Recent advances in biological production of sugar alcohols

Anticandidal applications of selenium nanoparticles biosynthesized with Limosilactobacillus fermentum (OR553490)

Candida albicans is one of the most dangerous pathogenic fungi in the world, according to the classification of the World Health Organization, due to the continued development of its resistance to currently available anticandidal agents. To overcome this problem, the current work provided a simple, one-step, cost-effective, and safe technique for the biosynthesis of new functionalized anticandidal selenium nanoparticles (Se NPs) against C. albicans ATCC10231 using the cell-free supernatant of Limosilactobacillus fermentum (OR553490) strain. The bacterial strain was isolated from yogurt samples available in supermarkets, in Damietta, Egypt. The mixing ratio of 1:9 v/v% between cell-free bacterial metabolites and sodium selenite (5 mM) for 72 h at 37 °C were the optimum conditions for Se NPs biosynthesis. Ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), Zeta analyses, and elemental analysis system (EDS) were used to evaluate the optimized Se NPs. The Se NPs absorption peak appeared at 254 nm. Physicochemical analysis of Se NPs revealed the crystalline-shaped and well-dispersed formation of NPs with an average particle size of 17-30 nm. Se NPs have - 11.8 mV, as seen by the zeta potential graph. FT-IR spectrum displayed bands of symmetric and asymmetric amines at 3279.36 cm-1 and 2928.38 cm-1, aromatic and aliphatic (C-N) at 1393.32 cm-1 and 1237.11.37 cm-1 confirming the presence of proteins as stabilizing and capping agents. Se NPs acted as a superior inhibitor of C. albicans with an inhibition zone of 26 ± 0.03 mm and MIC value of 15 µg/mL compared to one of the traditional anticandidal agent, miconazole, which revealed 18 ± 0.14 mm and 75 µg/mL. The cytotoxicity test shows that Se NPs have a low toxic effect on the normal keratinocyte (IC50 ≈ 41.5 μg/mL). The results indicate that this green synthesis of Se NPs may have a promising potential to provide a new strategy for drug therapy.

Sustainable biorefinery approach by utilizing xylose fraction of lignocellulosic biomass

Lignocellulosic biomass (LCB) has been a lucrative feedstock for developing biochemical products due to its rich organic content, low carbon footprint and abundant accessibility. The recalcitrant nature of this feedstock is a foremost bottleneck. It needs suitable pretreatment techniques to achieve a high yield of sugar fractions such as glucose and xylose with low inhibitory components. Cellulosic sugars are commonly used for the bio-manufacturing process, and the xylose sugar, which is predominant in the hemicellulosic fraction, is rejected as most cell factories lack the five‑carbon metabolic pathways. In the present review, more emphasis was placed on the efficient pretreatment techniques developed for disintegrating LCB and enhancing xylose sugars. Further, the transformation of the xylose to value-added products through chemo-catalytic routes was highlighted. In addition, the review also recapitulates the sustainable production of biochemicals by native xylose assimilating microbes and engineering the metabolic pathway to ameliorate biomanufacturing using xylose as the sole carbon source. Overall, this review will give an edge on the bioprocessing of microbial metabolism for the efficient utilization of xylose in the LCB.

Approaches to Enhance Sugar Content in Foods: Is the Date Palm Fruit a Natural Alternative to Sweeteners?

The current levels of added sugars in processed foods impact dental health and contribute to a range of chronic non-communicable diseases, such as overweight, obesity, metabolic syndrome, type 2 diabetes, and cardiovascular diseases. This review presents sugars and sweeteners used in food processing, the current possibility to replace added sugars, and highlights the benefits of using dates as a new natural, nutritious and healthy alternative to synthetic and non-nutritive sweeteners. In the context of environmental sustainability, palm groves afford a propitious habitat for a diverse array of animal species and assume a pivotal social role by contributing to the provisioning of sustenance and livelihoods for local communities. The available literature shows the date as an alternative to added sugars due to its composition in macro and micronutrients, especially in bioactive components (fiber, polyphenols and minerals). Therefore, dates are presented as a health promoter and a preventative for certain diseases with the consequent added value. The use of damaged or unmarketable dates, due to its limited shelf life, can reduce losses and improve the sustainability of date palm cultivation. This review shows the potential use dates, date by-products and second quality dates as sugar substitutes in the production of sweet and healthier foods, in line with broader sustainability objectives and circular economy principles.

Recent Advances in the Biosynthesis of Natural Sugar Substitutes in Yeast

Natural sugar substitutes are safe, stable, and nearly calorie-free. Thus, they are gradually replacing the traditional high-calorie and artificial sweeteners in the food industry. Currently, the majority of natural sugar substitutes are extracted from plants, which often requires high levels of energy and causes environmental pollution. Recently, biosynthesis via engineered microbial cell factories has emerged as a green alternative for producing natural sugar substitutes. In this review, recent advances in the biosynthesis of natural sugar substitutes in yeasts are summarized. The metabolic engineering approaches reported for the biosynthesis of oligosaccharides, sugar alcohols, glycosides, and rare monosaccharides in various yeast strains are described. Meanwhile, some unresolved challenges in the bioproduction of natural sugar substitutes in yeast are discussed to offer guidance for future engineering.

Application of machine learning techniques to the modeling of solubility of sugar alcohols in ionic liquids

The current trend of chemical industries demands green processing, in particular with employing natural substances such as sugar-derived compounds. This matter has encouraged academic and industrial sections to seek new alternatives for extracting these materials. Ionic liquids (ILs) are currently paving the way for efficient extraction processes. To this end, accurate estimation of solubility data is of great importance. This study relies on machine learning methods for modeling the solubility data of sugar alcohols (SAs) in ILs. An initial relevancy analysis approved that the SA-IL equilibrium governs by the temperature, density and molecular weight of ILs, as well as the molecular weight, fusion temperature, and fusion enthalpy of SAs. Also, temperature and fusion temperature have the strongest influence on the SAs solubility in ILs. The performance of artificial neural networks (ANNs), least-squares support vector regression (LSSVR), and adaptive neuro-fuzzy inference systems (ANFIS) to predict SA solubility in ILs were compared utilizing a large databank (647 data points of 19 SAs and 21 ILs). Among the investigated models, ANFIS offered the best accuracy with an average absolute relative deviation (AARD%) of 7.43% and a coefficient of determination (R²) of 0.98359. The best performance of the ANFIS model was obtained with a cluster center radius of 0.435 when trained with 85% of the databank. Further analyses of the ANFIS model based on the leverage method revealed that this model is reliable enough due to its high level of coverage and wide range of applicability. Accordingly, this model can be effectively utilized in modeling the solubilities of SAs in ILs.

Expanding sugar alcohol industry: Microbial production of sugar alcohols and associated chemocatalytic derivatives

Sugar alcohols are polyols that are widely employed in the production of chemicals, pharmaceuticals, and food products. Chemical synthesis of polyols, however, is complex and necessitates the use of hazardous compounds. Therefore, the use of microbes to produce polyols has been proposed as an alternative to traditional synthesis strategies. Many biotechnological approaches have been described to enhancing sugar alcohols production and microbe-mediated sugar alcohol production has the potential to benefit from the availability of inexpensive substrate inputs. Among of them, microbe-mediated erythritol production has been implemented in an industrial scale, but microbial growth and substrate conversion rates are often limited by harsh environmental conditions. In this review, we focused on xylitol, mannitol, sorbitol, and erythritol, the four representative sugar alcohols. The main metabolic engineering strategies, such as regulation of key genes and cofactor balancing, for improving the production of these sugar alcohols were reviewed. The feasible strategies to enhance the stress tolerance of chassis cells, especially thermotolerance, were also summarized. Different low-cost substrates like glycerol, molasses, cellulose hydrolysate, and CO₂ employed for producing these sugar alcohols were presented. Given the value of polyols as precursor platform chemicals that can be leveraged to produce a diverse array of chemical products, we not only discuss the challenges encountered in the above parts, but also envisioned the development of their derivatives for broadening the application of sugar alcohols.

Potential and Restrictions of Food-Waste Valorization through Fermentation Processes

Food losses (FL) and waste (FW) occur throughout the food supply chain. These residues are disposed of on landfills producing environmental issues due to pollutants released into the air, water, and soil. Several research efforts have focused on upgrading FL and FW in a portfolio of added-value products and energy vectors. Among the most relevant research advances, biotechnological upgrading of these residues via fermentation has been demonstrated to be a potential valorization alternative. Despite the multiple investigations performed on the conversion of FL and FW, a lack of comprehensive and systematic literature reviews evaluating the potential of fermentative processes to upgrade different food residues has been identified. Therefore, this article reviews the use of FL and FW in fermentative processes considering the composition, operating conditions, platforms, fermentation product application, and restrictions. This review provides the framework of food residue fermentation based on reported applications, experimental, and theoretical data. Moreover, this review provides future research ideas based on the analyzed information. Thus, potential applications and restrictions of the FL and FW used for fermentative processes are highlighted. In the end, food residues fermentation must be considered a mandatory step toward waste minimization, a circular economy, and the development of more sustainable production and consumption patterns.

Study of Explosion Characteristics and Mechanism of Sucrose Dust

In order to investigate the explosion mechanism of sucrose in the air atmosphere, the explosion intensity under different ignition delay times (IDT), powder input pressures (PIP), and concentrations were studied using a 20L-sphere. The sucrose particles were analyzed in a synchronized thermal analyzer (STA) and scanning electron microscope (SEM). The results are as follows: 1. The DSC curve has two endothermic peaks and one exothermic peak, respectively at T = 180.5 ℃, 510.2 ℃ and 582.6 ℃. 2. The explosion intensity varies with the experiment conditions. The maximum explosion pressure (Pmax) appears when IDT = 90 ms, PIP = 1.5 MPa and concentration = 625 g/m3. 3. The explosive mechanism is a homogeneous combustion mechanism based on particle surface pyrolysis and volatilization. Because of the decomposition, H2, CO, furfural, and other flammable gas-phase products are released, then surface burn appears, which leads to the crystal rupture on account of thermal imbalance, resulting in multiple flame points and a chain explosion. As the temperature of the 20L-sphere rises, more explosive products are released, which causes a rapidly expanding explosion and eventually forms the explosion. This paper can be used as a reference for the prevention of explosion accidents in sucrose production processing.

Rapid, real-time sucrase characterization: Showcasing the feasibility of a one-pot activity assay

Sucrases can modify numerous carbohydrates, and short-chain oligosaccharides produced by the unique transfructosylation activity of levansucrases are promising candidates for the growing sugar substitute market. These compounds could counteract the increasing number of diseases associated with the consumption of high-calorie sugars. Thus, there is great interest in the characterization of novel levansucrases. The commonly used method for sucrase activity determination is to quantify d-glucose released in the sucrose-splitting reaction. This is usually done in a discontinuous mode, i.e., several samples taken from the sucrase reaction are applied to a separately performed d-glucose determination (e.g., GOPOD assay). Employing the newly isolated levansucrase LevS_KK21 from Pseudomonas sp. KK21, the feasibility of a one-pot sucrase characterization was investigated by combining sucrase reaction and GOPOD-based d-glucose determination into a single, continuous assay (Real-time GOPOD). The enzyme was characterized with respect to kinetic parameters, ion dependency, pH value, and reaction temperature in a comparative approach employing Real-time GOPOD and HPLC. High data consistency for all investigated enzyme parameters demonstrated that current processes for sucrase characterization can be considerably accelerated by the continuous assay while maintaining data validity. However, the assay was not applicable at acidic pH, as decolorization of the quinoneimine dye formed during the GOPOD reaction was observed. Overall, the study presents valuable data on the potentials of real-time sucrase activity assessment for an accelerated discovery and characterization of interesting enzymes such as the hereby introduced levansucrase LevS_KK21. Progress in sucrase discovery will finally foster the development of health-promoting sucrose substitutes.

Recycling industrial food wastes for lipid production by oleaginous yeasts Rhodosporidiobolus azoricus and Cutaneotrichosporon oleaginosum

BACKGROUND

Microbial lipids have been emerging as a sustainable alternative to vegetable oils and animal fat to produce biodiesel and industrial relevant chemicals. The use of wastes for microbial processes can represent a way for upgrading low value feedstock to high value products, addressing one of the main goals of circular economy, the reduction of wastes by recycling. Two oleaginous yeasts, Rhodosporidiobolus azoricus and Cutaneotrichosporon oleaginosum, were used in this study to demonstrate the feasibility of the proposed approach.

RESULTS

In this study wastes from industrial food processing, as pumpkin peels and syrup from candied fruits manufacture, were used for yeast cultivation and for lipids production. Evaluation of growth and sugar consumption revealed marked differences between the yeasts in capacity to utilize the main sugars present in the feedstock. In particular, we observed an unexpected limitation in glucose metabolism on mineral defined media by R. azoricus. Both species showed ability to grow and accumulate lipids on media exclusively composed by undiluted pumpkin peel hydrolysate, and R. azoricus was the best performing. By a two-stage process carried out in bioreactor, this species reached a biomass concentration of 45 g/L (dry weight) containing 55% of lipids, corresponding to a lipid concentration of 24 g/L, with a productivity of 0.26 g/L/h and yield of 0.24 g lipids per g of utilized sugar.

CONCLUSIONS

Wastes from industrial food processing were sufficient to completely support yeast growth and to induce lipid accumulation. This study provides strong evidence that the concept of valorisation through the production of lipids from the metabolism of nutrients present in agro-industrial wastes by oleaginous yeasts is promising for implementation of biotechnological processes in a circular economy contest.

Metabolite profiling of a Sargassum micracanthum methanol extract with in vitro efficacy against human head and neck squamous cell carcinoma aggressiveness

OBJECTIVE

Extracts from the brown algae Sargassum micracanthum have documented anti-viral, anti-oxidant, and anti-inflammatory activities as well as potential anti-tumor efficacy against several cancer types. Here, we evaluated the inhibitory effect and molecular mechanisms of methanol extract of S. micracanthum (MESM) on the aggressiveness of human head and neck squamous cell carcinoma (HNSCC) using in vitro cell culture-based models.

DESIGN

To test the potential efficacy of MESM on the migratory and invasive properties of HNSCC cells, we used wound healing, transwell cell migration and invasion assays. Proteome profiling and functional in silico analysis were applied to investigate the possible modes of action by MESM. We also examined the metabolite profiling of MESM using gas chromatography/mass spectrometry.

RESULTS

MESM inhibited the motility of human HNSCC cell lines as well as invasiveness without influencing cell survival. Proteome profiling identified 19 oncogenic proteins significantly downregulated by MESM treatment. Protein-protein interaction network and gene ontology analyses revealed that Tie2 and associated angiogenic signaling pathway components were significantly enriched among these downregulated oncogenic proteins, which was confirmed by validating the reduced Tie2 expression in MESM treatment groups. Metabolite profiling of MESM identified six-carbon sugar alcohols such as D-sorbitol and/or D-mannitol as the main bioactive compounds. D-sorbitol and D-mannitol effectively reduced Tie2 expression and the aggressiveness of human HNSCC cell lines.

CONCLUSIONS

These findings suggest that six-carbon sugar alcohols in MESM have promising anti-cancer efficacy for the treatment of human HNSCC and further identify Tie2 signaling components as potential treatment targets.

Sweet Biotechnology: Enzymatic Production and Digestibility Screening of Novel Kojibiose and Nigerose Analogues

In view of the global pandemic of obesity and related metabolic diseases, there is an increased interest in alternative carbohydrates with promising physiochemical and health-related properties as a potential replacement for traditional sugars. However, our current knowledge is limited to only a small selection of carbohydrates, whereas the majority of alternative rare carbohydrates and especially their properties remain to be investigated. Unraveling their potential properties, like digestibility and glycemic content, could unlock their use in industrial applications. Here, we describe the enzymatic production and in vitro digestibility of three novel glycosides, namely, two kojibiose analogues (i.e., d-Glc_p-α-1,2-d-Gal and d-Glc_p-α-1,2-d-Rib) and one nigerose analogue (i.e., d-Glc_p-α-1,3-l-Ara). These novel sugars were discovered after an intensive acceptor screening with a sucrose phosphorylase originating from Bifidobacterium adolescentis (BaSP). Optimization and upscaling of this process led to roughly 100 g of these disaccharides. Digestibility, absorption, and caloric potential were assessed using brush border enzymes of rat origin and human intestinal Caco-2 cells. The rare disaccharides showed a reduced digestibility and a limited impact on energy metabolism, which was structure-dependent and even more pronounced for the three novel disaccharides in comparison to their respective glucobioses, translating to a low-caloric potential for these novel rare disaccharides.

Development of Low-calorie Functional Yoghurt by Incorporating Mannitol Producing Lactic Acid Bacteria (Leuconostoc pseudomesenteroides) in the Standard Yoghurt Culture

As calorie-consciousness becomes a worldwide phenomenon, demand for low-calorie sweeteners is increasing. Compared to other sugars, the reduced calorific value of mannitol (1.6 kilocalories per gram) finds its application as a sweetener in low-calorie foods. The present study was conducted to develop low-calorie yoghurt by adding lactic acid bacteria (LAB) having significant mannitol production potential. Leuconostoc pseudomesenteroides IMAU:11666 was incorporated to standard yoghurt culture as adjunct culture. As mannitol is a food-grade sweetener with Food and Drug Administration (FDA) endorsement, the newly identified LAB strain can be used to develop low-calorie dairy products with beneficial effects. Side effects of other artificial sweeteners can also be reduced. Significantly high (p≤0.05) mannitol content was observed in functional yoghurt samples T1 (12.27 ± 0.18 g/l) and T2 (14.13 ± 0.30 g/l) with Leuconostoc pseudomesenteroides when compared to control samples. The calorific value obtained for yoghurt samples viz., C1, C2, T1, and T2 (86, 95, 98, and 92 kcal/100g, respectively) was less than control yoghurt C (99 kcal/100 gm). Microbial and chemical quality parameters of the functional yoghurt were in the safe and acceptable zone. On sensory evaluation of yoghurt samples, significantly higher overall and flavor scores were observed for sample T2 with Leuconostoc pseudomesenteroides.

Mannitol Production by Heterofermentative Lactic Acid Bacteria: a Review

Obesity, diabetes, and other cardiovascular diseases are directly related to the high consumption of processed sugars with high caloric content. The current food industry has novel trends related to replacing highly caloric sugars with non-caloric or low-calorie sweeteners. Mannitol, a polyol, represents a suitable substitute because it has a low caloric content and does not induce a glycemic response, which is crucial for diabetic people. Consequently, this polyol has multiple applications in the food, pharmaceutical, and medicine industries. Mannitol can be produced by plant extraction, chemical or enzymatic synthesis, or microbial fermentation. Different in vitro processes have been developed regarding enzymatic synthesis to obtain mannitol from fructose, glucose, or starch-derived substrates. Various microorganisms such as yeast, fungi, and bacteria are applied for microbial fermentation. Among them, heterofermentative lactic acid bacteria (LAB) represent a reliable and feasible alternative due to their metabolic characteristics. In this regard, the yield and productivity of mannitol depend on the culture system, the growing conditions, and the culture medium composition. In situ mannitol production represents a novel approach to decrease the sugar content in food and beverages. Also, genetic engineering offers an interesting option to obtain mannitol-producing strains. This review presents and discusses the most significant advances that have been made in the mannitol production through fermentation by heterofermentative LAB, including the pertinent and critical analysis of culture conditions considering broth composition, reaction systems, and their effects on productivities and yields.

Microbial xylitol production

Xylitol is pentahydroxy sugar alcohol, existing in very trace amount in fruits and vegetables, and finds varied application in industries like food, pharmaceuticals, confectionaries, etc. and is of prime importance to health. Owing to its trace occurrence in nature and considerable increase in market demand that exceeds availability, alternate production through biotechnological and chemical approach is in process. Biochemical production involves substrates like lignocellulosic biomasses and industrial effluents and is an eco-friendly process with high dependency on physico-chemical parameters. Although the chemical processes are faster, high yielding and economical, they have a great limitation as usage of toxic chemicals and thus need to be regulated and replaced by an environment friendly approach. Microbes play a major role in xylitol production through a biotechnological process towards the development of a sustainable system. Major microbes working on assimilation of xylose for production of xylitol include Candida tropicalis, Candida maltose, Bacillus subtilis, Debaromyces hansenii, etc. The present review reports all probable microbial xylitol production biochemical pathways encompassing diverse bioprocesses involved in uptake and conversion of xylose sugars from agricultural residues and industrial effluents. A comprehensive report on xylitol occurrence and biotechnological production processes with varied substrates has been encompassed. KEY POINTS: • Xylitol from agro-industrial waste • Microbial xylose assimilation.

Some Important Metabolites Produced by Lactic Acid Bacteria Originated from Kimchi

Lactic acid bacteria (LAB) have been used for various food fermentations for thousands of years. Recently, LAB are receiving increased attention due to their great potential as probiotics for man and animals, and also as cell factories for producing enzymes, antibodies, vitamins, exopolysaccharides, and various feedstocks. LAB are safe organisms with GRAS (generally recognized as safe) status and possess relatively simple metabolic pathways easily subjected to modifications. However, relatively few studies have been carried out on LAB inhabiting plants compared to dairy LAB. Kimchi is a Korean traditional fermented vegetable, and its fermentation is carried out by LAB inhabiting plant raw materials of kimchi. Kimchi represents a model food with low pH and is fermented at low temperatures and in anaerobic environments. LAB have been adjusting to kimchi environments, and produce various metabolites such as bacteriocins, γ-aminobutyric acid, ornithine, exopolysaccharides, mannitol, etc. as products of metabolic efforts to adjust to the environments. The metabolites also contribute to the known health-promoting effects of kimchi. Due to the recent progress in multi-omics technologies, identification of genes and gene products responsible for the synthesis of functional metabolites becomes easier than before. With the aid of tools of metabolic engineering and synthetic biology, it can be envisioned that LAB strains producing valuable metabolites in large quantities will be constructed and used as starters for foods and probiotics for improving human health. Such LAB strains can also be useful as production hosts for value-added products for food, feed, and pharmaceutical industries. In this review, recent findings on the selected metabolites produced by kimchi LAB are discussed, and the potentials of metabolites will be mentioned.

Enzymes, In Vivo Biocatalysis, and Metabolic Engineering for Enabling a Circular Economy and Sustainability

Since the industrial revolution, the rapid growth and development of global industries have depended largely upon the utilization of coal-derived chemicals, and more recently, the utilization of petroleum-based chemicals. These developments have followed a linear economy model (produce, consume, and dispose). As the world is facing a serious threat from the climate change crisis, a more sustainable solution for manufacturing, i.e., circular economy in which waste from the same or different industries can be used as feedstocks or resources for production offers an attractive industrial/business model. In nature, biological systems, i.e., microorganisms routinely use their enzymes and metabolic pathways to convert organic and inorganic wastes to synthesize biochemicals and energy required for their growth. Therefore, an understanding of how selected enzymes convert biobased feedstocks into special (bio)chemicals serves as an important basis from which to build on for applications in biocatalysis, metabolic engineering, and synthetic biology to enable biobased processes that are greener and cleaner for the environment. This review article highlights the current state of knowledge regarding the enzymatic reactions used in converting biobased wastes (lignocellulosic biomass, sugar, phenolic acid, triglyceride, fatty acid, and glycerol) and greenhouse gases (CO₂ and CH₄) into value-added products and discusses the current progress made in their metabolic engineering. The commercial aspects and life cycle assessment of products from enzymatic and metabolic engineering are also discussed. Continued development in the field of metabolic engineering would offer diversified solutions which are sustainable and renewable for manufacturing valuable chemicals.

Increasing NADPH Availability for Xylitol Production via Pentose-Phosphate-Pathway Gene Overexpression and Embden-Meyerhof-Parnas-Pathway Gene Deletion in Escherichia coli

Cofactor availability is often a rate-limiting factor in the bioconversion of xylose to xylitol. The overexpression of pentose phosphate pathway genes and the deletion of Embden-Meyerhof-Parnas pathway genes can modulate the glucose metabolic flux and increase the intracellular NADPH supply, enabling Escherichia coli cells to produce xylitol from corncob hydrolysates. The effects of zwf and/or gnd overexpression and pfkA, pfkB, and/or pgi deletion on the intracellular redox environment and xylitol production were examined. The NADPH-enhanced strain 2bpgi produced 162 g/L xylitol from corncob hydrolysates after a 76 h fed-batch fermentation in a 15 L bioreactor, which was 13.3% greater than the 143 g/L xylitol produced by the IS5-d control strain. Additionally, the xylitol productivity and xylitol yield per glucose for 2bpgi were 2.13 g/L/h and 2.50 g/g, respectively. Thus, the genetic modifications in 2bpgi significantly enhanced NADPH regeneration, making 2bpgi a potentially useful strain for the industrial-scale production of xylitol from detoxified corncob hydrolysates.

Production of xylitol by Saccharomyces cerevisiae using waste xylose mother liquor and corncob residues

Exorbitant outputs of waste xylose mother liquor (WXML) and corncob residue from commercial‐scale production of xylitol create environmental problems. To reduce the wastes, a Saccharomyces cerevisiae strain tolerant to WXML was conferred with abilities to express the genes of xylose reductase, a xylose‐specific transporter and enzymes of the pentose phosphate pathway. This strain showed a high capacity to produce xylitol from xylose in WXML with glucose as a co‐substrate. Additionally, a simultaneous saccharification and fermentation (SSF) process was designed to use corncob residues and cellulase instead of directly adding glucose as a co‐substrate. Xylitol titer and the productivity were, respectively, 91.0 g l^‐1 and 1.26 ± 0.01 g l^‐1 h^‐1 using 20% WXML, 55 g DCW l^‐1 delignified corncob residues and 11.8 FPU g_cellulose^‐1 cellulase at 35° during fermentation. This work demonstrates the promising strategy of SSF to exploit waste products to xylitol fermentation process.

Promising Pathway of Thermostable Mannitol Dehydrogenase (MtDH) from Caldicellulosiruptor hydrothermalis 108 for D-Mannitol Synthesis

In this study, we conducted the characterization and purification of the thermostable mannitol dehydrogenase (MtDH) from Caldicellulosiruptor hydrothermalis 108. Furthermore, a coupling-enzyme system was designed using (MtDH) from Caldicellulosiruptor hydrothermalis 108 and formate dehydrogenase (FDH) from Ogataea parapolymorpha. The biotransformation system was constructed using Escherichia coli whole cells. The purified enzyme native and subunit molecular masses were 76.7 and 38 kDa, respectively, demonstrating that the enzyme was a dimer. The purified and couple enzyme system results were as follows; the optimum pH for the reduction and the oxidation was 7.0 and 8.0, the optimum temperature was 60 °C, the enzyme activity was inhibited by EDTA and restored by zinc. Additionally, no activity was detected with NADPH and NADP. The purified enzyme showed high catalytic efficiency Kcat 385 s−1, Km 31.8 mM, and kcat/Km 12.1 mM−1 s−1 for D-fructose reduction. Moreover, the purified enzyme retained 80%, 75%, 60%, and 10% of its initial activity after 4 h at 55, 60, 65, and 75 °C, respectively. D-mannitol yield was achieved via HPLC. Escherichia coli are the efficient biotransformation mediator to produce D-mannitol (byproducts free) at high temperature and staple pH, resulting in a significant D-mannitol conversation (41 mg/mL) from 5% D-fructose.

Product Control and Insight into Conversion of C6 Aldose Toward C2, C4 and C6 Alditols in One-Pot Retro-Aldol Condensation and Hydrogenation Processes

Alcohols have a wide range of applicability, and their functions vary with the carbon numbers. C6 and C4 alditols are alternative of sweetener, as well as significant pharmaceutical and chemical intermediates, which are mainly obtained through the fermentation of microorganism currently. Similarly, as a bulk chemical, C2 alditol plays a decisive role in chemical synthesis. However, among them, few works have been focused on the chemical production of C4 alditol yet due to its difficult accumulation. In this paper, under a static and semi-flowing procedure, we have achieved the product control during the conversion of C6 aldose toward C6 alditol, C4 alditol and C2 alditol, respectively. About C4 alditol yield of 20 % and C4 plus C6 alditols yield of 60 % are acquired in the one-pot conversion via a cascade retro-aldol condensation and hydrogenation process. Furthermore, in the semi-flowing condition, the yield of ethylene glycol is up to 73 % thanks to its low instantaneous concentration.

New insights into the molecular mechanism behind mannitol and erythritol fructosylation by β-fructofuranosidase from Schwanniomyces occidentalis

The β-fructofuranosidase from Schwanniomyces occidentalis (Ffase) is a useful biotechnological tool for the fructosylation of different acceptors to produce fructooligosaccharides (FOS) and fructo-conjugates. In this work, the structural determinants of Ffase involved in the transfructosylating reaction of the alditols mannitol and erythritol have been studied in detail. Complexes with fructosyl-erythritol or sucrose were analyzed by crystallography and the effect of mutational changes in positions Gln-176, Gln-228, and Asn-254 studied to explore their role in modulating this biocatalytic process. Interestingly, N254T variant enhanced the wild-type protein production of fructosyl-erythritol and FOS by \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sim$$\end{document}∼ 30% and 48%, respectively. Moreover, it produced neokestose, which represented \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sim$$\end{document}∼ 27% of total FOS, and yielded 31.8 g l⁻¹ blastose by using glucose as exclusive fructosyl-acceptor. Noteworthy, N254D and Q176E replacements turned the specificity of Ffase transferase activity towards the synthesis of the fructosylated polyols at the expense of FOS production, but without increasing the total reaction efficiency. The results presented here highlight the relevance of the pair Gln-228/Asn-254 for Ffase donor-sucrose binding and opens new windows of opportunity for optimizing the generation of fructosyl-derivatives by this enzyme enhancing its biotechnological applicability.

Recent Advances in Producing Sugar Alcohols and Functional Sugars by Engineering Yarrowia lipolytica

The sugar alcohols and functional sugars have wide applications in food, pharmaceutical, and chemical industries. However, the smaller quantities of natural occurring sugar alcohols and functional sugars restricted their applications. The enzymatic and whole-cell catalyst production is emerging as the predominant alternatives. The properties of Yarrowia lipolytica make it a promising sugar alcohol and functional sugar producer. However, there are still some issues to be resolved. As there exist reviews about the chemical structures, physicochemical properties, biological functions, applications, and biosynthesis of sugar alcohols and/or functional sugars in Y. lipolytica, this mini review will not only update the recent advances in enzymatic and microbial production of sugar alcohols (erythritol, D-threitol, and xylitol) and functional sugars (isomaltulose, trehalose, fructo-oligosaccharides, and galacto-oligosaccharides) by using recombinant Y. lipolytica but also focus on the studies of gene discovery, pathway engineering, expanding substrate scope, bioprocess engineering, and novel breeding methods to resolve the aforementioned issues.

Bioprospecting of microbial strains for biofuel production: metabolic engineering, applications, and challenges

The issues of global warming, coupled with fossil fuel depletion, have undoubtedly led to renewed interest in other sources of commercial fuels. The search for renewable fuels has motivated research into the biological degradation of lignocellulosic biomass feedstock to produce biofuels such as bioethanol, biodiesel, and biohydrogen. The model strain for biofuel production needs the capability to utilize a high amount of substrate, transportation of sugar through fast and deregulated pathways, ability to tolerate inhibitory compounds and end products, and increased metabolic fluxes to produce an improved fermentation product. Engineering microbes might be a great approach to produce biofuel from lignocellulosic biomass by exploiting metabolic pathways economically. Metabolic engineering is an advanced technology for the construction of highly effective microbial cell factories and a key component for the next-generation bioeconomy. It has been extensively used to redirect the biosynthetic pathway to produce desired products in several native or engineered hosts. A wide range of novel compounds has been manufactured through engineering metabolic pathways or endogenous metabolism optimizations by metabolic engineers. This review is focused on the potential utilization of engineered strains to produce biofuel and gives prospects for improvement in metabolic engineering for new strain development using advanced technologies.

Bio-synthesis of food additives and colorants-a growing trend in future food

Food additives and colorants are extensively used in the food industry to improve food quality and safety during processing, storage and packing. Sourcing of these molecules is predominately through three means: extraction from natural sources, chemical synthesis, and bio-production, with the first two being the most utilized. However, growing demands for sustainability, safety and "natural" products have renewed interest in using bio-based production methods. Likewise, the move to more cultured foods and meat alternatives requires the production of new additives and colorants. The production of bio-based food additives and colorants is an interdisciplinary research endeavor and represents a growing trend in future food. To highlight the potential of microbial hosts for food additive and colorant production, we focus on current advances for example molecules based on their utilization stage and bio-production yield as follows: (I) approved and industrially produced with high titers; (II) approved and produced with decent titers (in the g/L range), but requiring further engineering to reduce production costs; (III) approved and produced with very early stage titers (in the mg/L range); and (IV) new/potential candidates that have not been approved but can be sourced through microbes. Promising approaches, as well as current challenges and future directions will also be thoroughly discussed for the bioproduction of these food additives and colorants.

Archaeal hyperthermostable mannitol dehydrogenases: A promising industrial enzymes for d-mannitol synthesis

Recently, the term healthy lifestyle connected to low-calorie diets, although it is not possible to get rid of added sugars as a source of energy, despite the close relation of added sugars to some diseases such as obesity, diabetes, etc. As a result, the sweetener market has flourished, which has led to increased demand for natural sweeteners such as polyols, including d-mannitol. Various methods have been developed to produce d-mannitol to achieve high productivity and low cost. In particular, metabolic engineering for d-mannitol considers one of the most promising approaches for d-mannitol production on the industrial scale. To date, the chemical process is not ideal for large-scale production because of its multistep mechanism involving hydrogenation and high cost. In this review, we highlight and present a comparative evaluation of the biochemical parameters that affecting d-mannitol synthesis from Thermotoga neapolitana and Thermotoga maritima mannitol dehydrogenase (MtDH) as a potential contribution for d-mannitol bio-synthesis. These species were selected because purified mannitol dehydrogenases from both strains have been reported to produce d-mannitol with no sorbitol formation under temperatures (90-120 °C).

Lignocellulosic Biomass as a Substrate for Oleaginous Microorganisms: A Review

Microorganisms capable of accumulating lipids in high percentages, known as oleaginous microorganisms, have been widely studied as an alternative for producing oleochemicals and biofuels. Microbial lipid, so-called Single Cell Oil (SCO), production depends on several growth parameters, including the nature of the carbon substrate, which must be efficiently taken up and converted into storage lipid. On the other hand, substrates considered for large scale applications must be abundant and of low acquisition cost. Among others, lignocellulosic biomass is a promising renewable substrate containing high percentages of assimilable sugars (hexoses and pentoses). However, it is also highly recalcitrant, and therefore it requires specific pretreatments in order to release its assimilable components. The main drawback of lignocellulose pretreatment is the generation of several by-products that can inhibit the microbial metabolism. In this review, we discuss the main aspects related to the cultivation of oleaginous microorganisms using lignocellulosic biomass as substrate, hoping to contribute to the development of a sustainable process for SCO production in the near future.

Encapsulation of Mannose-6-phosphate Isomerase in Yeast Spores and Its Application in l-Ribose Production

A mannose-6-phosphate isomerase (MPI) from Geobacillus thermodenitrificans was expressed and successfully encapsulated into the Saccharomyces cerevisiae spores. Our results demonstrated that compared to the free enzyme, the MPI triple mutant encapsulated in osw2Δ spores exhibited much preferred enzymatic properties, such as enhanced catalytic activity, excellent reusability, thermostability, and tolerance to various harsh conditions. In combination with an l-arabinose isomerase (AI) also from G. thermodenitrificans, this technique of spore encapsulation was applied for producing a high-value rare sugar l-ribose from biomass-derived l-arabinose. Using a 10 mL reaction system, 350 mg of l-ribose was produced from 1 g of l-arabinose with a conversion yield of 35% by repeatedly reacting with 200 mg of AI-encapsulated spores and 300 mg of MPI-encapsulated spores. This study provides a very useful and concise approach for the synthesis of rare sugars and other useful compounds.

Photosynthetic Reduction of Xylose to Xylitol Using Cyanobacteria

Photosynthetic generation of reducing power makes cyanobacteria an attractive host for biochemical reduction compared to cell-free and heterotrophic systems, which require burning of additional resources for the supply of reducing equivalent. Here, using xylitol synthesis as an example, efficient uptake and reduction of xylose photoautotrophically in Synechococcus elongatus PCC7942 are demonstrated upon introduction of an effective xylose transporter from Escherichia coli (Ec-XylE) and the NADPH-dependent xylose reductase from Candida boidinii (Cb-XR). Simultaneous activation of xylose uptake and matching of cofactor specificity enabled an average xylitol yield of 0.9 g g^-1 xylose and a maximum productivity of about 0.15 g L^-1 day^-1 OD^-1 with increased level of xylose supply. While long-term cellular maintenance still appears challenging, high-density conversion of xylose to xylitol using concentrated resting cell further pushes the titer of xylitol formation to 33 g L^-1 in six days with 85% of maximum theoretical yield. While the results show that the unknown dissipation of xylose can be minimized when coupled to a strong reaction outlet, it remains to be the major hurdle hampering the yield despite the reported inability of cyanobacteria to metabolize xylose.

Recent advances in the biotechnological production of erythritol and mannitol

Dietary habits that include an excess of added sugars have been strongly associated with an increased risk of obesity, heart disease, diabetes, and tooth decay. With this association in view, modern food systems aim to replace added sugars with low calorie sweeteners, such as polyols. Polyols are generally not carcinogenic and do not trigger a glycemic response. Furthermore, owing to the absence of the carbonyl group, they are more stable compared to monosaccharides and do not participate in Maillard reactions. As such, since polyols are stable at high temperatures, and they do not brown or caramelize when heated. Therefore, polyols are widely used in the diets of hypocaloric and diabetic patients, as well as other specific cases where controlled caloric intake is required. In recent years, erythritol and mannitol have gained increased importance, especially in the food and pharmaceutical industries. In these areas, research efforts have been made to improve the productivity and yield of the two polyols, relying on biotechnological manufacturing methods. The present review highlights the recent advances in the biotechnological production of erythritol and mannitol and summarizes the benefits of using the two polyols in the food and pharmaceutical industries.

Microbial and enzymatic strategies for the production of L-ribose

L-Ribose is a non-naturally occurring pentose that recently has become known for its potential application in the pharmaceutical industry, as it is an ideal starting material for use in synthesizing L-nucleosides analogues, an important class of antiviral drugs. In the past few decades, the synthesis of L-ribose has been mainly undertaken through the chemical route. However, chemical synthesis of L-ribose is difficult to achieve on an industrial scale. Therefore, the biotechnological production of L-ribose has gained considerable attention, as it exhibits many merits over the chemical approaches. The present review focuses on various biotechnological strategies for the production of L-ribose through microbial biotransformation and enzymatic catalysis, and in particular on an analysis and comparison of the synthetic methods and different enzymes. The physiological functions and applications of L-ribose are also elucidated. In addition, different sugar isomerases involved in the production of L-ribose from a number of sources are discussed in detail with regard to their biochemical properties. Furthermore, analysis of the separation issues of L-ribose from the reaction solution and different purification methods is presented.Key points • l -Arabinose, l -ribulose and ribitol can be used to produce l -ribose by enzymes. • Five enzymes are systematically introduced for production of l -ribose. • Microbial transformation and enzymatic methods are promising for yielding l -ribose.

Valorization of Crude Glycerol, Residue Deriving from Biodiesel- Production Process, with the Use of Wild-type New Isolated Yarrowia lipolytica Strains: Production of Metabolites with Pharmaceutical and Biotechnological Interest

BACKGROUND & OBJECTIVE

Crude glycerol (Glol), used as substrate for screening eleven natural Yarrowia lipolytica strains in shake-flask experiments. Aim of this study was to assess the ability of the screened strains to produce biomass (dry cell weight; X), lipid (L), citric acid (Cit), mannitol (Man), arabitol (Ara) and erythritol (Ery), compounds presenting pharmaceutical and biotechnological interest, in glycerol-based nitrogen-limited media, in which initial glycerol concentration had been adjusted to 40 g/L.

METHODS

Citric acid may find use in biomedical engineering (i.e. drug delivery, tissue engineering, bioimaging, orthopedics, medical device coating, wound dressings). Polyols are considered as compounds with non-cariogenic and less calorigenic properties as also with low insulin-mediated response. Microbial lipids containing polyunsaturated fatty acids (PUFA) are medically and dietetically important (selective pharmaceutical and anticancer properties, aid fetal brain development, the sight function of the eye, hormonal balance and the cardio-vascular system, prevent reasons leading to type-2 diabetes, present healing and anti-inflammatory effects).

RESULTS

All strains presented satisfactory microbial growth (Xmax=5.34-6.26 g/L) and almost complete substrate uptake. The principal metabolic product was citric acid (Citmax=8.5-31.7 g/L). Production of cellular lipid reached the values of 0.33-0.84 g/L. Polyols were also synthesized as strain dependent compounds (Manmax=2.8-6.1 g/L, Aramax ~2.0 g/L, Erymax= 0.5-3.8 g/L). The selected Y. lipolytica strain ACA-DC 5029 presented satisfactory growth along with synthesis of citric acid and polyols, thus, was further grown on media presenting an increased concentration of Glol~75 g/L. Biomass, lipid and citric acid production presented significant enhancement (Xmax=11.80 g/L, Lmax=1.26 g/L, Citmax=30.8 g/L), but conversion yield of citric acid produced per glycerol consumed was decreased compared to screening trials. Erythritol secretion (Erymax=15.6 g/L) was highly favored, suggesting a shift of yeast metabolism from citric acid accumulation towards erythritol production. Maximum endopolysaccharides (IPS) concentration was 4.04 g/L with yield in dry weight 34.2 % w/w.

CONCLUSION

Y. lipolytica strain ACA-YC 5029 can be considered as a satisfactory candidate grown in high concentrations of crude glycerol to produce added-value compounds that interest pharmaceutical and biotechnology industries.

Organocatalytic Michael Addition to (D)-Mannitol-Derived Enantiopure Nitroalkenes: A Valuable Strategy for the Synthesis of Densely Functionalized Chiral Molecules

Carbohydrates are abundant renewable resources and are a feedstock for green chemistry and sustainable synthesis of the future. Among the hexoses and the pentoses present in biomass, mannitol was selected in the present project as a valuable platform, directly available from the chiral pool, to build highly functionalized molecules. Starting from (R)-2,3-O-cyclohexylidene glyceraldehyde, which is easily prepared in a large scale from D-mannitol, an enantiopure chiral nitro alkene was prepared by reaction with nitromethane, and its reactivity studied. Organocatalytic Michael addition of dimethyl malonate, β-keto esters, and other nucleophiles on the nitro alkene afforded high stereoselectivity and densely functionalized chiral molecules, which were further synthetically developed, leading to five-membered lactones and bicyclic lactams. Preliminary studies showed that the metal-free catalytic reaction on the chiral nitro alkene can be performed under continuous flow conditions, thus enabling the use of (micro)mesofluidic systems for the preparation of enantiomerically pure organic molecules from the chiral pool.

Catalytic amidation of natural and synthetic polyol esters with sulfonamides

Triacylglycerides are naturally abundant and renewable feedstock for biofuels and chemicals. In this report, these seemingly stable compounds are shown to be reactive toward a variety of sulfonamides under Lewis acid catalysis. In these reactions, alkyl C(sp³)–O bonds are cleaved and C–N bonds constructed, providing functionalized value-added products directly from renewables. Mechanistic and scope study demonstrate that the origin of the reactivity could be the synergy of Lewis acid catalysis and neighboring group participation by the 2- or 3-acyloxy or acylamido group with respect to the reactive site. Since poly(ethylene terephthalate) (PET), a widely available consumer polyester, also contains 1,2-diol diester group as the repeating unit in the main chain, this chemistry can also be applied to efficient depolymerization of PET.

Triacylglycerides are naturally abundant and renewable feedstock, but their chemical transformation is hindered by their stability. Here, under Lewis acid catalysis, the authors report the selective alkyl C–O bond conversion of triglycerides into C–N bonds and even apply this efficient method to PET depolymerization.

Production of l-Ribulose Using an Encapsulated l-Arabinose Isomerase in Yeast Spores

The rare sugar l-ribulose is produced from the abundant sugar l-arabinose by enzymatic conversion. An l-arabinose isomerase (AI) from Geobacillus thermodenitrificans was efficiently expressed and encapsulated in Saccharomyces cerevisiae spores. Deletion of the yeast OSW2 gene, which causes a mild defect in the integrity of the spore wall, substantially improved the activity of encapsulated AI, without damaging its superior enzymatic properties of thermostability, pH tolerance,and resistance toward SDS and proteinase treatments. In a 10 mL reaction, 100 mg of dry AI encapsulated in spores produced 250 mg of l-ribulose from 1 g of l-arabinose, indicating a 25% conversion rate. Notably, the product of l-ribulose was directly purified from the reaction solution with an approximately 91% recovery using a Ca²⁺ ion exchange column. Our results describe not only a facile approach for the production of l-ribulose but also a useful strategy for the enzymatic conversion of rare sugars in "Izumoring".

Impact of polyols on Oral microbiome of Estonian schoolchildren

BACKGROUND

Oral microbiome has significant impact on both oral and general health. Polyols have been promoted as sugar substitutes in prevention of oral diseases. We aimed to reveal the effect of candies containing erythritol, xylitol or control (sorbitol) on salivary microbiome.

METHODS

Ninety children (11.3 ± 0.6 years) consumed candies during 3 years. Microbial communities were profiled using Illumina HiSeq 2000 sequencing and real-time PCR.

RESULTS

The dominant phyla in saliva were Firmicutes (39.1%), Proteobacteria (26.1%), Bacteroidetes (14.7%), Actinobacteria (12%) and Fusobacteria (6%). The microbiome of erythritol group significantly differed from that of the other groups. Both erythritol and xylitol reduced the number of observed bacterial phylotypes in comparison to the control group. The relative abundance of the genera Veillonella, Streptococcus and Fusobacterium were higher while that of Bergeyella lower after erythritol intervention when comparing with control. The lowest prevalence of caries-related mutans streptococci corresponded with the lowest clinical caries markers in the erythritol group.

CONCLUSIONS

Daily consumption of erythritol, xylitol or control candies has a specific influence on the salivary microbiome composition in schoolchildren. Erythritol is associated with the lowest prevalence of caries-related mutans streptococci and the lowest levels of clinical caries experience.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT01062633.

Co-utilization of acidified glycerol pretreated-sugarcane bagasse for microbial oil production by a novel Rhodosporidium strain

Acidified glycerol pretreatment is very effective to deconstruct lignocellulosics for producing glucose. Co-utilization of pretreated biomass and residual glycerol to bioproducts could reduce the costs associated with biomass wash and solvent recovery. In this study, a novel strain Rhodosporidium toruloides RP 15, isolated from sugarcane bagasse, was selected and tested for coconversion of pretreated biomass and residual glycerol to microbial oils. In the screening trails, Rh. toruloides RP 15 demonstrated the highest oil production capacity on glucose, xylose, and glycerol among the 10 strains. At the optimal C:N molar ratio of 140:1, this strain accumulated 56.7, 38.3, and 54.7% microbial oils based on dry cell biomass with 30 g/L glucose, xylose, and glycerol, respectively. Furthermore, sugarcane bagasse medium containing 32.6 g/L glucose from glycerol-pretreated bagasse and 23.4 g/L glycerol from pretreatment hydrolysate were used to produce microbial oils by Rh. toruloides RP 15. Under the preliminary conditions without pH control, this strain produced 7.7 g/L oil with an oil content of 59.8%, which was comparable or better than those achieved with a synthetic medium. In addition, this strain also produced 3.5 mg/L carotenoid as a by-product. It is expected that microbial oil production can be significantly improved through process optimization.

Production of Added-Value Chemical Compounds through Bioconversions of Olive-Mill Wastewaters Blended with Crude Glycerol by a Yarrowia lipolytica Strain

Olive mill wastewaters (OMW) are the major effluent deriving from olive oil production and are considered as one of the most challenging agro-industrial wastes to treat. Crude glycerol is the main by-product of alcoholic beverage and oleochemical production activities including biodiesel production. The tremendous quantities of glycerol produced worldwide represent a serious environmental challenge. The aim of this study was to assess the ability of Yarrowia lipolytica strain ACA-DC 5029 to grow on nitrogen-limited submerged shake-flask cultures, in crude glycerol and OMW blends as well as in media with high initial glycerol concentration and produce biomass, cellular lipids, citric acid and polyols. The rationale of using such blends was the dilution of concentrated glycerol by OMW to (partially or fully) replace process tap water with a wastewater stream. The strain presented satisfactory growth in blends; citric acid production was not affected by OMW addition (Citmax~37.0 g/L, YCit/Glol~0.55 g/g) and microbial oil accumulation raised proportionally to OMW addition (Lmax~2.0 g/L, YL/X~20% w/w). Partial removal of color (~30%) and phenolic compounds (~10% w/w) of the blended media occurred. In media with high glycerol concentration, a shift towards erythritol production was noted (Erymax~66.0 g/L, YEry/Glol~0.39 g/g) simultaneously with high amounts of produced citric acid (Citmax~79.0 g/L, YCit/Glol~0.46 g/g). Fatty acid analysis of microbial lipids demonstrated that OMW addition in blended media and in excess carbon media with high glycerol concentration favored oleic acid production.