Sugars Glucose Research Articles

From Waste to Taste: Coffee By-Products as Starter Cultures for Sustainable Fermentation and Improved Coffee Quality

Utilizing coffee by-products in the fermentation process of coffee offers a sustainable strategy by repurposing agricultural waste and enhancing product quality. This study evaluates the effect of applying a starter culture, derived from coffee residues, on the dynamics of reducing and total sugars during coffee fermentation, as well as the composition of aromatic compounds, organic acids, and the sensory profile of coffee inoculated with yeast (Saccharomyces cerevisiae) and lactic acid bacteria (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus), in comparison to a spontaneously fermented sample. Volatile compounds were identified and quantified using dynamic headspace gas chromatography-mass spectrometry (HS/GC-MS), with predominant detection of 2-furancarboxaldehyde, 5-methyl; 2-furanmethanol; and furfural—compounds associated with caramel, nut, and sweet aromas from the roasting process. A reduction in sugars (glucose, fructose, and sucrose) occurred over the 36 h fermentation period. Lactic acid (2.79 g/L) was the predominant organic acid, followed by acetic acid (0.69 g/L). The application of the inoculum improved the sensory quality of the coffee, achieving a score of 86.6 in evaluations by Q-graders, compared to 84 for the control sample. Additionally, descriptors such as red apple, honey, and citrus were prominent, contributing to a uniform and balanced flavor profile. These findings indicate that controlled fermentation with starter cultures derived from coffee by-products enhances sustainability in coffee production. It achieves this by supporting a circular economy, reducing reliance on chemical additives, and improving product quality. This approach aligns with sustainable development goals by promoting environmental stewardship, economic viability, and social well-being within the coffee industry.

Improving flavor of strong fragrant rapeseed oils by supplementing commercial peptides and sugars

The strong fragrant rapeseed oils (SFROs) attract an increasing consumers' preference due to their strong flavor and attractive appearance. With the accumulated knowledge of flavor formation pathways during producing SFROs, the present study proposed a novel method to enhance SFRO's flavor by directly adding the reducing sugars (glucose and xylose) and commercial peptides during roasting process. Results indicated that supplementation of 3 % rapeseed peptide, 1 % glucose and 0.5 % of xylose gave an attractive color of SFRO with highest red value of 6.5, highest sensory score, enhanced nutty and roasted fragrance and distinguishing sweet flavor. The contents of typical volatile compounds such as pyrazines and furans in R-SFRO also showed the highest levels, proving that addition of the commercial peptide and reducing sugars as the Maillard reaction substrates could significantly enhance the flavor. Additionally, the proposed method showed potency for the large-scale application due to the simple steps, and low-cost input.

Analysis on density of states and ION/IOFF ratio of GaN/GaN-graphene nanoribbon tunnel FET for enhanced bio-sensing applications

Abstract This research introduces a new analytical model that studies the effect of ferro-dielectric on the operational performance of TFETs doped with halogens. The effect of source and drain depletions, voltage-drain & gate, thickness and capacitance of gate insulator are all investigated in this study. Accurate measurements of the surface potential are required to ascertain the transconductance, gate-to-drain capacitance, and lateral electric field of the device. Our model, which employs Ferroelectric Halo-Doped double gate (FHDD)-gated device designs, has been demonstrated to produce results that nearly match those produced from TCAD simulations. This was accomplished by doing a comparative analysis of the outcomes derived from both sets of simulations. Furthermore, the performance of the suggested structure of TFET, which integrates a dielectric of Fe and GaN heterostructure, surpasses that of other similar devices (fT) in terms of ON current, ON/OFF ratio, transconductance, and cut-off frequency. A ferroelectric dielectric was used to create a ferroelectric heterostructure. This study also centers on the creation and application of a graphene nanoribbon field effect transistor (GNR-TFET) to detect sugar molecules, specifically fructose, xylose, and glucose. The detecting signal is generated by utilizing the fluctuation in the electrical current of the GNR-TFET caused by the presence of individual sugar molecules. The GNR-TFET exhibits noticeable variations in the density of states, transmission spectrum, and current when exposed to individual sugar molecules. The sensor under investigation is being developed and examined using a combination of semi-empirical modeling and non-equilibrium Green's functional theory (SE + NEGF). According to the research, the modified GNR TFET has the ability to quickly and accurately detect individual sugar molecules in real-time.

Genetic and QTL analysis of sugars and acids content in sweet cherry (Prunus avium L.)

Abstract Sweet cherry is very appreciated by consumers because of its attractive appearance and taste, which is determined by the balanced sweet-sour flavor. In this work, the genetics of soluble solid content (SSC), titratable acidity (TA), sugars and organic acids was investigated in sweet cherry to facilitate breeding improvement for fruit quality. The fruits of five sweet cherry populations (N = 372), three F1 and two F2, were sampled over two years to evaluate SSC, TA, and the content of individual sugars (glucose, fructose, sorbitol, and sucrose) and organic acids (malic, quinic, oxalic, citric and shikimic) by ultra-performance liquid chromatography (UPLC). Glucose, followed by fructose, was the most abundant sugar, while malic acid was the predominant acid. Sorbitol and malic acid were the most stable compounds between years, and had the highest heritability, being also the best correlated to SSC and TA respectively, revealing their relevance for breeding. Significantly positive correlations were observed among sugars and SSC, and acids and TA, but high interannual variability between years was observed for all traits. QTL mapping for SSC, sugars, TA, and organic acids was performed using a multi-family approach with FlexQTL™. Twenty QTLs were detected consistently during the two phenotyped years, and several relevant regions with overlapping QTLs for sugars and acids were also identified. The results confirmed major stable SSC and TA QTLs on the linkage groups 4 and 6, respectively. Within the main LG4 SSC QTL region, where maturity and fruit development time QTLs have been previously detected, three stable sugar (glucose, sorbitol, and sucrose) and two acid (quinic, shikimic) QTLs were also identified, suggesting a pleiotropic effect of ripening date on the content of these compounds. The major malic acid QTL overlapped with TA QTL on LG6, thus TA QTL mapping in LG6 may correspond to malic acid QTLs. Haplotype analyses of major SSC and sugars QTL in LG4, and TA and malic acid in LG6 revealed haplotypes of breeding interest. Several candidate genes previously identified in other Prunus fruit species, like peach, were found to collocate with the QTLs detected herein. This work reports QTLs regions and haplotypes of sugar and acid content in a Prunus non-climacteric stone fruit for the first time.

Overexpression of Cassava MeSTP7 Promotes Arabidopsis Seedling Development.

The sugar transporter (STP) gene family is a key regulator of plant development, which is crucial for the efficient transport and utilization of sugars during plant growth and development. In this study, we identified the MeSTP7 gene, which is highly expressed in cassava fibrous roots, early storage roots, and under hormonal treatment, including IAA, MeJA, ABA, and GA3, and abiotic stressors, such as mannitol and NaCl. A strong response was observed with exoqenous IAA. Transfecting MeSTP7 into Arabidopsis promoted early seedling growth, particularly in lateral root development. The content of endogenous hormones (IAA and MeJA) as well as soluble sugars (sucrose, fructose, and glucose) was elevated in transgenic Arabidopsis. Hormone treatments with IAA, MeJA, GA3, and ABA on transgenic Arabidopsis revealed that transgenic Arabidopsis responded positively to added 20 μM IAA. They also exhibited co-induced regulation of lateral root formation by GA3, MeJA, and ABA. qRT-PCR analysis showed that overexpression of MeSTP7 upregulated the expression of IAA14, ARF7, and ARF19 in Arabidopsis. Under IAA treatment, the expression of these genes was similarly upregulated but downregulated under MeJA treatment. These results suggest that MeSTP7 may promote Arabidopsis seedling development by increasing the content of sucrose, glucose, and fructose in roots, which in turn influences IAA-based hormonal signaling.

The production of D-lactic acid by fermentation from the waste newspapers recycling as the carbon source

D-lactic acid (D-LA) is an important substance, which has been used in various end-use industries, including pharmaceuticals, food and milk beverages. Lignocellulose is a desirable material for D-LA fermentation, due to its hydrolysate rich in monosaccharides can be obtained from the wastes to finally achieve high D-lactate yields. In this study, the waste newspapers removed most of the lignin was applied as a carbon source to produce D-LA using Escherichia coli JH15, rice straw hydrolysate and mixed sugars (glucose and xylose) were selected as a control. Compared with rice straw hydrolysate, the waste newspapers hydrolysate as a carbon source for D-LA production has obvious advantages, including high D-LA concentration, fast fermentation speed and no need for detoxified treatment. Compared to the mixed sugars, the D-LA productivity and conversion yield of total sugars to D-LA did not been different significantly using waste newspapers hydrolysate as a fermentation substrate, but the fermentation duration was extended by 6 hours. The fermentation could be finished just after 16 hours in a 7-L fermenter, and the maximum concentration of D-LA reached 33.60 g/L, with a high conversion yield of total sugars to D-LA (0.92 g/g). According to the fermentation performances of the concentration of D-LA, the yield of D-LA, the conversion yield of total sugars to D-LA, the fermentation duration, the waste newspapers hydrolysate as a carbon source for D-LA production is an efficient strategy to enhance the economic feasibility of this bioprocess.

Optimization of microwave-assisted hydrolysis of glucose from oil palm empty fruit bunch

Hydrolysis of oil palm empty fruit bunches (OPEFB) using microwave as an energy source is carried out to produce sugar with mild operating conditions. One way to find the best conditions that can obtain high-quality sugar is to optimize the hydrolysis process. In this study, optimization was carried out using Response Surface Methodology (RSM) with a Central Composite Design (CCD) experimental design. Estimated variables to affect the hydrolysis process are the ratio of OPEFB to solvent (X1: 1:20–4:20 g/ml), solvent concentration (X2: 0.5–1.5 %), and hydrolysis time (X3: 5–15 min). Hydrolysis success parameters were measured by hydrolysis temperature (Y1), glucose (Y2), fructose (Y3), and total sugar (Y4) concentration. The optimization results show that the three independent variables contribute 53.25 % to the hydrolysis temperature and 86.42 % to the sugar concentration. The recommended operating conditions were hydrolysis with the ratio of OPEFB to solvent of 4:20 g/ml, solvent concentration of 0.5 %, and carried out for 10 min. The hydrolysis temperature cannot be optimized because there is a mismatch in the temperature model analysis. The application of these conditions is predicted to produce glucose, fructose, and total sugar of 315.51; 258.24; 573.85 mg/L respectively. The last step is to validate these conditions in the laboratory to get the actual value. Actual glucose, fructose, and total sugar obtained were 300.40; 245.44; 545.84 mg/L respectively. The error in this study is less than 5 % which indicates the actual value is following the predicted value. © 2001 Elsevier Science. All rights reserved.

Mapping Natural Sugars Metabolism in Acute Myeloid Leukaemia Using 2D Nuclear Magnetic Resonance Spectroscopy.

Metabolism plays a central role in cancer progression. Rewiring glucose metabolism is essential for fulfilling the high energy and biosynthetic demands as well as for the development of drug resistance. Nevertheless, the role of other diet-abundant natural sugars is not fully understood. In this study, we performed a comprehensive 2D NMR spectroscopy tracer-based assay with a panel of 13C-labelled sugars (glucose, fructose, galactose, mannose and xylose). We assigned over 100 NMR signals from metabolites derived from each sugar and mapped them to metabolic pathways, uncovering two novel findings. First, we demonstrated that mannose has a semi-identical metabolic profile to that of glucose with similar label incorporation patterns. Second, next to the known role of fructose in driving one-carbon metabolism, we explained the equally important contribution of galactose to this pathway. Interestingly, we demonstrated that cells growing with either fructose or galactose became less sensitive to certain one-carbon metabolism inhibitors such as 5-Flurouracil and SHIN1. In summary, this study presents the differential metabolism of natural sugars, demonstrating that mannose has a comparable profile to that of glucose. Conversely, galactose and fructose contribute to a greater extent to one-carbon metabolism, which makes them important modulators for inhibitors targeting this pathway. To our knowledge, this is the first NMR study to comprehensively investigate the metabolism of key natural sugars in AML and cancer.

Unveiling a novel exopolysaccharide produced by Pseudomonas alcaligenes Med1 isolated from a Chilean hot spring as biotechnological additive

Exopolysaccharides (EPSs), a constitutive part of bacterial biofilm, act as a protecting sheath to the extremophilic bacteria and are of high industrial value. In this study, we elucidate a new EPS produced by thermotolerant (growth from 34–44 °C) strain Pseudomonas alcaligenes Med1 from Medano hot spring (39.1 °C surface temperature, pH 7.1) located in the Central Andean Mountains of Chile. Bacterial growth was screened for temperature tolerance (10–60 °C) to confirm the thermotolerance behaviour. Physicochemical properties of the EPS were characterized by different techniques: Scanning Electron Microscopy- Energy Dispersive X-ray Spectroscopy (SEM-EDS), Atomic Force Microscopy (AFM), High-Performance Liquid Chromatography (HPLC), Gel permeation chromatography (GPC), Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), and Thermogravimetric analysis (TGA). Whole genome of P. alcaligenes Med1 has also been studied in detail to correlate the structural and functional characteristics with genomic insight. The EPS demonstrated amorphous surface roughness composed of evenly distributed macromolecular lumps composed of mainly carbon and oxygen. The monosaccharide analysis has shown the presence of glucose, galactose, and mannose sugars at different ratios. TGA revealed the high thermal stability (315.3 °C) of the polysaccharide. The GPC has shown that Med1 is a low molecular weight polysaccharide (34.8 kDa) with low PI. The 2D-NMR linkage analysis suggests a diverse array of glycosidic bonds within the exopolysaccharide structure. The functional properties of the EPS were evaluated for food industry applications, specifically for antioxidant (DPPH, FRAP an H2O2). Extracted Med1 EPS revealed significant emulsification activity against different food grade vegetative oils (Coconut oil, Corn oil, Canola oil, Avocado oil, Sunflower oil, Olive oil, and Sesame oil). The highest 33.9% flocculation activity was observed with 60 mg L−1 EPS concentration. It showed water-holding (WHC) of 107.6% and oil-holding (OHC) capacity of 110.8%. The functional EPS produced by Pseudomonas alcaligenes Med1 from Central Andean Chilean hot spring of central Chile can be a useful additive for the food-processing industry.

Modulation of gut microbiome in response to the combination of Escherichia coli Nissle 1917 and sugars: a pilot study using host-free system reflecting impact on interpersonal microbiome.

The differential effects of probiotic, prebiotic, and synbiotic formulations on human health are dictated by the inter-individual gut microbial profile. The effects of probiotics such as Escherichia coli Nissle 1917 (ECN) on gut microbiota may vary according to the microbiome profiles of individuals and may be influenced by the presence of certain carbohydrates, which can impact microbial community structure and treatment results. Processed fecal samples from donors having contrasting lifestyles, dietary patterns, and disease histories were mixed with 5 × 106 CFU/mL ECN with or without 1% (w/v) sugars (glucose, galactose, or rice starch) in a host-free system. Post-incubation, 16 s rRNA sequencing was performed. Microbial diversity and taxonomic abundance were computed in relation to the probiotic, prebiotic, and synbiotic treatment effects and interpersonal microbiome variance. Baseline gut microbial profiles showed significant inter-individual variations. ECN treatment alone had a limited impact on the inter-personal gut microbial diversity and abundance. Prebiotics caused a substantial enrichment in Actinobacteria, but there were differences in the responses at the order and genus levels, with enrichment shown in Bifidobacterium, Collinsella, and Megasphaera. Subject B exhibited enrichment in Proteobacteria and Cyanobacteria, but subject A showed more diversified taxonomic alterations as a consequence of the synbiotic treatments. Despite negligible difference in the α-diversity, probiotic, prebiotic, and synbiotic treatments independently resulted in distinct segregation in microbial communities at the β-diversity level. The core microbiota was altered only under prebiotic and synbiotic treatment. Significant correlations primarily for minor phyla were identified under prebiotic and synbiotic treatment. The interindividual microbiome composition strongly influences the effectiveness of personalized diet and treatment plans. The responsiveness to dietary strategies varies according to individual microbiome profiles influenced by health, diet, and lifestyle. Therefore, tailored approaches that consider individual microbiome compositions are crucial for maximizing gut health and treatment results.

Sugar inclusion influences the expansion characteristics of corn starch extrudates.

Corn starch-based direct expanded products incorporated with 2% and 10% (w/w) sugar (fructose, glucose, sucrose, and xylose) were produced using a 20mm co-rotating twin-screw extruder. The pasting and thermal properties of raw corn starch-sugar mixes were analyzed before extrusion processing. The independent variables for extrusion processing included two sugar inclusion levels (2% and 10% w/w) and two screw speeds (150 and 250rpm). The extrudates were characterized by their initial expansion ratio (IER), expansion ratio (ER), and shrinkage. ER values were high for fructose at 2% and 150rpm and 10% glucose and sucrose extrudates at 250rpm. The extrudates with 2% sucrose inclusion shrunk significantly higher than the control. Fourier transform infrared (FTIR) spectroscopy of the extruded blends did not indicate the presence of any new covalent bond formed between starch and sugar post-extrusion. The interactions between sugar concentration and screw speed significantly influenced extrudate expansion characteristics. Due to their thermal and plasticizing properties, sugar inclusion (glucose, fructose, sucrose, and xylose) enhanced the extrudate expansion by altering their melt viscosity. PRACTICAL APPLICATION: The findings of this study can improve the expansion characteristics of high-fiber-based extruded snacks. Ingredients high in fiber generally hinder the starch transformation during extrusion and negatively impact the expansion properties. The presence of sugar at low concentrations can improve melt properties during extrusion processing and, in turn, significantly improve the textural properties of snacks.

Nutrient content and ultra-performance liquid chromatography tandem mass spectrometry metabolomic comparative analysis of Lithocarpus corneus and Lithocarpus pachylepis.

China possesses abundant species resources in genus Lithocarpus Blume, commonly known as "acorns." These nuts are traditional foods in China, holding significant potential for local specialty food and rural economic development. To explore their edible value, we compared the nutritional components and metabolites between the fruits of Lithocarpus corneus (YD) and Lithocarpus pachylepis (HL), which are cultivated widely in south of China. Non-targeted metabolomics analysis of YD and HL was performed using ultra-performance liquid chromatography tandem mass spectrometry technology. A total of eight classes of differential metabolites (DAMs) were detected: alkaloids, amino acids and peptides, carbohydrates, fatty acids, polyketides, shikimates and phenylpropanoids, terpenoids, and other metabolites. In the positive ion mode, 225 DAMs were identified, whereas in the negative ion mode, 116 DAMs were identified. KEGG pathway enrichment analysis showed that the differentially abundant metabolites were generally enriched in three pathways: aminoacyl-tRNA biosynthesis, alanine, aspartate, and glutamate metabolism, and ABC transporters. The nutritional content of YD has higher moisture, fructose, and total flavonoid levels, but lower starch, protein, fat, glucose, sucrose, and total sugar content than HL. Additionally, YD contains more Ca, K, P, and Fe, but less Mg and Zn compared to HL. Analyses indicate that YD is nutrient-rich and beneficial, making it suitable for further development. Two species of Lithocarpus contain nandrolone, suggesting a new direction for specialty food development. The unique chemical composition and rich nutritional content of Lithocarpus fruits provide a theoretical basis for their development and application as food resources. PRACTICAL APPLICATION: L. corneus and L. pachylepis are traditional Chinese nuts, rich in starch, minerals, and flavonoids, making them suitable for consumption or use as food constituents. Their fruits contain various unique natural chemical compounds, indicating high application value and development potential.

Optimization of Sugar Extraction Process from Date Waste Using Full Factorial Design Toward Its Use for New Biotechnological Applications.

In Tunisia, the date industry generates a large quantity of waste, raising environmental concerns. However, dates are rich in sugars, which offer a renewable source of nutrients for various applications. In this study, sugar extraction from two low-grade pitted date fruits (Alig and Kentichi) under ultrasound, was optimized using full factorial design. At 40 °C, for20 min, and with a liquid-to-solid ratio of 10 mL/g, the optimum sugar contents were 60.87% and 50.79% for the varieties Alig and Kentichi, respectively. The date extracts were chemically analyzed, revealing low fat and protein contents, but significant polyphenol and mineral contents in both varieties. HPLC-IR analysis revealed more inverted sugars (glucose and fructose) in the Alig variety and more sucrose in the Kentichi variety. FTIR and SEM analysis showed the efficiency of the ultrasonic treatment of the biomass in terms of improving mass transfer diffusion through ultrasonic cavitation. Thus, ultrasound-assisted extraction constitutes an effective method for the recovery of sugar from date waste.

Physicochemical and bioactive modifications of lotus root polysaccharides associated with probiotic fermentation

The physicochemical properties and bioactivities of lotus root polysaccharides (LRP) were investigated by examining the effects of probiotic fermentation. Five polysaccharides, namely LRP, LRP-Pl, LRPRh, LRPPa, and LRPAc, were extracted from unfermented and fermented lotus roots using Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus paracasei and Lactobacillus acidophilus, respectively. The results revealed that the yield of LRP-Ac (3.28 %) was 3.34 times higher than that of LRP (0.98 %), with its total sugar content and glucose content in the monosaccharide composition being the highest among the five polysaccharides. Probiotic fermentation led to an increase in Mw, as well as alterations in surface morphology and glycosidic bonds of LRPs, depending on the bacterial strains. Moreover, the five polysaccharides showed differences in antioxidant, α-amylase/α-glucosidase inhibitory, prebiotic, and macrophage-stimulating activities. Specifically, LRP-Pl exhibited the strongest DPPH radical scavenging ability; LRP-Rh showed the highest ABTS radical scavenging ability along with FRAP capacities; LRP-Ac possessed the greatest α-glucosidase inhibitory as well as prebiotic activities. However, the fermented polysaccharides showed relatively weak macrophage-stimulating ability compared to unfermented ones. Finally, the structure-activity relationship analysis revealed a close correlation between the chemical composition, Mw, and monosaccharide composition of LRPs and their bioactivities. These results are useful for the preparation of high-value LRPs.

Analysis Of Chemical Components And Reducing Sugar Content In Popular Energy Drinks In Nigeria: A Comprehensive Study

The study undertook a thorough examination of the chemical components present in soft drinks, focusing particularly on popular energy drink brands in Nigeria and their potential health effects using established chemical analysis techniques. All the sampled soft drinks exhibited acidity attributed to acidic preservatives, with pH levels ranging from 2.78 to 3.28, impacting both taste and shelf life. The Lane and Eynon titration method was employed to determine sugar content, revealing the presence of both reducing sugars (glucose, fructose) and non-reducing sugars (sucrose), which ranged from 15.28 to 23.71 g/100 ml. Energy drinks, notable for their higher caffeine content to counteract bitterness, were found to contain caffeine levels ranging from 325.11 to 405.12 mg/L, measured using UV-visible spectrophotometry. Thin-layer chromatography identified synthetic food colorants across different drinks, which serve to enhance visual appeal and influence consumer perception. The study underscores the importance of consumer awareness regarding the chemical composition of soft drinks, particularly energy drinks, and their potential health implications.

Comparison of Classification Results of SVM, KNN, Decision Tree, and Ensemble Methods in Diabetes Diagnosis

This study aims to determine which algorithms and test techniques are the most optimal in detecting diabetes mellitus and obtaining the best results based on the value of accuracy, precision, and recall. In this study, approaches were used in early diagnosis of diabetes using KNN, SVM, Decision Tree, and Ensemble Majority Voting methods in Percentage Split and K-Fold Cross Validation methods. Diabetes is a disease characterized by high blood sugar (glucose) levels and can cause a variety of disease complications and damage to the body's organs if not treated immediately. Early diagnosis of diabetes is becoming crucial so that people can take immediate action to the hospital for immediate treatment. The data used is Healthcare-Diabetes from Kaggle. The results of this study have found that the K-Fold Cross Validation method is better because it can provide an average improvement in Ensemble accuracy of 13.42% compared to the Percentage Split method which only gives an average increase in Ensamble accuracy of 9.15%. The best algorithm for classifying diabetes disease is the Ensemble Majority Voting algorithm using the K-Fold Cross Validation method with a 98.81% accuracy rate. These excellent research results may contribute to detecting early symptoms of diabetes before it become too severe.

Dynamic Analysis of the Fruit Sugar-Acid Profile in a Fresh-Sweet Mutant and Wild Type in 'Shatangju' (Citrus reticulata cv.).

Citrate is a major determinant of fruit flavor quality. Currently, citrus species and/or varieties with significant alterations in citrate level have greatly advanced the molecular basis of citrate accumulation in fruit. However, in-depth dissections of the molecular mechanism specific to citrate accumulation are still limited due to the lack of mutants, especially within one single variety. In this study, a fresh-sweet 'Shatangju' mutant (Citrus reticulata cv.) was obtained during a survey of citrus resources in Guangdong, China, and the phenotype, fruit morphology, and primary flavor profiles were comparatively analyzed. Unlike the wild-type 'Shatangju' (WT), the mutant (MT) material exhibited a dwarfed and multi-branched tree shape, delayed flowering and fruit ripening at maturity, a prolonged fruit tree-retention time, and a decreased single fruit weight at maturity. Dynamic measurement of the metabolite levels further suggested that the contents and fluctuation patterns of vitamin C, malate, quinate, and oxalate showed no obvious difference between MT and MT fruits, while the citrate level in MT fruits significantly decreased over various developmental stages, ranging from 0.356 to 1.91 mg g-1 FW. In addition, the accumulation patterns of the major soluble sugars (sucrose, fructose, and glucose), as well as the sugar/acid ratio, were also altered in MT fruits during development. Taken together, this study provides a novel acid-free 'Shatangju' mutant, which can serve as a powerful tool for the research of fruit flavor quality, especially for the comprehensive understanding of the molecular mechanism of citrate accumulation in fruits.

Hydrogen-rich solvent method enhances the extraction of phenolics, pigments, reducing sugars, organic acids, and vitamin C from cowslip (Primula veris L.) flower

Cowslip (Primula veris L.) is an anioxidant-rich plant used for many food and medicinal purposes. In this study, the effect of incorporating hydrogen (H2) into water (HRW), ethanol (HRE), and methanol (HRM) on the extraction of flavonoids (TFC), phenolics (TPC), and antioxidants (metal chelation, FRAP, DPPH, and ABTS) as well as color (L*, a*, b*, C*, H°), chlorophyll (a, b), lycopene, and β-carotene of wild cowslip flowers was evaluated. The results were submitted to Principal Component Analysis and correlation. Phenolic compounds, organic acids, vitamin C, and sugar content of the extract were analyzed using high-performance reverse phase liquid chromatography (HPLC-DAD/RID). The highest TPC, TFC, and antioxidant activity (metal chelation, FRAP, DPPH, and ABTS) were shown for HRM samples, followed by HRE samples, while the lowest were found for pure solvents. Incorporating H2 into all solvents significantly increased TPC, TFC, metal chelation, DPPH, and ABTS scavenging activity, as well as b*, C*, H°, chlorophyll, lycopene, and β-carotene values. The levels of some phenolics (catechin, epicatechin, rutin, and quercetin), organic acids (tartaric acid and succinic acid), reducing sugars (maltose, glucose, and fructose), and ascorbic acid increased by 10–90 % when an H2-rich solvent was used instead of the pure solvent. This is the first report showing the enhanced extraction of organic acids, pigments, and ascorbic acid by hydrogen-rich solvent. The main benefits of the HRS method are its sustainability and high efficiency in extracting bioactive compounds from medicinal plants.

Transcriptome Analysis Reveals the Mechanism of Cold-Induced Sweetening in Chestnut during Cold Storage.

Chestnuts become sweetened with better tastes for fried products after cold storage, but the possible mechanism is not clear. The dynamics of sugar components and related physiological responses, as well as the possible molecular mechanism in chestnuts during cold storage, were investigated. Sucrose accumulation and starch degradation contributed to taste improvement. Sucrose content reached the peak after two months of cold storage, along with the accumulation of reducing sugars of maltose, fructose and glucose to a much lesser extent. Meanwhile, alpha-amylase and beta-amylase maintained high levels, and the activities of acid invertase and sucrose synthase increased. Transcriptome data demonstrated that differentially expressed genes (DEGs) were significantly enriched in the process of starch and sucrose metabolism pathway, revealing the conversion promotion of starch to sucrose. Furthermore, DEGs involved in multiple phytohormone biosynthesis and signal transduction, as well as the transcription regulators, indicated that sucrose accumulation might be interconnected with the dormancy release of chestnuts, with over 90% germinated after two months of cold storage. Altogether, the results indicated that cold storage improved the taste of chestnuts mainly due to sucrose accumulation induced by DEGs of starch and sucrose metabolism pathway in this period, and the sweetening process was interconnected with dormancy release.

Insights into malaria vectors–plant interaction in a dryland ecosystem

Improved understanding of mosquito–plant feeding interactions can reveal insights into the ecological dynamics of pathogen transmission. In wild malaria vectors Anopheles gambiae s.l. and An. funestus group surveyed in selected dryland ecosystems of Kenya, we found a low level of plant feeding (2.8%) using biochemical cold anthrone test but uncovered 14-fold (41%) higher rate via DNA barcoding targeting the chloroplast rbcL gene. Plasmodium falciparum positivity was associated with either reduced or increased total sugar levels and varied by mosquito species. Gut analysis revealed the mosquitoes to frequently feed on acacia plants (~ 89%) (mainly Vachellia tortilis) in the family Fabaceae. Chemical analysis revealed 1-octen-3-ol (29.9%) as the dominant mosquito attractant, and the sugars glucose, sucrose, fructose, talose and inositol enriched in the vegetative parts, of acacia plants. Nutritional analysis of An. longipalpis C with high plant feeding rates detected fewer sugars (glucose, talose, fructose) compared to acacia plants. These results demonstrate (i) the sensitivity of DNA barcoding to detect plant feeding in malaria vectors, (ii) Plasmodium infection status affects energetic reserves of wild anopheline vectors and (iii) nutrient content and olfactory cues likely represent potent correlates of acacia preferred as a host plant by diverse malaria vectors. The results have relevance in the development of odor-bait control strategies including attractive targeted sugar-baits.