Conventional Sugars Research Articles

Rare Sugar Metabolism and Impact on Insulin Sensitivity along the Gut-Liver-Muscle Axis In Vitro.

Rare sugars have recently attracted attention as potential sugar replacers. Understanding the biochemical and biological behavior of these sugars is of importance in (novel) food formulations and prevention of type 2 diabetes. In this study, we investigated whether rare sugars may positively affect intestinal and liver metabolism, as well as muscle insulin sensitivity, compared to conventional sugars. Rare disaccharide digestibility, hepatic metabolism of monosaccharides (respirometry) and the effects of sugars on skeletal muscle insulin sensitivity (impaired glucose uptake) were investigated in, respectively, Caco-2, HepG2 and L6 cells or a triple coculture model with these cells. Glucose and fructose, but not l-arabinose, acutely increased extracellular acidification rate (ECAR) responses in HepG2 cells and impaired glucose uptake in L6 cells following a 24 h exposure at 28 mM. Cellular bioenergetics and digestion experiments with Caco-2 cells indicate that especially trehalose (α1-1α), D-Glc-α1,2-D-Gal, D-Glc-α1,2-D-Rib and D-Glc-α1,3-L-Ara experience delayed digestion and reduced cellular impact compared to maltose (α1-4), without differences on insulin-stimulated glucose uptake in a short-term setup with a Caco-2/HepG2/L6 triple coculture. These results suggest a potential for l-arabinose and specific rare disaccharides to improve metabolic health; however, additional in vivo research with longer sugar exposures should confirm their beneficial impact on insulin sensitivity in humans.

Rare Sugars: Recent Advances and Their Potential Role in Sustainable Crop Protection.

Rare sugars are monosaccharides with a limited availability in the nature and almost unknown biological functions. The use of industrial enzymatic and microbial processes greatly reduced their production costs, making research on these molecules more accessible. Since then, the number of studies on their medical/clinical applications grew and rare sugars emerged as potential candidates to replace conventional sugars in human nutrition thanks to their beneficial health effects. More recently, the potential use of rare sugars in agriculture was also highlighted. However, overviews and critical evaluations on this topic are missing. This review aims to provide the current knowledge about the effects of rare sugars on the organisms of the farming ecosystem, with an emphasis on their mode of action and practical use as an innovative tool for sustainable agriculture. Some rare sugars can impact the plant growth and immune responses by affecting metabolic homeostasis and the hormonal signaling pathways. These properties could be used for the development of new herbicides, plant growth regulators and resistance inducers. Other rare sugars also showed antinutritional properties on some phytopathogens and biocidal activity against some plant pests, highlighting their promising potential for the development of new sustainable pesticides. Their low risk for human health also makes them safe and ecofriendly alternatives to agrochemicals.

Oral Microbiota Display Profound Differential Metabolic Kinetics and Community Shifts upon Incubation with Sucrose, Trehalose, Kojibiose, and Xylitol.

This study compares the metabolic properties of kojibiose, trehalose, sucrose, and xylitol upon incubation with representative oral bacteria as monocultures or synthetic communities or with human salivary bacteria in a defined medium. Compared to sucrose and trehalose, kojibiose resisted metabolism during a 48-h incubation with monocultures, except for Actinomyces viscosus Incubations with Lactobacillus-based communities, as well as salivary bacteria, displayed kojibiose metabolism, yet to a lesser extent than sucrose and trehalose. Concurring with our in vitro findings, screening for carbohydrate-active enzymes revealed that only Lactobacillus spp. and A. viscosus possess enzymes from glycohydrolase (GH) families GH65 and GH15, respectively, which are associated with kojibiose metabolism. Donor-dependent differences in salivary microbiome composition were noted, and differences in pH drop during incubation indicated different rates of sugar metabolism. However, functional analysis indicated that lactate, acetate, and formate evenly dominated the metabolic profile for all sugars except for xylitol. 16S rRNA gene sequencing analysis and α-diversity markers revealed that a significant shift of the microbiome community by sugars was more pronounced in sucrose and trehalose than in kojibiose and xylitol. In Streptococcus spp., a taxon linked to cariogenesis dominated in sucrose (mean ± standard deviation, 91.8 ± 6.4%) and trehalose (55.9 ± 38.6%), representing a high diversity loss. In contrast, Streptococcus (5.1 ± 3.7%) was less abundant in kojibiose, which instead was dominated by Veillonella (26.8 ± 19.6%), while for xylitol, Neisseria (29.4 ± 19.1%) was most abundant. Overall, kojibiose and xylitol incubations stimulated cariogenic species less yet closely maintained an abundance of key phyla and genera of the salivary microbiome, suggesting that kojibiose has low cariogenic properties.IMPORTANCE This study provides a detailed scientific insight on the metabolism of a rare disaccharide, kojibiose, whose mass production has recently been made possible. While the resistance of kojibiose was established with monocultures, delayed utilization of kojibiose was observed with communities containing lactobacilli and A. viscosus as well as with complex communities of bacteria from human saliva. Kojibiose is, therefore, less metabolizable than sucrose and trehalose. Moreover, although conventional sugars cause distinct shifts in salivary microbial communities, our study has revealed that kojibiose is able to closely maintain the salivary microbiome composition, suggesting its low cariogenic properties. This study furthermore underscores the importance and relevance of microbial culture and ex vivo mixed cultures to study cariogenicity and substrate utilization; this is in sharp contrast with tests that solely rely on monocultures such as Streptococcus mutans, which clearly fail to capture complex interactions between oral microbiota.

Reconstruction and analysis of a Kluyveromyces marxianus genome-scale metabolic model

BackgroundKluyveromyces marxianus is a thermotolerant yeast with multiple biotechnological potentials for industrial applications, which can metabolize a broad range of carbon sources, including less conventional sugars like lactose, xylose, arabinose and inulin. These phenotypic traits are sustained even up to 45 °C, what makes it a relevant candidate for industrial biotechnology applications, such as ethanol production. It is therefore of much interest to get more insight into the metabolism of this yeast. Recent studies suggested, that thermotolerance is achieved by reducing the number of growth-determining proteins or suppressing oxidative phosphorylation. Here we aimed to find related factors contributing to the thermotolerance of K. marxianus.ResultsHere, we reported the first genome-scale metabolic model of Kluyveromyces marxianus, iSM996, using a publicly available Kluyveromyces lactis model as template. The model was manually curated and refined to include the missing species-specific metabolic capabilities. The iSM996 model includes 1913 reactions, associated with 996 genes and 1531 metabolites. It performed well to predict the carbon source utilization and growth rates under different growth conditions. Moreover, the model was coupled with transcriptomics data and used to perform simulations at various growth temperatures.ConclusionsK. marxianus iSM996 represents a well-annotated metabolic model of thermotolerant yeast, which provides a new insight into theoretical metabolic profiles at different temperatures of K. marxianus. This could accelerate the integrative analysis of multi-omics data, leading to model-driven strain design and improvement.

Abstract #231 Ambulatory Glucose Profiling (Agp) Helps Bridge the Glycaemic Gap Between Conventional Sugars and Hba1C Thus Facilitating Better Control in Younger Patients and Those with Unpredictable Lifestyles

Abstract #231 Ambulatory Glucose Profiling (Agp) Helps Bridge the Glycaemic Gap Between Conventional Sugars and Hba1C Thus Facilitating Better Control in Younger Patients and Those with Unpredictable Lifestyles

Farmer readiness for adopting stevia cultivation (a case study at District of Pasir Jambu, Regency of Bandung)

Recognized as a complementary for conventional sugars made from cane, coconut, corn, and palm, as well as a substitute for synthetic sweetener, recently stevia has accepted significant attention in order to fulfill increasing demand for sweeteners in Indonesia. Stevia has several advantages, among other is having 200-300 times sweetness level compared to cane sugar with low-calorie level. In Indonesia, stevia was introduced from Japan, Korea and China, and has been cultivated in several areas, among other is in West Java, particularly at District of Cikajang (Garut), District of Pangalengan (Bandung) and District of Ciwidey/Pasir Jambu (Bandung). Introducing new commodity and/or technology has usually faced constraints and sometimes rejection. However, considering the potentials and increasing demand for it, stevia cultivation widespread need to be stimulated. This paper describes several conditions of farmer community at District of Pasir Jambu in terms of their readiness to adopt stevia cultivation in their land. Community readiness model was used to guide the structure of thinking in data collection process at farmer level in order to compose possible best intervention based on farmer aspiration and condition. In addition, several references from previous research reports, journal articles as well as government reports were used to sharpen analysis of data and information collected from the field.

Activation of futile cycles as an approach to increase ethanol yield during glucose fermentation in Saccharomyces cerevisiae

ABSTRACTAn increase in ethanol yield by yeast from the fermentation of conventional sugars such as glucose and sucrose is possible by reducing the production of a key byproduct such as cellular biomass. Previously we have reported that overexpression of PHO8 gene encoding non-specific ATP-hydrolyzing alkaline phosphatase can lead to a decrease in cellular ATP content and to an increase in ethanol yield during glucose fermentation by Saccharomyces cerevisiae. In this work we further report on 2 new successful approaches to reduce cellular levels of ATP that increase ethanol yield and productivity. The first approach is based on the overexpression of the heterologous Escherichia coli apy gene encoding apyrase or SSB1 part of the chaperon that exhibit ATPase activity in yeast. In the second approach we constructed a futile cycle by the overexpression of S. cerevisiae genes encoding pyruvate carboxylase and phosphoenolpyruvate carboxykinase in S. cerevisiae. These genetically engineered strains accumulated more ethanol compared to the wild-type strain during alcoholic fermentation.

S tevia rebaudiana , Oligofructose and Isomaltulose as Sugar Replacers in Marshmallows: Stability and Antioxidant Properties

Consumers are increasingly demanding products with natural ingredients and functional properties. The replacement of conventional sugars with recently available sugars or sweeteners could result in the perception of candies as healthier products. Therefore, the objective of this work was to evaluate the influence of isomaltulose, oligofructose and stevia extracts on the physicochemical, mechanical, optical and antioxidant properties as well as the shelf life of marshmallows. A sensory test was carried out in order to evaluate the influence of these ingredients on the acceptance of this product. The instrumental and sensorial textural results indicate that the sucrose and glucose syrup in commercial marshmallows could be replaced by a mixture of isomaltulose, oligofructose and stevia. Adults found the new and the traditional marshmallows to be very similar. However, children only found similarities in terms of the texture. These new marshmallows, besides being more microbiologically stable, have added value due to their antioxidant properties. Practical Applications Society is becoming increasingly aware of the importance of nutrition in health, and this has a decisive impact on the proposals of the candy sector in terms of innovation and new product development. The main trends of the market are focused on eliminating the unhealthy ingredients in the formulations, such as sugars, and even incorporate active ingredients with functional properties, but without forgetting customer satisfaction. At present, the industry is using both intense and volume artificial sweeteners as conventional sugar substitutes. However, the food industry now has the possibility of using alternative natural sweeteners such as stevia, oligofructose and isomaltulose, with the added value of providing certain healthy benefits. The results of the present study could provide pertinent information to the confectionary industry that wishes to take on the challenge of developing candies with functional ingredients.

Confectionery technology and the pros and cons of using non-sucrose sweeteners

One use for alternative sweeteners is to replace the more conventional sugars in existing products. Sucrose is the basic ingredient for traditional sugar confectionery, and the whole industry has been built around its physical and chemical properties. These combine with those of the other sugars used, particularly glucose syrups and invert sugar, to provide the essential features of sucrose-based confectionery. They would have to be matched by any other sweetener which was used to replace them. Consideration will be given to the properties of sucrose and glucose syrups, and they will be compared with those of some of the alternative sweeteners. The implications that any differences in properties have on the application of the new sweeteners in confectionery production will then be discussed.

A New Class of Nucleoside Analogues. Synthesis of N. -Pyrimidinyl-and N9-Purinyl-4′-hydrqxy-3-(Hydsoxymethyl)butanes1 # 2

Abstract Interest in non-glycosidic derivatives of the nucleo-bases uracil, theymine, cytosine, adenine and guanine stems from their status as nucleoside analogues. It is noteworty in this connection that the anti-biotics aristeromycin3 and eritadenine4 consist of an adenine moiety linked, via N9 -, to a cyclopentyl or a butiric acid derivative, respectively, in place of the conventional nucleoside sugars. A non-glycoaidic 5-fluorouracil derivative5 has been recently reported to be clinically effective in the treatment of Gastrointestinal cancer. In this communication the ficile synthesis of 4-hydroxy-3-(hydroxymethyl)butyl derivatives of the nucleobases (1) is described. These nucleoside analogues are characterized by the special feature that they incorporate two hydroxyl functions in a relationship corresponding to the 3′-and 5′-hydroxy groups of the 2-deodyribose Doiety. Phosphorylationj of the hydroxyl groups or their linkage via phosphodiester of the hydroxyl groups or their linkage via phosphodieste...