Biomethane production and microbial strategies corresponding to high organic loading treatment for molasses wastewater in an upflow anaerobic filter reactor.

Molasses wastewater contains high levels of organic compounds, cations, and anions, causing operational problems for anaerobic biological treatment. In this study, an upflow anaerobic filter (UAF) reactor was employed to establish a high organic loading treatment system for molasses wastewater and further investigated the microbial community dynamics in response to this stressful operation. The biogas production increased with an increase in total organic carbon (TOC) loading rate from 1.0 to 14 g/L/day, and then it decreased with further TOC loading rate addition until 16 g/L/day. The UAF reactor achieved a maximum biogas production of 6800 mL/L/day with a TOC removal efficiency of 66.5% at a TOC loading rate of 14 g/L/day. Further microbial analyses revealed that both the bacterial and archaeal communities developed multiple strategies to maintain stable operation of the reactor at high organic loading (e.g., Proteiniphilum and Defluviitoga maintained high abundances throughout the operation; Tissierella temporarily dominated the bacterial community at TOC loading rates of 8.0 to 14 g/L/day; and multi-trophic Methanosarcina shifted as the dominant methanogen at the TOC loading rates of 8.0 to 16 g/L/day). This study presents insights into a high organic loading molasses wastewater treatment system and the microbial flexibility in methane fermentation in response to process disturbances.

Insight into the pilot-scale fed-batch fermentation for production of Enterococcus faecium CW3801 using molasses-based medium.

Enterococcus sp. has been used as starters in food fermentation due to their probiotic and antimicrobial properties in food biopreservation. The antimicrobial properties were mainly contributed by the bacteriocin called enterocin. Hence, the availability of a cost-effective pilot-scale cultivation conditions is a necessity for the production of probiotic bacteria. This study aims to investigate optimization of medium composition using sugarcane molasses as a carbon source using response surface methodology and the potential use of fed-batch cultivation for improvement of the cell viability of Enterococcus faecium CW3801 for the use as a probiotic starter culture. Two feeding strategies (ramp and constant) were applied in fed-batch cultivation for enhancement of the production of E. faecium in a 2-L stirred tank bioreactor using the optimized medium and scaled up to a 15-L bioreactor. Optimized fermentation medium which comprised of 10% (v/v) of molasses and 10 g/L of yeast extract at pH 7 yielded maximum cell viability of 29.4 × 1011 CFU/mL with 3900 AU/mL of bacteriocin-like inhibitory substances (BLIS) activity. In the fed-batch, the cell viability (8.4 × 1013) and dry cell weight (6.34 g/L) reached the highest in optimized medium when the ramp (stepwise) feeding was applied. In scaling up to 15-L bioreactor, the growth of E. faecium was achieved at 2.3 × 1013 CFU/mL with the dry cell weight of 5.28 g/L under the same condition. The BLIS in 15-L bioreactor was 6% higher than the 2-L bioreactor. This study demonstrated that molasses and yeast extract are good feedstock for the growth of E. faecium. The E. faecium, a non-vancomycin resistant enterococcus (VRE) was successfully produced by a fed-batch cultivation approach and scaled up to a 15-L bioreactor using a ramp feeding strategy. Results from this study revealed that the fed-batch cultivation using molasses-based medium has industrial potential for the production of probiotics.

Effect of sugarcane bagasse as industrial by-products treated with Lactobacillus casei TH14, cellulase and molasses on feed utilization, ruminal ecology and milk production of mid-lactating Holstein Friesian cows.

BACKGROUND: The study aimed to evaluate the effect of Lactobacillus casei TH14, cellulase, and molasses combination fermented sugarcane bagasse (SB) as an exclusive roughage source in the total mixed ration (TMR) for mid-lactation 75% crossbred Holstein cows on feed intake, digestibility, ruminal ecology, milk yield and milk composition. Four multiparous mid-lactation crossbred (75% Holstein Friesian and 25% Thai native breed) dairy cows of 439 ± 16 kg body weight, 215 ± 5 days in milk and average milk yield 10 ± 2 kg d-1 were assigned to a 4 × 4 Latin square design. The unfermented SB (SB-TMR), SB fermented with cellulase and molasses (CM-TMR), SB fermented with L. casei TH14 and molasses (LM-TMR), and SB fermented with L. casei TH14, cellulase and molasses (LCM-TMR) were used as dietary treatments. RESULTS: CM-TMR, LM-TMR and LCM-TMR significantly (P < 0.01) increased dry matter and fiber digestibility, gross energy and metabolizable energy intake (P < 0.05), blood glucose, total volatile fatty acids (P < 0.05), propionic acid and milk yield, but decreased ammonia, acetic acid, acetic:propionic ratio and methane production (P < 0.05) when compared with the SB-TMR. Compared with fermented SB treatments, LCM-TMR had lower (P < 0.05) ruminal ammonia and greater blood glucose (P < 0.01); LCM-TMR showed (P < 0.05) greater volatile fatty acids, propionic acid, milk yield and total solids, and lower acetic:propionic ratio (P < 0.01); methane, protozoa and somatic cell count were found to be lowest in LCM-TMR. CONCLUSION: Combination of L. casei TH14 and additives (LCM-TMR) effectively enhanced feed use, rumen ecology and milk production of Holstein Friesian cows. © 2021 Society of Chemical Industry.

Lactobacillus plantarum and molasses alter dynamic chemical composition, microbial community, and aerobic stability of mixed (amaranth and rice straw) silage.

BACKGROUND: The objective was to determine how molasses and Lactobacillus plantarum affect chemical composition, fermentation quality, aerobic stability, and the microbial community of an ensiled mixture of amaranth (Amaranthus hypochondriaus, AF) and rice straw. Treatments were control (C, no addition), L. plantarum (L; 2 × 105 cfu g-1 fresh weight), molasses (M; 40 g kg-1 fresh matter), and their combination (LM). All treatments were ensiled for 1, 3, 5, 7, and 30 days. RESULTS: All additives improved fermentation quality with greater lactic acid (LA), acetic acid, and lower pH than C silage over the ensiling period. The LM silage combination optimized fermentability, manifested as greater LA contents and a more rapid pH reduction during the first 7 days of ensiling than L or M silages. After 30 days of ensiling, inoculant L. plantarum increased Lactobacillus abundance and reduced bacterial diversity and Enterobacteriaceae abundance compared with silage treated with molasses. Molasses addition reduced the relative concentration of structural carbohydrates (neutral and acid detergent fiber, and hemicellulose) after 30 days of ensiling. Finally, there was spoilage after 2 days and 4 days of aerobic exposure in C and LM silages respectively, whereas L silage had not spoiled after 4 days. CONCLUSIONS: Although the combination of L. plantarum and molasses further optimized fermentation characteristics, L silage had better aerobic stability. © 2021 Society of Chemical Industry.

Selection of thermotolerant Saccharomyces cerevisiae for high temperature ethanol production from molasses and increasing ethanol production by strain improvement.

A thermotolerant ethanol fermenting yeast strain is a key requirement for effective ethanol production at high temperature. This work aimed to select a thermotolerant yeast producing a high ethanol concentration from molasses and increasing its ethanol production by mutagenesis. Saccharomyces cerevisiae DMKU 3-S087 was selected from 168 ethanol producing strains because it produced the highest ethanol concentration from molasses at 40 °C. Optimization of molasses broth composition was performed by the response surface method using Box-Behnken design. In molasses broth containing optimal total fermentable sugars (TFS) of 200 g/L and optimal (NH4)2SO4 of 1 g/L, with an initial pH of 5.5 by shaking flask cultivation at 40 °C ethanol, productivity and yield were 58.4 ± 0.24 g/L, 1.39 g/L/h and 0.29 g/g, respectively. Batch fermentation in a 5 L stirred-tank fermenter with 3 L optimized molasses broth adjusted to an initial pH of 5.5 and fermentation controlled at 40 °C and 300 rpm agitation resulted in 72.4 g/L ethanol, 1.21 g/L/h productivity and 0.36 g/g yield at 60 h. Strain DMKU 3-S087 improvement was performed by mutagenesis using ultraviolet radiation and ethyl methane sulfonate (EMS). Six EMS mutants produced higher ethanol (65.2 ± 0.48-73.0 ± 0.54 g/L) in molasses broth containing 200 g/L TFS and 1 g/L (NH4)2SO4 by shake flask fermentation at 37 °C than the wild type (59.8 ± 0.25 g/L). Among these mutants, only mutant S087E100-265 produced higher ethanol (62.5 ± 0.26 g/L) than the wild type (59.5 ± 0.02 g/L) at 40 °C. In addition, mutant S087E100-265 showed better tolerance to high sugar concentration, furfural, hydroxymethylfurfural and acetic acid than the wild type.

Bioprocessing of agro-industrial residues into lactic acid and probiotic enriched livestock feed.

BACKGROUND: Growing challenges of resource depletion, food security and environmental protection are putting stress on the development of biorefinery processes for bioprocessing of residues from food and agro-industry into value-added products. In this study, the simultaneous production of lactic acid (LA) and livestock feed on a combined substrate based on molasses and potato stillage by Lactobacillus paracasei NRRL B-4564 immobilized onto sunflower seed hull (SSH), brewer's spent grain (BSG) and sugar beet pulp (SBP) was studied. RESULTS: The highest total LA concentration of 399 g L-1 with overall productivity of 1.27 g L-1  h-1 was achieved in repeated batch fermentation by SBP-immobilized biocatalyst, followed by BSG- and SSH-immobilized cells. Fermentation improved the content of proteins and ash, and decreased the content of fibers in all three support materials. In addition, the fermentation had favorable effect on in vitro dry matter digestibility and energy values of SSH and BSG. According to assessment of probiotic potential, L. paracasei demonstrated a favorable probiotic profile, exhibiting high resistance to simulated ruminant digestive tract and significant antioxidant and antimicrobial activity. CONCLUSIONS: The proposed strategy enables valorization of agro-industrial residues as value-added ruminant feed and simultaneous LA production. Following principles of circular economy, the developed process combines different raw materials and integrates them into a biorefinery process, improving the overall profitability and productivity. © 2019 Society of Chemical Industry.

Coproduction of hydrogen and methane in a CSTR-IC two-stage anaerobic digestion system from molasses wastewater.

A continuous hydrogen and methane production system in a two-stage process has been investigated to increase energy recovery rate from molasses wastewater in this study. This system consisted of a continuous stirred-tank reactor for hydrogen production and an internal circulation (IC) reactor for methane production, and was studied under the influent organic loading rate (OLR) of 18, 24, 30 and 36kg COD/(m3·d) (COD: chemical oxygen demand). The maximum volumetric hydrogen production rate of 2.41 L/(L·d) was obtained at the OLR of 30kg COD/(m3·d) with a hydrogen content of 42%, and the maximum volumetric methane production rate of 2.4 L/(L·d) with a methane content of 74.45% was obtained at the OLR of 36kg COD/(m3·d) using the effluents of hydrogen fermentation as substrate. The maximum of 71.06% of the molasses wastewater energy was converted to biogas (hydrogen and methane) at the OLR of 30kg COD/(m3·d).

Bioaugmentation with Mixed Hydrogen-Producing Acetogen Cultures Enhances Methane Production in Molasses Wastewater Treatment.

Hydrogen-producing acetogens (HPA) have a transitional role in anaerobic wastewater treatment. Thus, bioaugmentation with HPA cultures can enhance the chemical oxygen demand (COD) removal efficiency and CH4 yield of anaerobic wastewater treatment. Cultures with high degradation capacities for propionic acid and butyric acid were obtained through continuous subculture in enrichment medium and were designated as Z08 and Z12. Bioaugmentation with Z08 and Z12 increased CH4 production by glucose removal to 1.58. Bioaugmentation with Z08 and Z12 increased the COD removal rate in molasses wastewater from 71.60% to 85.84%. The specific H2 and CH4 yields from COD removal increased by factors of 1.54 and 1.63, respectively. Results show that bioaugmentation with HPA-dominated cultures can improve CH4 production from COD removal. Furthermore, hydrogen-producing acetogenesis was identified as the rate-limiting step in anaerobic wastewater treatment.

Modelling of factors influencing the effect of osmotic solution on reduction of selected microorganisms.

AIMS: The goal of this research is to model the effects of two osmotic solutions factors on the reduction of selected microorganisms, and to assess the application in osmotic dehydration process of animal raw materials from the aspect of microbiological safety. METHODS AND RESULTS: Sugar beet molasses and aquatic osmotic solution were prepared and inoculated with Escherichia coli, Listeria monocytogenes and Salmonella spp. Varied factors of osmotic solutions were: time, temperature and concentration of osmotic solutions. Samples of osmotic solutions were subjected to standard and modified microbiological ISO methods. The result showed that increase in factors had a positive effect on the reduction of microbiological load, while the time of the process was the most influential technological parameter. Number of L. monocytogenes was reduced to <10 CFU per g at the end of the process in the highest concentration of sugar beet molasses at all process temperatures. CONCLUSIONS: Developed mathematical models of reduction ratios for tested microorganisms were statistically significant, allowing good prediction of reduction ratio values based on applied factors. SIGNIFICANCE AND IMPACT OF THE STUDY: Obtained levels of reduction of all tested microorganisms present good base for the production of safe osmotically dehydrated products of animal origin.

An integrated bio-process for production of functional biomolecules utilizing raw and by-products from dairy and sugarcane industries.

The study investigated an integrated bioprocessing of raw and by-products from sugarcane and dairy industries for production of non-digestible prebiotic and functional ingredients. The low-priced feedstock, whey, molasses, table sugar, jaggery, etc., were subjected to transglucosylation reactions catalyzed by dextransucrase from Leuconostoc mesenteroides MTCC 10508. HPLC analysis approximated production of about 11-14 g L-1 trisaccharide i.e. 2-α-D-glucopyranosyl-lactose (4-galactosyl-kojibiose) from the feedstock prepared from table sugar, jaggery, cane molasses and liquid whey, containing about 30 g L-1 sucrose and lactose each. The trisaccharide was hydrolysed into the prebiotic disaccharide, kojibiose, by employing recombinant ß-galactosidase from Escherichia coli. The enzyme ß-galactosidase achieved about 90% conversion of 2-α-D-glucopyranosyl-lactose into kojibiose. The D-fructose generated by catalytic reactions of dextransucrase was targeted for catalytic transformation into rare sugar, D-allulose (or D-psicose), by treating the samples with Smt3-D-psicose 3-epimerase. The catalytic reactions resulted in the conversion of ~ 25% D-fructose to D-allulose. These bioactive compounds are known to exert a plethora of benefits to human health, and therefore, are preferred ingredients for making functional foods.

Dual bioremediation of phenol and Cr(VI) by mixed microbial cultures in the presence of molasses.

Simultaneous phenol and Cr(VI) bioremoval by two different mixed cultures, from petroleum-contaminated soil (PS) and boron-contaminated wastewater (BW), was investigated in regard to different culture media, pH levels (6-8), initial phenol (25-100 mg/L) and Cr(VI) (15-50 mg/L) concentrations. The optimum medium was found to be mineral salt medium tested, which contained 1% (v/v) molasses (MSM). Optimum pH values were 6 for PS and 8 for BW. All of the phenol present in the samples was mineralized regardless of its concentrations tested, Cr(VI) bioremoval was enhanced by the increase in phenol concentrations, and molasses also exerted a positive effect on Cr(VI) removal, and the yields reached 100% for both pollutants, even at 13.1 mg/L Cr(VI) and 91.1 mg/L phenol concentration in PS samples. In MSM containing PS samples approximate efficiency was 100% for phenol removal; but Cr(VI) removal ratios were 64.9% and 41.7% at 25.8 mg/L and 41.3 mg/L concentrations, respectively. Finally it can be concluded that molasses stimulated Cr(VI) bioremoval at elevated phenolic conditions in the mixed microbial culture, and molasses might be of use for the bioremediation of phenol and Cr(VI) polluted wastewaters.

Hyper-production of levansucrase from Zymomonas mobilis KIBGEIB14 using submerged fermentation technique.

The industrial utilization of enzymes requires the high yield of enzyme production for the synthesis of polymers by microorganisms. Therefore, it is necessary to optimize different production parameters of levansucrase in order to increase its industrial applications. Zymomonas mobilis KIBGE-IB14 was considered as a promising candidate for the large scale production of levan among wide range of microorganisms. The current investigation is aimed to optimize the production parameters of levansucrase by Z. mobilis KIBGE-IB14 isolated from molasses. The results indicated that bacterial growth as well as enzyme production was greatly influenced by both physical and chemical conditions. It was revealed that high enzyme titers were achieved at 30°C with pH 6.5 after 24 hours of incubation in a modified medium. Moreover, the enzyme exhibited its induction in the presence of sucrose used as a substrate. Thus, the present study demonstrated that newly isolated Z. mobilis KIBGE-IB14 can be used as a plausible producer of levansucrase for industrial applications.

Biomethane production and microbial community response according to influent concentration of molasses wastewater in a UASB reactor.

This study aimed to investigate the interaction between methane production performance and active microbial community dynamics at different loading rates by increasing influent substrate concentration. The model system was an upflow anaerobic sludge blanket (UASB) reactor using molasses wastewater. The active microbial community was analyzed using a ribosomal RNA-based approach in order to reflect active members in the UASB system. The methane production rate (MPR) increased with an increase in organic loading rate (OLR) from 3.6 to 5.5 g COD·L(-1)·day(-1) and then it decreased with further OLR addition until 9.7 g COD·L(-1)·day(-1). The UASB reactor achieved a maximum methane production rate of 0.48 L·L(-1)·day(-1) with a chemical oxygen demand (COD) removal efficiency of 91.2 % at an influent molasses concentration of 16 g COD·L(-1) (OLR of 5.5 g COD·L(-1)·day(-1)). In the archaeal community, Methanosarcina was predominant irrespective of loading rate, and the relative abundance of Methanosaeta increased with loading rate. In the bacterial community, Firmicutes and Eubacteriaceae were relatively abundant in the loading conditions tested. The network analysis between operation parameters and microbial community indicated that MPR was positively associated with most methanogenic archaea, including the relatively abundant Methanosarcina and Methanosaeta, except Methanofollis. The most abundant Methanosarcina was negatively associated with Bifidobacterium and Methanosaeta, whereas Methanosaeta was positively associated with Bifidobacterium.

Enrichment of Methanosaetaceae on carbon felt and biochar during anaerobic digestion of a potassium-rich molasses stream.

Biorefineries allow the production of value-added chemicals, yet this also causes the formation of considerable amounts of wastewater that require suitable treatment. These biorefinery wastewaters often contain a high salinity, which inhibits methanogenesis. In this research, molasses were used to mimic these waste streams to evaluate their treatability by anaerobic digestion. Two different carrier materials, i.e., carbon felt and biochar, with similar surface properties were evaluated for their potential to stabilize anaerobic digestion of these wastewaters via active enrichment of the methanogenic community. Initial stable methane production values between 620 and 640 mL CH4 L(-1) day(-1) were reported in each treatment. At the end of the experiment, methane production decreased with more than 50 %, while VFA increased to values up to 20 g COD L(-1), indicating severe process failure, due to the high potassium concentration in these wastewaters, irrespective of the presence of carrier material. However, an increased relative abundance of Methanosaetaceae both on the biochar and carbon felt was observed. In conclusion, this research demonstrated that carbon felt and biochar are both suitable carrier materials for selective enrichment of Methanosaetaceae, yet this did not lead to stable anaerobic digestion of a potassium-rich molasses waste stream. The increased relative abundance of Methanosaetaceae on both carrier materials can, nonetheless, be considered valuable in terms of alternative applications and warrants further research.

Removal of pigments from molasses wastewater by combining micro-electrolysis with biological treatment method.

Pigments in molasses wastewater (MWW) effluent, such as melanoidins, were considered as kinds of the most recalcitrant and hazardous colorant contaminants to the environment. In this study, de-coloring the MWW by a synergistic combination of micro-electrolysis with bio-treatment was performed. Aiming to a high de-colorization yield, levels of nutrition source supplies, MWW dilution ratio, and micro-electrolysis reaction time were optimized accordingly. For a diluted (50 %, v/v) MWW, an maximum overall de-colorization yield (97.1 ± 0.5 %, for absorbance at 475 nm) was achieved through the bio-electrolysis treatment. In electrolysis bio-treatment, the positive effect of micro-electrolysis was also revealed by a promoted growth of fungal biomass as well as activities of ligninolytic enzymes. Activities of lignin peroxidase, manganese peroxidase, and laccase were promoted by 111.2, 103.9, and 7.7 %, respectively. This study also implied that the bio-treatment and the micro-electrolysis had different efficiencies on removal of pigments with distinct polarities.

Single cell oil production on molasses by Yarrowia lipolytica strains overexpressing DGA2 in multicopy.

Yarrowia lipolytica is a promising platform for single cell oil production. It is well-known for its metabolism oriented toward utilization of hydrophobic substrates and accumulation of storage lipids. Multiple copies of DGA2 under constitutive promoter were introduced into the Q4 strain, a quadruple mutant deleted for the four acyltransferases (Δdga1, Δdga2, Δlro1, and Δare1) to improve lipid accumulation. The Q4-DGA2 x3 strain contains three copies of DGA2. Further increase in accumulation was accomplished by blocking the ß-oxidation pathway through MFE1 gene deletion yielding Q4-Δmfe DGA2 x3. In order to use molasses as a substrate for single cell oil production, sucrose utilization was established by expressing the Saccharomyces cerevisiae SUC2 gene yielding Q4-SUC2 DGA2 x3 and Q4-Δmfe SUC2 DGA2 x3. During cultivation on sucrose medium with a carbon to nitrogen ratio of 80, both strains accumulated more than 40 % of lipids, which was a 2-fold increase in lipid storage. Q4-Δmfe SUC2 DGA2 x3 accumulated more lipids than Q4-SUC2 DGA2 x3 (49 vs. 43 %) but yielded less biomass (13.7 vs. 15 g/L). When grown on 8 % (v/v) molasses, both strains accumulated more than 30 % of lipids after 3 days, while biomass yield was higher in Q4-SUC2 DGA2 x3 (16.4 vs. 14.4 g/L). Further addition of molasses at 72 h resulted in higher biomass yield, 26.6 g/L for Q4-SUC2 DGA2 x3, without modification of lipid content. This work presents genetically modified strains of Y. lipolytica as suitable tools for direct conversion of industrial molasses into value added products based on single cell oils.

The close relation between Lactococcus and Methanosaeta is a keystone for stable methane production from molasses wastewater in a UASB reactor.

The up-flow anaerobic sludge blanket (UASB) reactor is a promising method for the treatment of high-strength industrial wastewaters due to advantage of its high treatment capacity and settleable suspended biomass retention. Molasses wastewater as a sugar-rich waste is one of the most valuable raw material for bioenergy production due to its high organic strength and bioavailability. Interpretation for complex interactions of microbial community structures and operational parameters can help to establish stable biogas production. RNA-based approach for biogas production systems is recommended for analysis of functionally active community members which are significantly underestimated. In this study, methane production and active microbial community were characterized in an UASB reactor using molasses wastewater as feedstock. The UASB reactor achieved a stable process performance at an organic loading rate of 1.7~13.8-g chemical oxygen demand (COD,·L(-1) day(-1); 87-95 % COD removal efficiencies), and the maximum methane production rate was 4.01 L-CH4·at 13.8 g-COD L(-1) day(-1). Lactococcus and Methanosaeta were comprised up to 84 and 80 % of the active bacterial and archaeal communities, respectively. Network analysis of reactor performance and microbial community revealed that Lactococcus and Methanosaeta were network hub nodes and positively correlated each other. In addition, they were positively correlated with methane production and organic loading rate, and they shared the other microbial hub nodes as neighbors. The results indicate that the close association between Lactococcus and Methanosaeta is responsible for the stable production of methane in the UASB reactor using molasses wastewater.

Selection and identification of oleaginous yeast isolated from soil, animal feed and ruminal fluid for use as feed supplement in dairy cattle.

UNLABELLED: The purpose of this study was to select oleaginous yeast for microbial lipid production. Sixty-four yeast isolates were obtained from soil (GSY1-12), animal feeds (FDY1-21), and ruminal fluid (RMY1-31) using yeast extract peptone dextrose (YPD) agar. The cultivation of these isolates on nitrogen limited-medium revealed that GSY2 to GSY6, GSY10, FDY2, FDY12 and FDY14 accumulated lipid over 20% of dry biomass. Therefore, they were preliminarily classified as oleaginous yeast. In subsequent experiment, an 8 × 3 factorial in completely randomized design was conducted to examine the effect of eight oleaginous yeast strains and three nitrogen sources (peptone, (NH4 )2 SO4 , urea) on lipid accumulation when using molasses as substrate. The result illustrated that only GSY3 and GSY10 accumulated lipid over 20% of biomass when using peptone or (NH4 )2 SO4 but urea did not. However, GSY10 gave higher biomass and lipid yield than GSY3 (P < 0·05). Identification of GSY10 using 26S rDNA illustrated that GSY10 belongs to Trichosporon asahii. Fatty acid profiles of this strain contained unsaturated fats up to 62·5% of which oleic acid (C18:1 ) was predominant. In conclusion, T. asahii GSY10 was the most promising oleaginous yeast for microbial lipid production from molasses. SIGNIFICANCE AND IMPACT OF THE STUDY: This study illustrated the ability of T. asahii GSY10 to utilize molasses and (NH4 )2 SO4 for synthesizing and accumulating cellular lipid of which oleic acid (C18:1 ) was predominant. This yeast would be used for microbial lipid production used as feed supplement in dairy cattle.

Safety and efficacy of milk and molasses enemas in the emergency department.

BACKGROUND: Increased scrutiny is occurring from regulatory agencies about the use of nonsterile enema preparations in the emergency department (ED) for constipation. This includes the "off-label" use of milk and molasses (M&M) enemas, as there are no reported data in the medical literature to determine safety and efficacy. OBJECTIVES: To evaluate the success and complication rates of administering M&M enemas in the ED. METHODS: This was a structured retrospective study at two EDs over 8 years. Primary success was defined as the patient having a bowel movement. Secondary measures of success included improved pain score by 2 or more points or lowering of a heart rate initially over 100 beats/min by 20 or more beats/min. Complications included: hemodynamic compromise, increased pain, electrolyte disturbances, bacteremia, bowel perforation, rectal pain or bleeding, cardiac dysrhythmias, anaphylaxis, electrolyte disturbances, dizziness or syncope, or hospital admission for issues surrounding enema. RESULTS: There were 2013 enemas given, of which 261 were M&M enemas; 214 were given alone. Success rates defined only as bowel evacuation for M&M enemas alone were 87.9% (188/214) and, when used after other treatment failures, were 82.4% (28/34) successful. Five additional patients improved with the secondary measures (90.2% success). There were 8/261 complications (3.1%), of which four had an increased heart rate, two had decreased blood pressure, one had an increased pain score, and one subsequently developed a fever. CONCLUSION: M&M enemas have a low complication rate when used in the ED.

Optimization of carbon and nitrogen medium components for biomass production using non-Saccharomyces wine yeasts.

UNLABELLED: The impact of different nitrogen and carbon sources on biomass production of the non-Saccharomyces wine yeast species Lachancea thermotolerans, Metschnikowia pulcherrima and Issatchenkia orientalis was assessed. Using a molasses-based medium, yeast extract and corn steep liquor as well as ammonium sulphate and di-ammonium phosphate (DAP) as nitrogen sources were compared in shake-flask cultures. A medium with 20 g l⁻¹ sugar (diluted molasses) and 500 mg l⁻¹ total yeast assimilable nitrogen, from yeast extract, gave the highest biomass concentrations and yields. Invertase pretreatment was required for cultures of M. pulcherrima and I. orientalis, and respective biomass yields of 0.7 and 0.8 g g⁻¹ were achieved in aerobic bioreactor cultures. The absence of ethanol production suggested Crabtree-negative behaviour by these yeasts, whereas Crabtree-positive behaviour by L. thermotolerans resulted in ethanol and biomass concentrations of 5.5 and 11.1 g l⁻¹, respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: Recent studies demonstrate that non-Saccharomyces yeasts confer positive attributes to the final composition of wine. However, optimal process conditions for their biomass production have not been described, thereby limiting commercial application. In this study, industrial media and methods of yeast cultivation were investigated to develop protocols for biomass production of non-Saccharomyces yeast starter cultures for the wine industry.