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The potential of 89 culturable cold-adapted isolates from uncontaminated habitats, including 61 bacterial and 28 yeast strains, to utilize representative fractions of petroleum hydrocarbons (n-alkanes, monoaromatic and polycyclic aromatic hydrocarbons) for growth and to produce various enzymes at 10 degrees C was investigated. The efficiency of bacterial and yeast strains was compared. The growth temperature range of the yeast strains was significantly smaller than that of the bacterial strains. Sixty percent of the yeasts but only 8% of the bacteria could be classified as true psychrophiles, showing no growth above 20 degrees C. A high percentage (89%) of the yeast strains showed lipase activity. More than one-third of the 61 bacterial strains produced amylase, beta-lactamase, beta-galactosidase or lipase; more than two-thirds were protease producers. Only 6% of the bacterial strains but 79% of the yeast strains utilized n-hexadecane for growth; 13% of the bacterial strains and 21-32% of the yeast strains utilized phenol, phenanthrene or anthracene for growth. Only four yeast strains but none of the bacterial strains could grow with all hydrocarbons tested. The biodegradation of phenol was investigated in fed-batch cultures at 10 degrees C. Three yeast strains degraded phenol concentrations as high as 10 mM (one strain) or 12.5 mM (two strains). Of eight bacterial strains, two strains degraded up to 10 mM phenol. The optimum temperature for phenol degradation was 20 degrees C for all eight bacterial strains and for two yeast strains. Biodegradation by five yeast strains was optimal at 10 degrees C and faster at 1 degrees C than at 20 degrees C. All phenol-degrading strains produced catechol 1,2 dioxygenase activity.

The impact of yeast and lactic acid bacteria strains on the fruity aroma of red wines was investigated by sensory and analytical strategies. The ester composition of four different Bordeaux red wines was quantified by HS-SPME-GC/MS. These wines, made with selected yeast and bacteria strains, were investigated at the end of alcoholic fermentation and regularly until 12 months of aging, during 2011 and 2012 vintages. Sensory analyses of wines after 3 and 12 months of aging revealed significant differences with regard to yeast strains. Bacteria seemed to have only a slight impact on changes in aromatic profile. Ester levels were strongly influenced by yeast strain and very little affected by malolactic fermentation and aging. Differences and similarities between sensory data and ester profile are discussed. This study highlights the importance of yeast strains in red winemaking. Their sensory impact remains despite the other vinification steps after alcoholic fermentation.

The aim of this research was to investigate the bioremediation conditions of copper in synthetic water. In the present study, copper ions accumulation efficiency was determined using various genetically modified strains of Saccharomyces cerevisiae (EBY100, INVSc1, BJ5465, and GRF18), Pichia pastoris (X-33, KM71H), Escherichia coli (XL10 Gold, DH5α, and six types of BL21 (DE3)), and Escherichia coli BL21 (DE3) OverExpress expressing two different peroxidases. Viability tests of yeast and bacterial strains showed that bacteria are viable at copper concentrations up to 2.5 mM and yeasts up to 10 mM. Optical emission spectrometry with inductively coupled plasma analysis showed that the tolerance of bacterial strains on media containing 1 mM copper was lower than the tolerance of yeast strains at the same copper concentration. The E. coli BL21 RIL strain had the best copper accumulation efficiency (4.79 mg/L of culture normalized at an optical density of 1.00), which was 1250 times more efficient than the control strain. The yeast strain S. cerevisiae BJ5465 was the most efficient in copper accumulation out of a total of six yeast strains used, accumulating over 400 times more than the negative control strain. In addition, E. coli cells that internally expressed recombinant peroxidase from Thermobifida fusca were able to accumulate 400-fold more copper than cells that produced periplasmic recombinant peroxidases.

Piyanun Harnpicharnchai , Janthima Jaresitthikunchai , Mintra Seesang , Sasitorn Jindamorakot , Sutipa Tanapongpipat and Supawadee Ingsriswang . Microbiol. Biotechnol. Lett. 2020;48:138-47. https://doi.org/10.4014/mbl.1910.10008

Considering the great biodiversity of the still unexploited Brazilian environment, efforts were made to select microorganisms capable of producing fructooligosaccharide (FOS). Amongst 495 interesting isolated yeast strains, one in particular, identified as a Rhodotorula red yeast strain isolated from flowers from the Brazilian tropical biomass, was able to produce an effective thermostable extracellular enzyme, with both sucrose hydrolytic and transfructosylating activities. The best operational conditions for this enzyme were determined to be in a pH range from 3.8 to 4.3 and at temperatures of around 65C. Under these conditions, the transfructosylating activity reached its maximum, being more than 10 times higher than the hydrolytic activity. The synthesis of fructooligosaccharides from sucrose resulted in total conversion of the substrate into FOS (48%), glucose (31.3%) and fructose (20.7%). In addition, it was shown that the synthesized FOS had a prebiotic effect, promoting the growth of probiotic bacteria. PRACTICAL APPLICATIONS The search for new enzymes for oligosaccharide production, using either microbial screening or molecular engineering, became necessary as a result of the increasing number of applications of these carbohydrates in the cosmetic, agrochemical, pharmaceutical and food industries. In this work, the Rhodotorula sp. isolated from Brazilian biomes was shown to be capable of producing an extracellular fructosyltransferase enzyme with good prospects for further studies aiming an industrial application, because it can convert sucrose into fructooligosaccharide (FOS), giving high yields (50%). It is worthwhile to emphasize the high optimum temperature and low pH value of the enzyme operation, which make it possible to work in a nonsterile environment for FOS production. It is also remarkable the ability of this yeast type (Rhodotorula), of growing on diverse alternative media and agricultural by-products (molasses, corn steel liquor, grape must, whey ultrafiltrate).

Fiber sources differ in a number of physicochemical properties, and certain combinations may yield more desirable physiological effects. Potential benefits include normalized bowel function, increased short chain fatty acid (SCFA) production and beneficial changes in gut microbiota. Negative side effects may include excess gas production leading to intolerance. We hypothesized that a 50:50 blend of fermentable and nonfermentable fibers (Blend 1) would attenuate gas production while achieving benefits similar to more fermentable blends. The fermentation profiles of Blend 1 (fructooligosaccharide (FOS), inulin, acacia gum (AG), and outer pea fiber), Blend 2 (short chain FOS, carboxymethylcellulose, AG, oat hull and soy fiber), and Blend 3 (soy polysaccharide, cellulose, AG, inulin, oligofructose, and resistant starch) were examined using an in vitro batch fermentation model. Triplicate samples were removed at 4, 8, 12, and 24 h for analysis of gas, pH and SCFAs. Blend 1 produced significantly less gas than Blend 2 and Blend 3 (p<0.05), and had higher pH values (p<0.05). Production of total and individual SCFAs was similar among blends. In conclusion, fermentation of Blend 1 resulted in less gas while achieving similar SCFA production as other blends. These results may help predict health benefits and tolerance in vivo.Research was supported by Nestlé Health Science.

Short‐chain fructooligosaccharides (FOS) are a long‐studied functional food made up of a glucose molecule linked to between 2 and 4 fructose molecules and not significantly digested in the small intestine. Short‐chain FOS provide an energy source that is relatively specific for beneficial bacteria in the large intestine, with even small amounts leading to dramatic increases in bifidobacteria, which have a variety of health benefits in and of themselves. In addition, a predicable fall in pathogenic bacteria, such as clostridia, occurs as bifidobacteria increase. This has implications for several disorders, ranging from liver disease to antibiotic‐associated diarrhea to colon cancer. Short‐chain FOS are metabolized to short‐chain fatty acids, lowering pH in the colon. This facilitates calcium absorption, which may be beneficial for individuals with renal and liver disease, and has implications for colon cancer protection as well. Short‐chain fatty acids are the preferred substrate for colonic epithelial cells, which are potentially beneficial for those with ulcerative colitis risk. Other effects of short‐chain FOS include an effect on cholesterol metabolism through interference with enterohepatic circulation of cholesterol. Short‐chain FOS allow for a favorable shift in the balance of healthful vs harmful organisms, lowering colonic pH while providing an energy source for the gut, with significant implications for disease prevention.

Coenzyme Q or CoQ is also known as ubiquinone is a benzoquinone that is present in human, animals and most living beings but its isoprene units varies in different living entities ranging from CoQ6 to CoQ10, It is a polyphilic molecule containing hydrophobic isoprenoid chains attached to benzoquinone ring. In humans it is present as CoQ10 containing ten isoprene units, situated in mitochondrial inner membrane and plays an important role in energy generation and free radical scavenging. Due to supportive therapeutic benefits of CoQ10 in humans, it is considered as an industrially important molecule having nutraceutical, pharmaceutical and cosmeceutical applications. Different routes for its synthesis have been tried for commercial production, like chemical and biological, but the later one is preferred. The biological synthesis involves large scale fermentation and extraction of this molecule from CoQ10 containing microbes; hence the process demands the use of microbial strains with high productivity and yields of CoQ10. Studies carried out on the microbial synthesis of CoQ10 over many decades mainly focus on use of bacterial and yeast strains having endogenous biosynthetic pathway for ten isoprene units containing CoQ production. The yields of native CoQ10 have been increased to meet commercial requirements by mutations, fermentation process improvements and metabolic engineering. Attempts have also been made to express the pathway genes in other suitable, non-CoQ10 producing strains to finally synthesize CoQ10. Although, CoQ10 is synthesized using bacterial as well as fungal strains, the fungal source is preferred as CoQ10 biosynthetic pathway of yeast and human is very similar as opposed to bacterial pathways. The CoQ10 from a eukaryote has more similarity in terms of functionality with human CoQ10 and high degree of conservation with a mammalian species. Therefore, commercial production of CoQ10 using fungi/yeast is most preferred and highlights its importance. This review explains the properties, functions of CoQ10, its biosynthesis from the wild as well as recombinant strains and the physiological significance of CoQ10 in human wellbeing.

Dear Editor, In their recent article Kelishadi et al. (1) analyzed in a clear and concise way a number of key aspects of obesity-related NAFLD, deepening in particular the role of gut microflora and its potential therapeutic modulation by probiotics. From their paper it is apparent that most promises still derive from a relevant number of studies conducted in different NAFLD animal models. When interpreting data obtained in these models one should however remind that other factors like physical activity, social and chemical environment, psychological stress factors and genetics are also important contributors to the development of human NAFLD and to its incredible resistance to treatments as well (2). In this respect Dr. Kelishadi and colleagues' review of four available clinical trials on human population is therefore particularly welcomed. In three studies probiotic treatments appear to improve somehow NAFLD related parameters. The fourth study, published in 2008 by doctor Diehl’s group, instead warned versus probiotics treatment of NAFLD, reporting that steatosis measured by proton magnetic resonance spectroscopy increased in three out of four patients treated with VSL#3 for 4 months (3). In addition to these meagre evidences, in recent times, Malguarnera et al. showed in histologically monitored NAFLD patients that Bifidobacterium longum + fructo-oligosaccharides (FOS) treatment and lifestyle modification, when compared to lifestyle modification alone, significantly reduced a number of serum inflammatory, metabolic, toxinic and cytolitic parameters, along with improved histological steatosis, and NASH activity index (4). Even more recently, a further open label randomized controlled trial in 20 obese adult patients with biopsy proven NAFLD appeared fairly promising. Patients received a six month formula containing five strains of bacteria (4 lactobacilli + Bifidobacterium bifidum) + FOS. Treatment resulted in reduction of liver fat (P = 0.034) and AST level (absolute change P = 0.021; percentage of baseline value P = 0.008) (5). In all cases, it should be emphasized that the hitherto available study designs are not homogeneous and data results cannot be easily compared. Study population of two examined series by dr Kelishadi and colleagues for example included different chronic liver diseases in addition to NAFLD (6, 7); probiotics preparations often contained different bacteria strains, and sometimes confounding prebiotics (FOS) and/or vitamins cocktails (4-6); study duration was quite different, and it is still not clear if longer study may be affected by a number of biases like concurrent unpredictable major life style modifications, and at which extent. Last, but not least, although the Authors reminded the seriousness of epidemiologic data of pediatric NAFLD, they do not refer further to pediatric therapeutic studies targeting gut microbiota. In this regard we think therefore it might be valuable to the discussion completeness also the inclusion of our 2011 study published in Journal of Pediatric Gastroenterology and Nutrition (8). In that double-blind, placebo-controlled pilot study the effects of a short-term (8 weeks) probiotic treatment in 20 children with obesity-related liver disease were evaluated. Patients received Lactobacillus Rhamnosus strain GG (12 billion CFU/day): this probiotic strain was chosen because of the proven safety and efficacy profile in previous pediatric studies. Consistently with available adult data, in our population a multivariate analysis after probiotic treatment revealed a significant decrease in alanine aminotransferase (average variation vs. placebo P = 0.03), with normalization in most (80%) cases, irrespective of changes in BMI z score and visceral fat. We measured anti peptidoglycan-polysaccharide (PGPS) antibodies, an indirect indicator of intestinal bacterial overgrowth. PGPS is a ubiquitous bacterial antigen found in both gram-positive and gram-negative bacteria wall, and anti PGPS production is a sign of bacteria or bacterial membrane translocation through intestine barrier. Interestingly PGPS antibodies were significantly reduced after probiotic treatment (average variation vs. placebo P = 0.03). Serum levels of tumor necrosis factor-alpha, and US bright liver parameters remained stable during the study frame. Summing up, taking into account also the above additional evidences, we agree with Dr. Kelishadi and colleagues that available animal and human studies altogether may authorize to further support the view of a reasonable therapeutic role of probiotics in adult and also pediatric NAFLD patients not compliant to lifestyle changes, also because of minimal adverse effects and low cost (9). For better clarifying these aspects, future studies still need to be planned on well characterized larger populations, possibly with single probiotic agents, followed by a wash out period, and/or with gut microbiota characterization. The latter, much interestingly, has been defined only very recently both in adult (10)and in pediatric NAFLD (11).

The present study is aimed with an objective to produce bio ethanol from agrowaste. Paddy straw bio mass is collected from agricultural land and utilized as feed stock for ethanol production after subjecting them to acid, alkali and enzymatic pre treatments. Two bacterial strains (R2 and R3) and one yeast strain (S6) were isolated from soil samples collected from paddy field dumped with straw and from sugarcane bagasse dumped soil. In addition to this, cellulose degrading bacteria strain (C1) is isolated to carry out the enzymatic pre treatment. Based on the fermentation efficiency tested, S6, R2 and R3 strains were inoculated in eight different pretreated biomass filtrate medium for fermentation process. Ethanol concentration were quantified at a period of five days interval up to twenty days. Ethanol concentration increased from 5th day to 20th day and 5th day to 15th day in yeast and bacteria inoculated medium. After recovery through distillation, yeast strain S6 inoculated medium is reported with more concentration of ethanol in alkali pre treated bio mass filtrate medium. There is no significant difference between alkali pre treated biomass and combined alkali & enzyme pre treated bio mass inoculated with yeast strain at 0.001 level of significance. The overall product extracted is in the range of 5-12%. Ethanol extracted from yeast S6 is reported to have disinfectant effect against bacteria. FTIR spectrum analysis reported the presence of similar peaks to that of standard ethanol

In this study, the antimicrobial, antioxidant and antitumor activity of ethanol extracts obtained from Phlomis russeliana (Sims.) Lag. ex Benth. (Lamiaceae) were evaluated. Disc diffusion and microdilution methods were used to test the extracts for antimicrobial activity against seven bacteria strains (Bacillus cereusATCC 7064, Bacillus subtilisATCC 6633, Staphylococcus aureusATCC 6538P, Escherichia coliATCC 10538, Proteus vulgarisATCC 6899, Salmonella typhimuriumCCM 5445 and Pseudomonas aeruginosaATCC 27853) and four yeast strains (Kluyveromyces fragilisATCC 8608, Rhodotorula rubraATCC 70403, Debaryomyces hanseniiDSM 70238 and Candida albicansATCC 10239). Notably, they were more effective against the yeast strains than the bacterial strains. Of the yeast cultures, D. hanseii was among the most susceptible, having an inhibition zone of 16.2 mm with minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of 64(128)µg/ml, respectively. For cytotoxic determination, Caco-2 cells were cultured as per ATCC protocol, and were treated with log concentrations (5-80 mg/ml) of P. russeliana. The potency of cell growth inhibition for each extract was expressed as an IC50 value. Moreover, oxidant capacity was evaluated via TOC assay. This product induced antiproliferative activity of 31.33% at 40 mg/ml and 20.96% at 80 mg/ml, without toxic effects on cells, although the oxidant capacity was decreased to 27.06 ± 0.7 nm in the 80 mg/ml-applied group compared to 47.9 ± 1.8 nm in the untreated one. Advanced pharmacological studies are needed to further evaluate P. russeliana for distinctive features.

Fructooligosaccharides (FOS) are usually added in milk powder as a kind of prebiotic. Thus, quantitative analysis of the FOS is very important for the quality control of milk powder. In this study, a simple method for the simultaneous determination of three FOS components with degrees of polymerization (DP) 3-5 in milk powder was developed by high performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD). The samples were extracted with 50% (v/v) ethanol aqueous solution and defatted by an On Guard RP pretreatment column. The separation was performed on a CarboPac PA200 column by gradient elution using deionized water, 0. 2 mol/L NaOH solution and 0. 4 mol/L NaAc solution as the mobile phases. The flow rate was 0. 4 mL/min. The column temperature was 30 °C; and the injection volume was 25 µL. Good linear response was observed in the concentration range of 0.05-10 mg/L (r2 >0. 9993). The limits of quantification were 0. 02, 0. 005 and 0. 02 mg/L for 1-kestose, nystose and fructofuranosyl-nystose, respectively. The mean recoveries varied from 86. 0% to 114. 0% at three spiked levels of 0. 5, 1. 0 and 5. 0 mg/L. The short-chain fructooligosaccharides from inulooligosaccharides (IOS) were successfully separated by the developed HPAEC-PAD method. The method is simple, accurate, sensitive, and helpful for the quality control of milk powder.

Short-chain fructo-oligosaccharides improve magnesium absorption in adolescent girls with a low calcium intake

Fructan fatty acid esters are amphiphilic compounds with potential applications in the food industry due to their surface-active properties on the air/water interface. In this work, the regioselective synthesis of fatty acid esters of short-chain inulin-type fructooligosaccharides (FOS) was carried out in a two-step process comprising sequential enzymatic reactions of transfructosylation and acylation. In the first step, Schedonorus arundinaceus sucrose:sucrose 1-fructosyltransferase (1-SST, EC 2.4.1.99) converted sucrose (600 g/L) into the trisaccharide 1-kestose and the tetrasaccharide nystose in a ratio 9:1 with their sum accounting for 53% (w/w) of total carbohydrates. In the second step, the FOS mixture was transesterified with vinyl laurate in 2-methyl-2-butanol by immobilized Candida antarctica lipase B (CALB) (EC.3.1.1.3). NMR analysis of the synthesized monolaurate FOS esters revealed a regioselective acylation of the 6-OH of the terminal fructosyl moiety of both 1-kestose and nystose. The hydrophilic-lipophilic balance (HLB) values of 6’’-O-lauroyl-1-kestose and 6’’’-O-lauroylnystose were 14.7 and 15.7, respectively; which suggests their use as oil in water (O/W) emulsifiers. The main compound 6’’-O-lauroyl-1-kestose with critical micelle concentration (CMC) of 0.6 mM and surface tension of 45.8 mN/m proved to be a more efficient surfactant than 6’’’-O-lauroylnystose (CMC 5.38 mM) and surface tension 36.26 mN/m). We report a regioselective method for the synthesis of lauryl-FOS using the abundant and renewable resource sucrose as the starting substrate.

Inflammatory bowel disease, a dysregulated host‐microbiota interaction: Are probiotics a new therapeutic option?