Digestion Studies Research Articles

Unveiling the potential of Aspergillus terreus SJP02 for zinc remediation and its driving mechanism

In present study, 15 morphologically different fungi isolated from rhizopheric soils of an industrial area were screened for their Zn2+ removal efficiency from aqueous solution. Isolate depicting highest potential was molecularly identified as Aspergillus terreus SJP02. Effect of various process parameters viz. biosorbent dose, contact time, temperature, agitation rate, pH and initial Zn2+ concentration on the fungal sorption capacity were studied. The biosorbent exhibited maximum Zn2+ sorption capacity of 10.7 ± 0.2 mg g− 1 in 60 min. Desorption studies showed 71.46% Zn2+ recovery rate in 120 min with 0.01 N HNO3, indicating efficient metal recovery for reuse and subsequent reutilization of spent mycosorbents. Acid digestion study suggested adsorption being the primary mechanism accounting for 87% Zn2+removal. It was further confirmed by the FE-SEM and EDX analysis. FTIR analysis suggested involvement of amino, hydroxyl, carbonyl, and phosphate functional groups of fungal cell wall in adsorption. The experimental results were in accordance with the tested isotherm and kinetic models, and suggested the role of physical adsorption for Zn2+ removal. Noteworthy, the present study showed better sorption capacity in considerably shorter equilibration time compared to previous reports and advocate potential utilization of A. terreus SJP02 for bioremediation of Zn2+ contaminated wastewater at industrial scale.

Enhanced storage and gastrointestinal stability of spray-dried whey protein emulsions with chitosan and gum Arabic.

Protein-based emulsions are widely utilized for delivering bioactives but suffer from thermodynamic instability, microbial spoilage, and gastrointestinal instability, necessitating enhancement strategies. This study explores the improvement of whey protein isolate (WPI) emulsions through chitosan (CS) coating and spray drying with maltodextrin (MD) or gum Arabic (GA). Canola oil droplets were stabilized with WPI, electrostatic coated with CS, and spray-dried. CS addition significantly increased entrapment efficiency from ∼75-78% to ∼95-98%, correlating with enhanced storage and gastrointestinal stability. During a 2-h gastric digestion study, CS/GA-protected powders demonstrated only 3.6% lipolysis compared to 27.1% for unprotected WPI emulsions, exhibiting superior gastric resistance. Under small intestinal conditions, their digestion rate constant was one-fifth of that for unprotected WPI emulsions. Furthermore, CS/GA-protected powders maintained excellent storage stability for one year. These findings highlight the potential of WPI-based emulsion powders as effective oral delivery systems for lipophilic bioactives, offering improved storage and gastrointestinal stability.

Dual-Mechanism Gastroretentive Tablets with Encapsulated Gentian Root Extract.

Background/Objectives: This study aimed to develop gastroretentive tablets based on mucoadhesive-floating systems with encapsulated gentian (Gentiana lutea, Gentianaceae) root extract to overcome the low bioavailability and short elimination half-life of gentiopicroside, a dominant bioactive compound with systemic effect. The formulation also aimed to promote the local action of the extract in the stomach. Methods: Tablets were obtained by direct compression of sodium bicarbonate (7.5%) and solid lipid microparticles (92.5%), which were obtained with lyophilizing double emulsions. A quality by design (QbD) was employed to evaluate the impact of formulation factors and processing parameters on emulsion viscosity, powder characteristics (moisture content, encapsulation efficiency, flowability), and tablet characteristics (floating lag time, gentiopicroside release, and assessment of dispersibility during in vitro dissolution). Results: The trehalose content and high-shear-homogenization (HSH) time of primary emulsion were critical factors. Trehalose content positively influenced emulsion viscosity, moisture content, floating lag time, encapsulation efficiency, and the release rate of gentiopicroside. HSH time positively affected powder stability and negatively gentiopicroside release. The selected powder had a high gentiopicroside encapsulation efficiency (95.13%), optimal stability, and good flowability. The developed tablets exhibited adequate floating lag time (275 s), mucoadhesive properties, and gentiopicroside biphasic release (29.04% in 45 min; 67.95% in 6 h). Furthermore, the optimal tablet formulation remained stable for 18 months and was primarily digested by duodenal enzymes. Conclusions: Dual-mechanism gastroretentive tablets with encapsulated gentian root extract were successfully developed. The in vitro digestion study demonstrated that the optimal formulation effectively resisted gastric enzymes, ensuring the release of its contents in the small intestine, even in the case of premature gastric evacuation.

Influence of polymer and surfactant-based precipitation inhibitors on supersaturation-driven absorption of Ibrutinib from high-dose lipid-based formulations.

There is a growing pharmaceutical interest in supersaturated lipid-based formulations (Super-LbF) as an innovative strategy to enhance drug loading capacities while simultaneously reducing pill burden. This approach involves increasing the drug concentration above its equilibrium solubility in a lipid solution, achieved through temperature-induced supersaturation or the dissolution of lipophilic ionic salts. However, the physical instability and potential drug precipitation upon the dispersion of LbF remain critical. The focus of this work was to assess the impact of polymer and surfactant as precipitation inhibitors (PIs) in Super-LbF and investigate whether PIs can effectively address the aforementioned challenges. Ibrutinib (Ibr) was selected as a model drug due to its limited solubility and dissolution characteristics. The optimized formulations were characterized with a focus on dispersibility, lipolysis-permeation, and physical stability during storage. The inclusion of PIs in Super-LbF significantly enhanced physical stability by increasing viscosity and reducing the degree of supersaturation through elevated equilibrium solubility. During the dispersion and digestion study, varying levels of transient supersaturation were observed for both Super-LbF and PI-loaded Super-LbF. A noteworthy 2.5 to 3-fold increase in the solubilization ratio was observed for PI-loaded Super-LbF in comparison to Super-LbF without PI. This increase indicates a significant rise in transient drug supersaturation through kinetic and thermodynamic precipitation inhibition mechanisms. Moreover, lipolysis-permeation studies revealed increased flux values with enhanced solubilization, except in the case of Pluronic® F68, which exhibited a reduced free drug concentration near the Permeapad® barrier. Further, the in vivo absorption study confirmed that prolonged supersaturation, facilitated by PIs, contributed to enhancement in drug exposure in rats. PI-loaded Super-LbFs demonstrated a significant improvement (5.1 to 8.9-fold) in the absorption profile compared to Super-LbF without PI (p<0.001). The study results indicate that incorporating PIs into Super-LbF enhances physical stability and maintains transient drug supersaturation under digestive conditions. Overall, this formulation approach shows promise for expanding the application of LbF to enable the successful oral delivery of high-dose regimen drugs.

Green development strategy for efficient quercetin- loaded whey protein complex: Focus on quercetin loading characteristics, component interactions, stability, antioxidant, and in vitro digestive properties.

This study aimed to develop a quercetin-loaded whey protein complex using pH-induced co-assembly for the intestinal-targeted delivery of quercetin. The investigation focused on quercetin loading capacity, formation mechanism, stability, antioxidant activity, and in vitro digestive properties of the complex. The results indicated that the stable complex was obtained at a quercetin-to-protein mass ratio of 1:20, exhibiting a high encapsulation efficiency (96.4%) and loading capacity (4.6%). Interaction studies revealed that quercetin binds to whey protein via hydrophobic interactions and hydrogen bonding, forming an irregular layered structure. Stability analysis demonstrated that the complex possesses high ionic and thermal stability. The antioxidant capacity of quercetin was significantly enhanced by complex encapsulation. In vitro digestion studies showed that the complex could pass through the gastrointestinal tract smoothly and effectively improve the bio-accessibility of quercetin. These findings provide a theoretical basis for the application of whey protein-based quercetin delivery systems in the functional food field.

Impact of Nanoplastics on the Functional Profile of Microalgae Species Used as Food Supplements: Insights from Comparative In Vitro and Ex Vivo Digestion Studies.

The widespread use of plastics in the food industry raises concerns about plastic migration and health risks. The degradation of primary polymers like polystyrene (PS) and polyethylene (PE) can generate nanoplastics (NPs), increasing food biohazard. This study assessed the impact of PS, PE, and PS + PE NPs on Chlorella vulgaris (CV) and Haematococcus pluvialis (HP) before and after in vitro and ex vivo digestion, focusing on particle size, polydispersity index, and surface charge. The modulation of total phenolic content (TPC) induced by NP contamination was also evaluated. Results demonstrated that NP behavior varied with the microalgae medium and persisted postdigestion, posing health risks. Significant size increases were noted for PS + PE in the CV and HP. TPC increased significantly with NP exposure, especially PS + PE. These findings underline the need for regulatory measures to ensure food safety in cases of plastic contamination and to address the behavior and toxicity of NPs.

A Comparative In Vitro Digestion Study of Three Lipid Delivery Systems for Arachidonic and Docosahexaenoic Acids Intended to Be Used for Preterm Infants.

It is well stablished that docosahexaenoic (DHA) and arachidonic (ARA) acids fulfill relevant biological activities, especially in newborns. However, oils containing these fatty acids are not always optimally digestible. To address this, various formulation strategies and lipid delivery systems have been developed. This study compares the following three formulations in an in vitro digestion model to assess bioaccessibility: Enfamil® DHA & ARA (Mead Johnson & Company), an emulsion of FormulaidTM, AquaCelle®, and pasteurized donated human milk, and a previously characterized enzymatic glycerolysis product (GP) of ARA oil and microalgae oil in a 2:1 (w:w) ratio. To evaluate digestibility, parameters such as the percentage of oily phase (OP), micellar phase (MP), free fatty acids, and monoacylglycerols in the digestion product (DP) were considered. Additionally, diacylglycerol content in the MP can be used as an indirect marker of the emulsification capacity of the DP, and consequently, as an indicator of bioaccessibility. The GP demonstrated the highest bioaccessibility, with a DP containing more than 80% MP (<14% OP), rich in free fatty acids (60%) and monoacylglycerols (17%). Furthermore, more than 40% of total diacylglycerols were present in MP, highlighting GPs' potential as a superior delivery system for DHA and ARA in preterm infant formulations.

Effects of Tithonia diversifolia Extract as a Feed Additive on Digestibility and Performance of Hair Lambs.

Animal production requires efficiency, safety and environmental sustainability. Bioactive compounds from tropical plants could modulate ruminal fermentation, providing an alternative method to antibiotic treatment and addressing concerns about antibiotic resistance. In this study, the aim was to determine the effects of Tithonia diversifolia extract (TDE) on performance, intake, digestibility and blood parameters [i.e., glucose, blood urea nitrogen (BUN), aspartate aminotransferase (AST), alanine aminotransferase (ALT)] in crossbreed sheep. The main biocompounds of the TDE include caffeic acid (CA), quercetin (QCT), luteolin (LT) and apigenin (AP). Experiment 1: An in vitro dry matter digestibility (IVDMD) study was conducted to determine the optimal inclusion levels. The IVDM values were 73.09a, 82.03b, 81.01b, 73.20a and 74.51a for the control, 5, 10, 15 and 20 g/kg for the DM treatments, respectively (R-Sq adj = 0.857). The levels of 5 and 10 g were selected for the in vivo experiment. Experiment 2: Twenty-eight male crossbred hair lambs were assigned to four treatments (n = 7): control, 20 mg monensin/day, 5 g TDE/day and 10 g TDE/day groups. No differences in animal performance were observed, including body weight and feed conversion (p > 0.05). The TDE at 10 g/day improved NDF digestibility) (61.32%) and reduced the ruminal acetate to propionate ratio. The total digestible nutrients (TDN) were higher in 10 g TDE treatment with 66.41% and the lowest acetate production (67.82%) (p = 0.042), and propionate production (21.07%) were observed. The TDE were safe at 5 g and 10 g/day for liver function and exhibited lower BUN levels suggesting an improvement in protein metabolism. TDE extract at 10 g/day (TDE10), showed improvements in total tract digestibility of NDF and reduced the ruminal acetate to propionate ratio. However, due to TDE10 reducing the DM intake, the improvements in digestibility and ruminal fermentation were not reflected in growth performance improvements.

Variations in Bovine Milk Proteins and Processing Conditions and Their Effect on Protein Digestibility in Humans: A Review of In Vivo and In Vitro Studies.

Bovine milk proteins account for 10% of the global protein supply, which justifies the importance of thoroughly understanding their digestive processes. Extensive research on digestion is being conducted both in vivo and in vitro. However, interpretations and comparisons across different studies require a thorough understanding of the methodologies used. Both the rate and extent of milk protein digestion can be affected by several intrinsic and extrinsic factors with potential implications for overall digestibility and physiological responses. Among intrinsic factors, the impact of genetic variants in native milk proteins has emerged as a growing research area. To these, further complexity is added by the processing conditions frequently applied to milk prior to consumption. The main aim of this work is to provide an overview of the current knowledge on the impact of variations in milk protein profiles (particularly whey: casein ratio and protein polymorphisms), the treatments applied during processing (pasteurisation, homogenisation) and consumption (temperature changes) on protein digestion. To support the interpretation of the current literature, this manuscript also presents a historical perspective into research in this field and summarizes the protocols that are most frequently used, presently, on in vitro digestion studies.

Vitamin D3 capsulation using maillard reaction complex of sodium caseinate and tragacanth gum

The encapsulation of vitamin D3 (VitD3) using the Maillard reaction complex of sodium caseinate-tragacanth gum (TG) to the production of water-soluble vitamins were studied. Spray drying was used to prepare the complex. Its physicochemical properties, stability, and release characteristics were evaluated. The results showed that containing sodium caseinate- Tragacanth gum (TG) 1 % (w/v) and VitD3 1 % (w/v) had the highest encapsulation efficiency (71 %). The resulting microcapsules showed suitable particle size, strong negative zeta potential, and good stability with spherical morphology. Thermal and spectroscopic analyses showed proper interaction between wall and core components. In vitro, release and simulated digestion studies demonstrated the ability of microcapsules to protect VitD3 under gastric conditions and provide controlled release in the intestine. This encapsulation system shows potential for enriching food with VitD3 and increasing its stability and bioavailability.

The synergistic effect of α-tocopherol and phloretin-loaded nanoemulsions on improvement of the stability, antioxidant, and tyrosinase inhibitory potentiality.

The purpose of this study was to prepare and evaluate the formulation of nanoemulsions (NEs) to encapsulate phloretin (PT) to improve its stability, antioxidant, and tyrosinase inhibitory competence. The aim of this study was to improve the stability, antioxidant, and tyrosinase inhibitory effects of PT via NEs. The formulations were prepared using low energy emulsification method for PT-VE-NEs, α-tocopherol (Vitamin E) and medium chain triglycerides (MCT) were used as the oil phase, and Tween 60 was used as the emulsifier and PEG-400 as the co-emulsifier. The droplet size and zeta potential of oil-in-water NEs were evaluated using dynamic light scattering. The PT-VE-NEs were also characterized by transmission electron microscopy and Fourier transform infrared spectroscopy. The mean droplet diameter was 14.85±0.14nm, with a zeta potential of -2.47±0.51mV. Fourier transform infrared spectroscopy revealed the formation of molecular interactions in the NEs formulations. PT-VE-NEs size was maintained the same during the in vitro digestion study. The particle size of PT-VE-NE remained stable during in vitro digestion. The addition of VE significantly improved the antioxidant, tyrosinase inhibitory effects, as well as thelion and physical stability of PT-VE-NE. The results revealed that NEs is a promising strategy to improve the functionality and stability of PT and VE. PT-VE-NEs will be applied for the preservation of fruits.

Microplastics interactions and transformations during in vitro digestion with milk

Despite increasing awareness of microplastic contamination in food, the specific interactions and transformations of microplastics during digestion remain poorly understood. The study investigates the behavior of microplastics during in vitro digestion processes and their interaction with components of milk. The in vitro digestion studies are conducted to study the changes in microplastics in simulated digestive fluids, with and without milk. The study revealed that microplastics undergo significant changes in size, surface morphology, and chemical properties when subjected to digestion with and without milk. Notably, microplastics digested with milk exhibited a 15–25% increase in aggregation due to protein corona formation, enhancing their potential for interactions within biological systems. FTIR analysis revealed the formation of OH and CO groups in digested microplastics, indicating hydrolysis and structural changes. The stronger peaks in the 1630–1650 cm−1 range suggest significant adsorption of milk proteins, highlighting the complex interactions during digestion. Additionally, the chemicals and additives leached from microplastics into digesta raising the concerns about their potential health effects. The study emphasizes the necessity for additional research and regulatory measures to address the risks associated with microplastic contamination in food.

Chemical reaction engineering of nutritional phenomena in the human body

Unlike many accomplished fields, human nutrition lacks the support of engineering science. Here, the aspects of food processing in the gastro-intestinal (GI) tract are reviewed, highlighting the experimental chemical reaction engineering (CRE) approach to digestion studies in particular. As a first look at human nutrition in terms of conservation laws, the differential forms of mass and energy balances are presented, emphasizing the chemical and biochemical reaction rates of generation and consumption and the heats associated with these reactions, respectively. These rates and the heats should be very meaningful for understanding the dynamics of nutrition within the body, though they remain unknown. Without solving the differential equations, global integrations of the mass balances within each organ, up to the organ boundary, can create control volumes for gaining new insights, such as the transient multicomponent nature of the stomach “reactor” emptying. Global integration within the human body to the boundaries of the entire GI tract, from the mouth to anus, finds the GI tract to be a “pipe outside the body.” This has revealed interesting aspects, highlighting the human body as a “molecular machine.” It is envisaged that the terms outlined here ought to be established in the future to improve human nutrition.

Do cooking techniques influence copper bioaccesibility in foods after in vitro digestion/fermentation in adults and children?

Cu is essential for the growth and organism health. Classically, its available fraction has been studied by in vitro digestion studies as a measure of bioaccessibility of Cu (Cu-BA). In this work we applied a novel in vitro digestion/fermentation method to multiple foods subjected to different home cooking techniques (raw form vs. frying, roasting, toasting, boiling and grilling) by metabolization with faecal inoculate from healthy adults (HE-AD), and healthy children (HE-CH) and sick children (children with gluten related disorders, GRD-CH; children with obesity, OB-CH; and children with allergy/intolerance to cow’s milk proteins, AICM-CH). In raw and cooked foods the bioaccessibility of Cu in the small intestine (Cu-BASI) was higher vs. that in the Cu bioaccessibility in the large intestine (Cu-BALI) (30.8 ± 15.4 and 28.2 ± 14.7 vs. 18.4 ± 21.2 and 22.8 ± 22.1 %, respectively; p < 0.001). Total Cu-BA in cooked foods (51.0 ± 24.4 %) was higher than that in raw foods (49.0 ± 25.1 %). In cereals, total Cu-BA was higher in the raw form, as well as in whole grains and those with gluten (p < 0.05). In vegetables, the most drastic cooking techniques (roasting and frying) show higher values of total Cu-BA compared to raw form and boiling. The Cu-BALI in HE-CH (37.7 ± 23.7 %) is higher than that determined in HE-AD (14.1 ± 18.5 %) and sick children (GRD-CH: 14.6 ± 19.8; OB-CH: 15.5 ± 17.8; and AICM-CH: 26.9 ± 19.3 %; p < 0.001). In conclusion, cooking techniques influence Cu-BA depending on the food group. Total Cu-BA, as well as that determined in the large and small intestine varied according to the category, group and specific foods, which is related to their different composition and species of the element. In healthy children, total Cu-BALI is higher than in adults and celiac, obese and allergic children probably due to growth requirements and specific microbiota.

Constructing stable emulsion gel from gelatin and sodium alginate as pork fat substitute: Emphasis on lipid digestion in vitro

This study aimed to develop a gelatin-sodium alginate (G-SA) emulsion gel that can efficiently hold corn oil, as a substitute for pork fat while controlling the digestive behaviors of lipids in vitro. UV, fluorescence, and circular dichroism spectra and surface hydrophobicity measurements of the G-SA mixtures indicated that gelatin and sodium alginate primarily form aggregates through hydrogen bonds and hydrophobic interactions, and the optimum gelatin-to-sodium alginate w/w ratio was identified as 1.9. The final emulsion gel contained 3.15% gelatin and 1.65% sodium alginate (w/w) with a corn oil content of 40% (w/w). G-SA emulsion gel had a higher proportion of polyunsaturated fatty acids (PUFAs, 53.95 g/100 g) than pork fat (15.17 g/100 g). In addition, the G-SA emulsion gel exhibited stable viscoelastic properties without storage and loss moduli changes at increasing shear rates. The G-SA emulsion gel had a higher melting temperature (42.63 °C) than pork fat (35.07 °C). In vitro digestion studies showed that corn oil had a higher free fatty acid release (40.32%) compared to the G-SA emulsion gel (12.66%) and pork fat (8.53%) (P<0.05), indicating that the digestibility of corn oil was reduced in the G-SA emulsion gel. Calcein release experiments revealed that G-SA emulsion gel released the least amount of calcein (P<0.05) during digestion at a slow rate. The G-SA emulsion gel, similar to pork fat, contained evenly distributed digestive particles encapsulating corn oil after in vitro gastric digestion, with the smallest particle size among the treatments. After the in vitro small intestinal digestion phase, the G-SA emulsion gel maintained small droplet sizes with bridging flocculation. The in vitro digesta of the G-SA emulsion gel contained a significantly higher proportion of PUFAs compared to pork fat (P<0.05). Consequently, the G-SA emulsion gel can be a potential substitute for pork fat, offering higher proportions of PUFAs, lower fat content, and controlled lipid digestion with reduced lipid digestibility.

Effects of chicken slurry inclusion on apparent total tract macronutrient digestibility, palatability, and fecal characteristics, microbiota, and metabolites of healthy adult dogs.

"Premium" pet foods are often formulated with meat slurries. Meat slurries are believed to be of higher quality than rendered meals, but inadequate research has been performed to test how their inclusion affects palatability, digestibility, or indicators of gastrointestinal health. Therefore, the objectives of this study were to determine how chicken slurry inclusion affected the palatability and apparent total tract digestibility (ATTD) of dog foods and to assess their effects on the fecal characteristics, metabolites, and microbiota of dogs. A replicated 3 × 3 Latin square design digestibility study was conducted using 9 healthy adult dogs (age = 5.44 ± 0.53 yr) to test diets containing 0% (control; CON), 8% (low inclusion; LOW), and 16% (high inclusion; HIGH) chicken slurry. The experiment comprised three 21-d experimental periods (14 d of adaptation, 5 d of total fecal collection (used for ATTD calculations), and 2 d of blood collection). On the first day of fecal collections, one fresh sample was collected for measurement of pH, dry matter (DM) content, fermentative metabolite concentrations, and microbiota populations. A 2-d palatability study (n = 20 dogs) was also conducted to compare CON vs. HIGH. Data were analyzed statistically by Mixed Models using SAS 9.4, with P < 0.05 being significant. In the palatability study, dogs were shown to prefer (P < 0.05) the HIGH diet by a ratio of 2:1. In the digestibility study, fecal output, scores, pH, and DM percentage were not different among diets. The ATTD of protein was higher (P < 0.05) for the HIGH diet (84.6%) than for the LOW (82.7%) or CON (82.6%) diets. The ATTD of other nutrients and energy were not different among diets (all over 80%). Fecal propionate, butyrate, and total short-chain fatty acid concentrations were higher (P < 0.05) in dogs fed the LOW diet (122.0, 67.4, and 408.2 μmol/g, respectively) than those fed the HIGH diet (89.0, 46.9, and 338.2 μmol/g, respectively). The other fecal metabolites (acetate, branched-chain fatty acids, ammonia, phenol, and indole) were not different among treatments. Few changes to the fecal microbiota were noted. However, the relative abundance of fecal Fusobacterium was higher (P < 0.05) in dogs fed the CON diet than those fed the HIGH diet (25.7% vs. 20.0% relative abundance). In summary, chicken slurry inclusion improved palatability but had minimal effects on nutrient digestibility and fecal characteristics, metabolites, and microbiota.

Indole-3-Acetic Acid Esterified with Waxy, Normal, and High-Amylose Maize Starches: Comparative Study on Colon-Targeted Delivery and Intestinal Health Impact.

Background: Accumulating research suggests that metabolites produced by gut microbiota are essential for maintaining a balanced gut and immune system. Indole-3-acetic acid (IAA), one of tryptophan metabolites from gut microbiota, is critical for gut health through mechanisms such as activating aryl hydrocarbon receptor. Delivery of IAA to colon is beneficial for treatment of gastrointestinal diseases, and one promising strategy is IAA esterified starch, which is digested by gut microbes in colon and releases loaded IAA. Amylose content is a key structural characteristic that controls the physicochemical properties and digestibility of starch. In the current study, IAA was esterified with three typical starches with distinct amylose content to obtain indolyl acetylated waxy maize starch (WMSIAA), indolyl acetylated normal maize starch (NMSIAA), and indolyl acetylated high-amylose maize starch (HAMSIAA). The study comparatively analyzed their respective physicochemical properties, how they behave under in vitro digestion conditions, their ability to deliver IAA directly to the colon, and their effects on the properties of the gut microbiota. The new characteristic peak of 1H NMR at 10.83 ppm, as well as the new characteristic peak of FTIR spectra at 1729 cm-1, represented the successful esterification of IAA on starch backbone. The following in vitro digestion study further revealed that treatment with indolyl acetylation significantly elevated the resistant starch content in the starch samples. In vivo experimental results demonstrated that WMSIAA exhibited the most significant increase in IAA levels in the stomach, whereas HAMSIAA and NMSIAA demonstrated the most remarkable increases in IAA levels in the small intestine and colon, respectively. The elevated IAA levels in the colon are conducive to promoting the growth of beneficial intestinal bacteria and significantly alleviating DSS-induced colitis. This research presents innovative insights and options for the advancement of colon-specific drug delivery systems aimed at preventing and curing gastrointestinal disorders.

Quantitative 13C-IS pyrolysis-GC-MS lignin analysis: Overcoming matrix effects in animal feed and faeces

Recently, a pyrolysis-GC-MS methodology for specific lignin quantification and structural characterisation was developed, relying on the use of uniformly 13C-labeled polymeric lignin isolate as internal standard (IS). The 13C-IS py-GC-MS method has been validated for grasses, woods, and applied in various showcases. To study the fate of lignin in animals, this method still requires careful validation in animal feeds and, especially complex faecal samples, hence the aim of this work. Hereto, faecal material was collected from pigs fed with wheat straw as lignin source and subjected to the py-GC-MS analytical platform for thorough examination of IS pyrolysis behaviour in terms of response and structural features. Next, 13C-ISpy-lignin contents and corrected Klason lignin contents were compared. Most importantly, we revealed that pyrolysis behaviour of 13C-IS lignin and 12C-sample lignin was differently affected in the faecal matrix, resulting in the ultimate underestimation of 13C-ISpy-lignin contents. In-depth examination and evaluation of matrix constituents showed that predominantly matrix ash was responsible for the effects observed. We further demonstrated that said matrix effects can be overcome by water extraction of the samples prior to analysis. Our validation and approach extend the use of the specific 13C-IS py-GC-MS methodology for accurate quantitative lignin analysis to biomass samples with complex matrices like pig faeces, and now call for application in future digestibility studies.

Starch Kinetics, Cooking Quality and Phytochemical Composition of Geographical Indication (GI) Tagged Rice of Kerala

Geographical Indication (GI) tagged traditional rice of Kerala namely the red pigmented Palakkadan Matta and non-pigmented aromatic rice - Wayanadan Gandhakasala and Wayanadan Jeerakasala are well known for their cooking and eating quality, but are under utilized for their nutritional significance. The objective of this study was to classify these varieties based on their starch digestibility, biochemical composition and cooking characteristics. Results indicated significant (p &lt; 0.05) variation among rice varieties for all the parameters evaluated. In vitro starch digestibility studies found significantly low glycemic index (&lt; 68) but higher RS content for Wayanadan Gandhakasala and Chettadi. Aromatic varieties had lower cooking time (&lt; 25 min) than Palakkadan Matta varieties. High water uptake ratio and elongation ratio was also noted for Wayanadan Gandhakasala. Total phenolic content correlated positively to total flavonoid content. Over all, Palakkadan Matta varieties had significantly higher free phenolic, free flavonoid and total flavonoid content than non pigmented varieties. The study indicates that these GI tagged traditional rice varieties can thus be utilised in the functional food industry based on their intermediate glycemic index, desirable cooking qualities and the presence of beneficial bioactive components.

Microfluidization outperforms homogenization: Optimizing stability and bioaccessibility in krill oil emulsions

AbstractThis research presents a rigorous comparative analysis of high‐pressure homogenization (HPH) and microfluidization (MF) for the production of krill oil (KO) emulsions, scrutinizing their impact on oxidative stability, bioaccessibility, and the behavior under in vitro simulated digestion. Our findings revealed that MF emulsions possessed a distinct advantage, with a droplet size and distribution that promoted exceptional oxidative stability, evidenced by a sustained reduction in oxidative markers and enhanced retention of bioactive components, including EPA and DHA, and the potent antioxidant astaxanthin. In contrast, HPH yielded larger and less uniform particles, correlating with diminished stability. The in vitro digestion studies underscored the superior bioaccessibility of MF emulsions, with a pronounced release of free fatty acids during the intestinal phase, indicative of an optimized digestion and absorption process due to the smaller droplet size of the emulsions. The study's insights advocate for the adoption of microfluidization in the food industry for the development of advanced delivery systems for n‐3 fatty acids, particularly in the context of KO‐based products. The technique shows promise in enhancing the quality, stability, and bioavailability of these products, which are rich in health‐promoting lipids. The microfluidization technique emerges as a promising avenue for the fortification of a diverse range of commercial food, beverage, and pharmaceutical products with lipids that contribute to health and wellness.