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Background: It is important to detect the predictors of prediabetes progressing to diabetes. Although polyols affect glycometabolism, little is known about the association between fasting serum polyol levels of participants with habitual diet and the risk of prediabetes progressing to type 2 diabetes. Methods: In this nested case-control study, 180 participants who developed from prediabetes to type 2 diabetes (progressors), and 180 matched controls (non-progressors) with prediabetes during a 3.5-year follow-up were enrolled. The baseline levels of serum polyols in the fasting state were quantified using time-of-flight mass spectrometry. Multivariate conditional logistic regression was performed to assess the effects of the differential polyol levels on the risk of incident diabetes from prediabetes. Results: The baseline fasting xylitol levels, but not sorbitol or erythritol levels, were higher in non-progressors than in progressors (P < 0.001). Non-progressors, in comparison with progressors, had significantly higher proportions within the third tertile of xylitol levels (71/180 non-progressors [39.4%] vs. 49/180 progressors [27.2%]). After adjusting for potential confounders, the odds ratio of risk for incident diabetes in the highest tertile of xylitol levels was 0.338 (95% confidence interval 0.182–0.628), when compared with those in the lowest tertile. In addition, the association between xylitol levels and incident diabetes was persistent in those with fasting hyperglycemia and both fasting and 2h-post-glucose-load hyperglycemia, but not in the isolated 2h-post-glucose-load hyperglycemia. Conclusions: Elevated baseline fasting serum xylitol levels are associated with a lower risk of prediabetes progressing to diabetes. This association was particularly evident in those with fasting hyperglycemia. These findings suggest that fasting serum xylitol levels may serve as an important predictor and protective factor against the development of diabetes. [ABSTRACT FROM AUTHOR]

Background/Objectives: Xylitol, a natural low-caloric bulk sweetener, is increasingly used as a sugar alternative due to its low-glycemic and low-insulinemic properties. The aim was to investigate the effect of orally administered xylitol, sucrose, and acesulfame potassium (ace-K) on energy intake during a subsequent ad libitum test meal. Methods: In this randomized, controlled, double-blind, crossover trial (ClinicalTrials.gov NCT05671965, 20 December 2022), we included 20 healthy participants with normal body weight. Over four study visits, participants consumed an oral preload containing 33.5 g xylitol, 33.5 g sucrose, or 0.1675 g ace-K dissolved in 300 mL water, or 300 mL pure water as control. Participants were provided with an ad libitum test meal 15 min after the preload consumption, and both energy intake and total energy intake (= preload + ad libitum test meal) were assessed. Blood samples were collected to quantify cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), glucose, and insulin concentrations. Results: Total energy intake was lower in response to xylitol and ace-K compared to sucrose (pTukey < 0.03), with no differences between xylitol and ace-K or water. Plasma CCK concentrations were higher in response to xylitol compared to sucrose, ace-K, and water (pHolm < 0.01), whereas GLP-1 concentrations did not differ between the preloads. Plasma glucose and insulin concentrations were lower in response to xylitol compared to sucrose (pHolm < 0.01), but xylitol led to an increase in insulin compared to ace-K and water (pHolm < 0.01). Conclusions: The consumption of oral preloads sweetened with xylitol or ace-K prior to an ad libitum test meal result in a lower total energy intake compared to a preload with sucrose. [ABSTRACT FROM AUTHOR]

Xylose conversion to xylitol instead of bioethanol is more profitable as it is a high-value chemical with several applications in food and pharma industries. The current study explores the ability of C. tropicalis for bioethanol and xylitol synthesis under anaerobic and aerobic conditions, respectively. Firstly, the effect of agitation (100, 200, 300 and 400 rpm) on glucose fermentation was evaluated. The maximum bioethanol yield and productivity of 0.49 ± 0.008 g/g and 3.62 ± 0.007 g/L/h were achieved at 200 rpm in 8 h. Subsequently, sequential fermentation was performed for bioethanol and xylitol synthesis from the glucose-xylose mixture. Bioethanol in the medium decreased xylose assimilation due to its inhibitory effect on C. tropicalis, resulting in poor xylitol yield. Bioethanol separation via distillation and xylose fed-batch fermentation with glycerol supplementation (2 g/L) was adopted to improve xylitol production. The maximum productivity of bioethanol and xylitol from glucose-xylose (59.04 ± 0.283 g/L, 50.27 ± 0.095 g/L) mixture was 3.52 ± 0.019 g/L/h and 2.19 ± 0.003 g/L/h respectively. These results were analogous to those obtained in the separate glucose and glycerol-supplemented xylose fed-batch fermentation experiments. The suggested strategy in the present work shows potential for developing biorefineries based on lignocellulose materials for the co-production of biofuels and biochemicals. [ABSTRACT FROM AUTHOR]

The development of alternatives is a priority issue for the plasticizer industry due to the reproductive toxicity and potential carcinogenicity of phthalate plasticizers. Herein we demonstrate the synthesis and characterization of multi‐branched octopus‐like plasticizers applied in poly(vinyl chloride) (PVC). The plasticizers were achieved through a straightforward one‐step esterification reaction, resulting in four polyol ester plasticizers (glyceryl tri‐n‐octanoate [GTOE], pentaerythritol tetra‐n‐octanoate [PQOE], xylitol penta‐n‐octanoate [XPOE], and mannitol hexa‐n‐octanoate [MHOE]). The multi‐branched structure enhances the interactions between plasticizers and PVC molecules leading to superior plasticizing properties, particularly mechanical properties, thermal stability, and migration resistance compared with commercial plasticizers di(2‐ethylhexyl) phthalate (DEHP), dioctyl terephthalate (DOTP), and acetyl tributyl citrate (ATBC). Concretely, the elongation at break of MHOE/PVC (825%) and PQOE/PVC (814.63%) was better than that of DEHP/PVC (670.02%), DOTP/PVC (490.62%) and ATBC/PVC (566.78%). The T5% of GTOE/PVC, PQOE/PVC, XPOE/PVC, and MHOE/PVC were 46.97, 67.24, 60.09 and 48.14°C higher than ATBC/PVC respectively. In the volatility resistance testing after 48 h, the weight loss of GTOE/PVC, PQOE/PVC, XPOE/PVC, and MHOE/PVC was 5.63%, 3.64%, 2.95%, and 8.88% respectively, which was far less than DEHP/PVC (15.58%), DOTP/PVC (11.83%) and ATBC/PVC (18.15%). Consequently, the obtained plasticizers demonstrate enhanced plasticizing efficiency, presenting promising alternatives to phthalate plasticizers and expanding the repertoire of choices within the plasticizer industry. [ABSTRACT FROM AUTHOR]

Key points: Treatment of cystic fibrosis‐related chronic rhinosinusitis should target sinonasal biofilms.NaHCO3 salts with/without xylitol have limited antibiofilm properties, whereas rhDNAse has not.Phage effectivity varies and depends on the phage and the combination with antibiotics. [ABSTRACT FROM AUTHOR]

This study presents a novel approach for producing xylitol from xylose‐rich hydrolysate derived from pistachio shells. Initially, xylose‐rich hydrolysate was obtained through microwave‐assisted high‐pressure CO2/H2O hydrolysis, achieving a maximum xylose concentration of 14.58 ± 0.11 g L−1 and yield of 62.01 ± 0.92% (w w−1). Prior to the bioconversion process, the hydrolysate was detoxified using activated charcoal to remove inhibitory compounds such as hydroxymethylfurfural (HMF) and furfural. Xylitol production from the detoxified hydrolysate was carried out biotechnologically using the yeast Candida tropicalis. A Box–Behnken design was implemented to investigate the effect of temperature, pH, and aeration rate on xylitol yield during bioconversion in bioreactor. The highest xylitol yield of 0.94 g g−1 was recorded at 72 h under optimized conditions of 34.5 °C, pH 4.5, and 1.2 vvm. Recovery and purification of xylitol from the fermentation medium was achieved using ethanol as an antisolvent. Xylitol was recovered with a yield of 68.4% from culture medium by crystallization. Based on the findings of this study, a sustainable and environmentally friendly process can be proposed for recovering and purifying xylitol from pistachio shell hydrolysate. [ABSTRACT FROM AUTHOR]

Obesity, diabetes, and tooth decay are directly related to high sugar intake. Therefore, it is important to reduce sugar consumption by replacing it with foods that provide less energy. At this juncture, xylitol provides fewer calories than sucrose and helps preventmtooth decay. Additionally, probiotics have many positive effects on host health. This study aimed to produce a tooth-friendly probiotic pudding by incorporating xylitol (25, 50, 75 and 100%) and the probiotics L. rhamnosus and S. boulardii. The effects of adding xylitol and probiotics on pH levels, syneresis, rheological properties, probiotic viability, and consumer acceptance were evaluated. The addition of xylitol resulted in a slight increase in pH, whereas the inoculation of probiotic cultures led to a notable reduction in pH values (P ≤ 0.05). The addition of xylitol reduced the syneresis levels of the puddings. The addition of xylitol resulted in an increase in the consistency values, whereas the incorporation of probiotics resulted in a reduction. Although a decline in the viability was observed for both L. rhamnosus and S. boulardii during storage, the viability of probiotics remained above the desired level (8.91 and 6 log CFU/g for both probiotics, respectively). The sensory acceptability of probiotic-free puddings was satisfactory, whereas probiotic puddings were not deemed acceptable by the panelists. Finally, this study demonstrated that xylitol could be an alternative sweetener to sucrose in the production of tooth-friendly pudding and that the pudding could be used as an alternative probiotic carrier. [ABSTRACT FROM AUTHOR]

Background: Biocatalysis offers a potentially greener alternative to chemical processes. For biocatalytic systems requiring cofactor recycling, hydrogen emerges as an attractive reducing agent. Hydrogen is attractive because all the electrons can be fully transferred to the product, and it can be efficiently produced from water using renewable electricity. In this article, resting cells of Cupriavidus necator H16 harboring a NAD-dependent hydrogenase were employed for cofactor recycling to reduce d-xylose to xylitol, a commonly used sweetener. To enable this bioconversion, d-xylose reductase from Scheffersomyces stipitis was heterologously expressed in C. necator. Results: d-xylose reductase was successfully expressed in C. necator, enabling almost complete bioconversion of 30 g/L of d-xylose into xylitol. It was found that over 90% of the energy and protons derived from hydrogen were spent for the bioconversion, demonstrating the efficiency of the system. The highest xylitol productivity reached was 0.7 g/L/h. Additionally, the same chassis efficiently produced l-arabitol and d-ribitol from l-arabinose and d-ribose, respectively. Conclusions: This study highlights the efficient utilization of renewable hydrogen as a reducing agent to power cofactor recycling. Hydrogen-oxidizing bacteria, such as C. necator, can be promising hosts for performing hydrogen-driven biocatalysis. [ABSTRACT FROM AUTHOR]

A sequential valorization process of sunflower stalks was carried out using nitric acid (0.1–2 mol dm−3) as a hydrolytic agent and fermenting the hydrolysate of higher sugar concentration in the presence of the non-conventional yeast Hansenula polymorpha. Values reached for ethanol yield (0.25 g g−1) and xylitol yield (0.14 g g−1) were higher than those achieved after pretreatment with other acids in previous studies. The effect of acid treatment with nitric, phosphoric, and sulfuric acids on the separated solid fractions was evaluated to determine its potential use as solid biofuel by FTIR and SEM determinations. A significant loss of lignin and hemicellulose was found in the solid treated with nitric acid, while a higher HHV was obtained when pretreated with phosphoric acid (19.16 MJ kg−1) and sulfuric acid (19.12 MJ kg−1). A subsequent enzymatic hydrolysis of acid-pretreated solids showed that the nitric acid pretreatment increased the availability of glucose from the cellulose fraction to a greater extent than the other two acids, by reducing the hemicellulose fraction to 0.7% and the lignin fraction to 2.5%. This study shows that pretreatment of biomass with nitric acid leads to better fermentation results to obtain biofuels such as ethanol, which could be further increased by additional enzymatic hydrolysis, while pretreatment with the other two acids generates better solid fuels. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the protective effect of xylitol on gut mucosal barrier injury in a type 2 diabetes rat model. Treatment with xylitol not only ameliorated diabetic-induced changes to small intestinal mucosa morphology and decreased diamine oxidase concentration in the serum of diabetic rats, but also modified the inflammatory infiltrates and improved the secretory IgA levels of the small intestinal epithelium. Increased expression of zo-1, occludin, mucin-2 and intestinal trefoil factor also was detected in small intestinal tissue. Intragastric administration of xylitol suppressed diabetes-induced increases of myeloperoxidase, eosinophil peroxidase, IL-6 and TNF-α. These results suggest that xylitol reduces mucosal inflammatory lesions and improves the intestinal barrier in diabetic rats by maintaining the structural integrity of the mucous layer, inhibiting the expression of inflammatory mediators and enhancing the expression of tight junction proteins associated with intestinal permeability. [ABSTRACT FROM AUTHOR]

New biobased processes and products are emerging to replace conventional ones in the search for sustainable development. Xylitol is one of the most commercially valuable products from xylan-rich lignocellulosic biomass. Xylitol has multiple applications in the pharmaceutical, food, nutraceutical, and beverage industries. Recent research focuses on obtaining xylose from low-cost lignocellulosic materials through the biological route, optimizing xylitol conversion, improving byproduct removal, and increasing crystallization speed. The biological route can be an environmentally friendly alternative due to the possibility of lower energy demand and utilizing renewable feedstocks which are key factors to reach sustainability. Several integration strategies are being evaluated and are critical to developing a commercial platform. Process integration can considerably reduce the demand for energy and reagents. Also, the value-added products produced alongside xylitol are crucial, and these products are usually energy generation and bioethanol. Further, new value-added products show promising results and are relevant to improving the economic performance of the processes. The market trends of xylitol are expected to reach close to USD 1.5 billion in 2030. In addition, the improvement needed in the conversion steps and obtained yields, producing commercial-scale xylitol through the biological route, is a promising alternative to finding a more sustainable way to produce xylitol. [ABSTRACT FROM AUTHOR]

Xylitol, as an important food additive and fine chemical, has a wide range of applications, including food, medicine, chemical, and feed. This review paper focuses on the research progress of xylitol biosynthesis, from overcoming the limitations of traditional chemical hydrogenation and xylose bioconversion, to the full biosynthesis of xylitol production using green and non-polluting glucose as substrate. In the review, the molecular strategies of wild strains to increase xylitol yield, as well as the optimization strategies and metabolic reconfiguration during xylitol biosynthesis are discussed. Subsequently, on the basis of existing studies, the paper further discusses the current status of research and future perspectives of xylitol production using glucose as a single substrate. The evolution of raw materials from xylose-based five-carbon sugars to glucose is not only cost-saving, but also safe and environmentally friendly, which brings new opportunities for the green industrial chain of xylitol. [ABSTRACT FROM AUTHOR]

Background: Many people all around the world suffer from tooth decay, a chronic infectious disease that can lead to tooth loss. Streptococcus mutans and Candida albicans are typical microorganisms involved in the caries process. Nanotechnology is one of the most exciting new developments in dentistry and can be used in the prevention of tooth. Xylitol’s antimicrobial action can be enhanced by loading it onto poly(lactic-co-glycolic acid, or PLGA) nanoparticles. Objective: The purpose of study this is to evaluate the effectiveness of PLGA/xylitol nanoparticles as an antimicrobial agent on microorganisms causing dental caries. Materials and Methods: Samples from pure isolates of the bacteria and candida were kept in nutrient agar in a fridge until needed for the investigation. The antimicrobial activity of PLGA/xylitol nanoparticles produced using solvent evaporation was evaluated. Using the agar well diffusion method, we evaluated the sensitivity of S. mutans and C. albicans to various concentrations of nanoparticles with that of a positive control [chlorhexidine (CHX) 0.2%] and a negative control (de-ionized water). The zone of inhibition is measured across the diameter of each well. A serial dilution method was used to establish the minimum inhibitory concentration of nanoparticles against S. mutans and C. albicans and then determined minimum bactericidal concentration and minimum fungicidal concentration. Results: The results demonstrated the effectiveness of PLGA/xylitol nanoparticles in preventing bacterial and fungal development. As the concentration of nanoparticles increased, the diameter of zones of inhibition against S. mutans and C. albicans grew. Mean values of inhibition zones for S. mutans at 7.5%, 10%, 15%, and 20% were greater than CHX 0.2%. Nonetheless, for Candida, the mean values of inhibitory zones are still lower than CHX 0.2% at all concentrations with a statistically significant difference (P < 0.05). Conclusion: PLGA/xylitol nanoparticles are effective in preventing the growth of the microorganisms responsible for tooth caries. Although it is effective against S. mutans, its impact on C. albicans is much lower. The synergistic action of xylitol and PLGA nanoparticles could be responsible for this antimicrobial activity. This treatment could be considered as a way of preventing dental caries.

Crop residues are valuable sources of lignocellulosic biomass that will continue to be available as long as food production for humanity continues. Maize, a cereal crop that serves as a staple food in many parts of the world and is cultivated in numerous countries, holds great importance. The surge in maize production generates substantial amounts of corncobs which can be used as feedstock for the production of xylitol, a compound with a rapidly growing market, and ethanol. In this study, hemicellulose was extracted from the corncobs to obtain xylose by subjecting them to acid hydrolysis with 1 % H2SO4. Non-conventional yeast strain Candida tropicalis Y6 isolated from rotten vegetables was tested for growth and xylose utilization potential on synthetic and acid pre-hydrolysate medium supplemented with mineral salts. Candida tropicalis Y6 exhibited high growth and sugar utilization. On synthetic medium with xylose as the sole C source it produced 6.71 g/L and 0.38 gg-1 of xylitol showing maximum conversion efficiency (53 %) at 24 h, and also produced 0.3 g/L ethanol at 48 h. When cultured on undetoxified corncob hydrolysate, C. tropicalis Y6 produced 0.41 g/L xylitol and 0.74 g/L ethanol. Its xylose conversion was severely affected in acid hydrolysates possibly due to the presence of inhibitors. This C. tropicalis Y6 strain was distinct from other reports in producing a higher level of ethanol than xylitol during fermentation of corncob acid prehydrolysate pointing towards the ratio of XR and XDH enzymes activities under studied conditions.

BackgroundCost-effective production of biofuels from lignocellulose requires the fermentation of D-xylose. Many yeast species within and closely related to the genera Spathaspora and Scheffersomyces (both of the order Serinales) natively assimilate and ferment xylose. Other species consume xylose inefficiently, leading to extracellular accumulation of xylitol. Xylitol excretion is thought to be due to the different cofactor requirements of the first two steps of xylose metabolism. Xylose reductase (XR) generally uses NADPH to reduce xylose to xylitol, while xylitol dehydrogenase (XDH) generally uses NAD+ to oxidize xylitol to xylulose, creating an imbalanced redox pathway. This imbalance is thought to be particularly consequential in hypoxic or anoxic environments.ResultsWe screened the growth of xylose-fermenting yeast species in high and moderate aeration and identified both ethanol producers and xylitol producers. Selected species were further characterized for their XR and XDH cofactor preferences by enzyme assays and gene expression patterns by RNA-Seq. Our data revealed that xylose metabolism is more redox balanced in some species, but it is strongly affected by oxygen levels. Under high aeration, most species switched from ethanol production to xylitol accumulation, despite the availability of ample oxygen to accept electrons from NADH. This switch was followed by decreases in enzyme activity and the expression of genes related to xylose metabolism, suggesting that bottlenecks in xylose fermentation are not always due to cofactor preferences. Finally, we expressed XYL genes from multiple Scheffersomyces species in a strain of Saccharomyces cerevisiae. Recombinant S. cerevisiae expressing XYL1 from Scheffersomyces xylosifermentans, which encodes an XR without a cofactor preference, showed improved anaerobic growth on xylose as the primary carbon source compared to S. cerevisiae strain expressing XYL genes from Scheffersomyces stipitis.ConclusionCollectively, our data do not support the hypothesis that xylitol accumulation occurs primarily due to differences in cofactor preferences between xylose reductase and xylitol dehydrogenase; instead, gene expression plays a major role in response to oxygen levels. We have also identified the yeast Sc. xylosifermentans as a potential source for genes that can be engineered into S. cerevisiae to improve xylose fermentation and biofuel production.

Oil palm empty fruit bunch (OPEFB) is one of the wastes that has high hemicellulose composition and potentially processed into xylitol via biotransformation route. This study explores the effectiveness of ultrafiltration (UF) and nanofiltration (NF) in purifying and concentrating xylitol from OPEFB hydrolysate-fermentation broth. Various UF membranes, including UF1 (MWCO 150 kDa), UF2-Psf (MWCO 20 kDa), and UF2-PVDF (MWCO 50 kDa), were used, along with NF (MWCO 150 Da). Pre-treating the broth before UF was crucial to remove foulants such as microorganisms and macromolecules. While microfiltration (MF) achieved 100% microorganism rejection, its flux declined rapidly, necessitating feed centrifugation before MF. The choice of UF membrane MWCO significantly influenced xylitol retention, with UF2-PSf leading to substantial xylitol loss and UF2-PVDF showed promising results. NF has shown its applicability in concentrating xylitol in the UF permeate as much as 4 times higher, while permeating 90% of the acetic adic in the solution. [ABSTRACT FROM AUTHOR]

This study aimed to develop an eco-friendly and efficient low-sugar marination technology for making sugar-shelled marinated eggs. Low-sugar sugar-shelled marinated eggs were prepared by partially replacing sucrose with xylitol under the assistance of high intensity ultrasound (HIU) treatments at different power levels (100, 200 and 300 W). The effects of HIU treatments on the gel properties, structural changes and sensory attributes of sugar-shelled marinated eggs were systematically investigated. The results showed that HIU treatment at 100 W significantly improved the cohesiveness and water-holding capacity of proteins in low-sugar marinated eggs, and significantly increased its hydrophobicity and digestibility, while HIU treatment at 200 W increased the zeta potential and β-fold content of the yolk, disrupted the cross-linking structure of protein molecules, and facilitated the formation of loose and porous structure. Moreover, the contents of aromatic substances and nitrogen oxides in marinated eggs was increased under 200 W HIU treatment, and the flavor quality was enhanced. This study provides a theoretical basis for the innovative development of marinated egg products and the application of HIU technology in food processing.

Abstract Background Currently, the synthesis of compounds based on microbial cell factories is rapidly advancing, yet it encounters several challenges. During the production process, engineered strains frequently encounter disturbances in the cultivation environment or the impact of their metabolites, such as high temperature, acid-base imbalances, hypertonicity, organic solvents, toxic byproducts, and mechanical damage. These stress factors can constrain the efficiency of microbial fermentation, resulting in slow cell growth, decreased production, significantly increased energy consumption, and other issues that severely limit the application of microbial cell factories. Results This study demonstrated that sterol engineering in Kluyveromyces marxianus, achieved by overexpressing or deleting the coding genes for the last five steps of ergosterol synthase (Erg2-Erg6), altered the composition and ratio of sterols in its cell membrane, and affected its multiple tolerance. The results suggest that the knockout of the Erg5 can enhance the thermotolerance of K. marxianus, while the overexpression of the Erg4 can improve its acid tolerance. Additionally, engineering strain overexpressed Erg6 improved its tolerance to elevated temperature, hypertonic, and acid. YZB453, obtained by overexpressing Erg6 in an engineering strain with high efficiency in synthesizing xylitol, produced 101.22 g/L xylitol at 45oC and 75.11 g/L xylitol at 46oC. Using corncob hydrolysate for simultaneous saccharification and fermentation (SSF) at 46oC that xylose released from corncob hydrolysate by saccharification with hemicellulase, YZB453 can produce 45.98 g/L of xylitol, saving 53.72% of the cost of hemicellulase compared to 42oC. Conclusions This study elucidates the mechanism by which K. marxianus acquires resistance to various antifungal drugs, high temperatures, high osmolarity, acidity, and other stressors, through alterations in the composition and ratio of membrane sterols. By employing sterol engineering, the fermentation temperature of this unconventional thermotolerant K. marxianus was further elevated, ultimately providing an efficient platform for synthesizing high-value-added xylitol from biomass via the SSF process at temperatures exceeding 45 °C.

Objective: This study aimed to investigate the effects of two types of gum, containing xylitol or casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), on saliva properties.Methods: In this single-blind clinical trial, 60 dental students were randomly divided into three groups (n=20). Each group was instructed to chew one of the following substances: paraffin (control), xylitol gum, or CPP-ACP gum. Saliva samples were collected before and five minutes after chewing. Saliva volume was measured using a pipette, and saliva pH was evaluated with a digital pH meter. The calcium concentration was determined using the photometric method, while phosphorus concentration was measured via spectrophotometry. Statistical analysis was performed using the chi-square test, ANOVA, Tukey HSD post hoc test, and paired t-test (α = 0.05).Results: Chewing all three substances significantly increased saliva volume and pH while reducing phosphorus ion concentration (P < 0.05). The calcium ion level increased significantly after five minutes of chewing the CPP-ACP gum (P = 0.002). After the intervention, between-group comparisons revealed no significant difference in saliva volume and pH (P > 0.05). However, the calcium level in the CPP-ACP group was significantly higher than the control group (P = 0.01). Additionally, the phosphorus ion level was significantly lower in the xylitol gum group than in the control and the CPP-ACP groups (P < 0.05).Conclusions: Chewing CPP-ACP gum may promote oral health more effectively than xylitol gum by increasing salivary calcium levels and less affecting phosphorus levels.

Dental plaque provides a proper environment for the growth and activity of bacteria responsible for periodontal diseases and caries. As a result, it should be removed by individuals to prevent periodontal diseases and caries. There are different mechanical and chemical plaque control methods. In one study is shown that dental plaque removal efficacy of dentifrice containing Ethylenediaminetetraaceticacid(EDTA)/Methylsulfonylmethane(MSM) was nearly five times that of commercially available fluoride toothpaste. In another study, authors found that xylitol-containing chewing gums caused a marked reduction in the count of Streptococcus Mutans compared to conventional ones. This difference was highly prominent in individuals with poor oral hygiene. In this study we assessed the synergic effects of Xylitol, EDTA and MSM in a chewing gum in comparison with chlorhexidine mouthwash. This study was a crossover, randomized clinical trial. Twenty-four patients were divided in two groups randomly. At the baseline scaling and root planing was done for each patient. Group1 used chlorhexidine mouthwash twice a day. Group2 used novel chewing gum for 15 min twice a day. After 14 days, for every patient O'leary plaque index, gingival index and sulcus bleeding index were reevaluated and recorded. Professional brushing was done for patients. 14 days were considered as wash-out period. After that, method of plaque control of groups was changed. After 14 days, all patients were reevaluated and recorded and were compared with previous data. Samples in 2 groups had no significant difference in age and sex. Paired sample t test revealed that there were significant differences between first and second period for O'leary plaque index, gingival index and sulcus bleeding index in Group1 (P < 0.05). But in Group2 there were no differences between first and second period for all indexes. Also independent sample t test showed that there were no significant differences between baseline, after first treatment and after second one for all indexes in both groups (P > 0.05). According to regression model results, type of treatment had no effect on mean of all indexes. According to our findings which showed the similar efficiency of novel chewing gum and chlorhexidine mouthwash in improving and reducing plaque and gingival indexes, we can conclude that novel chewing gum can be introduced as an effective, cheap and accessible tool for dental plaque control. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low- and no-calorie sweeteners (LNCSs) impart sweetness while providing little or no energy. Their safety and weight management efficacy remain unsettled science that leaves open questions among consumers, researchers, clinicians, and policy makers. The objective of this narrative review is to provide a critical consideration of the safety and efficacy of weight management evidence for LNCSs that have been reviewed/approved by the US Food and Drug Administration and have the highest frequency of use: acesulfame potassium, allulose, aspartame, erythritol, monk fruit, saccharin, stevia, sucralose, and xylitol. Safety assessments by the authoritative bodies for the World Health Organization, European Union, and United States were reviewed. Additionally, emerging topics of interest regarding the safety of these sweeteners commonly cited in the recent literature or highlighted in the media are discussed. Collectively, authoritative assessments and the primary literature support the safety of the sweeteners reviewed herein, with high concordance of safety substantiation across authoritative bodies. Weight management efficacy, measured by various adiposity indices in epidemiological studies, ranges from no effect to a slight positive association. Clinical trials with various mixtures of LNCSs more consistently indicate LNCS use is associated with lower adiposity indices. The latter are ascribed greater evidentiary weight, and recent application of statistical methods to better correct for potential biases in cohort studies reveals they are more consistent with the clinical trial findings. Studies that investigated individual sweeteners were limited but suggestive of differing effects or lack of sufficient data to support any formal conclusions on their efficacy for weight management. Taken together, and consistent with the current 2020-2025 Dietary Guidelines for Americans, the evidence indicates LNCS use is safe and may aid weight management. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Converting agricultural biomass wastes into bio-chemicals can significantly decrease greenhouse gas emissions and foster global initiatives towards mitigating climate change. This study examined the co-production of xylitol and ethanol from xylose and glucose-rich hydrolysates of corn cob (CC), sugarcane bagasse (SCB), and rice straw (RS) without prior detoxification, using C. magnoliae (C. mag), C. tropicalis (C. trop), and C. guilliermondii (C. guil). A score ranking system based on weighted yields and productivity assessed the best raw material and yeast strain combination. The study revealed that C. mag cultivated on RS hemicellulosic and CC cellulosic media exhibited statistically significant (p ≤ 0.05) superiority in xylitol (272 ± 5) and ethanol 273 ± 3, production. The single-phase emulsion system using frozen-thawed whole cells of CC—C. mag, CC—C. trop, and RS—C. guil was utilized for phenylacetylcarbinol (PAC) biotransformation. Although similar PAC concentration within 14.4–14.7 mM was obtained, the statistically significant higher (p ≤ 0.05) volumetric pyruvate decarboxylase (PDC) activity from C. mag at 360 min was observed by 28.3 ± 1.51%. Consequently, further utilization of CC—C. mag in a two-phase emulsion system (Pi buffer: vegetable oil (Vg. oil) and Pi buffer: deep eutectic solvents (DES)) revealed that Pi buffer: DES medium preserved volumetric PDC activity (54.0 ± 1.2%) statistically significant higher (p ≤ 0.05) than the Pi buffer: Vg. oil system (34.3 ± 1.3%), with no statistically significant difference (p > 0.05) in [PAC]. These findings outlined the sustainable pioneering approach for the co-production of chemicals and reusing the residual yeast cells for PAC biotransformation in the Pi buffer: DES system. [ABSTRACT FROM AUTHOR]

Introduction: Streptococcus mutans adherence to the tooth surface and subsequent biofilm development is modulated by the carbohydrate source, but the corresponding effect on bacterial proteome has not been previously studied. This study aimed to assess the effect of different carbohydrates on S. mutans viability and bacterial proteome at 2 time points, early attachment (8 h) and biofilm maturation (24 h). Methods: Hydroxyapatite (HAp) discs coated with parotid saliva proteins were inoculated with S. mutans UA159 in tryptone soy broth without dextrose supplemented with one of the following carbohydrates (n = 12/treatment/time point): 1% sucrose; 0.525% glucose + 0.525% fructose; 10% xylitol; 10% xylitol + 1% sucrose; or culture medium without supplementation as negative control. Once inoculated, HAp discs were incubated for 8 h or 24 h at 37°C and 10% CO2. After each incubation period, adhered bacteria were quantified using the plate-counting method for 6 HAp discs/group, and the remaining 6 HAp discs/group were used to extract bacterial cell wall proteins. Extracted proteins were analyzed using liquid chromatography coupled with mass spectrometry and then classified by their biological process. The study was conducted in three independent assays, and the number of bacteria adhered to the HAp discs was determined at each time point and analyzed by two-way ANOVA followed by Bonferroni test (α = 5%). Results: The results suggest that xylitol significantly repressed bacterial adherence and metabolism at 8 h and 24 h; however, bacterial adherence and metabolism were significantly enhanced when xylitol was combined with sucrose, showing no negative effect on S. mutans at both time points. Bacterial proteome was modulated by the carbohydrate source. Conclusion: The cariogenicity of S. mutans biofilms may be reduced by the alternative sweetener xylitol; however, the combination with fermentable sugars may inhibit such a beneficial effect. [ABSTRACT FROM AUTHOR]

Background: Currently, the synthesis of compounds based on microbial cell factories is rapidly advancing, yet it encounters several challenges. During the production process, engineered strains frequently encounter disturbances in the cultivation environment or the impact of their metabolites, such as high temperature, acid-base imbalances, hypertonicity, organic solvents, toxic byproducts, and mechanical damage. These stress factors can constrain the efficiency of microbial fermentation, resulting in slow cell growth, decreased production, significantly increased energy consumption, and other issues that severely limit the application of microbial cell factories. Results: This study demonstrated that sterol engineering in Kluyveromyces marxianus, achieved by overexpressing or deleting the coding genes for the last five steps of ergosterol synthase (Erg2-Erg6), altered the composition and ratio of sterols in its cell membrane, and affected its multiple tolerance. The results suggest that the knockout of the Erg5 can enhance the thermotolerance of K. marxianus, while the overexpression of the Erg4 can improve its acid tolerance. Additionally, engineering strain overexpressed Erg6 improved its tolerance to elevated temperature, hypertonic, and acid. YZB453, obtained by overexpressing Erg6 in an engineering strain with high efficiency in synthesizing xylitol, produced 101.22 g/L xylitol at 45oC and 75.11 g/L xylitol at 46oC. Using corncob hydrolysate for simultaneous saccharification and fermentation (SSF) at 46oC that xylose released from corncob hydrolysate by saccharification with hemicellulase, YZB453 can produce 45.98 g/L of xylitol, saving 53.72% of the cost of hemicellulase compared to 42oC. Conclusions: This study elucidates the mechanism by which K. marxianus acquires resistance to various antifungal drugs, high temperatures, high osmolarity, acidity, and other stressors, through alterations in the composition and ratio of membrane sterols. By employing sterol engineering, the fermentation temperature of this unconventional thermotolerant K. marxianus was further elevated, ultimately providing an efficient platform for synthesizing high-value-added xylitol from biomass via the SSF process at temperatures exceeding 45 °C. [ABSTRACT FROM AUTHOR]

d-Xylitol is a naturally occurring sugar alcohol present in diverse plants that is used as an alternative sweetener based on a sweetness similar to sucrose and several health benefits compared to conventional sugar. However, current industrial methods for d-xylitol production are based on chemical hydrogenation of d-xylose, which is energy-intensive and environmentally harmful. However, efficient conversion of l-arabinose as an additional highly abundant pentose in lignocellulosic materials holds great potential to broaden the range of applicable feedstocks. Both pentoses d-xylose and l-arabinose are converted to d-xylitol as a common metabolic intermediate in the native fungal pentose catabolism. To engineer a strain capable of accumulating d-xylitol from arabinan-rich agricultural residues, pentose catabolism was stopped in the ascomycete filamentous fungus Aspergillus niger at the stage of d-xylitol by knocking out three genes encoding enzymes involved in d-xylitol degradation (ΔxdhA, ΔsdhA, ΔxkiA). Additionally, to facilitate its secretion into the medium, an aquaglyceroporin from Saccharomyces cerevisiae was tested. In S. cerevisiae, Fps1 is known to passively transport glycerol and is regulated to convey osmotic stress tolerance but also exhibits the ability to transport other polyols such as d-xylitol. Thus, a constitutively open version of this transporter was introduced into A. niger, controlled by multiple promoters with varying expression strengths. The strain expressing the transporter under control of the PtvdA promoter in the background of the pentose catabolism-deficient triple knock-out yielded the most favorable outcome, producing up to 45% d-xylitol from l-arabinose in culture supernatants, while displaying minimal side effects during osmotic stress. Due to its additional ability to extract d-xylose and l-arabinose from lignocellulosic material via the production of highly active pectinases and hemicellulases, A. niger emerges as an ideal candidate cell factory for d-xylitol production from lignocellulosic biomasses rich in both pentoses. In summary, we are showing for the first time an efficient biosynthesis of d-xylitol from l-arabinose utilizing a filamentous ascomycete fungus. This broadens the potential resources to include also arabinan-rich agricultural waste streams like sugar beet pulp and could thus help to make alternative sweetener production more environmentally friendly and cost-effective. [ABSTRACT FROM AUTHOR]

Introduction: Butterfly pea (Clitoria ternatea) flowers are rich in nutrients and anthocyanin, which contributes to their antioxidant properties. The utilisation of the natural blue colour of butterfly pea flowers as a substitute for synthetic colouring agents could add functional value to food products. Accordingly, this study was conducted to develop an instant blue drink from butterfly pea flowers and analyse its physicochemical properties and storage stability on the antioxidant activity. Materials and methods: The obtained extract was formulated with 12.3% xylitol and 0.03% citric acid and freeze-dried. The physicochemical including bulk density, colour, pH, nutritional analysis, mineral content and antioxidant properties of the instant blue drink were analysed. The antioxidant activity of the instant blue drink was evaluated after 30 days at four storage conditions as below: condition A = stored at 4°C with presence of light, condition B = stored at 4°C with absence of light, condition C = stored at 23°C with presence of light and condition D = stored at 23°C with absence of light. Results: The colour of the instant blue drink was mainly affected by the dilution of the extract and the addition of citric acid, which also subsequently changed the pH of the drink. Compared with fresh butterfly pea flowers, the instant blue drink showed value more than 50% in L*, showing the sample lighter in color. The instant blue drink had positive a* value and negative b* corresponds with blue. The moisture, ash, fat, protein and crude fibre percentage compositions of the instant blue drink were 1.46%, 0.13%, 1.94%, 0.89% and 0.43%, respectively and has the least amount of minerals. The antioxidant activity of the instant blue drink was significantly reduced (p< 0.05) by high temperature and present of light during storage. Conclusion: The optimal storage condition of instant blue drink is at 4 °C with the absence of light. Hence, instant blue drink from butterfly pea flowers (Clitoria ternatea) were successfully developed by using freeze-drying method. [ABSTRACT FROM AUTHOR]

This research aims to correlate poly(xylitol sebacate) (PXS) nanoparticle formation via nanoprecipitation in the presence of Pluronic® F-127 to changes in polymer reaction times. PXS is successfully synthesized using xylitol and sebacic acid via melt polymerization (MP) at 10, 15 and 20 h. 1H-NMR and 13C-NMR confirmed the successful formation of PXS branched structures by the conversion of hydroxyl groups to acyl groups and ester bond formation in two different environments. The degree of branching and gel fraction increased with longer reaction time, which resulted in the crosslinking of PXS-MP-20H, deeming it insoluble for nanoparticle formation. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) confirmed the thermal stability up to ~ 200 °C and an amorphous nature with subambient glass transition temperatures (Tg). Among all polyesters, PXS-MP-15H showed best and only nanoparticle formation with average diameter size ranging from 112 to 132 nm for curcumin-loaded and unloaded respectively confirmed using dynamic light scattering (DLS). PXS-MP-15H nanoparticles had a curcumin encapsulation efficiency of 23.9%. This study shows the potential of highly branched polyesters such as PXS for use as drug carriers for targeted delivery. [ABSTRACT FROM AUTHOR]

Background: The low solubility of Tobacco Etch Virus (TEV) protease, a functional enzyme that cleaves protein tags without significant modification in its sequence, is one of the most important limitations of this enzyme. In this study, the aim was to increase the solubility of TEV by changing the expression conditions and designing lysis buffer with various solubilizing agents to improve its solubility. Methods: Escherichia coli (E. coli) BL21 (DE3) and E. coli origami harboring wild type TEV-pKR793 and mutant N23F TEV-pKR793 plasmids were used for the expression. Response surface methodology was used to determine the best culture conditions (IPTG concentration, incubation time and incubation temperature) of soluble expression. Furthermore, eight different solubilizing agents were added separately to the lysis buffer to check their effect on the protein solubility. Results: The production of soluble N23F in E. coli BL21 (DE3) was two-folds more than the wild type and the inclusion body formation in the mentioned form was diminished as about 25% in comparison to the wild type. Finally, betaine had the most effects for enhancing the soluble expression of N23F in both host cells. For the wild type, sodium selenite, xylitol, and glycine showed the most effects on soluble production. Conclusion: The solubility of the mutant form of TEV protease increased in E. coli BL21 (DE3) compared to its wild form. Also, using additives such as betaine to the lysis buffer, increased the solubility of N23F in E. coli BL21 (DE3) and origami strains. [ABSTRACT FROM AUTHOR]

Copyright of Medical Journal of Babylon is the property of Wolters Kluwer India Pvt Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Development of insecticide resistance in the major malaria vectors has necessitated the development of novel vector control tools. One such strategy involves the use of toxic sugar baits that targets the sugar‐feeding behaviour of mosquito vectors. In this study, we investigated the potential of polyols, as a toxic food (sugar) source in toxic sugar baits against the malaria vector Anopheles stephensi Liston. We examined the acute toxicity of six polyols, namely, erythritol, glycerol, mannitol, propylene glycol (PG), sorbitol, and xylitol on adult female An. stephensi mosquitoes at two different concentrations – 2% and 10%. We also studied changes in fecundity, egg hatchability and mid‐gut peroxide levels induced by polyol exposure. RESULTS: Among the six polyol compounds tested, PG was most toxic and lethal followed by glycerol and erythritol (P < 0.001) compared to the control (sucrose). PG induced acute mortality at different tested concentrations. In the erythritol‐ and glycerol‐fed groups, a dose‐dependent effect on mortality was observed. Glycerol evidently reduced fecundity and egg‐hatchability in gonotrophic cycles G1 and G2. Sucrose was the preferred food source (48%), followed by erythritol (18%), PG (10%) and glycerol (8%). Ingestion of polyols increased peroxide levels in mosquito guts, which persisted for extended durations ultimately resulting in rapid mortality (P < 0.05). CONCLUSION: The present study highlights the usefulness of sugar polyols for the development of toxic sugar baits with minimal yet effective ingredients. Further research could be focused on field experiments and on the exploration of synergistic effects of different polyols for optimization of field applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Palm kernel oil (PKO) is a non-edible oil which is enriched with saturated fatty acids that can be used as a raw material for many industrial applications. Indian PKO (IPKO) was chosen in this study which has been explored sporadically in industries. IPKO was characterized and utilized for the synthesis of fatty acid alkyl esters through transesterification (solvolysis) using methanol and ethanol solvents coupled with alkali catalysts such as sodium hydroxide (NaOH) and potassium hydroxide (KOH). Upon comparison, methanol and NaOH resulted in the maximum biodiesel (esters) yield of 67.77% as compared to ethanol-based solvolysis. Compositional analysis of fatty acid methyl esters (FAMEs) through GC–MS elucidated the presence of long chain (C12:0 to C18:1) esters, which can be utilized as biodiesel. Therefore, IPKO FAME has been tested as diesel blend in engines without any modification, where, B5 (5% v/v) blend showed at-par fuel characteristics and engine efficiency as compared to non-blended diesel with minimal emissions. To induct a waste circular reprocessing startegy, crude glycerol resulted from transesterification of IPKO was supplemented to Candida tropicalis NCIM3118 for xylitol (a sweetener) synthesis. The results indicated that upon supplemention of IPKO crude glycerol as co-substrate, enhancement in xylitol production of about 0.93 gxylitol/gtotal organic carbon as compared to only xylose as 'C' source (0.81 gxylitol/gtotal organic carbon) was observed with efficiency improvement in overall growth kinetic behavior. This study demonstrates the circular economy approach in which that the IPKO can be utilized for biodiesel production, while, the by-product (crude glycerol) generated could be deployed for xylitol production. [ABSTRACT FROM AUTHOR]

In this study, xylitol, a common sweetener and sucrose substitute in low-calorie foods, was quantified by high-performance liquid chromatography (HPLC). During the establishment of the analytical method, three representative detection approaches, ultraviolet detector (UVD), evaporative light scattering detector, and refractive index detector, were compared and applied to determine the xylitol content in various foods distributed in Korea. The results were compared for method validation, measurement uncertainty, and applicability. As a result, HPLC-UVD showed the lowest limit of detection (0.01 mg/L) and limit of quantification (0.04 mg/L) among the three methods. It showed a low range of relative expanded uncertainty (1.12–3.98%) and could quantify xylitol in the wide range of the samples, even trace amounts of xylitol. Therefore, a total of 160 food items, including chewing gum, candy, beverage, tea, other processed products, and beverage base, were applied with three replicates by the proposed HPLC-UVD method. [ABSTRACT FROM AUTHOR]

Co-generation of high value-added products like xylitol, which has various applications in the pharmaceutical and food industries, can support the economics of bioethanol in an integrated biorefinery. This work proposes a sequential fermentation approach using Z. mobilis and C. tropicalis to produce bioethanol and xylitol from mixed sugars (glucose and xylose) in a single bioreactor. The sequential fermentation without ethanol separation resulted in lower xylose uptake due to the repressive effect of ethanol on C. tropicalis. Thus, an in situ distillation technique was employed for bioethanol recovery prior to xylose fermentation by C. tropicalis. From the mixture of glucose and xylose (60 and 50 g/L), the ethanol and xylitol concentration of 29.94 ± 0.208 g/L and 35.15 ± 0.472 g/L with fermentation efficiency of 97.14 ± 1.054% and 78.55 ± 0.304% respectively was achieved. Fed-batch configuration was further incorporated into this strategy to enhance the xylitol production, which resulted in the high xylitol concentration, productivity, and yield of 86.76 ± 0.416 g/L, 2.07 ± 0.010 g/L/h, and 0.87 ± 0.004 g/g respectively. The bioethanol and xylitol titer, productivity, and yield obtained from sequential fermentation of mixed sugars were similar to the distinct glucose and xylose fermentation in a bioreactor. The proposed technique can be a promising approach for developing lignocellulosic material-based biorefineries to produce bioethanol and xylitol economically and sustainably. [ABSTRACT FROM AUTHOR]

Copyright of Cumhuriyet Dental Journal is the property of Cumhuriyet University, Faculty of Dentistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Magnaporthe oryzae causes rice blast disease, which threatens global rice production. The interaction between M. oryzae and rice is regarded as a classic model for studying the relationship between the pathogen and the host. In this study, we found a gene, MoHG1, regulating fungal development and virulence in M. oryzae. The ∆Mohg1 mutants showed more sensitivity to cell wall integrity stressors and their cell wall is more easily degraded by enzymes. Moreover, a decreased content of chitin but higher contents of arabinose, sorbitol, lactose, rhamnose, and xylitol were found in the ∆Mohg1 mutant. Combined with transcriptomic results, many genes in MAPK and sugar metabolism pathways are significantly regulated in the ∆Mohg1 mutant. A hexokinase gene, MGG_00623 was downregulated in ∆Mohg1, according to transcriptome results. We overexpressed MGG_00623 in a ∆Mohg1 mutant. The results showed that fungal growth and chitin contents in MGG_00623-overexpressing strains were restored significantly compared to the ∆Mohg1 mutant. Furthermore, MoHG1 could interact with MGG_00623 directly through the yeast two-hybrid and BiFC. Overall, these results suggest that MoHG1 coordinating with hexokinase regulates fungal development and virulence by affecting chitin contents and cell wall integrity in M. oryzae, which provides a reference for studying the functions of MoHG1-like genes. [ABSTRACT FROM AUTHOR]

The circular economy is anticipated to bring a disruptive transformation in manufacturing technologies. Robust and industrial scalable microbial strains that can simultaneously assimilate and valorize multiple carbon substrates are highly desirable, as waste bioresources contain substantial amounts of renewable and fermentable carbon, which is diverse. Lignocellulosic biomass (LCB) is identified as an inexhaustible and alternative resource to reduce global dependence on oil. Glucose, xylose, and arabinose are the major monomeric sugars in LCB. However, primary research has focused on the use of glucose. On the other hand, the valorization of pentose sugars, xylose, and arabinose, has been mainly overlooked, despite possible assimilation by vast microbial communities. The present review highlights the research efforts that have explicitly proven the suitability of arabinose as the starting feedstock for producing various chemical building blocks via biological routes. It begins by analyzing the availability of various arabinose-rich biorenewable sources that can serve as potential feedstocks for biorefineries. The subsequent section outlines the current understanding of arabinose metabolism, biochemical routes prevalent in prokaryotic and eukaryotic systems, and possible products that can be derived from this sugar. Further, currently, exemplar products from arabinose, including arabitol, 2,3-butanediol, 1,2,3-butanetriol, ethanol, lactic acid, and xylitol are discussed, which have been produced by native and non-native microbial strains using metabolic engineering and genome editing tools. The final section deals with the challenges and obstacles associated with arabinose-based production, followed by concluding remarks and prospects. [ABSTRACT FROM AUTHOR]

Background: Xylitol, a five-carbon polyalcohol, is used in the food and pharmaceutical industries and as a building block in the synthesis of high-value chemicals. It can be sustainably produced from renewable sources through xylose assimilating microbe fermentation. Results: We screened microbial strains for xylitol production and identified Wickerhamomyces anomalus Z1 as a key xylitol producer. Utilizing lignocellulosic biomass hydrolysates for xylitol production poses challenges due to microbial sensitivity to inhibitors from biomass pre-treatment. In this study, an adaptive laboratory evolution (ALE) of W. anomalus Z1 was performed by culturing the yeast in a mineral medium supplemented with gradual increases of sugarcane bagasse hemicellulosic hydrolysate (SCHH) obtained by intensified steam explosion pretreatment. The performance of the adapted yeast, named Wickerhamomyces anomalus ALE, was assessed in comparison to the wild-type strain regarding its capacity to produce xylitol using SCHH. The evolved yeast reached a xylitol yield of 0.11 g xylitol/g xylose whereas the wild-type strain could not produce xylitol. Removing acetic acid from SCHH enhanced W. [ABSTRACT FROM AUTHOR]

Agro-industrial waste is increasingly utilized in biotechnological processes to convert lignocellulosic materials into high-value products, such as xylitol. This polyol can be produced using biotechnological methods that mitigate environmental impacts, but it entails high purification costs. The article proposes a comparative study between two sequential strategies for purifying biotechnological xylitol. The first strategy involves membrane filtration followed by column adsorption. While the second strategy only covers column adsorption with twice the adsorbent bed. Additionally, the study includes a cytotoxicity evaluation of various purified xylitol fractions. Column adsorption was conducted at 70 °C with a flow rate of 1.2 mL min-1 using activated carbon as the adsorbent. It proved to be efficient in separating colored compounds, proteins, and ethanol, with retention coefficients of 99.23 %, 84.0 %, and 96.71 %, respectively. The purification factor of xylitol/ethanol was 14.84. Nanofiltration was performed using a poly (piperazine amide) membrane at 40 °C and 30 bar, resulting in a protein retention of 43.55 % and a xylitol purity of 27.73 %. Finally, purified xylitol fractions underwent cytotoxicity analysis using the MIT assay, conducted in intestinal epithelial cells (Caco-2). One of the analyzed fractions did not induce toxicity, demonstrating that activated carbon column adsorption was the most effective strategy for purifying biotechnologically produced xylitol. These findings contribute to enhancing the viability of biotechnological xylitol production from sugarcane bagasse hemicellulosic hydrolysate. [ABSTRACT FROM AUTHOR]