tagatose

BACKGROUND: Tetragenococcus (T.) halophilus is a common member of the microbial consortia of food fermented under high salt conditions. These comprises salty condiments based on soy or lupine beans, fish sauce, shrimp paste and brined anchovies. Within these fermentations this lactic acid bacterium (LAB) is responsible for the formation of lactic and other short chain acids that contribute to the flavor and lower the pH of the product. In this study, we investigated the transcriptomic profile of the two T...

In this study, the chromatographic behavior of mixed-mode and hydrophilic interaction liquid chromatography (HILIC) with the mixed-mode HILIC/strong anion-exchange (SAX) column HILICpak VT-50 2D and the two HILIC columns Atlantis Premier BEH Z-HILIC and Acquity Premier BEH Amide was assessed with regard to their separation capability of the metabolites from the glycolysis and pentose phosphate pathways. Chromatographic conditions were evaluated with the aim of achieving separation of the isomeric glycolytic phosphorylated carbohydrate metabolites free from isomeric interferences and thus allowing for selective targeted analysis by liquid chromatography with tandem mass spectrometry (MS/MS) using multiple reaction monitoring acquisition...

BACKGROUND: Gluconobacter oxydans, is used in biotechnology because of its ability to oxidize a wide variety of carbohydrates, alcohols, and polyols in a stereo- and regio-selective manner by membrane-bound dehydrogenases located in periplasmic space. These reactions obey the well-known Bertrand-Hudson's rule. In our previous study (BBA-General Subjects, 2021, 1865:129740), we discovered that Gluconobacter species, including G. oxydans and G. cerinus strain can regio-selectively oxidize the C-3 and C-5 hydroxyl groups of D-galactitol to rare sugars D-tagatose and L-xylo-3-hexulose, which represents an exception to Bertrand Hudson's rule...

D-Tagatose is a promising low-calorie sugar-substituting sweetener in the food industry. Most ingested D-tagatose is fermented by intestinal microorganisms. Until now, Escherichia coli has been considered incapable of growing on D-tagatose. Here, we discovered a gene cluster involved in D-tagatose utilization in E. coli . The chromosome of the intestinal probiotic E. coli Nissle 1917 contains a six-gene cluster encoding the ABC transporter, D-tagatose kinase, D-tagatose-bisphosphate aldolase, and putative aldose 1-epimerase...

Glucotoxicity, impaired insulin secretion, suppression of insulin gene expression and apoptosis, in pancreatic β-cells caused by chronic hyperglycemia is a key component of the pathogenesis of type 2 diabetes. Recently, it has been reported that rare sugar D-allulose has antihyperglycemic and antihyperlipidemic effects in diabetic rats. However, the direct effects of rare sugars including D-allulose on pancreatic β-cell function are unclear. In this study, we investigated whether chronic exposure to ketohexoses causes glucotoxicity, suppression of insulin gene expression and apoptosis, in INS-1 rat pancreatic insulinoma cells...

Rare sugar was defined as a sugar that occurs in very small quantities in nature. Among them, l-ribose and d-tagatose were of high added value and useful as pharmaceutical intermediate for anti-HBV drugs or low calorie sweetener in food industry. Bio-production of the two rare sugar from biomass waste has not been investigated. Hence, development of a feasible and efficient co-production method was of practical usage. However, lack of suitable biocatalyst has become a bottleneck. By sequence alignment and analysis, a C-terminal α-helix from l-arabinose isomerase (L-AI) family was selected as a tool for protein engineering...

The prebiotic generation of sugars in the context of origins of life studies is of considerable interest. Among the important intramolecular processes of sugars are carbonyl migrations and accompanying epimerizations. Herein we describe the carbonyl migration-epimerization process occurring down the entire carbon chain of chirally pure d-tetroses sugars under mild conditions. Employing chirally pure 1-13C-erythrose, 4-13C-erythrose and 1-13C-threose, we (1) identify all the species formed as the carbonyl migrates down the four-carbon chain and (2) assess the rates associated with the production of each of these species...

Immobilized enzymes are better suited for industrial applications than free enzymes due to their favorable properties such as ease of separation and reuse, and enhanced stability and storage life. β-Galactosidases are an important class of glycosidases with hydrolysis and transglycosylation activities, which are applied in industries for lactose hydrolysis and prebiotics synthesis worldwide. The recent innovations in immobilized β-galactosidases have improved the performance of the immobilized enzymes and broadened their applications in the fields of food, energy, and medicine...

Tagatose is a rare sugar that suppresses plant diseases, such as late blight of tomato, caused by Phytophthora infestans . Tagatose can be metabolized by some microorganisms and no information is available on its persistence on tomato leaves. The aim of this study was to assess the persistence of tagatose on tomato leaves under commercial greenhouse conditions. The amount of tagatose on tomato leaves and the inhibitory activity against P. infestans decreased seven days after spray application in the absence of rain wash-off...

Incorporation of microalgae in biorefineries intended to help society reach carbon neutrality is hindered by algal growth inhibition at high temperatures, necessitating the use of costly and carbon-intensive cooling systems. In the present study, a two-prong strategy of random mutagenesis and adaptive laboratory evolution to generate robust thermotolerant strains of Nannochloropsis oculata, was used. The best mutants demonstrated increased productivity at 35°C, which was 10°C higher than the optimal temperature of the wild type...

Starch retrogradation is desirable for some food textures and nutritional traits but detrimental to sensory and storage qualities of other foods. The objective of this study was to determine the impact of sweetener structure and concentration on the retrogradation of wheat starch gels. The effects of 20 sweeteners selected based on common food usage and stereochemical structures of interest, and ranging in concentration from 10 to 50% w / w , on the retrogradation of wheat starch gels were monitored spectrophotometrically over time...

Arsenic (As) contamination is continuously increasing in the groundwaters and soils around the world causing toxicity in the plants with a detrimental effect on physiology, growth, and yield. In a hydroponic system, thirty-day-old plants of Trigonella foenum-graecum were subjected to 0, 50, or 100 µM NaHAsO4 0.7 H2 O for 10 days. The magnitude of oxidative stress increased, whereas growth indices and photosynthetic parameters decreased in a dose-dependent manner. The efficiency of photosystem II in terms of Hill reaction activity (HRA) or chlorophyll-a was adversely affected by As stress...

Acute respiratory distress syndrome (ARDS) is characterized by disruption of the alveolar-capillary barrier, resulting in severe alveolar edema and inflammation. D-tagatose (TAG) is a low-calorie fructose isomer with diverse biological activities whose role in ARDS has never been explored. We found that TAG protects lung tissues from injury in the oleic acid-induced rat model of ARDS. Seventeen male Sprague-Dawley rats were randomly assigned to 3 groups: Sham (n = 5), ARDS (n = 6), and TAG + ARDS (n = 6). The treatment groups were injected with oleic acid to induce ARDS, and the TAG + ARDS group was given TAG 3 days before the induction...

Streptococcus suis type 2 (S. suis type 2, SS2), an infectious pathogen which is zoonotic and can induce severely public health concern. Our previous research identified a newly differential secreted effector of tagatose-bisphosphate aldolase (LacD) mediated by VirD4 factor within the putative type IV secretion system of SS2, whereas the functional basis and roles in virulence of LacD remain elusive. Here in this study, the LacD was found enzymatic and can be activated to express under oxidative stress. Gene mutant and its complemental strain (ΔlacD and cΔlacD) were constructed to analyze the phenotypes, virulence and transcriptomic profiles as compared with the parental strain...

This work investigated the isomerization of galactose to tagatose, a low caloric rare sugar, using arginine as a catalyst. Galactose (5 % w/v) and arginine (0.10 mol/mol-galactose) in water were treated at 90-120 °C. The results showed that as the temperature and time increased, galactose was continuously consumed. Rare sugars namely tagatose, talose, and sorbose were formed with the highest yield of 16.8, 2.7, and 3.3 %, respectively at 120 °C, 20 min. High temperature and short time conditions resulted in lower Maillard reaction extent...

Impurity sugars produced in upstream process of functional sugars are significantly impacting the product quality. In this work, the effect of congeners (d-maltose (d-MAL), d-fructose (d-FRU), d-glucose (d-GLU)) on primary and secondary nucleation of d-tagatose (d-TAG) crystals was investigated. The impurity sugars showed an inhibition on primary nucleation of d-TAG crystals, while a promotion on the secondary nucleation of d-TAG. Interestingly, the impact of impurity sugars on d-TAG crystal growth was similar to that on primary nucleation...

BACKGROUND: Rare sugars have become promising 'sugar alternatives' because of their low calories and unique physiological functions. Among the family of rare sugars, D-allulose is one of the sugars attracting interest. Ketose 3-epimerases (KEase), including D-tagatose 3-epimerase (DTEase) and D-allulose 3-epimerase (DAEase), are mainly used for D-allulose production. RESULTS: In this study, a putative xylose isomerase from Caballeronia insecticola was characterized and identified as a novel DAEase...

Dairy industry waste has been explored as a cheap and attractive raw material to produce various commercially important rare sugars. In this study, a lactose-rich dairy byproduct, namely cheese whey powder (CWP), was microbially converted into three low caloric sweeteners using whole-cell and fermentation technologies. Firstly, the simultaneous lactose hydrolysis and isomerization of lactose-derived D-galactose into D-tagatose was performed by an engineered Escherichia coli strain co-expressing β-galactosidase and L-arabinose isomerase, which eventually produced 68...

Many oral bacteria employ cell wall-anchored adhesins to bind to the salivary films coating the teeth and mucosal surfaces. Surface binding prevents clearance and facilitates catabolism of salivary film glycoproteins. We asked whether Streptococcus gordonii adhesin expression changes in response to surface salivary cues using a eukaryote-like, outside-in recognition and signaling circuit. To determine whether the cues were discriminated, S. gordonii was tested during cell adhesion and biofilm formation on a MUC5B-rich or lower-molecular-mass salivary fraction or an uncoated abiotic surface...

OBJECTIVE: To examine the effects of d-tagatose or stevia preloads on carbohydrate metabolism markers after an oral glucose load, as well as subjective and objective appetite in women with insulin resistance (IR). RESEARCH DESIGN AND METHODS: Randomized controlled crossover study. Women with IR without T2DM (n = 33; aged 23.4 ± 3.8; BMI 28.1 ± 3.4 kg × m-2 ) underwent three oral glucose loads (3 h each) on three different days. Ten min before oral glucose load, volunteers consumed a preload of 60 mL water (control), 60 mL water with stevia (15...