Assessment of Cosmetic and Dermatological Properties and Safety of Use of Model Skin Tonics with Kombucha-Fermented Red Berry Extracts.

Kombucha is a health-promoting beverage that is produced by fermenting sweetened tea using symbiotic cultures of bacteria belonging to the genus Acetobacter, Gluconobacter, and yeast of the genus Saccharomyces. This study compared the cosmetic and dermatological properties of the extracts of the following redberries: R. rubrum, F. vesca, and R. idaeus, and their ferments, which were obtained by fermentation for 10 and 20 days using tea fungus. For this purpose, the fermented and non-fermented extracts were compared in terms of their chemical composition using the HPLC/ESI-MS chromatographic method, demonstrating the high content of biologically active compounds that were present in the ferments. The antioxidant activity of the tested samples was evaluated using DPPH and ABTS tests, as well as by evaluating the scavenging of the external and intracellular free radicals. The cytotoxicity of the extracts and the ferments, as well as the cosmetic formulations, were also determined by conducting Alamar Blue and Neutral Red tests assessing the cell viability and metabolism using skin cell lines: fibroblasts and keratinocytes. In addition, application tests were conducted showing the positive effects of the model cosmetic tonics on the TEWL, the skin hydration, and the skin pH. The results indicate that both the extracts and the ferments that were obtained from kombucha can be valuable ingredients in cosmetic products.

Comparing in planta accumulation with microbial routes to set targets for a cost-competitive bioeconomy.

Plants and microbes share common metabolic pathways for producing a range of bioproducts that are potentially foundational to the future bioeconomy. However, in planta accumulation and microbial production of bioproducts have never been systematically compared on an economic basis to identify optimal routes of production. A detailed technoeconomic analysis of four exemplar compounds (4-hydroxybenzoic acid [4-HBA], catechol, muconic acid, and 2-pyrone-4,6-dicarboxylic acid [PDC]) is conducted with the highest reported yields and accumulation rates to identify economically advantaged platforms and breakeven targets for plants and microbes. The results indicate that in planta mass accumulation ranging from 0.1 to 0.3 dry weight % (dwt%) can achieve costs comparable to microbial routes operating at 40 to 55% of maximum theoretical yields. These yields and accumulation rates are sufficient to be cost competitive if the products are sold at market prices consistent with specialty chemicals ($20 to $50/kg). Prices consistent with commodity chemicals will require an order-of-magnitude-greater accumulation rate for plants and/or yields nearing theoretical maxima for microbial production platforms. This comparative analysis revealed that the demonstrated accumulation rates of 4-HBA (3.2 dwt%) and PDC (3.0 dwt%) in engineered plants vastly outperform microbial routes, even if microbial platforms were to reach theoretical maximum yields. Their recovery and sale as part of a lignocellulosic biorefinery could enable biofuel prices to be competitive with petroleum. Muconic acid and catechol, in contrast, are currently more attractive when produced microbially using a sugar feedstock. Ultimately, both platforms can play an important role in replacing fossil-derived products.

Safety assessment of white colony-forming yeasts in kimchi.

White colony-forming yeasts (WCFYs) have been reported to form a white colony on the surface of kimchi, resulting in the deterioration of kimchi sensory quality. However, toxicity of WCFY has rarely been studied. Thus, to evaluate the safety of WCFY (i.e., Kazachstania servazzii, Candia sake, and Pichia kudriavzevii), we conducted cell and animal experiments as well as genomic analysis. In vitro studies indicated that WCFY did not induce cytotoxic responses such as lactate dehydrogenase release, excessive oxidative stress, and mitochondrial damage at concentrations of up to 2.5 × 105 CFU/mL in human intestinal and liver cells. In animal studies using rats (single-dose and 14-day repeated-dose oral toxicity studies), WCFY did not induce death, clinical signs of toxicity, histological alterations of the liver, or increases in the expression of pro-inflammatory cytokines nor cytochrome P450-2E1 in liver tissue at concentrations of up to 5 × 108 CFU/head/day. Genomic analysis revealed that P. kudriavzevii did not harbor genes related to toxicity and antimicrobial resistance. Taken together, our data suggest that exposure to WCFY through kimchi intake did not induce toxic response in the Caco-2, HepG2, and Sprague-Dawley rats. The current work provides evidence for the safety of accidental major WCFY ingestion via kimchi.

Assessment of quorum sensing effects of tyrosol on fermentative performance by chief ethnic fermentative yeasts from northeast India.

AIM: Tyrosol, a quorum sensing molecule in yeasts, was reported to reduce lag phase and induces hyphae formation during cell proliferation. However, evidence of any enhancing effect of tyrosol in cellular proliferation within fermentative environment is unclear. In this investigation, selected yeast cells were assessed for their ability to synthesize tyrosol followed by examining the role of the molecule during fermentation. METHODS AND RESULTS: Tyrosols were characterized in four fermentative yeasts viz., Saccharomyces cerevisiae, Wickerhamomyces anomalus, Candida glabrata and Candida tropicalis isolated from traditional fermentative cakes of northeast India. All the isolates synthesized tyrosol while C. tropicalis exhibited filamentous growth in response to tyrosols retrieved from other isolates. Purified tyrosols showed protective behaviour in C. tropicalis and S. cerevisiae under ethanol mediated oxidative stress. During fermentation, tyrosol significantly enhanced growth of W. anomalus in starch medium while C. tropicalis exhibited growth enhancement in starch and glucose sources. The chief fermentative yeast S. cerevisiae showed notable enhancement in fermentative capacity in starch medium under the influence of tyrosol con-commitment of ethanol production. CONCLUSION: The study concludes that tyrosol exerts unusual effect in cellular growth and fermentative ability of both Saccharomyces and non-Saccharomyces yeasts. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of expression of tyrosol by non-conventional yeasts, where the molecule was found to exert enhancing effect during fermentation, thereby augmenting the process of metabolite production during traditional fermentation.

Microbiological assessment of liquid feed for finisher pigs on commercial pig units.

AIMS: To investigate the microbiological and nutritional quality of liquid finisher pig feed on commercial production units and the factors influencing this. METHODS AND RESULTS: Microbiological and physio-chemical analyses were performed on liquid feed sampled from the mixing tank and troughs of the finisher section of eight commercial pig units. Lactic acid bacteria, yeast and Escherichia coli counts, as well as lactic acid, ethanol and acetate concentrations were higher in residual feed sampled from the troughs compared with mixing tank samples (P < 0·001). Feed pH, as well as lysine, methionine and threonine concentrations and gross energy were all lower in the residual trough samples (P < 0·001). Liquid co-products reduced E. coli counts in the residual trough samples (P < 0·05), pH in the mixing tank (P < 0·01) and fresh trough samples (P < 0·05) and mould counts at all three sampling locations (P < 0·01) but sanitation practices had no impact. CONCLUSIONS: Even when considered unfermented, a considerable degree of spontaneous fermentation occurs in liquid feed, with resultant negative effects on nutritional quality. SIGNIFICANCE AND IMPACT OF THE STUDY: This is one of the first studies showing that uncontrolled fermentation of fresh liquid pig feed is commonplace on commercial units, highlighting the need for implementation of suitable control strategies.

SAlign-a structure aware method for global PPI network alignment.

BACKGROUND: High throughput experiments have generated a significantly large amount of protein interaction data, which is being used to study protein networks. Studying complete protein networks can reveal more insight about healthy/disease states than studying proteins in isolation. Similarly, a comparative study of protein-protein interaction (PPI) networks of different species reveals important insights which may help in disease analysis and drug design. The study of PPI network alignment can also helps in understanding the different biological systems of different species. It can also be used in transfer of knowledge across different species. Different aligners have been introduced in the last decade but developing an accurate and scalable global alignment algorithm that can ensures the biological significance alignment is still challenging. RESULTS: This paper presents a novel global pairwise network alignment algorithm, SAlign, which uses topological and biological information in the alignment process. The proposed algorithm incorporates sequence and structural information for computing biological scores, whereas previous algorithms only use sequence information. The alignment based on the proposed technique shows that the combined effect of structure and sequence results in significantly better pairwise alignments. We have compared SAlign with state-of-art algorithms on the basis of semantic similarity of alignment and the number of aligned nodes on multiple PPI network pairs. The results of SAlign on the network pairs which have high percentage of proteins with available structure are 3-63% semantically better than all existing techniques. Furthermore, it also aligns 5-14% more nodes of these network pairs as compared to existing aligners. The results of SAlign on other PPI network pairs are comparable or better than all existing techniques. We also introduce [Formula: see text], a Monte Carlo based alignment algorithm, that produces multiple network alignments with similar semantic similarity. This helps the user to pick biologically meaningful alignments. CONCLUSION: The proposed algorithm has the ability to find the alignments that are more biologically significant/relevant as compared to the alignments of existing aligners. Furthermore, the proposed method is able to generate alternate alignments that help in studying different genes/proteins of the specie.

The Assessment of Diet Contaminated with Aflatoxin B1 in Juvenile Turbot (Scophthalmus maximus) and the Evaluation of the Efficacy of Mitigation of a Yeast Cell Wall Extract.

This study aimed to investigate the effects of dietary AFB1 on growth performance, health, intestinal microbiota communities and AFB1 tissue residues of turbot and evaluate the mitigation efficacy of yeast cell wall extract, Mycosorb® (YCWE) toward AFB1 contaminated dietary treatments. Nine experimental diets were formulated: Diet 1 (control): AFB1 free; Diets 2-5 or Diets 6-9: 20 µg AFB1/kg diet or 500 µg AFB1/kg diet + 0%, 0.1%, 0.2%, or 0.4% YCWE, respectively). The results showed that Diet 6 significantly decreased the concentrations of TP, GLB, C3, C4, T-CHO, TG but increased the activities of AST, ALT in serum, decreased the expressions of CAT, SOD, GPx, CYP1A but increased the expressions of CYP3A, GST-ζ1, p53 in liver. Diet 6 increased the AFB1 residues in serum and muscle, altered the intestinal microbiota composition, decreased the bacterial community diversity and the abundance of some potential probiotics. However, Diet 8 and Diet 9 restored the immune response, relieved adverse effects in liver, lowered the AFB1 residues in turbot tissues, promoted intestinal microbiota diversity and lowered the abundance of potentially pathogens. In conclusion, YCWE supplementation decreased the health effects of AFB1 on turbot, restoring biomarkers closer to the mycotoxin-free control diet.

Quantitative assessment of chaperone binding to amyloid aggregates identifies specificity of Hsp40 interaction with yeast prion fibrils.

Yeast self-perpetuating protein aggregates (yeast prions) provide a framework to investigate the interaction of misfolded proteins with the protein quality control machinery. The major component of this system that facilitates propagation of all known yeast amyloid prions is the Hsp104 chaperone that catalyzes fibril fragmentation. Overproduction of Hsp104 cures some yeast prions via a fragmentation-independent mechanism. Importantly, major cytosolic chaperones of the Hsp40 group, Sis1 and Ydj1, oppositely affect yeast prion propagation, and are capable of stimulating different activities of Hsp104. In this work, we developed a quantitative method to investigate the Hsp40 binding to amyloid aggregates. We demonstrate that Sis1 binds fibrils formed by the Sup35NM protein with higher affinity compared to Ydj1. Moreover, the interaction of Sis1 with the fibrils formed by the other yeast prion protein, Rnq1, is orders of magnitude weaker. We show that the deletion of the dimerization domain of Sis1 (crucial for the curing of [PSI+] by excess Hsp104) decreases its affinity to both Sup35NM and Rnq1 fibrils. Taken together, these results suggest that tight binding of Hsp40 to the amyloid fibrils is likely to enhance aggregate malpartition instead of fibril fragmentation.

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.

Profiling of carbohydrates in commercial beers and their influence on beer quality.

BACKGROUND: The carbohydrates in beer play an important role as they are essential for fermentation. Any change in their composition may influence the sensory characteristics of the beer and so their determination is of great interest. This study compares the carbohydrates in three types of commercial beer - barley malt beer, wheat beer, and barley malt beer with adjuncts - and examines their influence on beer quality, which is important for selecting raw ingredients and production conditions, and for quality control. RESULTS: Among the oligosaccharides in three types of beer, raffinose was the most, followed by maltotetraose, maltotriose and maltose. Monosaccharides were only present in small amounts. Dextrin, oligosaccharides with 2-6 polymerization degree and non-starch polysaccharides (NSP) make up 15.90-34.83%, 17.59-38.63%, and 2.33-7.47% of the total carbohydrates in beer, respectively. The dextrin content and NSP content were significantly (P < 0.05) different in wheat beer and barley malt beer, and their content was significantly (P < 0.01) correlated with the content of extracts in beer. Non-starch polysaccharide, dextrin, trisaccharide, and tetrasaccharide content significantly (P < 0.05) correlated with beer viscosity. These beer samples could be categorized clearly into three groups by principal component analysis. CONCLUSION: The oligosaccharides in beer reflect yeast utilization, depending on the type of beer. Dextrin, oligosaccharides with 2-4 polymerization, and NSP, were major carbohydrates in beer. Their composition and concentration influenced its characteristics and quality, and played an important role in the discrimination of different beer types. © 2020 Society of Chemical Industry.

Oleaginous yeasts for sustainable lipid production-from biodiesel to surf boards, a wide range of "green" applications.

A growing world population and a growing number of applications for vegetable oils are generating an increasing demand for these oils, causing serious environmental problems. A sustainable lipid production is then fundamental to address these problems. Oleaginous yeasts are a promising solution for sustainable lipid production, but, with the current knowledge and technology, they are still not a serious alternative in the market. In this review, the potential of these yeasts is highlighted and a discussion is made mainly focused on the economics of the oleaginous yeast oil production and identification of the key points to be improved to achieve lower production costs and higher income. Three main stages of the production process, where costs are higher, were identified. To render economically feasible the production of oils using oleaginous yeasts, a reduction in production costs must occur in all stages, lipid yields and productivities must be improved, and production must be targeted to high-value product applications.

In vitro-to-in vivo extrapolation (IVIVE) by PBTK modeling for animal-free risk assessment approaches of potential endocrine-disrupting compounds.

While in vitro testing is used to identify hazards of chemicals, nominal in vitro assay concentrations may misrepresent potential in vivo effects and do not provide dose-response data which can be used for a risk assessment. We used reverse dosimetry to compare in vitro effect concentrations-to-in vivo doses causing toxic effects related to endocrine disruption. Ten compounds (acetaminophen, bisphenol A, caffeine, 17α-ethinylestradiol, fenarimol, flutamide, genistein, ketoconazole, methyltestosterone, and trenbolone) have been tested in the yeast estrogen screening (YES) or yeast androgen-screening (YAS) assays for estrogen and androgen receptor binding, as well as the H295R assay (OECD test guideline no. 456) for potential interaction with steroidogenesis. With the assumption of comparable concentration-response ratios of these effects in the applied in vitro systems and the in vivo environment, the lowest observed effect concentrations from these assays were extrapolated to oral doses (LOELs) by reverse dosimetry. For extrapolation, an eight-compartment Physiologically Based Toxicokinetic (PBTK) rat model based on in vitro and in silico input data was used. The predicted LOEL was then compared to the LOEL actually observed in corresponding in vivo studies (YES/YAS assay versus uterotrophic or Hershberger assay and steroidogenesis assay versus pubertal assay or generation studies). This evaluation resulted in 6 out of 10 compounds for which the predicted LOELs were in the same order of magnitude as the actual in vivo LOELs. For four compounds, the predicted LOELs differed by more than tenfold from the actual in vivo LOELs. In conclusion, these data demonstrate the applicability of reverse dosimetry using a simple PBTK model to serve in vitro-in silico-based risk assessment, but also identified cases and test substance were the applied methods are insufficient.

Microbial cell factories for the sustainable manufacturing of B vitamins.

Vitamins are essential compounds in human and animal diets. Their demand is increasing globally in food, feed, cosmetics, chemical and pharmaceutical industries. Most current production methods are unsustainable because they use non-renewable sources and often generate hazardous waste. Many microorganisms produce vitamins naturally, but their corresponding metabolic pathways are tightly regulated since vitamins are needed only in catalytic amounts. Metabolic engineering is accelerating the development of microbial cell factories for vitamins that could compete with chemical methods that have been optimized over decades, but scientific hurdles remain. Additional technological and regulatory issues need to be overcome for innovative bioprocesses to reach the market. Here, we review the current state of development and challenges for fermentative processes for the B vitamin group.

Production of D-lactic acid by Lactobacillus delbrueckii ssp. delbrueckii from orange peel waste: techno-economical assessment of nitrogen sources.

In this study, the effect of several organic nitrogen sources (namely peptone, meat extract-ME, yeast extract-YE, and corn steep liquor-CSL) on D-lactic acid production by Lactobacillus delbrueckii ssp. delbrueckii has been studied. While lactic acid bacteria (LAB) are well-known for their complex nutritional requirements, organic nitrogen source-related cost can be as high as 38% of total operational costs (OPEX), being its nature and concentration critical factors in the growth and productivity of the selected strain. Corn steep liquor (CSL) has been chosen for its adequacy, on the grounds of the D-lactic acid yield, productivity, and its cost per kilogram of product. Finally, orange peel waste hydrolysate supplemented with 37 g/l CSL has been employed for D-lactic acid production, reaching a final yield of 88% and a productivity of 2.35 g/l h. CSL cost has been estimated at 90.78$/ton of D-lactate.

Measurements of the optical coefficients of the protoporphyrin IX endogenously producing yeast-based model in the visible and NIR.

Models mimicking the endogenous production of protoporphyrin IX (PpIX), as well as its fluorescence, are of high interest for applied and fundamental studies in the fields of cancer detection by fluorescence imaging, photodynamic therapy (PDT), and photobiomodulation (PBM). Here, we present and describe optical properties of the yeast-based models able to produce PpIX endogenously after the administration of 5-aminolevulinic acid (ALA) and/or 2,2'-bipyridyl. As their optical properties have an important impact on the spatial distribution of the fluence rate in these liquid models, their absorption and reduced scattering coefficients were determined to be between 400 and 808 nm for two yeast solutions previously described by our group. These coefficients were derived from measurements of the total reflectance and light penetration depth using a dedicated Monte Carlo simulation. We observed that absorption and scattering coefficients were smaller than those of soft tissues at all wavelengths. This work will enable the production of a low-cost optical phantom loaded with appropriate amounts of light-absorbing and -scattering particles to mimic tumors containing PpIX, offering a useful tool to optimize the spectral and radiometric design of certain cancer photodetection setups.

Recent advances in microbial production of mannitol: utilization of low-cost substrates, strain development and regulation strategies.

Mannitol has been widely used in fine chemicals, pharmaceutical industries, as well as functional foods due to its excellent characteristics, such as antioxidant protecting, regulation of osmotic pressure and non-metabolizable feature. Mannitol can be naturally produced by microorganisms. Compared with chemical manufacturing, microbial production of mannitol provides high yield and convenience in products separation; however the fermentative process has not been widely adopted yet. A major obstacle to microbial production of mannitol under industrial-scale lies in the low economical efficiency, owing to the high cost of fermentation medium, leakage of fructose, low mannitol productivity. In this review, recent advances in improving the economical efficiency of microbial production of mannitol were reviewed, including utilization of low-cost substrates, strain development for high mannitol yield and process regulation strategies for high productivity.

Safety Assessment and Comparison of Sodium Selenite and Bioselenium Obtained from Yeast in Mice.

Detailed safety assessment of sodium selenite and bioselenium (bio-Se) was conducted and the results were compared and discussed for the purpose of assessing safety of bio-Se for use in food applications. In this work, acute toxicity studies, micronucleus test, and sperm aberration study in mice, 30-day feeding test of mice, were conducted to evaluate the toxicity of bio-Se obtained from yeast with different fermentation time (transformative time: one month, three months, and six months), and the results were compared with that of inorganic Se (sodium selenite). LD50 of sodium selenite was calculated to be 21.17 mg/kg. LD50 of bio-Se obtained from yeast with different fermentation time was calculated to be 740.2 mg/kg, 915.3 mg/kg, and 1179.0 mg/kg, respectively. In the genotoxicity test, bio-Se did not show cytotoxicity and genotoxicity of mice while sodium selenite at all dose groups was significantly different from the negative group. In the 30-day subchronic oral toxicity study, sodium selenite may slow down the growth of the mice and lead to organic damage to some extent. Bio-Se had facilitated effect towards the body weight of the mice and had no significant effect on the shape and function of the important organs of the mice.

Utility of Acridine Orange staining for detection of bacteria from positive blood cultures.

The diagnostic performance of AO stain was evaluated for the detection of bacteria and or fungi from positive blood cultures. The sensitivity of Gram stain (GS) was 98.26% while Acridine Orange (AO) stain proved to be more sensitive (100%) with a Positive and Negative Predictive Value of 100% each. The specificity of both the stains was 100%. Overall agreement between the two stains was 98.23% (688/700). The organisms that were missed by GS and positive by AO were Candida species (Sutton, 2006) and Gram negative bacilli (GNB) (Sutton, 2006). Sensitivity of GS was 82.35% and AO was 100% among mixed cultures. Immediate reporting of the results of AO stain would have a significant impact on clinical management of patients with serious blood stream infections.

Yeast derived from lignocellulosic biomass as a sustainable feed resource for use in aquaculture.

The global expansion in aquaculture production implies an emerging need of suitable and sustainable protein sources. Currently, the fish feed industry is dependent on high-quality protein sources of marine and plant origin. Yeast derived from processing of low-value and non-food lignocellulosic biomass is a potential sustainable source of protein in fish diets. Following enzymatic hydrolysis, the hexose and pentose sugars of lignocellulosic substrates and supplementary nutrients can be converted into protein-rich yeast biomass by fermentation. Studies have shown that yeasts such as Saccharomyces cerevisiae, Candida utilis and Kluyveromyces marxianus have favourable amino acid composition and excellent properties as protein sources in diets for fish, including carnivorous species such as Atlantic salmon and rainbow trout. Suitable downstream processing of the biomass to disrupt cell walls is required to secure high nutrient digestibility. A number of studies have shown various immunological and health benefits from feeding fish low levels of yeast and yeast-derived cell wall fractions. This review summarises current literature on the potential of yeast from lignocellulosic biomass as an alternative protein source for the aquaculture industry. It is concluded that further research and development within yeast production can be important to secure the future sustainability and economic viability of intensive aquaculture. © 2016 Society of Chemical Industry.

Assessment of table olive fermentation by functional data analysis.

For the first time, functional data analysis (FDA) was used to assess the effects of different treatments on Protection Denomination of Origin Aloreña de Málaga table olive fermentations, focusing on the evolution of yeast population. The analysis of fermentation by a conventional approach led to scarce information. However, the transformation of microbial (and also physicochemical) data into smooth curves allowed the application of a new battery of statistical tools for the analysis of fermentations (functional pointwise estimation of the averages and standard deviations, maximum, minimum, first and second derivatives, functional regression, and functional F and t-tests). FDA showed that all the treatments assayed led to similar trends in yeast population while changes in pH and titratable acidity profiles led to several significant differences. Therefore, FDA represents a promising and valuable tool for studying table olive fermentations and for food microbiology in general.