D-Tagatose Is a Promising Sweetener to Control Glycaemia: A New Functional Food

Characterization of a tagatose 4-epimerase and optimizing its expression for efficient D-tagatose bioconversion from fructose

D-Tagatose is a promising functional sweetener due to its safety profile and versatile physiological effects. Recently, the bioconversion of D-tagatose from cost-effective natural resources has gained increasing attention. In this study, the hypothetical protein DRJ43_04605 from Thermoprotei archaeon, abbreviated as DRJ43-T4Ease, was identified as a tagatose 4-epimerase capable of efficiently converting d-fructose into D-tagatose. DRJ43-T4Ease exhibited optimal specific activity of 0.79 U/mg at pH 7.5 and 90 °C in the presence of 1 mM Ni2+. The denaturation temperature (Tm) of the enzyme was determined to be 105.9 °C, with a half-life of 7.19, 6.56, and 4.84 h at 85, 90, and 95 °C, respectively. The kinetic parameters for d-fructose conversion, including Km, kcat, and kcat/Km, were calculated to be 51.86 mM, 127.22 min-1, and 2.45 mM-1 min-1, respectively. Furthermore, the expression of DRJ43-T4Ease in E. coli was optimized by engineering the translation initiation sequence. The engineered strain EcDRJ43-T4Ease-M1 achieved a volume activity of 98.4 U/L through shake-flask fermentation and a conversion efficiency of 17.2 % using 100 g/L d-fructose as the substrate. This study demonstrates the potential for D-tagatose production from d-fructose via whole-cell bioconversion, providing a promising approach for the industrial-scale production of this valuable sweetener.

Impact of Tagatose on Physicochemical, Nutritional, and In Vitro Digestive Properties of Toast Bread

It is more attractive to develop effective strategies to reduce sugar intake without compromising food quality with the rising prevalence of obesity and diabetes around the world. Due to its high cost, tagatose has not been widely adopted as a sucrose substitute in toast bread. In the present research, five types of toast containing different proportions (0%, 4%, 8%, 12%, and 16%) of tagatose with sweetness similar to that of sucrose were prepared. The effects of tagatose on microstructural, textural, physicochemical, nutritional, and sensory properties and in vitro digestion were evaluated using techniques such as Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), rheological test, textural profile assay (TPA), and gas chromatography-mass spectrometry (GC-MS) analysis. The results indicated that after the substitution of tagatose for sucrose, the water-holding capacities of the dough were increased, whereas the specific volume of toast was decreased from 4.74 to 3.01 mL/g (p < 0.05), and the acidity of toast was increased from 1.92 to 2.69°T (p < 0.05). The content of flavor substances, especially alcohols, in the toast was significantly increased by the addition of tagatose. However, the glycemic index (GI) of toast was decreased from 94.39 to 67.96 (p < 0.05). Overall, the addition of 12% or more tagatose will significantly reduce the GI of toasted bread and enrich the flavor, but it will lead to a decrease in specific volume and an increase in acidity. Tagatose is a promising alternative sweetener with low calorie.

Screening and characterization of thermostable xylose isomerase from Rhodothermus marinus for erythrose production from one-carbon source

Four-carbon (C4) sugars, which rarely exist in nature, usually have various biological functions and serve as building units for pharmaceutical agents. For example, erythrose possesses various pharmacological activities. Although several iso/epimerases have a catalytic function on C5/C6 sugars, only a few studies have demonstrated the enzymatic iso/epimerization of C4 sugars. In this work, we presented a xylose isomerase from Rhodothermus marinus possessing isomerization activity toward C4 l-erythrulose. This enzyme showed higher affinity and catalytic efficiency toward l-erythrulose than d-fructose and d-xylulose. Its specific activity reached 24.2 U/mg under optimal reaction conditions, and its half-life was over 8 days at 50 ℃. Demonstration of this enzyme under 833 mM of L-erythrulose gave 130 mM L-erythrose with a conversion yield of 15.6 %. On the basis of this beneficial enzyme, we further designed a multienzyme system and presented a one-pot cascade process for the synthesis of l-erythrose from low-cost, one-carbon formaldehyde (FALD) as the sole feedstock. Given that FALD can be derived from CO2 electrocatalysis or methanol oxidization, l-erythrose synthesis can be realized from methanol and even CO2. l-erythrose can further function as feedstock for synthesizing other high-carbon sugars by coupling enzymatic aldol condensation and reduction reactions.

Enabling Stable Recycling of L-Arabinose Isomerase Through Whole-Cell Immobilization for Efficient and Cost-Effective D-Tagatose Production

D-tagatose is a functional sweetener with glucose-regulating and prebiotic properties, but its bioproduction from D-galactose faces many limitations, particularly the high production costs. In particular, the current biosynthesis of D-tagatose suffers from thermal instability and the substrate selectivity issues of L-arabinose isomerase (L-AI) required to convert D-galactose into D-tagatose. In this study, recombinant Escherichia coli BW25113/pQE-80L-araAF118M/F279I expressing double mutant L-AI was immobilized to enhance its stability and reusability. The optimal conditions for whole-cell catalysis were 60 °C, pH 6.5, 5 mM Mn2+, and 20 h, with a yield of 55.2 g/L of D-tagatose. Immobilization with 3% sodium alginate and 2% CaCl2 retained 90% of the production efficiency displayed by free cells. Notably, the immobilized cells exhibited enhanced heat resistance (60-70 °C) and operational stability, retaining 76% activity after five cycles. The D-tagatose production was further increased to 129.43 g/L by increasing the substrate concentration to 250 g/L. Compared to free cells, immobilized cells retained 83.6% of the initial yield up to 10 batches. This study presents a cost-effective and sustainable method for the production of D-tagatose using optimized whole-cell catalysis through immobilization, which paves the way to solve industrial challenges such as thermal instability and low substrate efficiency.

Biosynthesis of a healthy natural sugar D-tagatose: advances and opportunities

D-tagatose is a natural low-calorie rare sugar with nearly the same sweet taste as sucrose. It has nutritional and functional properties of great interest for health, such as anti-diabetes, anti-caries, anti-atherosclerosis, anti-hyperlipidemia, anti-aging, improvement of intestinal microflora, etc. The production of D-tagatose from D-galactose catalyzed by an alkali suffers from limited supplies of costly feedstock (i.e., lactose) and high manufacturing costs due to harsh reaction conditions, costly separation, as well as severe degradation and pollution. In this review, we briefly present the properties of D-tagatose and its physiological effects, review the recent advances in the biosynthesis of D-tagatose from inexpensive and abundant glucans (e.g., starch) and their derivatives (e.g., D-glucose and D-fructose) and from lactose, including both academic literature and industrial patents, as well as discuss its future challenges and opportunities. The biosynthesis of D-tagatose can be catalyzed by four types of biocatalysts: enzymes, whole-cells, microbial fermentation, and in vitro multi-enzyme molecular machines. The biomanufacturing of starchy D-tagatose catalyzed by multi-enzyme molecular machines could be the most promising approach because it not only makes D-tagatose from ample starch but also surpasses the equilibria of monosaccharide isomerization reactions (e.g., D-fructose-to-D-tagatose, D-galactose-to-D-tagatose). D-tagatose as a filler for a variety of food and drinks or a key component mixed with other sweeteners would become a predominant starch-derived sweetener and partially replace high-fructose corn sirup in the future.

The use of isomerases and epimerases for the production of the functional sugars mannose, allulose and tagatose from Fructose

Fructose, a common monosaccharide in nature extensively utilized in the food industry, poses a risk of elevated chronic disease incidence with excessive consumption. The global movement for a healthier living has sparked a quest for sugar reduction in foodstuff. The growing concern regarding the adverse impact of excessive sugar consumption on public health has led to significant interest in investigating healthier sugar alternatives. Research efforts have refocused on converting fructose into high-value, reduced-calorie functional sugars. Fructose can undergo direct conversion into three such sugars-mannose, allulose, and tagatose-via a streamlined bioconversion process. Allulose and tagatose, epimers of fructose, are derivable directly from fructose through C-3 and C-4 epimerization processes, whereas mannose, the aldose isomer of fructose, can be synthesized via isomerization pathways. This article aims to present recent advancements in the physiological functions, production methods, and applications of functional sugars derived from fructose. Particularly, it focuses on the bioproduction of mannose, allulose, and tagatose from fructose, encompassing discussions on the recent progress in the related isomerases and epimerases, such as mannose isomerase/lyxose isomerase, ketose 3-epimerase, and tagatose 4-epimerase. This review will provide a fresh perspective on the high-value biological utilization of fructose resources.

Stability of sugars in yogurts with simple and complex microbial composition during refrigerated shelf life

There is a large and growing market for natural sweeteners with low glycemic index. Of particular interest are the "rare sugars" (e.g., d-tagatose). Rare sugars could be applied in dairy foods, such as yogurt, as sucrose replacements. Yogurt contains live and active cultures and, consequently, their enzymes. These enzymes include those capable of sugar hydrolysis or isomerization, which could undermine the nutritional benefits of rare sugars. The purpose of this research was to evaluate sugar stability and influence of added sugars during storage of commercial nonfat Greek yogurts having simple and complex microbial compositions. Two commercial nonfat Greek yogurt products with different bacterial profiles (simple: Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus; complex: S. thermophilus, L. delbrueckii ssp. bulgaricus, Bifidobacterium lactis, Lactobacillus acidophilus, and Lacticaseibacillus rhamnosus) were supplemented with sugars (fructose, galactose, glucose, lactose, sucrose, and d-tagatose) at 10% (wt/wt) in duplicate and sampled every 2 wk. Individual sugar concentrations and lactic acid were measured using a combination of enzyme kits (Megazyme) and high-performance liquid chromatography. Sugar (lactose, glucose, galactose) and lactic acid isomer concentrations were significantly different between the 2 commercial products, but neither product changed significantly during refrigerated storage. Each added sugar (10%) was stable throughout the 6-wk refrigerated storage period. The pH of all yogurts decreased slightly (-0.1 pH) during storage, but with no corresponding change in lactic acid concentration. These results provide foundational data on the stability of various sugars in cultured dairy products throughout refrigerated shelf life.

Oral Transfer of Anti-Aging Substances: Key Chemical Found in Reproductive Caste of Termites

With the rapid increase in global population aging, the incidence and mortality rates of age-related diseases are rising, becoming a worldwide issue. Therefore, researching and discovering natural compounds with anti-aging properties is crucial. Social insects such as termites exhibit significant differences in lifespan between reproductive and non-reproductive castes. Reproductive castes are exclusively fed by worker termites through trophallaxis, providing a convenient model for the discovery of natural anti-aging compounds. This thesis systematically investigates the trophallactic fluid among different caste members of termite Reticulitermes labralis. A total of 1028 metabolites were identified in the trophallactic fluid, seven of which have been validated in the KEGG database to possess anti-aging functions. This indicates that the trophallactic fluid of termites indeed contains natural compounds that promote longevity. Using the "fishing method", we successfully screened out potential life-extending compounds, including IDA (trans-3-indoleacrylic acid). Preliminary experimental results showed that IDA influences lifespan by modulating the IIS (insulin/insulin-like growth factor signaling) pathway and the RAS pathway. Notably, the modulation of the IIS pathway by IDA does not require the involvement of foxoa. Our research findings suggest that the extended lifespan of reproductive termites is diet-related and that the lifespan-extending effects of these nutritionally regulated natural compounds are conserved across different taxa.

Construction of a multienzyme cascade reaction system and its application in D-tagatose biosynthesis

D-tagatose, a low-calorie rare sugar, has significant potential in food, medicine, cosmetics, and other industries owing to its high application value and market potential. In this study, Escherichia coli BL21 was used as the starting strain to express the β-galactosidase (β-Gal) gene-BgaB-derived from Bacillus stearothermophilus and the L-arabinose isomerase (L-AI) gene-araA-derived from Thermus sp., yielding the genetically engineered strains E. coli BL21-pET28a-BgaB and E. coli BL21-pET28a-araA. These strains synthesized D-tagatose using β-Gal and L-AI with a conversion rate of 23.73%. Based on this, we constructed a multienzyme cascade pathway comprising β-Gal, L-AI, glucose isomerase (GI), fructose kinase (FK), D-tagatose-bisphosphate aldolase (GatZ), polyphosphate kinase (PPK), and phosphatase (PGP), further enhancing D-tagatose biosynthesis. This multienzyme approach improved the conversion of the intermediate product D-glucose to D-tagatose by 3.84% compared with the dual-enzyme system. Thus, our study provides a theoretical basis and technical support for the industrial production of D-tagatose.

Effects of D-Tagatose on Cariogenic Risk: A Systematic Review of Randomized Clinical Trials

Dental caries remains a prevalent chronic disease driven by dysbiosis in the oral biofilm, with Streptococcus mutans playing a central role in its pathogenesis.

OBJECTIVE

This study aimed to assess the effect of D-tagatose on cariogenic risk by analyzing randomized clinical trials (RCTs).

METHODS

A systematic literature review was conducted targeting RCTs published up to 2024 in eight databases and two gray literature sources. The search strategy utilized Medical Subject Headings (MeSHs) and relevant keywords combined via Boolean operators using the query "Tagatose OR D-tagatose AND Dental Caries". Eligible studies must evaluate the impact of D-tagatose on cariogenic risk, as indicated by reductions in colony-forming units (CFUs) and improvements in salivary pH levels in treatment groups.

RESULTS

From 1139 retrieved records, three studies met the inclusion criteria. These studies consistently demonstrated significant reductions in CFU counts and improvements in salivary pH levels in groups treated with D-tagatose compared to controls using other non-caloric sweeteners or placebos (p < 0.01). However, the quality of the evidence was heterogeneous, with certain methodological concerns.

CONCLUSIONS

Although the findings suggest potential benefits of D-tagatose in reducing cariogenic risk, limitations such as small sample sizes and variability in study methodologies warrant caution. Further robust investigations are needed to substantiate these promising results and support the integration of D-tagatose into oral care formulations aimed at reducing cariogenic risk.

Artificial Cascade Transformation Biosystem for One-Pot Biomanufacturing of Odd-Numbered Neoagarooligosaccharides and d-Tagatose through Wiser Agarose Utilization

The application of agarose oligosaccharides has garnered great attention, with their biological activities varying among different structures. However, it still meets a great bottleneck for the targeted production of odd-numbered neoagarooligosaccharides (NAOSs), such as neoagarotriose (NA3), due to the lack of one-step hydrolases. In this work, the α-agarase AgaA33 and β-galactosidase BgaD were synergistically used to prepare NA3 with agarose as a substrate. Additionally, an l-arabinose isomerase CaLAI from Clostridium acetobutylicum was characterized to valorize low-value byproducts (d-galactose) by forming d-tagatose, which exhibited good thermal stability without the need for additional metal ions. Under the optimal reaction conditions, the production of NA3 and d-galactose catalyzed by these three enzymes was 0.40 and 0.15 g/L, respectively. The artificial three-enzyme-based cascade transformation system not only achieved the highest production of NA3 until now but also allowed for the valorization of d-galactose, providing a wiser application route for agarose utilization.

[Effects of D-tagatose, Stevia and Sucrose on pH and oral bacterial activity in dentistry students. A randomized controlled trial]

Introduction

Background: stevia and D-tagatose have shown a reduction in total calorie and carbohydrate intake as a substitute for sucrose, demonstrating a stabilizing effect on pH and bacterial proliferation. Objective: to evaluate the effect of D-tagatose, stevia and sucrose on salivary pH and bacterial activity in odontology students. Methodology: a controlled study of parallel and randomized groups with a single blind, whose sample considered three groups subjected to a mouthwash of D-tagatose (n = 10), stevia (n = 10) and sucrose (n = 10). These solutions were administered over 1 minute in a single 6.4 % concentrated dose. Data collection and analysis considered the recording of salivary pH 5 min before exposure to the sweetener, immediately after expulsion of the mouthwash and 15 min later, 30 min, 45 min and 48 hours. The counting of the final number of colony-forming units per mL (CFU/mL) was counted using the salivary samples obtained immediately after exposure of the sweetener together with the sample obtained 30 minutes later, with the cultures performed on agar plates. Results: D-tagatose, stevia and sucrose presented significant differences in total CFU/mL at 30 minutes (p < 0.001), while salivary pH showed significant differences at 48 hours after administration (p < 0.001). Conclusion: D-tagatose, stevia and sucrose present significant differences in total CFU/mL and salivary pH, these findings being a possible indication of a partial inhibitory effect on bacterial metabolism.

Food Waste Biotransformation into Food Ingredients: A Brief Overview of Challenges and Opportunities

In today's global context, challenges persist in preventing agri-food waste due to factors like limited consumer awareness and improper food-handling practices throughout the entire farm-to-fork continuum. Introducing a forward-thinking solution, the upcycling of renewable feedstock materials (i.e., agri-food waste and by-products) into value-added ingredients presents an opportunity for a more sustainable and circular food value chain. While multi-product cascade biorefining schemes show promise due to their greater techno-economic viability, several biotechnological hurdles remain to be overcome at many levels. This mini-review provides a succinct overview of the biotechnological and societal challenges requiring attention while highlighting valuable food-grade compounds derived from biotransformation processes. These bio-based ingredients include organic acids, phenolic compounds, bioactive peptides, and sugars and offer diverse applications as antioxidants, preservatives, flavorings, sweeteners, or prebiotics in foodstuffs and other consumer goods. Therefore, these upcycled products emerge as a sustainable alternative to certain potentially harmful artificial food additives that are still in use or have already been banned from the industry.

L-arabinose isomerase from Lactobacillus fermentum C6: Enzymatic characteristics and its recombinant Bacillus subtilis whole cells achieving a significantly increased production of D-tagatose

L-arabinose isomerase (L-AI) is a functional enzyme for the isomerizing of D-galactose to produce D-tagatose. In this study, L-AI-C6-encoding gene from the probiotic Lactobacillus fermentum C6 was cloned and expressed in Bacillus subtilis WB600 for investigating enzymatic characteristics and bioconverting D-tagatose by means of whole-cell catalysis. Results showed that the engineered B. subtilis WB600-pMA5-LAI achieved a maximum specific activity of L-AI-C6 (232.65 ± 15.54 U/mg protein) under cultivation in LB medium at 28 °C for 40 h. The recombinant L-AI-C6 was purified, and enzymatic characteristics test showed its optimum reaction temperature and pH at 60 °C and 8.0, respectively. In addition, L-AI-C6 exhibited good stability within the pH range of 5.5-9.0. By using B. subtilis WB600-pMA5-LAI cells as whole-cell catalyst, the highest D-tagatose yield reached 42.91 ± 0.28 % with D-galactose as substrate, which was 2.41 times that of L. fermentum C6 (17.79 ± 0.11 %). This suggested that the cloning and heterologous expression of L-AI-C6 was an effective strategy for improving D-tagatose conversion by whole-cell catalysis. In brief, the present study demonstrated that the reaction temperature, pH, and stability of L-AI-C6 from L. fermentum C6 meet the demands of industrial application, and the constructed B. subtilis WB600-pMA5-LAI shows promising potential for the whole-cell biotransformation of D-tagatose.

How probiotics, prebiotics, synbiotics, and postbiotics prevent dental caries: an oral microbiota perspective

Dental caries, a highly prevalent oral disease, impacts a significant portion of the global population. Conventional approaches that indiscriminately eradicate microbes disrupt the natural equilibrium of the oral microbiota. In contrast, biointervention strategies aim to restore this balance by introducing beneficial microorganisms or inhibiting cariogenic ones. Over the past three decades, microbial preparations have garnered considerable attention in dental research for the prevention and treatment of dental caries. However, unlike related pathologies in the gastrointestinal, vaginal, and respiratory tracts, dental caries occurs on hard tissues such as tooth enamel and is closely associated with localized acid overproduction facilitated by cariogenic biofilms. Therefore, it is insufficient to rely solely on previous mechanisms to delineate the role of microbial preparations in the oral cavity. A more comprehensive perspective should involve considering the concepts of cariogenic biofilms. This review elucidates the latest research progress, mechanisms of action, challenges, and future research directions regarding probiotics, prebiotics, synbiotics, and postbiotics for the prevention and treatment of dental caries, taking into account the unique pathogenic mechanisms of dental caries. With an enhanced understanding of oral microbiota, personalized microbial therapy will emerge as a critical future research trend.

Effect of phosphate buffer concentration on the isomerization of galactose to rare sugars under subcritical water conditions

Galactose was treated in sodium phosphate buffer at various concentrations (0.1-500 mmol/L) under subcritical water conditions (140 °C), and the effects of the buffer concentration and reaction time (0-300 s) on the reaction behavior were evaluated. The reaction proceeded rapidly at higher buffer concentrations. Rare sugars (tagatose, talose, and sorbose) were formed from galactose by isomerization. The highest yield of the main product, tagatose, was approximately 14 % in 50 mmol/L buffer. However, the tagatose yield did not increase further with increasing buffer concentration. On the other hand, the formation of talose and sorbose was accelerated at higher buffer concentrations, with the highest yields of approximately 5 % and 12 %, respectively, in 500 mmol/L buffer. At the same time, the formation of byproducts (organic acids and colored substances) was also accelerated in high-concentration buffers. These results suggest that phosphate buffer promoted all reactions occurring under subcritical water conditions.

A novel and sensitive method for simultaneous determination of 6 low-calorie bulk sweeteners by HPLC-ELSD

A novel and sensitive method for the simultaneous analysis of six low-calorie bulk sweeteners (D-allulose, D-tagatose, D-mannitol, mycose, palatinose, and erythritol) without derivatisation was developed using high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD). Chromatographic separations were carried out on a Zorbax Original NH2 (5 μm particle size, 250 mm×4.60 mm id, 70 Å) column with flow rate gradient elution with acetonitrile: water (80:20, v/v). Drift tube temperature was set at 50 ℃, the nebuliser carrier gas flow rate was 1.0 mL·min-1, and nitrogen pressure was regulated to 276 kPa with gain:3. The regression equation showed good linearity (R2 = 0.9985-0.9998) for all six low-calorie bulk sweeteners in the tested range (0.060-0.60 mg·mL-1). The limits of detection (LOD) for the six low-calorie bulk sweeteners ranged from 0.02 to 0.06 mg·mL-1. The proposed HPLC-ELSD method was validated for the quantification of the low-calorie bulk sweeteners in 14 types of foods, and the results were satisfactory. In addition, the results showed that the number of sweeteners in each food product varied. The presence of multiple low-calorie bulk sweeteners in certain foods is interesting. This method is successful in monitoring low-calorie bulk sweeteners in food.

Production of D -tagatose, bioethanol, and microbial protein from the dairy industry by-product whey powder using an integrated bioprocess

We designed and constructed a green and sustainable bioprocess to efficiently coproduce D -tagatose, bioethanol, and microbial protein from whey powder. First, a one-pot biosynthesis process involving lactose hydrolysis and D -galactose redox reactions for D -tagatose production was established in vitro via a three-enzyme cascade. Second, a nicotinamide adenine dinucleotide phosphate-dependent galactitol dehydrogenase mutant, D36A/I37R, based on the nicotinamide adenine dinucleotide-dependent polyol dehydrogenase from Paracoccus denitrificans was created through rational design and screening. Moreover, an NADPH recycling module was created in the oxidoreductive pathway, and the tagatose yield increased by 3.35-fold compared with that achieved through the pathway without the cofactor cycle. The reaction process was accelerated using an enzyme assembly with a glycine-serine linker, and the tagatose production rate was 9.28-fold higher than the initial yield. Finally, Saccharomyces cerevisiae was introduced into the reaction solution, and 266.5 g of D -tagatose, 162.6 g of bioethanol, and 215.4 g of dry yeast (including 38% protein) were obtained from 1 kg of whey powder (including 810 g lactose). This study provides a promising sustainable process for functional food (D -tagatose) production. Moreover, this process fully utilized whey powder, demonstrating good atom economy.

Intestinal absorption of D-fructose isomers, D-allulose, D-sorbose and D-tagatose, via glucose transporter type 5 (GLUT5) but not sodium-dependent glucose cotransporter 1 (SGLT1) in rats

D-allulose, D-sorbose and D-tagatose are D-fructose isomers that are called rare sugars. These rare sugars have been studied intensively in terms of biological production and food application as well as physiological effects. There are limited papers with regard to the transporters mediating the intestinal absorption of these rare sugars. We examined whether these rare sugars are absorbed via sodium-dependent glucose cotransporter 1 (SGLT1) as well as via GLUT type 5 (GLUT5) using rats. High-fructose diet fed rats, which express more intestinal GLUT5, exhibited significantly higher peripheral concentrations, Cmax and AUC0–180 min when D-allulose, D-sorbose and D-tagatose were orally administrated. KGA-2727, a selective SGLT1 inhibitor, did not affect the peripheral and portal vein concentrations and pharmacokinetic parameters of these rare sugars. The results suggest that D-allulose, D-sorbose and D-tagatose are likely transported via GLUT5 but not SGLT1 in rat small intestine.

In Vitro Anti-Diabetic, Anti-Inflammatory, Antioxidant Activities and Toxicological Study of Optimized Psychotria malayana Jack Leaves Extract

Psychotria malayana Jack (Family: Rubiaceae, local name: Salung) is a traditional herb used to treat diabetes. A previous study by our research group demonstrated that P. malayana methanolic and water extract exhibits significant potential as an effective agent for managing diabetes. Further research has been performed on the extraction optimization of this plant to enhance its inhibitory activity against α-glucosidase, a key enzyme associated with diabetes, and to reduce its toxicity. The objectives of this study are to evaluate the anti-diabetic, anti-inflammatory, and antioxidant properties of the optimized P. malayana leaf extract (OE), to evaluate its toxicity using a zebrafish embryo/larvae model, and to analyze its metabolites. The anti-diabetic effects were assessed by investigating α-glucosidase inhibition (AGI), while the inflammation inhibitory activity was performed using the soybean lipoxygenase inhibitory (SLOXI) test. The assessment of antioxidant activity was performed utilizing FRAP and DPPH assays. The toxicology study was conducted using the zebrafish embryo/larvae (Danio rerio) model. The metabolites present in the extracts were analyzed using GC-MS and LC-MS. OE demonstrated significant AGI and SLOXI activities, represented as 2.02 and 4.92 µg/mL for IC50 values, respectively. It exhibited potent antioxidant activities as determined by IC50 values of 13.08 µg/mL (using the DPPH assay) and 95.44 mmol TE/mg DW (using the FRAP assay), and also demonstrated an LC50 value of 224.29 µg/mL, which surpasses its therapeutic index of 111.03. OE exhibited a higher therapeutic index compared to that of the methanol extract (13.84) stated in the previous state of the art. This suggests that OE exhibits a lower level of toxicity, making it safer for use, and has the potential to be highly effective in its anti-diabetic activity. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) demonstrated the presence of several constituents in this extract. Among them, several compounds, such as propanoic acid, succinic acid, D-tagatose, myo-inositol, isorhamnetin, moracin M-3'-O-β-D-glucopyranoside, procyanidin B3, and leucopelargonidin, have been reported as possessing anti-diabetic and antioxidant activities. This finding offers great potential for future research in diabetes treatment.

Metabolites of Pinang Yaki (Areca vestiaria) Fruit Extract: A Metabolite Profiling Study

Background: Pinang yaki has bioactive compounds that have potential as a new herbal supplement. A better understanding of the bioactive compounds of pinang yaki using untargeted metabolomic profiling studies will provide clearer insight into the health benefits of pinang yaki and in particular its potential for the therapy and prevention of Covid-19.   Methods: Fresh samples of pinang yaki ( Areca vestiaria) are obtained from forests in North Sulawesi Province, Indonesia. Samples were used for untargeted metabolomics analysis by UPLC-MS.   Results: Based on an untargeted metabolomic profiling study of pinang yaki, 2504 compounds in ESI- and 2645 compounds in ESI+ were successfully obtained. After the analysis, 356 compounds in ESI- and 543 compounds in ESI+ were identified successfully. Major compounds Alpha-Chlorohydrin (PubChem ID: 7290) and Tagatose (PubChem ID: 439312) were found in ESI+ and ESI-.   Discussion: The Top 10 metabolites from pinang yaki extract (ESI+) juga have been indicated in preventing SARS Cov2 infection and have exhibited good neuroprotective immunity. Benzothiazole (PubChem ID: 7222), L-isoleucine (PubChem ID: 6306), D-glucono-delta-lactone (PubChem ID: 736), Diethylpyrocarbonate (PubChem ID: 3051), Bis(2-Ethylhexyl) amine (PubChem ID: 7791), Cinnamic acid (PubChem ID: 444539), and Trigonelline (PubChem ID: 5570) also had potential effects as an antiviral, anti-inflammatory, and anti-Covid19.   Conclusion: Untargeted metabolomic profiling showed many bioactive compounds contained in pinang yaki ( Areca vestiaria) extract. The top 10 compounds have been identified and explored for their potential benefits as anti-Covid19 supplement products. This is a preliminary study which still needs further research such as preclinical and clinical trials.

Rare sugars: metabolic impacts and mechanisms of action: a scoping review

Food manufacturers are under increasing pressure to limit the amount of free sugars in their products. Many have reformulated products to replace sucrose, glucose and fructose with alternative sweeteners, but some of these have been associated with additional health concerns. Rare sugars are ‘monosaccharides and their derivatives that hardly exist in nature’, and there is increasing evidence that they could have health benefits. This review aimed to scope the existing literature in order to identify the most commonly researched rare sugars, to ascertain their proposed health benefits, mechanisms of action and potential uses and to highlight knowledge gaps. A process of iterative database searching identified fifty-five relevant articles. The reported effects of rare sugars were noted, along with details of the research methodologies conducted. Our results indicated that the most common rare sugars investigated are d-psicose and d-tagatose, with the potential health benefits divided into three topics: glycaemic control, body composition and CVD. All the rare sugars investigated have the potential to suppress postprandial elevation of blood glucose and improve glycaemic control in both human and animal models. Some animal studies have suggested that certain rare sugars may also improve lipid profiles, alter the gut microbiome and reduce pro-inflammatory cytokine expression. The present review demonstrates that rare sugars could play a role in reducing the development of obesity, type 2 diabetes and/or CVD. However, understanding of the mechanisms by which rare sugars may exert their effects is limited, and their effectiveness when used in reformulated products is unknown.

Characterization of inulolytic enzymes from the Jerusalem artichoke-derived Glutamicibacter mishrai NJAU-1

The rhizosphere context of inulin-accumulating plants, such as Jerusalem artichoke (Helianthus tuberosus), is an ideal starting basis for the discovery of inulolytic enzymes with potential for bio fructose production. We isolated a Glutamicibacter mishrai NJAU-1 strain from this context, showing exo-inulinase activity, releasing fructose from fructans. The growth conditions (pH 9.0; 15 °C) were adjusted, and the production of inulinase by Glutamicibacter mishrai NJAU-1 increased by 90% (0.32 U/mL). Intriguingly, both levan and inulin, but not fructose and sucrose, induced the production of exo-inulinase activity. Two exo-inulinase genes (inu1 and inu2) were cloned and heterologously expressed in Pichia pastoris. While INU2 preferentially hydrolyzed longer inulins, the smallest fructan 1-kestose appeared as the preferred substrate for INU1, also efficiently degrading nystose and sucrose. Active site docking studies with GFn- and Fn-type small inulins (G is glucose, F is fructose, and n is the number of β (2-1) bound fructose moieties) revealed subtle substrate differences between INU1 and INU2. A possible explanation about substrate specificity and INU's protein structure is then suggested. KEY POINTS: • A Glutamicibacter mishrai strain harbored exo-inulinase activity. • Fructans induced the inulolytic activity in G. mishrai while the inulolytic activity was optimized at pH 9.0 and 15 °C. • Two exo-inulinases with differential substrate specificity were characterized.

Recent Advances Regarding the Physiological Functions and Biosynthesis of D-Allulose

D-Allulose, a generally regarded as safe (GRAS) sugar, is rare in nature. It is among the most promising sweeteners for future use due to its low caloric content, sucrose-like taste, and unique functions. D-Allulose has many physiological effects, such as antiobesity, antihyperglycemia, antidiabetes, anti-inflammatory, antioxidant, and neuroprotective effects. Therefore, D-allulose has important application value in the food, pharmaceutical, and healthcare industries. However, the high cost of D-allulose production limits its large-scale application. Currently, biotransformation is very attractive for D-allulose synthesis, with the two main methods of biosynthesis being the Izumoring strategy and the DHAP-dependent aldolase strategy. This article reviews recent advances regarding the physiological functions and biosynthesis of D-allulose. In addition, future perspectives on the production of D-allulose are presented.

Potential of Prebiotic D-Tagatose for Prevention of Oral Disease

Recent studies have shown phenotypic and metabolic heterogeneity in related species including Streptococcus oralis, a typical oral commensal bacterium, Streptococcus mutans, a cariogenic bacterium, and Streptococcus gordonii, which functions as an accessory pathogen in periodontopathic biofilm. In this study, metabolites characteristically contained in the saliva of individuals with good oral hygiene were determined, after which the effects of an identified prebiotic candidate, D-tagatose, on phenotype, gene expression, and metabolic profiles of those three key bacterial species were investigated. Examinations of the saliva metabolome of 18 systemically healthy volunteers identified salivary D-tagatose as associated with lower dental biofilm abundance in the oral cavity (Spearman’s correlation coefficient; r = -0.603, p = 0.008), then the effects of D-tagatose on oral streptococci were analyzed in vitro. In chemically defined medium (CDM) containing D-tagatose as the sole carbohydrate source, S. mutans and S. gordonii each showed negligible biofilm formation, whereas significant biofilms were formed in cultures of S. oralis. Furthermore, even in the presence of glucose, S. mutans and S. gordonii showed growth suppression and decreases in the final viable cell count in a D-tagatose concentration-dependent manner. In contrast, no inhibitory effects of D-tagatose on the growth of S. oralis were observed. To investigate species-specific inhibition by D-tagatose, the metabolomic profiles of D-tagatose-treated S. mutans, S. gordonii, and S. oralis cells were examined. The intracellular amounts of pyruvate-derived amino acids in S. mutans and S. gordonii, but not in S. oralis, such as branched-chain amino acids and alanine, tended to decrease in the presence of D-tagatose. This phenomenon indicates that D-tagatose inhibits growth of those bacteria by affecting glycolysis and its downstream metabolism. In conclusion, the present study provides evidence that D-tagatose is abundant in saliva of individuals with good oral health. Additionally, experimental results demonstrated that D-tagatose selectively inhibits growth of the oral pathogens S. mutans and S. gordonii. In contrast, the oral commensal S. oralis seemed to be negligibly affected, thus highlighting the potential of administration of D-tagatose as an oral prebiotic for its ability to manipulate the metabolism of those targeted oral streptococci.

Preparation of combined cross-linked enzyme aggregates containing galactitol dehydrogenase and NADH oxidase for L-tagatose synthesis via in situ cofactor regeneration

The combined cross-linked enzyme aggregates (combi-CLEAs) containing galactitol dehydrogenase (Gdh) and NADH oxidase (Nox) were prepared for L-tagatose synthesis. To prevent the excess consumption of cofactor, Nox in the combi-CLEAs was used to in situ regenerate NAD⁺. In the immobilization process, ammonia sulfate and glutaraldehyde were used as the precipitant and cross-linking reagent, respectively. The preparation conditions were optimized as follows: 60% ammonium sulfate, 1:1 (molar ratio) of Gdh to Nox, 20:1 (molar ratio) of protein to glutaraldehyde, and 6 h of cross-linking time at 35 °C. Under these conditions, the activity of the combi-CLEAs was 210 U g^-1. The combi-CLEAs exhibited higher thermostability and preserved 51.5% of the original activity after eight cycles of reuses at 45 °C. The combi-CLEAs were utilized for the preparation of L-tagatose without by-products. Therefore, the combi-CLEAs have the industrial potential for the bioconversion of galactitol to L-tagatose.

D-Tagatose Feeding Reduces the Risk of Sugar-Induced Exacerbation of Myocardial I/R Injury When Compared to Its Isomer Fructose

It is known that fructose may contribute to myocardial vulnerability to ischemia/reperfusion (I/R) injury. D-tagatose is a fructose isomer with less caloric value and used as low-calorie sweetener. Here we compared the metabolic impact of fructose or D-tagatose enriched diets on potential exacerbation of myocardial I/R injury. Wistar rats were randomizedly allocated in the experimental groups and fed with one of the following diets: control (CTRL), 30% fructose-enriched (FRU 30%) or 30% D-tagatose-enriched (TAG 30%). After 24 weeks of dietary manipulation, rats underwent myocardial injury caused by 30 min ligature of the left anterior descending (LAD) coronary artery followed by 24 h′ reperfusion. Fructose consumption resulted in body weight increase (49%) as well as altered glucose, insulin and lipid profiles. These effects were associated with increased I/R-induced myocardial damage, oxidative stress (36.5%) and inflammation marker expression. TAG 30%-fed rats showed lower oxidative stress (21%) and inflammation in comparison with FRU-fed rats. Besides, TAG diet significantly reduced plasmatic inflammatory cytokines and GDF8 expression (50%), while increased myocardial endothelial nitric oxide synthase (eNOS) expression (59%). Overall, we demonstrated that D-tagatose represents an interesting sugar alternative when compared to its isomer fructose with reduced deleterious impact not only on the metabolic profile but also on the related heart susceptibility to I/R injury.

A head-to-head comparison review of biological and toxicological studies of isomaltulose, d-tagatose, and trehalose on glycemic control

Diabetes mellitus is the most common metabolic disorder contributing to significant morbidity and mortality in humans. Different preventive and therapeutic agents, as well as various pharmacological strategies or non-pharmacological tools, improve the glycemic profile of diabetic patients. Isomaltulose, d-tagatose, and trehalose are naturally occurring, low glycemic sugars that are not synthesized by humans but widely used in food industries. Various studies have shown that these carbohydrates can regulate glucose metabolism and provide support in maintaining glucose homeostasis in patients with diabetes, but also can improve insulin response, subsequently leading to better control of hyperglycemia. In this review, we discussed the anti-hyperglycemic effects of isomaltulose, D-tagatose, and trehalose, comparing their properties with other known sweeteners, and highlighting their importance for the development of the pharmaceutical and food industries.

Interactions of tagatose with the sugar metabolism are responsible for Phytophthora infestans growth inhibition

Tagatose is a rare sugar metabolised by a limited number of microorganisms that inhibits a large spectrum of phytopathogens. In particular, tagatose inhibited Phytophthora infestans growth and negatively affected mitochondrial processes. However, the possible effects of tagatose on P. infestans metabolism have not yet been investigated. The aim of this study was to analyse the impact of this rare sugar on the sugar metabolism in P. infestans, in order to better understand its mode of action. Tagatose inhibited the growth of P. infestans with a precise reprogramming of the carbohydrate metabolism that involved a decrease of glucose, glucose-1-phosphate and mannose content and β-glucosidase activity. The combination of tagatose with common sugars led to three different responses and highlighted antagonistic interactions. In particular, glucose partially attenuated the inhibitory effects of tagatose, while fructose fully impaired tagatose-mediated growth inhibition and metabolite changes. Moreover, sucrose did not attenuate tagatose effects, suggesting that the inhibition of sucrose catabolism and the alteration of glucose-related pathways contributed to the growth inhibition caused by tagatose to P. infestans. The interactions of tagatose with the common sugar metabolism were found to be a key mode of action against P. infestans growth, which may represent the basis for the further development of tagatose as an eco-friendly fungicide.

The sensory properties and metabolic impact of natural and synthetic sweeteners

The global rise in obesity, type II diabetes, and other metabolic disorders in recent years has been attributed in part to the overconsumption of added sugars. Sugar reduction strategies often rely on synthetic and naturally occurring sweetening compounds to achieve their goals, with popular synthetic sweeteners including saccharin, cyclamate, acesulfame potassium, aspartame, sucralose, neotame, alitame, and advantame. Natural sweeteners can be further partitioned into nutritive, including polyols, rare sugars, honey, maple syrup, and agave, and nonnutritive, which include steviol glycosides and rebaudiosides, luo han guo (monk fruit), and thaumatin. We choose the foods we consume largely on their sensory properties, an area in which these sugar substitutes often fall short. Here, we discuss the most popular synthetic and natural sweeteners, with the goal of providing an understanding of differences in the sensory profiles of these sweeteners versus sucrose, that they are designed to replace, essential for the effectiveness of sugar reduction strategies. In addition, we break down the influence of these sweeteners on metabolism, and present results from a large survey of consumers' opinions on these sweeteners. Consumer interest in clean label foods has driven a move toward natural sweeteners; however, neither natural nor synthetic sweeteners are metabolically inert. Identifying sugar replacements that not only closely imitate the sensory profile of sucrose but also exert advantageous effects on body weight and metabolism is critical in successfully the ultimate goals of reducing added sugar in the average consumer's diet. With so many options for sucrose replacement available, consumer opinion and cost, which vary widely with suagr replacements, will also play a vital role in which sweeteners are successful in widespread adoption.

Alternative Heterologous Expression of L-Arabinose Isomerase from Enterococcus faecium DBFIQ E36 By Residual Whey Lactose Induction

This study reports an alternative strategy for the expression of a recombinant L-AI from Enterococcus faecium DBFIQ E36 by auto-induction using glucose and glycerol as carbon sources and residual whey lactose as inducer agent. Commercial lactose and isopropyl β-D-1-thiogalactopyranoside (IPTG) were also evaluated as inducers for comparison of enzyme expression levels. The enzymatic extracts were purified by affinity chromatography, characterized, and applied in the bioconversion of D-galactose into D-tagatose. L-AI presented a catalytic activity of 1.67 ± 0.14, 1.52 ± 0.01, and 0.7 ± 0.04 U/mL, when expressed using commercial lactose, lactose from whey, and IPTG, respectively. Higher activities could be obtained by changing the protocol of enzyme extraction and, for instance, the enzymatic extract produced with whey presented a catalytic activity of 3.8 U/mL. The specific activity of the enzyme extracts produced using lactose (commercial or residual whey) after enzyme purification was also higher when compared to the enzyme expressed with IPTG. Best results were achieved when enzyme expression was conducted using 4 g/L of residual whey lactose for 11 h. These results proved the efficacy of an alternative and economic protocol for the effective expression of a recombinant L-AI aiming its high-scale production.

Optimization of fermentation conditions for production of l-arabinose isomerase of Lactobacillus plantarum WU14

As a substitute sweetener for sucrose, d-tagatose is widely used in products, such as health drinks, yogurt, fruit juices, baked goods, confectionery, and pharmaceutical preparations. In the fermentation process of l-AI produced by Lactobacillus plantarum, d-tagatose is produced through biotransformation and this study was based on the fermentation process of Lactobacillus plantarum WU14 producing l-AI to further research the biotransformation and separation process of d-tagatose. The kinetics of cell growth, substrate consumption, and l-arabinose isomerase formation were established by nonlinear fitting, and the fitting degrees were 0.996, 0.994, and 0.991, respectively, which could better reflect the change rule of d-tagatose biotransformation in the fermentation process of L. plantarum WU14. The separation process of d-tagatose was identified by decolorization, protein removal, desalination, and freeze drying, initially. Finally, the volume ratio of whole cell catalysts, d-galactose, and borate was 5:1:2 at 60°C, pH 7.17 through borate complexation; then, after 24 hr of conversion, the yield of d-tagatose was 58 g/L.

The unaided recovery of marathon-induced serum metabolome alterations

Endurance athlete performance is greatly dependent on sufficient post-race system recovery, as endurance races have substantial physiological, immunological and metabolic effects on these athletes. To date, the effects of numerous recovery modalities have been investigated, however, very limited literature exists pertaining to metabolic recovery of athletes after endurance races without the utilisation of recovery modalities. As such, this investigation is aimed at identifying the metabolic recovery trend of athletes within 48 h after a marathon. Serum samples of 16 athletes collected 24 h before, immediately after, as well as 24 h and 48 h post-marathon were analysed using an untargeted two-dimensional gas chromatography time-of-flight mass spectrometry metabolomics approach. The metabolic profiles of these comparative time-points indicated a metabolic shift from the overall post-marathon perturbed state back to the pre-marathon metabolic state during the recovery period. Statistical analyses of the data identified 61 significantly altered metabolites including amino acids, fatty acids, tricarboxylic acid cycle, carbohydrates and associated intermediates. These intermediates recovered to pre-marathon related concentrations within 24 h post-marathon, except for xylose which only recovered within 48 h. Furthermore, fluctuations in cholesterol and pyrimidine intermediates indicated the activation of alternative recovery mechanisms. Metabolic recovery of the athletes was attained within 48 h post-marathon, most likely due to reduced need for fuel substrate catabolism. This may result in the activation of glycogenesis, uridine-dependent nucleotide synthesis, protein synthesis, and the inactivation of cellular autophagy. These results may be beneficial in identifying more efficient, targeted recovery approaches to improve athletic performance.

N ε-(carboxymethyl)lysine formation from the Maillard reaction of casein and different reducing sugars

Dietary advanced glycation end products (AGEs) are involved in the pathogenesis of diabetic complications, atherosclerosis, and kidney disease. Formation of N ^ε-(carboxymethyl)lysine (CML), a well-known AGEs, was evaluated from the reaction of casein from bovine milk with different reducing sugars (glucose, tagatose, and xylose) at various sugar concentrations and heating temperatures (75 and 120 °C) used in food processing to determine the best sweetener to be used in dairy products. The concentration of CML was measured using an enzyme-linked immunosorbent assay. Additionally, SDS-PAGE was carried out to observe the changes in the molecular weight of casein. The results reveal that tagatose leads to a lower CML concentration at 75 °C than glucose or xylose, whereas no significant differences are observed at 120 °C. We conclude that it would be more appropriate to use tagatose rather than glucose or xylose as a sweetener, considering the AGEs contents in heat-treated dairy products.

Rare mono- and disaccharides as healthy alternative for traditional sugars and sweeteners?

Obesity and type 2 diabetes are major health problems affecting hundreds of millions of people. Caloric overfeeding with calorie-dense food ingredients like sugars may contribute to these chronic diseases. Sugar research has also identified mechanisms via which conventional sugars like sucrose and fructose can adversely influence metabolic health. To replace these sugars, numerous sugar replacers including artificial sweeteners and sugar alcohols have been developed. Rare sugars became new candidates to replace conventional sugars and their health effects are already reported in individual studies, but overviews and critical appraisals of their health effects are missing. This is the first paper to provide a detailed review of the metabolic health effects of rare sugars as a group. Especially allulose has a wide range of health effects. Tagatose and isomaltulose have several health effects as well, while other rare sugars mainly provide health benefits in mechanistic studies. Hardly any health claims have been approved for rare sugars due to a lack of evidence from human trials. Human trials with direct measures for disease risk factors are needed to allow a final appraisal of promising rare sugars. Mechanistic cell culture studies and animal models are required to enlarge our knowledge on understudied rare sugars.

Nonalcoholic fatty liver disease, insulin resistance, and sweeteners: a literature review

Introduction: Sweeteners are substances used to replace sugar. They can either be chemically produced (artificial sweeteners) or extracted from plants (natural sweeteners). In the last two decades, there is an increased popularity in their role as sugar substitutes in individuals to promote weight loss or maintain glycemic control. However, despite their favorable effects, there is concern regarding their side effects and especially their influence in the development of nonalcoholic fatty liver disease (NAFLD).Areas covered: A comprehensive literature search was conducted on Medline including systematic reviews, longitudinal controlled studies, and retrospective cohort studies. We present an up-to-date systematic review of the current literature regarding the safety in artificial and natural sweeteners use as a means of weight loss or diabetes control.Expert opinion: Natural sweeteners have not been associated directly with NAFLD, and on the contrary, some, such as stevia, and trehalose, may have a protective effect. Rare sugars and polyols can be used safely and have significant benefits that include anti-oxidant effect and optimal glycemic control. Artificial sweeteners, due to their effect on NAFLD development and insulin resistance, are not indicated in patients with obesity or diabetes. Further studies in human subjects are required to verify the above findings.

Effect of Oral Nutritional Supplements with Sucromalt and Isomaltulose versus Standard Formula on Glycaemic Index, Entero-Insular Axis Peptides and Subjective Appetite in Patients with Type 2 Diabetes: A Randomised Cross-Over Study

Oral diabetes-specific nutritional supplements (ONS-D) induce favourable postprandial responses in subjects with type 2 diabetes (DM2), but they have not been correlated yet with incretin release and subjective appetite (SA). This randomised, double-blind, cross-over study compared postprandial effects of ONS-D with isomaltulose and sucromalt versus standard formula (ET) on glycaemic index (GI), insulin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1) and SA in 16 individuals with DM2. After overnight fasting, subjects consumed a portion of supplements containing 25 g of carbohydrates or reference food. Blood samples were collected at baseline and at 30, 60, 90, 120, 150 and 180 min; and SA sensations were assessed by a visual analogue scale on separate days. Glycaemic index values were low for ONS-D and intermediate for ET (p < 0.001). The insulin area under the curve (AUC0-180 min) (p < 0.02) and GIP AUC (p < 0.02) were lower after ONS-D and higher GLP-1 AUC when compared with ET (p < 0.05). Subjective appetite AUC was greater after ET than ONS-D (p < 0.05). Interactions between hormones, hunger, fullness and GI were found, but not within the ratings of SA; isomaltulose and sucromalt may have influenced these factors.

Food Industrial Production of Monosaccharides Using Microbial, Enzymatic, and Chemical Methods

Most monosaccharides in nature are hexoses, which have six carbon atoms; the most well-known hexose is d-glucose. Various hexoses with distinct characteristics can be produced from inexpensive polysaccharides for applications in the food industry. Therefore, identification of the health-related functions of hexose will facilitate the consumption of hexoses in food products to improve quality of life. The hexoses available in foods include N-acetyl glucosamine, d-glucosamine, d-fructose, d-mannose, d-galactose, other d-hexoses, and l-hexoses. Here, an updated overview of food industrial production methods for natural hexoses by microbial, enzymatic, and chemical methods is provided.

Metabolic profiling reveals the heterogeneity of vascular endothelial function phenotypes in individuals at extreme cardiovascular risk

Maladapted vascular endothelial metabolism in the context of endothelial function differing in phenotype remains unknown, which limits our understanding of the heterogeneous pathogenesis of atherosclerotic cardiovascular disease (CVD). This study aimed to profile serum metabolic alterations of different vascular endothelial function phenotypes in asymptomatic adults at extreme cardiovascular risk. In addition to 12 CVD patients, 103 individuals free of CVD were categorized as having normal endothelial function (NEF) (n = 30), cardiovascular risk-promoting endothelial function (PEF) (n = 18), cardiovascular risk-resistant endothelial function (REF) (n = 25), and vulnerable endothelial function (VEF) (n = 30). Serum metabolic profiles were detected using gas chromatography time-of-flight/mass spectrometry and multivariate statistics. Compared to the NEF group, a total of 17, 17, 22, and 13 differential metabolites were identified in the PEF, REF, VEF, and CVD groups, respectively. Of the altered metabolic pathways, multiple pathways were consistent between the PEF and CVD groups, including pyrimidine metabolism, starch and sucrose metabolism, aminoacyl-tRNA biosynthesis, arginine and proline metabolism, and d-glutamine and d-glutamate metabolism. Notably, a relative increase in low-calorie sugar in galactose metabolism was exclusively found in the REF group, and a relative increase in the ratio of acetyl-CoA to CoA was suggested in the VEF group based on elevated butanoate metabolism and reduced pantothenate and CoA biosynthesis. Our findings clearly indicate distinct metabolic patterns across groups with heterogeneous vascular endothelial function in the context of extreme cardiovascular risk, and improve our understanding of the pathogenic heterogeneity of early CVD in asymptomatic populations.

This metabolomics analysis has revealed the maladapted vascular endothelial metabolism across individuals with heterogeneous vascular endothelial function in the context of extreme cardiovascular risk.