Systems biology of electrogenic Pseudomonas putida - multi-omics insights and metabolic engineering for enhanced 2-ketogluconate production.

BACKGROUND: Pseudomonas putida KT2440 has emerged as a promising host for industrial bioproduction. However, its strictly aerobic nature limits the scope of applications. Remarkably, this microbe exhibits high bioconversion efficiency when cultured in an anoxic bio-electrochemical system (BES), where the anode serves as the terminal electron acceptor instead of oxygen. This environment facilitates the synthesis of commercially attractive chemicals, including 2-ketogluconate (2KG). To better understand this interesting electrogenic phenotype, we studied the BES-cultured strain on a systems level through multi-omics analysis. Inspired by our findings, we constructed novel mutants aimed at improving 2KG production. RESULTS: When incubated on glucose, P. putida KT2440 did not grow but produced significant amounts of 2KG, along with minor amounts of gluconate, acetate, pyruvate, succinate, and lactate. 13C tracer studies demonstrated that these products are partially derived from biomass carbon, involving proteins and lipids. Over time, the cells exhibited global changes on both the transcriptomic and proteomic levels, including the shutdown of translation and cell motility, likely to conserve energy. These adaptations enabled the cells to maintain significant metabolic activity for several weeks. Acetate formation was shown to contribute to energy supply. Mutants deficient in acetate production demonstrated superior 2KG production in terms of titer, yield, and productivity. The ∆aldBI ∆aldBII double deletion mutant performed best, accumulating 2KG at twice the rate of the wild type and with an increased yield (0.96 mol/mol). CONCLUSIONS: By integrating transcriptomic, proteomic, and metabolomic analyses, this work provides the first systems biology insight into the electrogenic phenotype of P. putida KT2440. Adaptation to anoxic-electrogenic conditions involved coordinated changes in energy metabolism, enabling cells to sustain metabolic activity for extended periods. The metabolically engineered mutants are promising for enhanced 2KG production under these conditions. The attenuation of acetate synthesis represents the first systems biology-informed metabolic engineering strategy for enhanced 2KG production in P. putida. This non-growth anoxic-electrogenic mode expands our understanding of the interplay between growth, glucose phosphorylation, and glucose oxidation into gluconate and 2KG in P. putida.

How carbon sources drive cellulose synthesis in two Komagataeibacter xylinus strains.

Bacterial cellulose synthesis from defined media and waste products has attracted increasing interest in the circular economy context for sustainable productions. In this study, a glucose dehydrogenase-deficient Δgdh K2G30 strain of Komagataeibacter xylinus was obtained from the parental wild type through homologous recombination. Both strains were grown in defined substrates and cheese whey as an agri-food waste to assess the effect of gene silencing on bacterial cellulose synthesis and carbon source metabolism. Wild type K2G30 boasted higher bacterial cellulose yields when grown in ethanol-based medium and cheese whey, although showing an overall higher D-gluconic acid synthesis. Conversely, the mutant Δgdh strain preferred D-fructose, D-mannitol, and glycerol to boost bacterial cellulose production, while displaying higher substrate consumption rates and a lower D-gluconic acid synthesis. This study provides an in-depth investigation of two K. xylinus strains, unravelling their suitability for scale-up BC production.

Modulation of acid-induced pea protein gels by gellan gum and glucono-δ-lactone: Rheological and microstructural insights.

This study investigated the effect of gellan gum (GG) and glucono-δ-lactone (GDL) on the acid-induced gel properties of pea protein isolate (PPI) pretreated with media milling. The inclusion of GG substantially enhanced the gel hardness of PPI gel from 18.69 g to 792.47 g though slightly reduced its water holding capacity (WHC). Rheological analysis showed that GG increased storage modulus (G') and decreased damping factor of gels in the small amplitude oscillatory shear region and transformed its strain thinning behavior into weak strain overshoot behavior in the large amplitude oscillatory shear region. SEM revealed that GG transformed the microstructure of gel from a uniform particle aggregate structure to a chain-like architecture composed of filaments with small protein particles attached. Turbidity and zeta potential analysis showed that GG promoted the transformation of PPI from a soluble polymer system to an insoluble coagulant during acidification. When GG content was relatively high (0.2 %-0.3 %), high GDL content increased the electrostatic interaction between PPI and GG molecules, causing their rapid aggregation into a dense irregular aggregate structure, further enhancing gel strength and WHC. Overall, GG and GDL can offer the opportunity to modulate the microstructure and gel properties of acid-induced PPI gels, presenting potential for diversifying food gel design strategies through PPI-GG hybrid systems.

Genomic insights into organic acid production and plant growth promotion by different species of phosphate-solubilizing bacteria.

Bacteria can solubilize phosphorus (P) through the secretion of low-molecular-weight organic acids and acidification. However, the genes involved in the production of these organic acids are poorly understood. The objectives of this study were to verify the calcium phosphate solubilization and the production of low-molecular-weight organic acids by diverse genera of phosphate solubilizing bacterial strains (PSBS); to identify the genes related to the synthesis of the organic acids in the genomes of these strains and; to evaluate growth and nutrient accumulation of maize plants inoculated with PSBS and fertilized with Bayóvar rock phosphate. Genomic DNA was extracted for strain identification and annotation of genes related to the organic acids production. A greenhouse experiment was performed with five strains plus 150 mg dm- 3 P2O5 as Bayóvar rock phosphate (BRP) to assess phosphate solubilization contribution to maize growth and nutrition. Paraburkholderia fungorum UFLA 04-21 and Pseudomonas anuradhapurensis UFPI B5-8A solubilized over 60% of Ca phosphate and produced high amounts of citric/maleic and gluconic acids in vitro, respectively. Eleven organic acids were identified in total, although not all strains produced all acids. Besides, enzymes related to the organic acids production were found in all bacterial genomes. Plants inoculated with strains UFPI B5-6 (Enterobacter bugandensis), UFPI B5-8A, and UFLA 03-10 (Paenibacillus peoriae) accumulated more biomass than the plants fertilized with BRP only. Strains UFLA 03-10 and UFPI B5-8A increased the accumulation of most macronutrients, including P. Collectively, the results show that PSBS can increase maize growth and nutrient accumulation based on Bayóvar rock phosphate fertilization.

Production of gluconic acid from the washed rice waste water using Au/MgO catalyst - A sustainable route.

The majority of the waste produced by the food and agriculture industries is abundant in proteins, carbohydrates, and fats, which can be utilized effectively in other food products or industrial products. Especially, washed rice water (WRW) contains a significant quantity of starch that has been discarded without being utilized properly. In the present investigation, we have successfully upgraded washed rice water into the industrially important intermediate, i.e., gluconic acid, using an Au/MgO catalyst in a single pot reaction. The upgrading strategy was developed in three consecutive phases using two different model reactions: (1) glucose to gluconic acid, (2) hydrolysis of starch into glucose, followed by the oxidation reaction. The results showed that almost 60% gluconic acid was achieved at room temperature with atmospheric pressure. The present investigation highlighted that hydrolysis, followed by oxidation reaction is the most promising route for upgrading WRW to gluconic acid.

Bioactivation of Konjac Glucomannan Films by Tannic Acid and Gluconolactone Addition.

Wound healing is a dynamic process that requires an optimal extracellular environment, as well as an accurate synchronization between various cell types. Over the past few years, great efforts have been devoted to developing novel approaches for treating and managing burn injuries, sepsis, and chronic or accidental skin injuries. Multifunctional smart-polymer-based dressings represent a promising approach to support natural healing and address several problems plaguing partially healed injuries, including severe inflammation, scarring, and wound infection. Naturally derived compounds offer unique advantages such as minimal toxicity, cost-effectiveness, and outstanding biocompatibility along with potential anti-inflammatory and antimicrobial activity. Herein, the main driving idea of the work was the design and development of konjac glucomannan d-glucono-1,5-lactone (KG) films bioactivated by tannic acid and d-glucono-1,5-lactone (GL) addition. Our analysis, using attenuated total reflectance-Fourier transform infrared, atomic force microscopy, and surface energy measurements demonstrated that tannic acid (TA) clearly interacted with the KG matrix, acting as its cross-linker, whereas GL was embedded within the polymer structure. All developed films maintained a moist environment, which represents a pivotal property for wound dressing. Hemocompatibility experiments showed that all tested films exhibited no hemolytic impact on human erythrocytes. Moreover, the presence of TA and GL enhanced the metabolic and energetic activity in human dermal fibroblasts, as indicated by the MTT assay, showing results exceeding 150%. Finally, all films demonstrated high antibacterial properties as they significantly reduced the multiplication rate of both Staphylococcus aureus and Escherichia coli in bacterial broth and created the inhibition zones for S. aureus in agar plates. These remarkable outcomes make the KG/TA/GL film promising candidates for wound healing applications.

"The effects of non-surgical periodontal treatment plus zinc and magnesium supplementation on oxidative stress and antioxidants enzymes in type 2 diabetes patients: a quasi-experimental study".

BACKGROUND: Periodontal Disease (PD) associated with Type 2 Diabetes Mellitus (T2DM) is a chronic condition that affects the oral cavity of people living with T2DM. The mechanisms of the interaction between type 2 Diabetes Mellitus and Periodontal diseases are complex and involve multiple pathophysiological pathways related to the systemic inflammatory process and oxidative stress. Non-surgical periodontal treatment (NSTP) is considered the standard for the management of this disease; however, patients with systemic conditions such as type 2 Diabetes Mellitus do not seem to respond adequately. For this reason, the use of complementary treatments has been suggested to support non-surgical periodontal treatment to reduce the clinical consequences of the disease and improve the systemic conditions of the patient. The use of zinc gluconate and magnesium oxide as an adjunct to non-surgical periodontal treatment and its effects on periodontal clinical features and oxidative stress in patients with Periodontal diseases -type 2 Diabetes Mellitus is poorly understood. METHODS: A quasi-experimental study was performed in patients with periodontal diseases associated with T2DM. Initially, 45 subjects who met the selection criteria were included. 19 were assigned to a control group [non-surgical periodontal treatment] and 20 to the experimental group (non-surgical periodontal treatment + 500 mg of magnesium oxide and 50 mg of zinc gluconate for oral supplementation for 30 days) and the data of 6 patients were eliminated. Sociodemographic characteristics, physiological factors, biochemical parameters, and clinical features of periodontal diseases were assessed. RESULTS: In this research a change in periodontal clinical characteristics was observed, which has been associated with disease remission. Additionally, a shift in MDA levels was presented for both groups. Furthermore, the supplementation group showed an increase in antioxidant enzymes when compared to the group that only received NSPT. CONCLUSION: The use of Zinc gluconate and magnesium oxide can serve as a complementary treatment to non-surgical periodontal treatment, that supports the remission of PD as a result of regulation-reduction of oxidative biomarkers and increase in antioxidant enzymes activity. TRIAL REGISTRATION: https://www.isrctn.com ISRCTN 14,092,381. September 13º 2023. Retrospective Registration.

Effect of Supplementation of a Butyrate-Based Formula in Individuals with Liver Steatosis and Metabolic Syndrome: A Randomized Double-Blind Placebo-Controlled Clinical Trial.

Postbiotics could exert different metabolic activities in animal models of non-alcoholic fatty liver disease (NAFLD) and in humans affected by metabolic syndrome. This is a randomized, double-blind, placebo-controlled, parallel-group clinical trial that enrolled a sample of 50 Caucasian healthy individuals with NAFLD, defined as liver steatosis, and metabolic syndrome. After a 4-week run-in, the enrolled individuals were randomized to take a food for special medical purposes with functional release, one tablet a day, containing calcium butyrate (500 mg/tablet), zinc gluconate (zinc 5 mg/tablet), and vitamin D3 (500 IU/tablet), or an identical placebo for 3 months. Liver and metabolic parameters were measured at baseline and at the end of the study. No subject experienced any adverse events during the trial. In both groups, a significant decrease in total cholesterol (TC) and triglycerides (TG) plasma levels was observed at the randomization visit vs. pre-run-in visit (p < 0.05). Regarding liver parameters, after treatment, the fatty liver index (FLI) improved significantly vs. baseline values (p < 0.05) and vs. placebo group (p < 0.05) in the active treatment group, and the hepatic steatosis index (HSI) improved significantly vs. baseline values (p < 0.05). Moreover, after active treatment, TC, TG, and gamma-glutamyl transferase (gGT) improved significantly vs. baseline values (p < 0.05), and TC and TG improved vs. placebo group (p < 0.05), as well. In the placebo group, liver parameters remained unchanged after treatment; only TG improved significantly vs. baseline values (p < 0.05). In our study, we observed that the butyrate-based formula improved FLI and plasma lipid patterns in individuals affected by liver steatosis and metabolic syndrome.

Zinc gluconate improves atopic dermatitis by modulating CXCL10 release of keratinocytes via PPARα activation.

Atopic dermatitis (AD) is a chronic inflammatory skin condition with complex causes involving immune factors. The presence of essential trace elements that support immune system function can influence the development of this condition. This study investigated how serum trace elements impact the pathogenesis of atopic dermatitis. Upon analyzing serum microelements in AD patients and control subjects, it was observed that patients with AD had notably lower zinc levels. Genomic analysis of AD skin revealed distinct gene expression patterns, specifically the increased expression of CXCL10 in the epidermis. The heightened levels of CXCL10 in AD skin lesions were found to correlate with reduced serum zinc levels. Treatment with zinc gluconate showed reduced chemotactic response and CXCL10 release, suggesting its potential to regulate CXCL10 expression of keratinocytes in AD. The mechanism behind this involved the downregulation of STAT phosphorylation through activating PPARα. In the AD-like dermatitis mouse model, zinc gluconate therapy decreased serum IgE levels, alleviated skin lesion severity, reduced skin thickness, and lowered CXCL10 expression, demonstrating its efficacy in managing AD-like skin conditions. These findings indicate that zinc gluconate can reduce inflammation in keratinocytes by activating PPARα, inhibiting STAT signaling, and decreasing CXCL10 release, thus highlighting its potential as a therapeutic target for AD.

Effects of secondary cross-linking on the physicochemical properties of sodium alginate-hydrogel and in vitro release of anthocyanins.

To enhance the physicochemical properties and extend the release duration of sodium alginate (SA) hydrogels, this study explored the impact of acidifier type and the number of cross-linking on the physicochemical characteristics and in vitro anthocyanin release from SA hydrogels, utilizing calcium carbonate as the cross-linking agent. The findings revealed that the utilization of gluconolactone (GDL) as an acidifying agent in the preparation of SA hydrogels, as opposed to hydrochloric acid, resulted in a deceleration of the hydrolysis process of calcium carbonate. This deceleration led to the strengthening of hydrogen-bonding interactions and the development of a more compact network structure within the SA hydrogels. Consequently, there was a noticeable enhancement in the hardness, relaxation time, and anthocyanin encapsulation efficiency of the gels. Additionally, the release of anthocyanins in simulated intestinal fluid was delayed. Secondary cross-linking was found to facilitate ionic interactions between SA and Ca2+, further intensifying the denseness of the network structure and enhancing the physicochemical characteristics of the SA hydrogels. Overall, SA hydrogels processed with GDL as the acidifier and subjected to secondary cross-linking exhibited improved physicochemical properties, delayed release effects, and proved to be an efficient system for the delayed release of anthocyanins.

Preparation of bovine serum albumin-arabinoxylan cold-set gels by glucono-δ-lactone and salt ions double induction.

In order to investigate the effect of glucono-δ-lactone (GDL) and different salt ions (Na+ and Ca2+) induction on the cold-set gels of bovine serum albumin (BSA)-arabinoxylan (AX), the gel properties and structure of BSA-AX cold-set gels were evaluated by analyzing the gel strength, water-holding capacity, thermal properties, and Fourier Transform Infrared (FTIR) spectra. It was shown that the best gel strength (109.15 g) was obtained when the ratio of BSA to AX was 15:1. The addition of 1 % GDL significantly improved the water-holding capacity, gel strength and thermal stability of the cold-set gels (p < 0.05), and the microstructure was smoother. Low concentrations of Na+ (3 mM) and Ca2+ (6 mM) significantly enhanced the hydrophobic interaction and hydrogen bonding between BSA and AX after acid induction, and the Na+-induced formation of a denser microstructure with a higher water-holding capacity (75.51 %). However, the excess salt ions disrupted the stable network structure of the cold-set gels and reduced their thermal stability and crystalline structure. The results of this study contribute to the understanding of the interactions between BSA and AX induced by GDL and salt ions, and provide a basis for designing hydrogels with different properties.

Enhancing Lactobacillus plantarum delivery: Impact of gluconolactone concentration on high-internal-phase emulsion gels and gastrointestinal viability.

In this study, the impact of Gluconolactone (GDL) concentration on the formation of high-internal-phase emulsion gels (HIPEGs) and the gastrointestinal digestive viability of Lactobacillus plantarum encapsulated within these HIPEGs were demonstrated. Increasing GDL concentrations led to cross-linking of particles at the oil-water interface, thereby stabilizing smaller oil droplets. The addition of GDL to HIPEs results in a significant increase in the secondary structure of SPI, specifically in ß-sheet and ß-turn formations, accompanied by a reduction in α-helix percentage. This alteration enhanced the binding effect of protein on water, leading to changes in intermolecular force. Notably, HIPEGs containing 3.0% GDL demonstrated superior encapsulation efficiency and delivery efficiency, reaching 99.0% and 84.5%, respectively. After 14 d of continuous zebrafishs feeding, the intestinal viable cells count of Lactobacillus plantarum reached 1.18 × 107 CFU/mL. This finding supports the potential use of HIPEGs as a probiotic delivery carrier, effectively enhancing the intestinal colonization rate.

Identification of Tellurium Metabolite in Broccoli Using Complementary Analyses of Inorganic and Organic Mass Spectrometry.

Tellurium (Te) is a chalcogen element like sulfur and selenium. Although it is unclear whether Te is an essential nutrient in organisms, unique Te metabolic pathways have been uncovered. We have previously reported that an unknown Te metabolite (UKTe) was observed in plants exposed to tellurate, a highly toxic Te oxyanion, by liquid chromatography-inductively coupled plasma mass spectrometer (LC-ICP-MS). In the present study, we detected UKTe in tellurate-exposed broccoli (Brassica oleracea var. italica) by LC-ICP-MS and identified it as gluconic acid-3-tellurate (GA-3Te) using electrospray ionization mass spectrometer with quadrupole-Orbitrap detector and tandem MS analysis, the high-sensitivity and high-resolution mass spectrometry for organic compounds. We also found that GA-3Te was produced from one gluconic acid and one tellurate molecule by direct complexation in an aqueous solution. GA-3Te was significantly less toxic than tellurate on plant growth. This study is the first to identify the Te metabolite GA-3Te in plants and will contribute to the investigation of tellurate detoxification pathways. Moreover, gluconic acid, a natural and biodegradable organic compound, is expected to be applicable to eco-friendly remediation strategies for tellurate contamination.

Monitoring sodium caseinate and whey protein isolate interaction with mild preheat treatment using ultrasound spectroscopy and confocal laser scanning microscopy.

Ultrasound spectroscopy and confocal laser scanning microscopy (CLSM) methods were developed to visualize the interaction between sodium caseinate (SC) and whey protein isolate (WPI) with a mild preheat treatment (57°C, 10 min) followed by adding glucono-δ-lactone (GDL). Ultrasonic velocity changes during incubation at 25°C after adding GDL for four kinds of mixtures (no-treated SC plus no-treated WPI, preheated SC plus no-treated WPI, no-treated SC plus preheated WPI and preheated SC plus preheated WPI) were monitored. The results reveal that the mild preheating treatment of the proteins affected the timing of the increase in compressibility of each system. CLSM observation with individualized dyes which have different maxima of excitation and emission wavelengths, showed the preheated SC plus no-treated WPI mixture had a slightly coarse structure and the highest correlation coefficient, suggesting the highest colocalization of the SC and WPI among the four kinds of mixed-protein systems. Furthermore, the scanning electron microscopy (SEM) observation suggests that there are some differences among the gels, namely, preheated WPI leads to the formation of developed three-dimensional gel networks with filamentous structures, whereas SC promotes the formation of cluster-like crowded networks composed of more fine aggregated particles instead of developed filamentous structures. These results demonstrated that although SC is known as a heat-stable protein, pretreated SC could lead to an increase of the collaboration with WPI in the presence of GDL. This finding anticipated the possibility creating a food material with another texture using a milk-protein mixed system.

Self-propelled enzyme-controlled IR-mesoporous silica Janus nanomotor for smart delivery.

Here, we report the preparation of a novel Janus nanoparticle with opposite Ir and mesoporous silica nanoparticles through a partial surface masking with toposelective modification method. This nanomaterial was employed to construct an enzyme-powered nanomachine with self-propulsion properties for on-command delivery. The cargo-loaded nanoparticle was provided with a pH-sensitive gate and unit control at the mesoporous face by first attaching boronic acid residues and further immobilization of glucose oxidase through reversible boronic acid esters with the carbohydrate residues of the glycoenzyme. Addition of glucose leads to the enzymatic production of H2O2 and gluconic acid, being the first compound catalytically decomposed at the Ir nanoparticle face producing O2 and causing the nanomachine propulsion. Gluconic acid leads to a pH reduction at the nanomachine microenvironment causing the disruption of the gating mechanism with the subsequent cargo release. This work demonstrates that enzyme-mediated self-propulsion improved release efficiency being this nanomotor successfully employed for the smart release of Doxorubicin in HeLa cancer cells.

Zinc for prevention and treatment of the common cold.

BACKGROUND: The common cold is an acute, self-limiting viral respiratory illness. Symptoms include nasal congestion and mucus discharge, sneezing, sore throat, cough, and general malaise. Given the frequency of colds, they are a public health burden and a significant cause of lost work productivity and school absenteeism. There are no established interventions to prevent colds or shorten their duration. However, zinc supplements are commonly recommended and taken for this purpose. OBJECTIVES: To assess the effectiveness and safety of zinc for the prevention and treatment of the common cold. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, and LILACS to 22 May 2023, and searched Web of Science Core Collection and two trials registries to 14 June 2023. We also used reference checking, citation searching, and contact with study authors to identify additional studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in children or adults that tested any form of zinc against placebo to prevent or treat the common cold or upper respiratory infection (URTI). We excluded zinc interventions in which zinc was combined with other minerals, vitamins, or herbs (e.g. a multivitamin, or mineral supplement containing zinc). DATA COLLECTION AND ANALYSIS: We used the Cochrane risk of bias tool to assess risks of bias, and GRADE to assess the certainty of the evidence. We independently extracted data. When necessary, we contacted study authors for additional information. We assessed zinc (type and route) with placebo in the prevention and treatment of the common cold. Primary outcomes included the proportion of participants developing colds (for analyses of prevention trials only), duration of cold (measured in days from start to resolution of the cold), adverse events potentially due to zinc supplements (e.g. unpleasant taste, loss of smell, vomiting, stomach cramps, and diarrhoea), and adverse events considered to be potential complications of the common cold (e.g. respiratory bacterial infections). MAIN RESULTS: We included 34 studies (15 prevention, 19 treatment) involving 8526 participants. Twenty-two studies were conducted on adults and 12 studies were conducted on children. Most trials were conducted in the USA (n = 18), followed by India, Indonesia, Iran, and Turkey (two studies each), and Australia, Burkina Faso, Colombia, Denmark, Finland, Tanzania, Thailand, and the UK (one study each). The 15 prevention studies identified the condition as either common cold (n = 8) or URTI (n = 7). However, almost all therapeutic studies (17/19) focused on the common cold. Most studies (17/34) evaluated the effectiveness of zinc administered as lozenges (3 prevention; 14 treatment) in acetate, gluconate, and orotate forms; gluconate lozenges were the most common (9/17). Zinc gluconate was given at doses between 45 and 276 mg/day for between 4.5 and 21 days. Five (5/17) lozenge studies gave acetate lozenges and two (2/17) gave both acetate and gluconate lozenges. One (1/17) lozenge study administered intranasal (gluconate) and lozenge (orotate) zinc in tandem for cold treatment. Of the 17/34 studies that did not use lozenges, 1/17 gave capsules, 3/17 administered dissolved powders, 5/17 gave tablets, 4/17 used syrups, and 4/17 used intranasal administration. Most studies were at unclear or high risk of bias in at least one domain. There may be little or no reduction in the risk of developing a cold with zinc compared to placebo (risk ratio (RR) 0.93, 95% CI 0.85 to 1.01; I2 = 20%; 9 studies, 1449 participants; low-certainty evidence). There may be little or no reduction in the mean number of colds that occur over five to 18 months of follow-up (mean difference (MD) -0.90, 95% CI -1.93 to 0.12; I2 = 96%; 2 studies, 1284 participants; low-certainty evidence). When colds occur, there is probably little or no difference in the duration of colds in days (MD -0.63, 95% CI -1.29 to 0.04; I² = 77%; 3 studies, 740 participants; moderate-certainty evidence), and there may be little or no difference in global symptom severity (standardised mean difference (SMD) 0.04, 95% CI -0.35 to 0.43; I² = 0%; 2 studies, 101 participants; low-certainty evidence). When zinc is used for cold treatment, there may be a reduction in the mean duration of the cold in days (MD -2.37, 95% CI -4.21 to -0.53; I² = 97%; 8 studies, 972 participants; low-certainty evidence), although it is uncertain whether there is a reduction in the risk of having an ongoing cold at the end of follow-up (RR 0.52, 95% CI 0.21 to 1.27; I² = 65%; 5 studies, 357 participants; very low-certainty evidence), or global symptom severity (SMD -0.03, 95% CI -0.56 to 0.50; I² = 78%; 2 studies, 261 participants; very low-certainty evidence), and there may be little or no difference in the risk of a change in global symptom severity (RR 1.02, 95% CI 0.85 to 1.23; 1 study, 114 participants; low-certainty evidence). Thirty-one studies reported non-serious adverse events (2422 participants). It is uncertain whether there is a difference in the risk of adverse events with zinc used for cold prevention (RR 1.11, 95% CI 0.84 to 1.47; I2 = 0%; 7 studies, 1517 participants; very low-certainty evidence) or an increase in the risk of serious adverse events (RR 1.67, 95% CI 0.78 to 3.57; I2 = 0%; 3 studies, 1563 participants; low-certainty evidence). There is probably an increase in the risk of non-serious adverse events when zinc is used for cold treatment (RR 1.34, 95% CI 1.15 to 1.55; I2 = 44%; 2084 participants, 16 studies; moderate-certainty evidence); no treatment study provided information on serious adverse events. No study provided clear information about adverse events considered to be potential complications of the common cold. AUTHORS' CONCLUSIONS: The findings suggest that zinc supplementation may have little or no effect on the prevention of colds but may reduce the duration of ongoing colds, with an increase in non-serious adverse events. Overall, there was wide variation in interventions (including concomitant therapy) and outcomes across the studies, as well as incomplete reporting of several domains, which should be considered when making conclusions about the efficacy of zinc for the common cold.

Higher abundance of 2-dehydro-d-gluconate in the plasma of sub-fertile or infertile Bos taurus heifers.

Infertility or subfertility impacts approximately 5% and 15% of dairy and beef heifers (Bos taurus), respectively. Heifers that do not produce a calf within an optimum window of time have a significant negative impact on the profitability and sustainability of the cattle industry. Selection of heifers based on their fertility potential remains a challenge yet to be resolved. Here, we tested the hypothesis that heifers of different fertility potential have differing metabolome signatures in their plasma. We obtained blood from Bos taurus heifers at their first artificial insemination and processed the samples to separate the plasma. The heifers were classified based on their reproductive outcome as fertile (pregnant and delivered a calf after their first artificial insemination (AI)) or sub-fertile (Angus heifers: no pregnancy after two AI and exposure to a bull; Holstein heifers: no pregnancy by the third AI). We tested the relative abundance of 140 metabolites obtained from 22 heifers (Angus fertile n = 5, Angus sub-fertile n = 7, Holstein fertile N = 5, Holstein sub-fertile N = 5). The metabolite 2-Dehydro-D-gluconate (C6H10O7) was significantly more abundant in the plasma of sub-fertile heifers in both breeds (1.4-fold, false discovery rate < 0.1). In the context that a small proportion of circulating metabolites in the plasma were quantified in this study, the results show that the metabolomic profile in the blood stream may be associated with heifer fertility potential.

During the development of heifers for cow replacement, producers must invest substantial resources in each animal for over 15 mo. While the use of resources is equivalent across heifers being developed on a farm, a substantial proportion of the animals will not produce a calf (approximately 5% and approximately 15% of dairy and beef heifers, respectively). In this study, we identified one metabolite with higher abundance in the plasma of dairy and beef heifers with low chances of producing a calf by 25 mo of age.

Dilute gluconic acid pretreatment and fermentation of wheat straw to ethanol.

Gluconic acid's potential as a wheat straw pretreatment agent was studied at different concentrations (0.125-1 M) and temperatures (160-190 °C) for 30 min, followed by enzymatic hydrolysis. 0.125 M gluconic acid, 170 °C, yielded the highest xylose output, while 0.5 M gluconic acid at 190 °C yielded the best glucose yield. A fraction of gluconic acid decomposed during pretreatment. Detoxified hemicellulose hydrolysate from 0.125 M gluconate at 170 °C for 60 min showed promise for ethanol production. The gluconate contained in the detoxified hemicellulose hydrolysate can be fermented to ethanol along with other hemicellulose sugars present by Escherichia coli SL100. The ethanol yield from gluconate and sugars was about 90.4 ± 1.8%. The pretreated solids can be effectively converted to ethanol by Saccharomyces cerevisiae D5A via simultaneous saccharification and fermentation with the cellulase and ß-glucosidase addition. The ethanol yield achieved was 92.8 ± 2.0% of the theoretical maximum. The cellulose conversion was about 70.8 ± 0.8%.

Structural effects of oxidation on sugars: glucose as a precursor of gluconolactone and glucuronolactone.

Although structural information on sugars is wide, experimental studies on the oxidation products of sugars in the gas phase, free from solvent interactions, have been rarely reported. We present an experimental work on the changes in the structure and interactions of two products of glucose oxidation (D-glucono-1,5-lactone (GlcL) and D-glucurono-6,3-lactone (GlcurL)) with respect to their precursor. Features such as intramolecular interactions, ring puckering and tautomerism were observed.

Legume milk-based yogurt mimetics structured using glucono-δ-lactone.

The potential to produce protein-structured vegan yogurts with legumes was explored to offer an alternative to conventional polysaccharide-based varieties. Glucono-δ-lactone (GDL) was employed as a slow acidifying agent and was investigated for its ability to generate cold-set, yogurt-like gels using soy and lentil milks made using minimal processing steps. Soy (5.3 % protein) and lentil (6.1 % protein) milks were successfully gelled by GDL at concentrations of 0.5 % and 1 % w/w. Soy and lentil milks experienced similar acidification profiles and demonstrated good fits with double-exponential decay models. The physical properties of these legume gels were evaluated and compared to a commercial stirred dairy yogurt. Penetration tests were carried out on intact gels, then repeated after stirring. All intact soy samples demonstrated significantly stronger gel structures compared to the commercial yogurt, and most experienced greater amounts of brittleness. Results showed that the stirring of gels caused a notable decrease in firmness and brittleness in the soy gels, making them more similar to the control. Power-law modelling of viscosity curves demonstrated that all samples experienced non-Newtonian flow behavior (n < 0.29). Susceptibility to syneresis was measured by the degree of liquid loss following centrifugation. The optimization of protein type and GDL concentration to replicate the physical properties of dairy-based yogurts can enhance their consumer acceptance and provide a more customizable and controlled approach alternative to traditional fermentation methods.