Role Of Sugars Research Articles

Molecular dialogue between light and temperature signaling in plants: From perception to thermotolerance.

Light and temperature are the two most variable environmental signals, which significantly regulate plant growth and development. Plants in the natural environment usually encounter warmer temperatures during the day and cooler temperatures at night, suggesting both light and temperature are closely linked signals. Due to global warming, it has become important to understand how light and temperature signaling pathways converge, and regulate plant development. This review outlines diverse mechanisms of light and temperature perception and downstream signaling, with an emphasis on their integration and interconnection. The recent research has highlighted the regulation of thermomorphogenesis by photoreceptors and their downstream light signaling proteins under different light conditions, and circadian clock components at warm temperatures. We have made an attempt to comprehensively describe these studies and demonstrate their connection with plant developmental responses. We have also explained how gene signaling pathways of light and thermomorphogenesis, are interconnected with HSR-mediated thermotolerance, which reveals new avenues to manipulate plants for climate resilience. In addition, the role of sugars as signaling molecules between light and temperature is also highlighted. Thus, we envisage that such detailed knowledge will enhance the understanding of how plants perceive light and temperature cues simultaneously and bring about responses that help in their adaptation.

Transcriptomic and metabolomic profiling provide insight into the role of sugars and hormones in leaf senescence of Pinellia ternata.

The interaction network and pathway map uncover the potential crosstalk between sugar and hormone metabolisms as a possible reason for leaf senescence in P. ternata. Pinellia ternata, an environmentally sensitive medicinal plant, undergoes leaf senescence twice a year, affecting its development and yield. Understanding the potential mechanism that delays leaf senescence could theoretically decrease yield losses. In this study, a typical senescent population model was constructed, and an integrated analysis of transcriptomic and metabolomic profiles of P. ternata was conducted using two early leaf senescence populations and two stay-green populations. The result showed that two key gene modules were associated with leaf senescence which were mainly enriched in sugar and hormone signaling pathways, respectively. A network constructed by unigenes and metabolisms related to the obtained two pathways revealed that several compounds such as D-arabitol and 2MeScZR have a higher significance ranking. In addition, a total of 130 hub genes in this network were categorized into 3 classes based on connectivity. Among them, 34 hub genes were further analyzed through a pathway map, the potential crosstalk between sugar and hormone metabolisms might be an underlying reason of leaf senescence in P. ternata. These findings address the knowledge gap regarding leaf senescence in P. ternata, providing candidate germplasms for molecular breeding and laying theoretical basis for the realization of finely regulated cultivation in future.

Neurochemical Effects of the Adipokinetic Hormone/Red Pigment Concentrating Hormone Family of Peptides in MK-801-Induced Schizophrenia Rat Model

Objective: Adipokinetic hormone (AKH) plays a role in sugar and lipid metabolism in insects. Previous studies of AKH showed memory improvements in a schizophrenia rat model that displayed memory impairment and reduced depression in a rat olfactory bulbectomy model. In this study, we investigated the effects of the adipokinetic hormone/red pigment-concentrating hormone (AKH/RPCH) family of peptides on brain neurotransmitter levels and brain neurochemistry in a schizophrenia rat model. Materials and Methods: We administered AKH/RPCH peptides for 4 days sub-chronically, both in naive rats and also in the MK-801-induced schizophrenia rat model. Liquid chromatography-mass spectrometry apparatus was used for targeted and untargeted analysis of rat neurochemistry. Results: Increased brain glutamate levels characteristic of MK-801 peptide-treated rats were significantly reduced by AKH. Furthermore, AKH also increased brain dopamine levels in both naive and MK-801 rats. Metabolomic studies have shown that AKH affects lipid and glutamate metabolism, while hypertrehalosaemic hormone plays a role in sugar metabolism and inflammation. Conclusion: According to our results, AKH might affect dopaminergic and glutamatergic systems and reverse the effects of MK-801, possibly affecting NMDA receptors.

Role of sugar and energy metabolism in apple flesh browning during cold storage

In order to uncover the roles of soluble sugars and energy levels in the flesh browning of apple fruit during refrigeration, the differences of sugar and energy metabolism among the normal flesh tissue of normal fruit (Control) and the normal (FN) and browning (FB) tissue of browning fruit were investigated. Results revealed that the FB tissue exhibited the lowest levels of fructose, glucose, and sucrose. The activities of acid/neutral/cell wall invertase and their transcriptional levels were highest in FB tissue, while sucrose synthase and sucrose phosphate synthase have the opposite. Moreover, succinic dehydrogenase, cytochrome-c oxidase, H+-and Ca2+-ATPase activities were down-regulated in the FB tissue, resulting in the lowest levels of energy charge, adenosine triphosphate, and adenosine diphosphate compared with the non-browning tissues. These findings suggest that the browning of apple flesh during cold storage is associated with a decrease in soluble sugars and energy levels.

Role of sugar and sugar alcohols in the wet-curing process of unheated meat products in Japan

Role of sugar and sugar alcohols in the wet-curing process of unheated meat products in Japan

Identification of CmACL genes in melon and analysis of their potential functions in fruit sugar and acid accumulation.

Citric acid is the most important organic acid in melon and has a great influence on fruit flavor quality. ATP-citrate (pro-S) lyase (ACL) is a key regulator in the acetyl-CoA pathway and plays an important role in citric acid metabolism. In this study we analyzed the structure and phylogenetics of CmACL genes and their functions in sugar and acid accumulation in melon. A total of four CmACL genes were identified in the melon genome, and phylogenetic analysis assigned these genes into the α subfamily (CmACLα1 and CmACLα2) and the β subfamily (CmACLβ1 and CmACLβ2). Conserved motif and gene structure analyses showed that members of the same subfamily shared identical conserved motifs and gene structures, and probably have similar biological functions. Analysis of cis-acting elements revealed that CmACL promoter sequences contained regulatory elements related to light, stress, phytohormones, and growth and development, indicating that CmACL genes may be involved in melon growth and stress responses. The prediction of protein interaction network showed that CmACL proteins were closely related to the proteins belonging to tricarboxylic acid cycle, glyoxylic acid cycle and glycolytic pathway, suggesting that CmACL proteins may play an important role in sugar and acid metabolism. The expression of CmACLβ1 was significantly and positively correlated with sucrose content, and CmACLβ2 expression was significantly positively correlated with citric acid content, suggesting that CmACLβ1 and CmACLβ2 have important roles in sugar and acid accumulation in melon. Our results offer novel insights and avenues for the regulation of sugar and acid levels in melon and provide a theoretical foundation for breeding high-quality melon cultivars.

Impact of carbohydrate metabolism pathways on bearing habit of mango (Mangifera indica L.) genotypes

Heterozygosity is the major constraint in perennial fruit crop like mango for regular bearing breeding. Majority of the popular mango varieties have irregular bearing habit. Many external and internal factors affect the bearing habit of perennial fruit crops. Among internal factors, the level of carbohydrate reserves and phytohormones plays a major role on bearing habit of fruit crops like apple, citrus, mango, litchi etc., Therefore, present research work aimed to study the carbohydrate metabolism pathways in regular and irregular mango genotypes of varying origin. A total of 30 primers were designed using in silico mining of four key genes coding for citrate synthase, alcohol dehydrogenase, sucrose phosphate synthase and trehalose phosphate synthase. These genes play important role in sugar and starch metabolism in mango. Of these specific primers, 14 showed polymorphism among the genotypes studied. Gene diversity (GD), average number of alleles per locus (An), polymorphism information content (PIC) and major allele frequency (Maf) observed were 0.45, 2.14, 0.35, 0.59, respectively. Simple sequence repeats markers grouped 63.15% studied mango genotypes of regular bearers together. Further, these markers could be utilized in a greater number of genotypes for regularity.

Sucrose Signaling Contributes to the Maintenance of Vascular Cambium by Inhibiting Cell Differentiation.

Plants produce sugars by photosynthesis and use them for growth and development. Sugars are transported from source-to-sink organs via the phloem in the vasculature. It is well known that vascular development is precisely controlled by plant hormones and peptide hormones. However, the role of sugars in the regulation of vascular development is poorly understood. In this study, we examined the effects of sugars on vascular cell differentiation using a vascular cell induction system named 'Vascular Cell Induction Culture System Using Arabidopsis Leaves' (VISUAL). We found that sucrose has the strongest inhibitory effect on xylem differentiation, among several types of sugars. Transcriptome analysis revealed that sucrose suppresses xylem and phloem differentiation in cambial cells. Physiological and genetic analyses suggested that sucrose might function through the BRI1-EMS-SUPPRESSOR1 transcription factor, which is the central regulator of vascular cell differentiation. Conditional overexpression of cytosolic invertase led to a decrease in the number of cambium layers due to an imbalance between cell division and differentiation. Taken together, our results suggest that sucrose potentially acts as a signal that integrates environmental conditions with the developmental program.

Classic Experiments in Education Technology

Classic experiments in Biomedicine are presented that inspire students to enthusiastically continue in this field, written by a U.S. Presidential Award winning, American Association for the Advancement of Science Fellow. Four experiments are selected: the structure of DNA, the structure of the cell membrane, sugars in cell adhesion, and unconventional dealing with a deadly cancer problem. Papers, written mostly by students, from the author’s lab are also included that support the concept that students will enter a science research field if they are introduced to it by easy to read, enjoyable, papers. Some of the author’s papers strongly support one of the Classics presented, the role of sugars in cell adhesion. Using these Classics to teach students at all levels is presented, as the author has used them for decades, helping him win a US Presidential Award for Mentoring and supporting his election as Fellow, American Association for the Advancement of Science (AAAS) (Note 1). This approach helps students to understand the personalities involved in great discoveries, making them unforgettable.

Hazardous Chemical Compounds in Cookies: The Role of Sugars and the Kinetics of Their Formation during Baking.

Baking goods are an essential part of the diet worldwide and are consumed daily, so they represent ideal foods for vehicle health- and unhealth-promoting substances. This work aimed to study the influence of sugars and baking conditions of cookies on the final levels of the main reported hazardous chemical compounds such as 5-hydroxymethylfurfural (HMF), 3-deoxyglucosone (3-DG), glyoxal (GO) and methylglyoxal (MGO). The replacement of sucrose with fructose or glucose in the cookies recipe deeply modifies the levels of α-dicarbonyl compounds (DCs), particularly 3-DG, independently of the baking temperature used. A longer baking time, even a few minutes, can drastically modify the HMF level in cookies and the use of fructose or glucose in the recipe seems to ensure the optimal conditions for generating this compound. The use of sucrose is required to keep levels of the hazardous compounds below a few mg/kg. Additionally, the ability to retain water, the titratable acidity and/or the pH of the final products were influenced by the used sugars with effects on the final levels of DCs and HMF. The highest Ea values determined for DCs and HMF formation in the cookies with sucrose suggest that this system requires very high temperatures to increase meaningful levels of these molecules, limiting their accumulation.

Sugars as the regulators of dormancy and sprouting in geophytes

Geophytes develop underground storage organs, which help them to survive extreme environments. Besides energy resources for plants and humans, they are widely used for vegetative propagation . Naturally, these storage organs are sink tissues during the active growth cycle of the plant, but they turn into a source during vegetative propagation. Synchronized dormancy and sprouting with the environment are crucial for plant fitness and maximum yield. The active metabolic status of an underground vegetative organ determines its developmental fate. Sugars are the main components of storage organs; thus, their dynamics play an important role in controlling the dormancy-activity cycle of geophytes. Dormant buds require carbon sources (sugar) to promote growth, and the plant adjusts sugar metabolism between storage and soluble sugars to maintain dormancy and sprouting. In recent years, sugars and their derivatives, besides energy molecules, have also been considered signaling molecules involved in several plant developmental processes, including vegetative dormancy and growth. This review discusses current knowledge on the role of sugars in regulating and controlling dormancy and sprouting in geophytes. It’s regulation by external environmental factors, hormonal regulation and cross-talk. It also outlines how similar or different the regulatory mechanism controlling geophyte dormancy and sprouting is, compared to seed dormancy and germination and seasonal/annual growth in perennials that undergo dormancy-activity cycles. • The role of sugars in controlling dormancy and sprouting has been discussed in this review.. • Sugars, type and metabolism, differ in different storage organs in geophytes. • External and internal factors tune sugar metabolism differently during dormancy. • A similar yet divergent mechanism is involved in above/below ground organ dormancy-sprouting regulation.

Dietary Influences on Gut Microbiota with a Focus on Metabolic Syndrome.

There is a clear correlation between gut microbiota, diet, and metabolic outcomes. A diet high in fiber has been shown to decrease inflammation, increase insulin sensitivity, and reduce dyslipidemias whereas a diet high in fat and sugar leads to dyslipidemia, insulin resistance, and low-grade inflammation. There is recent evidence suggesting that the human gut microbiota has a significant role in the development or the resolution of metabolic syndrome (MetS) and associated conditions. Leading a stressful, sedentary lifestyle with limited or no physical activity and consuming an unhealthy diet high in saturated fat, simple carbohydrates, and sodium and low in dietary fiber and in high-quality protein are some of the contributing factors. Unhealthy diets have been shown to induce alterations in the gut microbiota and contribute to the pathogenesis of MetS by altering microbiota composition and disrupting the intestinal barrier, which leads to low-grade systemic inflammation. In contrast, healthy diets can lead to changes in microbiota that increase gut barrier function and increase the production of anti-inflammatory biomarkers. This review aims at providing a more in-depth discussion of diet-induced dysbiosis of the gut microbiota and its effect on MetS. Here, we discuss the possible mechanisms involved in the development of the metabolic biomarkers that define MetS, with an emphasis on the role of sugar and dietary fiber in microbiome-mediated changes in low-grade systemic inflammation and metabolic dysfunction.

Effects of sugar addition on adipolysis and volatile profiles of dry cured sausage

As sugar play a primary role in food flavor and biochemical reaction during the industrial manufacture of dry cured meat products, we aim to evaluate the function of sugar and how the quality changed with the addition of sugar on dry cured sausage after three months of preservation, and the corresponding effect on acidity value and the total acid value. The roles of sugars’ effects on FA hydrolysis and flavor formation are required to be assessed. We selected the addition of sugar with the gradient contents from 3% to 15%, we found that the total acid, acidity value, peroxide value, FA and organic acid were significantly affected. Mono unsaturated fatty acids (MUFA) was the main content of FAs, following by saturated FA and polyunsaturated FA. C 18:1n9c was the major FA, following by C 16:0 and C 18:0 . Six kinds of organic acids in dry-cured sausages containing different concentrations of sugar were analyzed by HPLC and the total organic acid reached a maximum of 12.15% by after adding 6% sugar. Acetic acid was 8.06% and lactic acid was 2.56%. This study concludes that sugar is the main factor in flavor formation of dry cured sausage and affects the sausage quality for three months in storage.

Metabolism and Health Effects of Rare Sugars in a CACO-2/HepG2 Coculture Model.

Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease worldwide and is impacted by an unhealthy diet with excessive calories, although the role of sugars in NAFLD etiology remains largely unexplored. Rare sugars are natural sugars with alternative monomers and glycosidic bonds, which have attracted attention as sugar replacers due to developments in enzyme engineering and hence an increased availability. We studied the impact of (rare) sugars on energy production, liver cell physiology and gene expression in human intestinal colorectal adenocarcinoma (Caco-2) cells, hepatoma G2 (HepG2) liver cells and a coculture model with these cells. Fat accumulation was investigated in the presence of an oleic/palmitic acid mixture. Glucose, fructose and galactose, but not mannose, l-arabinose, xylose and ribose enhanced hepatic fat accumulation in a HepG2 monoculture. In the coculture model, there was a non-significant trend (p = 0.08) towards higher (20–55% increased) median fat accumulation with maltose, kojibiose and nigerose. In this coculture model, cellular energy production was increased by glucose, maltose, kojibiose and nigerose, but not by trehalose. Furthermore, glucose, fructose and l-arabinose affected gene expression in a sugar-specific way in coculture HepG2 cells. These findings indicate that sugars provide structure-specific effects on cellular energy production, hepatic fat accumulation and gene expression, suggesting a health potential for trehalose and l-arabinose, as well as a differential impact of sugars beyond the distinction of conventional and rare sugars.

Genotype influence on shelf life behaviour of minimal processed loquat (Eriobotrya japonica (Thunb.) Lindl.) fruit: the role of sugar, acid organics and phenolic compounds

BackgroundLoquat cultivars cultivated in Southern Italy are very appreciated by consumers for their sensorial characteristics, such as persistent aroma and taste. Apposite maturity indexes for peeling and processing loquat fruit were investigated to increase diffusion of minimally processed loquat. The genotype’s effect on the minimally processed loquat fruit shelf life and quality harvested at commercial maturity (80% yellow color) was investigated on peeled fruit stored at 5 °C for 10 days. The role of sugars, organic acids and phenols composition was observed through in depth qualitative analysis. In addition, several qualitative analyses were carried out to determine the quality of minimal processed fruit.ResultsLoquat fruits harvested at commercial ripening stage performed very good palatability and flesh color persistency. Late ripening fruits genotypes shown a low rate of pulp oxidation and quality decay, while early ripening fruits were not suitable for fresh-cut. Genotype had a great influence on weight loss, β-carotene content, fruit respiration, ascorbic acid and total phenols content during the shelf life.ConclusionsThis work shows how the amount of the composition of sugars and organic acids as an intrinsic characteristic of genotype influences the quality of loquat fruits minimal processed. The higher values of glucose, sorbitol and ascorbic acid accumulated in the cv ‘Nespolone Trabia’ contributed to a reduction in chilling injury and oxidative stress after cutting.Graphical

Sugar, salt and fat reduction of bakery products.

From the health viewpoint, consumers monitor their food uptake in terms of both quality and quantity, due to awareness of the link between food ingredients and health. Accordingly, many people tend to buy healthy food products that are low in or free of sugar, salt and fat. However, in baked products, the sugar, fat and salt are needed to create unique characteristics. The role of sugar, salt and fat in baked products is discussed in this chapter to understand their functions. The understanding is necessary to design proper techniques to reduce the amount of sugar, salt and fat. Ingredients and additives that can substitute for fat, sugar and salt in bakery characteristics are reviewed in terms of their advantages and disadvantages. In addition, alternative processes to reduce the use of fat, sugar and salt are proposed in this chapter.

Sweetening … the pain: The role of sugar in acutely prolapsed haemorrhoids.

Haemorrhoids are considered among the most frequent proctologi-cal condition at a general practitioner (GP) practice. Acute prolapse of internal haemorrhoids is presented with oedema, inflammation and acute pain. The application of granulated sugar on swollen hae-morrhoids leads to an immediate reduction of their edema and to the patient's relief. After the topical application of sugar, haemorrhoids begin to shrink immediately and edema is drastically reduced, while haemorrhoidal tissue can easily retracted back into the anal canal. The method is a cheap, quick and painless way to control the worsening symptoms such as swelling, bleeding and irritation. In addition, this method can easily be applied in the GP practice without the necessity of any form of anaesthesia.

The Role of Sugars in the Caries Process

The carious disease is a post-eruptive infectious pathology of the hard tissues of the tooth. It is the most common dental disease, with a prevalence of 60 to 90% in school children worldwide. It is a significant public health issue. The caries process involves cariogenic bacteria (mutans streptococci - lactobacilli), which, by metabolizing carbohydrates, produce acids that lower the pH of the oral cavity below a critical threshold and thus cause demineralization of the enamel.Indeed, the consumption of sugars and sweetened products is a known risk factor for caries induction. The most cariogenic sugars are the fast sugars, mainly sucrose, widely used in the food industry. In addition to the nature of the sugar, several other factors condition the appearance of caries disease, namely the quantity of sugar consumed, its consistency, the duration of its contact with the teeth, the time and frequency of its consumption.Among the pillars of caries prevention, the control of the frequency and timing of consumption is essential. If the eradication of free sugars remains challenging to apply, their consumption must be reduced. This article aims first to discuss the link between the different types of sugars and the caries process and then present the current recommendations for the consumption of sugars to prevent caries disease.

Molecular basis for optimizing sugar metabolism and transport during fruit development.

Sugars are fundamental metabolites synthesized in leaves and further delivered to fruit in fruit crops. They not only provide "sweetness" as fruit quality traits, but also function as signaling molecules to modulate the responses of fruit to environmental stimuli. Therefore, the understanding to the molecular basis for sugar metabolism and transport is crucial for improving fruit quality and dissecting responses to abiotic/biotic factors. Here, we provide a review for molecular components involved in sugar metabolism and transport, crosstalk with hormone signaling, and the roles of sugars in responses to abiotic and biotic stresses. Moreover, we also envisage the strategies for optimizing sugar metabolism during fruit quality maintenance.

Revealing floral metabolite network in tuberose that underpins scent volatiles synthesis, storage and emission.

The role of central carbon metabolism in the synthesis and emission of scent volatiles in tuberose flowers was revealed through measurement of changes in transcripts and metabolites levels. Tuberose or Agave amica (Medikus) Thiede & Govaerts is a widely cultivated ornamental plant in several subtropical countries. Little is known about metabolite networking involved in biosynthesis of specialized metabolites utilizing primary metabolites. In this study, metabolite profiling and gene expression analyses were carried out from six stages of maturation throughout floral lifespan. Multivariate analysis indicated distinction between early and late maturation stages. Further, the roles of sugars viz. sucrose, glucose and fructose in synthesis, glycosylation and emission of floral scent volatiles were studied. Transcript levels of an ABC G family transporter (picked up from the floral transcriptome) was in synchronization with terpene volatiles emission during the anthesis stage. A diversion from phenylpropanoid/benzenoid to flavonoid metabolism was observed as flowers mature. Further, it was suggested that this metabolic shift could be mediated by isoforms of 4-Coumarate-CoA ligase along with Myb308 transcription factor. Maximum glycosylation of floral scent volatiles was shown to occur at the late mature stage when emission declined, facilitating both storage and export from the floral tissues. Thus, this study provides an insight into floral scent volatiles synthesis, storage and emission by measuring changes at transcripts and metabolites levels in tuberose throughout floral lifespan.