slowly digestible starch in fully gelatinized bread crumb. Food Chemistry 274:664-671.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Fang, F. Martinez, M.M., Campanella, O.H., Hamaker, B.R. 2020. Long-term low shear induced highly viscous waxy potato starch gel formed through intermolecular double-helices. Carbohydrate Polymers 232:115815.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Hayes, A.M.R Swackhamer, C., Mennah-Govela, Y., Martinez, M.M., Diatta, A., Bornhorst, G.M., Hamaker, B.R. 2020. Pearl millet (Pennisetum glaucum) couscous breaks down faster than wheat couscous in the Human Gastric Simulator, though has slower starch hydrolysis. Food & Function 11:111-122.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Ferruzzi, M.G., Hamaker, B.R., Bordenave, N. 2020. Phenolic compounds are less degraded in presence of starch than in presence of proteins through processing in model porridges. Food Chemistry 309:125769.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Fang, F., Luo, X., BeMiller, J.N., Schaffter, S., Hayes, A.M.R., Woodbury, T.J., Hamaker, B.R., Campanella, O.H. Neutral hydrocolloids promote shear-induced elasticity and gel strength of a gelatinized waxy potato starch. Food Hydrocolloids 107:105923.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Fang, F., Luo, X., Fei, X., Mathews, M., Lim, J., Hamaker, B.R., Campanella, O.H. A stored gelatinized waxy potato starch forms a strong retrograded gel at low pH with formation of intermolecular double helices. Journal of Agricultural and Food Chemistry 68:4036-4041.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: te Poele, E.M., Corwin, S.G., Hamaker, B.R., Lamothe, L.M., Vafiadi, C., Dijkhuizen, L. 2020. Development of slowly digestible starch derivatives with 2 4,6-?-glucanotransferase and branching sucrase enzymes, Journal of Agricultural and Food Chemistry 68: 6664-6671.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Tuncil, Y.E., Thakkar, R.D., Arioglu-Tuncil, S., Hamaker, B.R., Lindemann, S.R. 2020. Subtle variations in dietary-fiber fine structure differentially influence the composition and metabolic function of gut microbiota. mSphere DOI: 10.1128/mSphere.00180-20.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Thakkar, R., Tuncil, Y.E., Hamaker, B.R., Lindemann, S.R. 2020. Maize bran size fraction governs the community composition and metabolic output of human gut microbiota. Frontiers in Microbiology 11:1009.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Cantu-Jungles, T.M., Hamaker, B.R. 2020. A new view on dietary fiber selection for predictable shifts in the gut microbiota. mBio 11:e02179-19.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Hasek, L.Y, Phillips, R.J., Kinzig, K., Zhang G., Powley, T.L., Hamaker, B.R. 2020. Carbohydrates designed with different digestion rates modulate gastric emptying and glycemic/insulinemic responses in rats. International Journal of Food Sciences and Nutrition 1-6, on-line DOI: 10.1080/09637486.2020.1738355.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: De Groote, H., Mugalavai, V., Ferruzzi, M., Onkware, A., Ayua, E., Duodu, K., Ndegwa, M., Hamaker, B. 2020. Consumer acceptance and willingness to pay for instant fortified cereal products in Eldoret, Kenya. Food and Nutrition Bulletin on-line https://doi.org/10.1177/0379572119876848.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Hasek, L.Y., Avery, S.E., Chacko, S.K., Fraley, J,K., Vohra, F.A., Quezada-Calvillo, R., Nichols, B.L., Hamaker, B.R. 2020. Conditioning with slowly digestible starch diets in mice reduces jejunal ?-glucosidase activity, and glucogenesis from a digestible starch feeding. Nutrition 78:110857.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Gu, F., Li, C., Hamaker, B.R., Gilbert, R.G., Zhang, X. 2020. Fecal microbiota responses to rice RS3 are specific to amylose molecular structure. Carbohydrate Polymers 243:116475.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Erickson, D.P., Ozturk, O.K., Selling, G., Chen, F., Campanella, O.H., Hamaker, B.R. 2020. Corn zein undergoes conformational changes to higher ?-sheets contents during its self-assembly in an increasingly hydrophilic solvent. International Journal of Biological Macromolecules 157:232-239.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Hamaker, B.R., Cantu-Jungles, T.M. 2020. Discrete fiber structures dictate human gut bacteria outcomes. Trends in Endocrinology & Metabolism 31:803-805.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Hayes AMR, Okoniewska O, Martinez MM, Zhao B, Hamaker BR. 2020. Investigating the potential of slow-retrograding starches to reduce staling over time in soft savory bread and sweet cake model systems. Food Research International 138: 109745.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Roman L, Yee J, Hayes AMR, Bertoft E, Hamaker BR, Mart�nez MM. On the role of the internal chain length distribution of amylopectins during retrogradation: double helix lateral aggregation and slow digestibility. Carbohydrate Polymers 246:116633.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Fevzioglu, M., Ozturk, O.K., Hamaker, B.R., Campanella, O.H. 2020. Quantitative approach to study secondary structure of protein systems by FT-IR spectroscopy, using a model wheat gluten system. International Journal of Biological Macromolecules 164: 2753-2760.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Nguyen, N.K., Deehan, E.C., Zhang, Z. Jin, M., Baskota, N., Perez-Mu�oz, M.E., Cole, J., Tuncil, Y.E., Seethaler, B., Wang, T., Laville, M., Delzenne, N.M., Bischoff, S.C., Hamaker, B.R., Mart�nez, I., Knights, D., Bakal, J.A., Prado, C.M., Walter, J. 2020. Gut microbiota modulation with long-chain corn bran arabinoxylan in overweight individuals is linked to an individualized temporal increase in fecal propionate. Microbiome 8:1-21.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: 264. Fang, F., Hayes, A.M.R., Watanabe, H., Higashiyama, T., Campanella, O.H., Hamaker, B.R. 2020. Isomaltodextrin strengthens model starch gels and moderately promotes starch retrogradation. International Journal of Food Science & Technology https://doi.org/10.1111/ijfs.14782.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Ayua, E.O., Kazem, A.E., Hamaker, B.R. 2020. Whole grain cereal fibers and their support of the gut commensal Clostridia for health. Bioactive Carbohydrates and Dietary Fibre 24:100245.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Moser, S.E., Shin, J.E., Kasturi, P., Hamaker, B.R., Ferruzzi, M.G., Bordenave, N. 2020. Formulation of orange juice with dietary fibers enhances bioaccessibility of orange flavonoids in juice but limits their ability to inhibit in vitro glucose transport. Journal of Agricultural and Food Chemistry 68: 9387-9397.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Engen, P.A., Zaferiou, A., Rasmussen, H., Naqib, A., Green, S.J., Fogg, L.F., Forsyth, C.B., Raeisi, S., Hamaker, B., Keshavarzian, A. 2020. Single-arm, non-randomized, time series, single-subject study of fecal microbiota transplantation in multiple sclerosis. Frontiers in Neurology 11:978.

Progress 10/05/18 to 09/30/19

Outputs
Target Audience:Food, nutrition and medical scientists, and the food industry, involved in or interfacing with the foods for health area. In Africa, target groups are governmental development agencies, research centers and non-governmental organizations associated with crop value-chains, processed product technologies and markets. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students (12, 3 MS, 9 PhD) and post-doctoral research associates (2) were trained under this project during this period, as well as 5 visiting scientists. One PhD student completed his degree during this period. How have the results been disseminated to communities of interest?Results were disseminated through refereed publications, and presentations at domestic and international conferences. Research findings were presented to industrial members of the Whistler Center for Carbohydrate Research and in discussions with other industry visitors. What do you plan to do during the next reporting period to accomplish the goals?We will continue our work described above towards 1) designing slowly digestible carbohydrates with distal small intestine digestion to food materials to activate the gut-brain axis and ileal brake for purpose of appetite control, 2) understanding how dietary fibers chemical and physical structures can be aligned to support specific beneficial gut bacteria or bacterial groups to improve localized gut and whole body health, and 3) getting back into the plant-based protein research area by extending our past work on viscoelastic property of corn zein, and other similar proteins, to practical applications related to current market demands.

Impacts
What was accomplished under these goals? Accomplishments for this period are as follows: 1.a.b.c. Previously we have reported the design and fabrication of a slowly digestible starch material that locationally digests throughout the small intestine and to completion in the distal part called the ileum. When fed to obese lab animals (rats and mice), this material activated the gut-brain communication axis and accordingly reduced food intake and increased weight reduction when they were transferred to a low-fat normal diet. Also, lean young mice fed on an obesogenic high-fat diet with the slowly digestible material gained weight at a slow rate similar to the low-fat control group. We have further found that natural phenolic compounds found in common foods can inhibit the starch-degrading enzymes to slow starch digestion in the small intestine and to activate the gut-brain axis. After screening a large number of flavonoids, with systematic changes to chemical structures (i.e. position of -OH groups and presence or absence of the C-ring double-bond), candidate inhibitors were found that specifically inhibited in vitro alpha-amylase or the mucosal alpha-glucosidases. In mice studies, it was found that flavonoids specific to alpha-amylase digestion were effective when combined with starch to slow digestion and trigger the gut-brain axis, as measured by elevated amounts of glucagon-like peptide-1 (GLP-1) and gene expression differences for the hypothalamic appetite stimulating and suppressing neuropeptides in the brain. This work further supports our postulate that slowly digestible carbohydrates provided in whole or processed foods can activate the gut-brain axis, an important physiological feedback system in the body for appetite control. Our interest is to find or fabricate carbohydrate materials that can be put in regular foods, including even highly processed (i.e. "ultra-processed") foods that would increase satiety response and reduce desire to eat for weight management. This concept turns consumer's current view of carbohydrates as fat-inducing to fat-reducing, and we believe is achievable now in the coming few years. We are working with another collaborator/scientist with expertise in formulations and processing who has developed some promising prototype carbohydrate-based materials that could trigger the gut-brain axis. In our work in Africa, we received funding through a local program, which is supported through NIH, to conduct a human study in the US and Kenya on slowly digestible carbohydrates and their proposed different responses for another physiological feedback system in the body, the ileal brake which slows stomach emptying. We have previously shown that slowly digestible carbohydrates slow stomach emptying in an African study, but in the US we only showed that a sub-group of subjects responded in this way. The new study allows us to compare directly response of stomach emptying rate to slowly digestible carbohydrates in US and Kenyan subjects and, through diet intake data, to understand if the type of diets the populations typically consume has an effect on their response. 2. We have made good advances in our research on understanding relationships between dietary fiber chemical and physical structures and gut bacterial responses. Our interest and goal is to figure out how to align fiber structures to the specific needs of certain beneficial gut bacteria or bacterial groups, and to understand how competition for fiber substrates by different gut bacterial communities changes the effect. We have found over the last few years that fibers with higher degree of chemical and, importantly, physical complexity tend to be more aligned to specified gut bacteria. An accomplishment in this period is that we showed that specifically aligned fibers that support targeted bacteria are more likely to have the same effect over different individuals, while more generalized less specific fibers have different effects in different individuals that are due to different competitive environments of their bacterial communities. On the practical side, this insight allows us and others to develop ways/protocols to identify fibers that align to beneficial bacteria for their support and ultimately to begin using fibers to achieve predictable results in a human population to support beneficial bacteria for both gut and whole body health. 4. Although we did not do research in the area of plant-based proteins, in this year we have submitted a proposal to USDA NIFA building on our past extensive work with O. Campanella (now at Ohio State University) towards functionalizing corn zein (and other similar) proteins to impart a missing viscoelastic property in commodity plant-based proteins used in the food industry (pea and soybean), and to develop new protein-carbohydrate functional viscoelastic materials. Also, we are active in submitting previous manuscripts on this subject for publication.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, M., George, J., Hunter, S., Hamaker, B.R., Mattes, R.D., Ferruzzi*, M.G. 2019. Potato product form impacts in vitro starch digestibility and glucose transport but only modestly impacts 24h blood glucose response in humans. Food & Function 10:1846-1855. (IF=3.241)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Na-Nakorn, K., Kulrattanarak, T., Hamaker*, B.R., Tongta*, S. 2019. Starch digestion kinetics of extruded reformed rice is changed in different ways with added protein or fiber. Food & Function 10:4577-4583. (IF=3.241)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Cantu-Jungles, T.M., Rasmussen*, H.E., Hamaker, B.R. 2019. Potential of prebiotic butyrogenic fibers in Parkinsons disease. Frontiers in Neurology https://doi.org/10.3389/fneur.2019.00663. (IF=2.635)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Tun�il, Y.E., Fevzioglu, M., Arioglu-Tun�il, S., Ejeta, G., Campanella, O.H., Hamaker*, B.R. 2019. Transglutaminase shows better functionality on high digestible, high lysine sorghum-wheat composite dough and bread, compared to normal sorghum-wheat composites. Turkish Journal of Agriculture  Food Science and Technology 7:6.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Schmidt*, G. Woods, J.T., Fung, L.X-B., Gilpin, C.J., Hamaker, B.R., Wilker, J.J. 2019. Strong adhesives from corn protein and tannic acid. Advanced Sustainable Systems 3:1900077.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Debelo, H., Ndiaye, C., Kruger, J., Hamaker, B., Ferruzzi*, M.G. 2019. African Adansonia digitata fruit pulp (baobab) modifies provitamin A carotenoid bioaccessibility from composite pearl millet porridges. Journal of Food Science and Technology doi:10.1007/s13197-019-04173-y. (IF=1.850)
• Type: Journal Articles Status: Awaiting Publication Year Published: 2019 Citation: De Groote*, H., Mugalavai, V., Ferruzzi, M., Onkware, A., Ayua, E., Duodu, K., Ndegwa, M., Hamaker, B. 2019. Consumer acceptance and willingness to pay for instant fortified cereal products in Eldoret, Kenya. Food and Nutrition Bulletin, in press. (IF=1.523)
• Type: Journal Articles Status: Accepted Year Published: 2019 Citation: 1. Cantu-Jungles, T.M., Hamaker*, B.R. 2019. A new view on dietary fiber selection for predictable shifts in the gut microbiota. mBio, in press. (IF=6.747)
• Type: Journal Articles Status: Submitted Year Published: 2019 Citation: 1. Fevzioglu, M., Ozturk, O.K., Hamaker, B.R., Campanella, O.H. 2019. Quantitative approach to study secondary structure of protein systems by FT-IR spectroscopy, using a model wheat gluten system. Food Chemistry, submitted.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Liu, G., Gilding, E.K., Kerr, E.D., Schulz, B.L., Tabet, B., Hamaker, B.R., Godwin*, I.D. 2019. Increasing protein content and digestibility in sorghum grain with a synthetic biology approach. Journal of Cereal Science 85:27-34. (IF=2.452)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Cantu-Jungles, T.M., Nascimento, G.E., Zhang, X., Iacomini, M., Cordeiro*, L.M.C., Hamaker*, B.R. 2019. Soluble xyloglucan generates bigger bacterial community shifts than pectic polymers during in vitro fecal fermentation. Carbohydrate Polymers 206:389-395. (IF=6.044)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Kaur, A., Chen, T., Green, S., Mutlu, E., Martin, B., Rumpagaporn, P., Keshavarzian, A., Hamaker*, B.R. 2019. Physical inaccessibility of a resistant starch to Bacteroidetes shifts mouse gut microbiota to butyrogenic Firmicutes. Molecular Nutrition and Food Research 63:1081012, https://doi.org/10.1002/mnfr.201801012. (IF=4.653)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Zhang, X., Chen, T., Lim, J., Gu, F., Fang, F., Cheng, L., Campanella, O.H., Hamaker*, B.R. 2019. Acid gelation of soluble laccase-crosslinked corn bran arabinoxylan and possible gel formation mechanism. Food Hydrocolloids 92:1-9. (IF=5.839)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Tejada-Ortigoza, V., Garcia-Amezquita, L.E., Kazem, A.E., Campanella, O.H., Cano, M.P., Hamaker, B.R., Serna-Sald�var, S.O., Welti-Chanes*, J. 2019. In vitro fecal fermentation of high pressure treated fruit peels used as dietary fibre sources. Molecules 24:697 https://doi.org/10.3390/molecules24040697. (IF=3.060)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Lim, J., Zhang, X., Ferruzzi, M.G., Hamaker*, B.R. 2019. Starch digested product analysis by HPAEC reveals structural specificity of flavonoids in the inhibition of mammalian ?-amylase and ?-glucosidases. Food Chemistry 288:413-421. (IF=5.399)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Liu, J., Johnson, R., Dillon, S., Kroehl, M., Frank, D.N., Tuncil, Y.E., Zhang, X., Ir, D., Robertson, C.E., Seifert, S., Higgins, J., Hamaker, B., Wilson*, C.C., Erlandson*, K.M. 2019. Among older adults, age-related changes in the stool microbiome differ by HIV-1 serostatus. EBioMedicine 40:583-594. (IF=6.680)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Nkhata, S.G., Ortiz, D., Baributsa, D., Hamaker, B., Rocheford, T., Ferruzzi*, M.G. 2019. Assessment of oxygen sequestration on effectiveness of Purdue Improved Crop Storage (PICS) bags in reducing carotenoid degradation during post-harvest storage of two biofortified orange maize genotypes. Journal of Cereal Science 87:68-77. (IF=2.452)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Lim, J., Kim, D.K., Shin, H., Hamaker*, B.R., Lee*, B.H. 2019. Different inhibition properties of catechins on the individual subunits of mucosal ?-glucosidases as measured by partially-purified rat intestinal extract. Food & Function 10:4407-4413 doi:10.1039/C9FO00990F. (IF=3.241)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Zhang, X., Chen, T., Lim, J., Xie, J., Zhang, B., Yao, T., Hamaker*, B.R. 2019. Fabrication of a soluble crosslinked corn bran arabinoxylan matrix supports a shift to butyrogenic gut bacteria. Food & Function 10, 4497-4504. (IF=3.241)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Cheng, L., Zhu, X., Zhang, H., Hamaker, B.R., Zhang, H., Campanella*, O.H. 2019. Complexation process of amylose with different concentrations of linoleic acid using molecular dynamics simulation. Carbohydrate Polymers 216:157-166. (IF=6.044)