|An automated modular microsystem for enzymatic digestion with gut-on-a-chip applications
Haan, P. de; Ianovska, M.A. ; Mathwig, K. ; Bouwmeester, H. ; Verpoorte, E. - \ 2020
In: 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017. - Chemical and Biological Microsystems Society (21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017 ) - ISBN 9780692941836 - p. 1593 - 1594.
Digestion - Enzyme kinetics - Gut-on-a-chip - Organ-on-a-chip
Gut-on-a-chip models have gained attention as replacements for other cell-based assays or animal studies in drug development or toxicological studies. These models aim to provide a more accurate representation of the in vivo situation in form and function; however, no digestive processes have been included in these systems so far. This work describes a miniaturized digestive system based on artificial digestive juices that digest liquid samples in a series of three microreactors. After optimization of the pH value of juices and mixtures, samples leading to fluorescent products were digested to demonstrate enzyme functionality and to determine kinetic parameters.
Effect of endogenous phenoloxidase on protein solubility and digestibility after processing of Tenebrio molitor, Alphitobius diaperinus and Hermetia illucens
Janssen, Renske H. ; Vincken, Jean Paul ; Arts, Nathalie J.G. ; Fogliano, Vincenzo ; Lakemond, Catriona M.M. - \ 2019
Food Research International 121 (2019). - ISSN 0963-9969 - p. 684 - 690.
Black soldier fly - Digestion - Edible insects - Enzymatic browning - Lesser mealworm - Phenoloxidase - Protease - Protein extraction - Solubility - Tyrosinase - Yellow mealworm
Upon extracting soluble proteins from insects as potential food ingredient, endogenous enzymes, such as phenoloxidases, are expected to negatively affect protein properties. The effect of phenoloxidases on solubility and digestibility of proteins was investigated for larvae of Tenebrio molitor, Alphitobius diaperinus and Hermetia illucens. Phenoloxidase inhibition was done using blanching (50 s, 90 °C) before extraction or extracting in presence of sulfite. Similar soluble protein yields and compositions were found without and with sulfite addition, whereas blanching decreased soluble protein yield. Upon in-vitro hydrolysis by pepsin and trypsin, soluble proteins from H. illucens were more digestible than those of T. molitor and A. diaperinus. Phenoloxidase activity during grinding negatively affected in-vitro pepsin hydrolysis. Besides phenoloxidase activity, also endogenous proteases were shown to remain active at pH 8 in extracts containing sulfite and after blanching of larvae. This stresses that protease activity needs to be carefully controlled in the design of insect based ingredients.
Cell wall disruption increases bioavailability of Nannochloropsis gaditana nutrients for juvenile Nile tilapia (Oreochromis niloticus)
Teuling, Emma ; Wierenga, Peter A. ; Agboola, Jeleel O. ; Gruppen, Harry ; Schrama, Johan W. - \ 2019
Aquaculture 499 (2019). - ISSN 0044-8486 - p. 269 - 282.
Digestion - Feed ingredient - Maillard reaction products - Microalgae - Nutritive value
In this study the correlation between the accessibility of nutrients and in vivo nutrient digestibility was tested on the marine microalga Nannochloropsis gaditana in juvenile Nile tilapia (Oreochromis niloticus). It was hypothesized that disrupting the cell walls of microalgae increases the nutrient accessibility and digestibility. N. gaditana biomass was subjected to physical treatments (pasteurization, freezing, freeze drying) or mechanical treatments (bead milling) to influence its cell wall integrity. These treatments resulted in an up to 4 x increase in in vitro accessibility of N. gaditana nutrients, assessed from measurements of leaching and susceptibility to protein hydrolysis. Apparent digestibility coefficients of macronutrients, dry matter, energy, phosphorus and calcium of untreated and treated microalgae biomass were determined in triplicate, at a 30% diet inclusion level. Bead milling the algae led to the highest increase in in vivo digestibility of dry matter, energy, protein, fat, ash and calcium on ingredient level, compared to untreated algae biomass. This includes an increase in apparent digestibility coefficient (ADC) of protein and fat from 62 to 78% and from 50 to 82%, respectively. ADCs of total carbohydrates and of phosphorus were not affected by algal cell disruption. In vivo digestibilities of N. gaditana dry matter, energy, protein, and fat were positively correlated (p <.001; r ≥ 0.91) with the nutrient accessibility of N. gaditana, as estimated with in vitro nutrient leaching analyses. This shows that the in vitro methods used are effective ways to assess the effect of mechanical and physical treatments on in vivo nutrient quality of a single ingredient. The results of this study confirm that nutrient accessibility plays a significant role in the nutrient digestibility of the microalga Nannochloropsis gaditana in Nile tilapia.
Isothiocyanates from Brassica Vegetables-Effects of Processing, Cooking, Mastication, and Digestion
Oliviero, Teresa ; Verkerk, Ruud ; Dekker, Matthijs - \ 2018
Molecular Nutrition & Food Research 62 (2018)18. - ISSN 1613-4125
Digestion - Glucosinolates - Isothiocyanates - Mastication - Processing
The formation of health-beneficial isothiocyanates (ITCs) from glucosinolates depends on a wide variety of plant-intrinsic factors (e.g., concentration of glucosinolates, activity of myrosinase, and specifier proteins) and on a multitude of extrinsic postharvest factors such as the conditions used during industrial processing, domestic preparation, mastication, and digestion. All of these factors contribute to a large variability in the formation of ITCs (and other breakdown products), as well as their intake and absorption upon consumption of Brassica vegetables. This uncertainty in ITC intake and absorption is a barrier for the determination of an optimal Brassica vegetable consumption pattern. In this review, the intrinsic and extrinsic factors that affect the formation, intake, and absorption of ITCs are described according to the most recent findings. The focus of this review includes the hydrolysis reaction mechanisms, the elucidation of the primary factors that play a role in the hydrolysis reaction, the influence of processing and cooking conditions, the effect of chewing, and the roles of the gastric and upper intestinal phases, including the effect of the meal composition (e.g., the effect of other meal compounds present during digestion) on the potential formation of ITCs.
Effect of ingredient particle sizes and dietary viscosity on digestion and faecal waste of striped catfish (Pangasianodon hypophthalmus)
Tran, Tu ; Hien, T.T.T. ; Bosma, R.H. ; Heinsbroek, L.T.N. ; Verreth, J.A.J. ; Schrama, J.W. - \ 2018
Aquaculture Nutrition 24 (2018)3. - ISSN 1353-5773 - p. 961 - 969.
Digestion - Faecal waste - Grinding screen size - Guar gum level - Performance - Striped catfish
The ingredients' particle size and dietary viscosity may alter digestion, performance and faecal waste management of fish. This study aimed to assess the effect of grinding screen sizes of feed ingredients and dietary viscosity on digestibility, faecal waste and performance of striped catfish (Pangasianodon hypophthalmus, Sauvage, 1878). The experiment had a 2 × 3 factorial-design: two feed mesh particle sizes, by grinding ingredient mixtures at two screen sizes (0.8 versus 1.0 mm); and three dietary viscosity levels, created by exchanging carboxymethylcellulose by guar gum (GG) (0, 3 and 6 g of GG/kg of diet). Six diets were assigned to 18 tanks, each connected to three faecal settling tanks. All aquaria were stocked with 20 fish (82 g per fish). After 52 experimental days, dietary viscosity negatively affected both feed digestibility and performance of striped catfish; as a result, the amount of organic matter in the culture system through faeces had increased significantly. The coarse diets significantly increased the digestibility of dry matter and carbohydrate but worsened feed conversion ratio. Increasing dietary viscosity tended to increase the viscosity and moisture content of the faeces, but significantly accelerated the faecal disintegration through the reduction of both faecal recovery and the amount of recovered faeces.
Amino acid absorption in the large intestine of humans and porcine models
Wielen, Nikkie van der; Moughan, Paul J. ; Mensink, Marco - \ 2017
The Journal of Nutrition 147 (2017)8. - ISSN 0022-3166 - p. 1493 - 1498.
Absorption - Amino acid - Digestible Indispensable Amino Acid Score - Digestion - Large intestine
Dietary protein quality has been recognized as a critical issue by international authorities because it can affect important functions of the body. To predict protein quality, the FAO introduced the Digestible Indispensable Amino Acid Score. This score depends on ileal amino acid (AA) digestibility; therefore, the assumption is made that AAs are not absorbed in nutritionally relevant amounts from the large intestine. This article reviews the evidence for this assumption by considering the role of themammalian large intestine in dietary protein and AA digestion and absorption,with particular reference to adult humans. Althoughmost dietary AAs and peptides are absorbed in the small intestine, substantial amounts can enter the large intestine. Nitrogen is absorbed in the large intestine, and a series of animal experiments indicate a potential small degree of AA absorption. In humans, colonocytes have the capacity for AA absorption because AA transporters are present in the large intestine. The absorption of nutritionally relevant amounts of dietary indispensable AAs and peptides in the human large intestine has not been convincingly demonstrated, however.
Dietary electrolyte balance affects growth performance, amylase activity and metabolic response in the meagre (Argyrosomus regius)
Magnoni, Leonardo J. ; Salas-Leiton, Emilio ; Peixoto, Maria João ; Pereira, Luis ; Silva-Brito, Francisca ; Fontinha, Filipa ; Gonçalves, José F.M. ; Wilson, Jonathan M. ; Schrama, Johan W. ; Ozório, Rodrigo O.A. - \ 2017
Comparative Biochemistry and Physiology. B, Biochemistry and Molecular Biology 211 (2017). - ISSN 1096-4959 - p. 8 - 15.
Acid-base balance - Dietary cation-anion difference - Digestion - Energy use - Euryhaline fish
Dietary ion content is known to alter the acid-base balance in freshwater fish. The current study investigated the metabolic impact of acid-base disturbances produced by differences in dietary electrolyte balance (DEB) in the meagre (Argyrosomus regius), an euryhaline species. Changes in fish performance, gastric chyme characteristics, pH and ion concentrations in the bloodstream, digestive enzyme activities and metabolic rates were analyzed in meagre fed ad libitum two experimental diets (DEB 200 or DEB 700mEq/kg) differing in the Na2CO3 content for 69days. Fish fed the DEB 200 diet had 60-66% better growth performance than the DEB 700 group. Meagre consuming the DEB 200 diet were 90-96% more efficient than fish fed the DEB 700 diet at allocating energy from feed into somatic growth. The pH values in blood were significantly lower in the DEB 700 group 2h after feeding when compared to DEB 200, indicating that acid-base balance in meagre was affected by electrolyte balance in diet. Osmolality, and Na+ and K+ concentrations in plasma did not vary with the dietary treatment. Gastric chyme in the DEB 700 group had higher pH values, dry matter, protein and energy contents, but lower lipid content than in the DEB 200 group. Twenty-four hours after feeding, amylase activity was higher in the gastrointestinal tract of DEB 700 group when compared to the DEB 200 group. DEB 700 group had lower routine metabolic (RMR) and standard metabolic (SMR) rates, indicating a decrease in maintenance energy expenditure 48h after feeding the alkaline diet. The current study demonstrates that feeding meagre with an alkaline diet not only causes acid-base imbalance, but also negatively affects digestion and possibly nutrient assimilation, resulting in decreased growth performance.