An investigation was carried out to study whether long-chain fatty acids (LCFAs) have an effect on digestion of waste sludge under anaerobic conditions. Four different kinds of LCFAs were used in this study. The 18 carbon series with 0, 1, 2 and 3 double bonds were studied to evaluate the degree of saturation on fatty acid degradation. Due to their molecular structure, unsaturated LCFAs are more soluble than saturated LCFAs. Oleic, linoleic, linolenic acid with an ascending number of double bonds were tested as representatives for three different degrees of saturation. In addition, stearic acid, a saturated fatty acid was also tested. LCFAs were added to sewage sludge at concentrations ranging from 5% to 20% on a weight basis and the pH, solids reduction and COD reduction were determined. The results suggested that in addition to degrading in the digesters, all unsaturated acids contributed additional solids removal, compared to the control group. In contrast, stearic acid did not affect the solids removal. The COD reduction was similar to solids reduction in that additional COD was destroyed when unsaturated LCFAs were added to the sludge. The mechanism for additional solids reduction is not known. / Master of Science

Finding a source from which high-energy-density biofuels can be derived at an industrial scale has become an urgent challenge for renewable energy production. Some microorganisms can produce free fatty acids (FFA) as precursors towards such high-energy-density biofuels. In particular, photosynthetic cyanobacteria are capable of directly converting carbon dioxide into FFA. However, current engineered strains need several rounds of engineering to reach the level of FFA production for it to be commercially viable. Thus, new chassis strains that require less engineering are needed. Although more than 140 cyanobacterial genomes are sequenced, the natural potential of these strains for FFA production and excretion has not been systematically estimated. In relation to the above-mentioned problems, we developed the first in silico screening method (FFASC) that evaluates the cyanobacterial strains’ potential for FFA production based on the strains’ proteome, which for the first time allows non-experimental selection of the most promising chassis for cyanofactories. The solution is based on the original problem formulation, optimization and ranking. To provide developers and researchers easy means for evaluation and assessment of the cyanobacterial strains potential for production of FFA, we developed the BioPS platform. In addition to being able to compare capacity for FFA production of any novel strain against 140 pre-valuate strains, BioPS can be used to explore characteristics and assessment rules in play for an individual strain. This is the first tool of this type developed. Finally, we developed a novel generic in silico method (PathDES) for ranking and selection of the most suitable pathways / sets of metabolic reactions, which suggests genetic modifications for improved metabolic productivity. The method heavily relies on optimization and integration of disparate information in a novel manner. It has been successfully used in connection with FFASC for design of cyanofactories. In conclusion, this study has contributed novel and unique methods, and tools for the field of bioinformatics, with applications towards the metabolic design of cyanofactories. We believe that these will be of good use to researchers and technology developers in this field.

Many individuals presumed to have non-alcoholic fatty liver disease (NAFLD) consume moderate amounts of alcohol; however, little is known regarding patterns of alcohol use and how drinking behaviors may influence liver fat. We conducted a cross-sectional study of 2,475 participants of the Framingham Heart Study who underwent computed tomography (CT) to define liver fat. We performed multivariable-adjusted logistic regression models for the association between different alcohol drinking patterns, including the average alcoholic drinks/week, frequency of alcohol use, usual quantity of alcohol consumed, maximum drinks consumed in 24 hours, and binge drinking behavior, and CT-defined hepatic steatosis. We excluded heavy alcohol users defined as women who drink > 14 drinks/week and men who drink > 21 drinks/week. We also performed an analysis specific to beverage type (beer, wine, or liquor/spirit drinks).The prevalence of hepatic steatosis in our study sample (mean age ± standard deviation (SD) 49.8±10.2, 50.3% women) was 17.5%. Among individuals with presumed NAFLD, binge drinking occurred in 25.4% of individuals. In adjusted models, the odds of hepatic steatosis increased by 20% for each SD increase in the number of alcoholic drinks consumed per week (OR 1.20; 95% confidence interval (CI) 1.08, 1.36). Frequency of alcohol use (drinking days/week) was also associated with hepatic steatosis (OR 1.09; 95% CI 1.03, 1.15). The odds of hepatic steatosis increased by 15% for each SD increase in the maximum drinks per week (OR 1.15; 95% CI 1.02, 1.30). In the beverage specific analysis, alcohol use patterns were associated with hepatic steatosis among beer drinkers, but no significant associations were observed among wine drinkers. Conclusions: Even after excluding heavy alcohol users from our sample, alcohol use contributed to liver fat, which suggests alcohol-related liver fat may be present among individuals presumed to have NAFLD. Additional prospective studies are needed to validate our findings and to determine if more comprehensive alcohol use screening tools should be used in practice or clinical trial settings. / 2020-06-03T00:00:00Z

BACKGROUND: Intelligence, as a measure of cognitive ability, is influenced by genetics and environment. Fluid intelligence, as an aspect of general intelligence, describes the ability to solve novel problems and is less reliant on previous knowledge and experience compared to other aspects of intelligence. Fluid intelligence is a particular useful indicator in studies of diverse populations, as fluid intelligence indicators are less likely than indicators of other aspects of intelligence to be significantly influenced by cultural factors, educational level, and language. Although fluid intelligence was previously thought to be primarily modulated by genetics, recent studies have shown that environment and its many factors have a greater role in shaping this aspect of cognition. Factors associated with a low-income environment, including dietary habits, are of interest when investigating effects on fluid intelligence in mothers from a low socioeconomic status population. METHODS: Participants were used from the Transgenerational Health Research InitiatiVE at Boston Medical Center. The Automated Self-Administered 24-Hour Dietary Assessment Tool online reporting questionnaire was used to collect self-reported dietary intake from mothers two times during participation in the study, once prenatally and once postpartum. The Weschler Abbreviated Scale of Intelligence Second Edition subtests of matrix reasoning and block design were used to assess fluid intelligence and were administered either prenatally or postpartum. A paired t-test was performed for determining statistical significance of fatty acid intake in the prenatal period versus postpartum period. Regression analysis was performed using stepwise selection to measure the correlation between fluid intelligence composite scores and fatty acid intake. RESULTS: No significant correlation was found between fluid intelligence composite scores and dietary intake of stearic, oleic, linoleic, and linolenic acid. Significant differences were found between prenatal and postpartum intake of oleic acid (omega-9) (p=0.0325) and linolenic acid (omega-3) (p=0.0065). CONCLUSION: The findings from this study suggest no correlation between fluid intelligence composite scores and dietary intake of stearic, oleic, linoleic, and linolenic acid. However, the findings do suggest a significant difference between prenatal and postpartum dietary intake of oleic (omega-9) and linolenic (omega-3) acid. Repeating this study on a larger sample population with complete data (demographics, diet intake, and fluid intelligence) could provide additional evidence for a correlation between fatty acid intake and fluid intelligence.

The multifunctional fatty acid (FA) binding protein, Cluster of Differentiation 36 (CD36), has been found to be expressed in a variety of tissues where it is involved in multiple fat-related biological processes, such as lipid metabolism in mammals and the detection of lipid-like pheromones in insects. As identified in the apical membranes of taste cells, along with functional evidence in behavioral and cellular level, its involvement in the gustatory FAs detection is suggested. Nonetheless, whether CD36 acts as a direct lipid sensor or as a chaperone protein that facilitates the function of FA-activated G protein coupled receptors (GPCRs), such as taste cell expressing GPR120, remains to be determined. To characterize the role of CD36 in FA signaling, either as a primary receptor or in concert with GPCRs, I utilized human embryonic kidney 293 (HEK293) cell lines that express the different combination of the LCFA receptor GPR120 and CD36. By using intracellular calcium imaging, the presence of CD36 increased the cell sensitivity to LA slightly in GPR120+ cells. Treating the CD36+GPR120+ cells with CD36 inhibitor, sulfo-N-succinimidyl oleate (SSO), resulted in a large reduction, but not abolishment of the LA activated response, which was absent in CD36+GPR120- cells. To investigate the role of CD36 in FA transduction specifically in taste, a mouse taste bud-derived (TBD) cell line, TBD-a1, was used. Knockdown of CD36 by RNA interference in these cells reduced but did not eliminate their intracellular calcium responses to LA. In vivo, isolated taste cells from CD36-KO mice and WT mice were compared for their FA sensitivity. CD36-KO cells were capable of responding to LA with the concentration-response curve not shifted significantly compared to WT cells. However, SSO significantly reduced the LA response in WT mice. At the behavioral level, responsiveness to LA in CD36-KO mice was not eliminated comparing to WT mice after formation of a conditioned taste aversion to LA. These data suggest that CD36 is a protein that facilitates the activation of GPR120 by FAs instead of a primary receptor for FAs itself. In the taste system, CD36 is not required but may facilitate activity in FAs responsive pathways.

Millions of pounds of venison are harvested each year in the United States. Over 12,000,000 pounds of dressed venison are harvested during the regular season each year in the State of Utah. The hunters of venison contribute approximately 10 1/2 billion dollars to the economy of the state for licenses, lodging, transportation, and other expense of hunting. In many cases this source of meat is a significant part of the household meat supply. Venison is often wasted, however, because of its undesirable flavor. The lack of knowledge as to the causes of variation in venison flavor has prompted this study. Research into tho causes of variation in venison flavor can contribute significantly to the problems of undesirable flavors and waste by determining the cause and distribution of factors which are responsible for these variations. This primary basic information may aid the hunter in his selection of animals to harvest. Suggestions as to age, sex, season of harvest, and physical condition of the animal may be applicable.

Importance of project: A sweet hazelnut flavor, a pliant texture, and large, evenly distributed "eyes" characterize high quality Swiss of Emmenthaler cheese. The typical sweet flavor is chiefly due to bacteria which produce propionic acid, acetic acid, and carbon dioxide. The eyes are formed from the gas, mainly carbon dioxide, produced by these and other bacteria. Krett and Stine (20) have found that the lower fatty acid content of a Swiss cheese generally indicates its quality. A study of factors which may influence the amount and ratios of the volatile acids should be helpful in determining manufacturing and curing procedures which will give a fine flavored product. Purpose of investigation Commercially, Swiss cheese is usually made from raw or heat-treated milk. Experimentally, hydrogen peroxide treated milk has shown some promise. A comparison of these three milk treatments was made to determine the effect they have on the volatile fatty acid content and cheese quality. Some successful cheesemakers add no prepared cultures of propionic acid bacteria (Propionibacterium shermanii); some add small amounts, while others advocate larger inoculums. Cheese in this experiment was made with varying amounts of added Propionibacterium shermanii culture to study the relationship to the lower fatty acid content, eye formation, and quality. This experiment is a study of the butyric, propionic, and acetic acid content of 4-month old cheese as affected by the above mentioned milk treatments and Propionibacterium shermanii culture variations.

Streptomyces coelicolor produces fatty acids for both primary metabolism and for production of the components of natural products such as undecylprodiginine. Primary metabolism makes the longer and predominantly branched-chain fatty acids, while undecylprodiginine utilizes shorter and almost exclusively straight chain fatty acids. The first step in fatty acid biosynthetic process is catalyzed by FabH (β-ketoacyl synthase III), which catalyzes a decarboxylative condensation of an acyl-CoA primer with malonyl-acyl carrier protein (ACP). The resulting 3-ketoacyl-ACP product is reduced by NADPH-dependent FabG into 3-hydroxyacyl-ACP, which is dehydrated by FabA to form enoyl-ACP. The NADH-dependent FabI (InhA) completes the cycle. Subsequent rounds of elongations in the pathways are catalyzed by the condensing enzyme FabF. For undecylprodiginine biosynthesis in S. coelicolor, homologues of the condensing enzymes (FabH and FabF) and the ACP (FabC) are encoded by redP, redR and redQ respectively in the red gene cluster. The genes encoding 3-ketoacyl-ACP reductase (FabG), 3-hydroxyacyl-ACP dehydratase (FabA), and enoyl-ACP reductase (FabI), are putatively shared between fatty acid and undecylprodigine biosynthesis, since the corresponding genes are not present within the red gene cluster of S. coelicolor. RedP is proposed to initiate biosynthesis of undecylprodiginine alkane chain by condensing an acetyl-CoA with a malonyl-RedQ, in contrast to FabH which process a broad range of acyl-CoA with malonyl-FabC. The 3-keto group of the resulting 3-ketoacyl-RedQ is then reduced to provide butyryl-RedQ, presumably by the type II FAS enzymes FabG, FabA and FabI. These enzymes would not differentiate between straight and branched-chain substrates, and have equal preference for FabC and RedQ ACPs. RedR would then catalyze four subsequent elongation steps with malonyl-RedQ, with appropriate 3-keto group processing after each step. The proposed role and substrate specificities of condensing enzymes RedP and FabH have not been investigated in S. coelicolor. The genes encoding FabG, FabA, and FabI have not been characterized in Streptomyces. Analysis of the S. coelicolor genome sequence has revealed the presence of one fabI gene (SCO1814, encoding an enoyl-ACP reductase), and three likely fabG genes (SCO1815, SCO1345, and SCO1346, encoding β-ketoacyl-ACP reductase). In the current study the substrates specificities of both RedP and FabH were determined from assays using pairings of two acyl-CoA substrates (acetyl-CoA and isobutyryl-CoA) and two malonyl-ACP substrates (malonyl-RedQ and malonyl-FabC) (FabC is a dedicated ACP for fatty acid biosynthesis and RedQ for undecylprodiginine biosynthesis in S. coelicolor). For RedP, activity was only observed with a pairing of acetyl-CoA and malonyl-RedQ. No activity was observed with isobutyryl-CoA consistent with the proposed role for RedP and the observation that acetyl CoA-derived prodiginines predominate in S. coelicolor. Malonyl-FabC is not a substrate for RedP, indicating that ACP specificity is one of the factors that permit a separation between prodiginine and fatty acid biosynthetic processes. In contrast to RedP, FabH was active with all pairings but demonstrated the greatest catalytic efficiency with isobutyryl-CoA using malonyl-FabC. Lower catalytic efficiency was observed using an acetyl-CoA and malonyl-FabC pairing consistent with the observation that in streptomycetes, a broad mixture of fatty acids are biosynthesized, with those derived from branched chain acyl-CoA starter units predominating. Diminished but demonstrable FabH activity was also observed using malonyl-RedQ, with the same preference for isobutyryl-CoA over acetyl-CoA, completing biochemical and genetic evidence that in the absence of RedP this enzyme can also play a role in prodiginine biosynthesis, producing branched alkyl chain prodiginines. The identification and characterization of both enzymes FabG and FabI was also carried out. A series of straight and branched-chain β-ketoacyl and enoyl substrates tethered to either NAC or ACP were synthesized and used to elucidate the functional role and substrate specificity of these enzymes. Kinetic analysis demonstrates that of the three S. coelicolor enzymes, SCO1815 and SCO1345 have NADPH-dependent β-ketoacyl-reductase activity, in contrast to SCO1346, which has NADH-dependent β-ketoacyl-reductase activity. Spectrophotometric assays revealed that all three FabGs are capable of utilizing both straight and branched-chain β-ketoacyl-NAC substrates. These results are consistent with FabGs role in fatty acid and undecylprodiginine biosynthesis, wherein it processes branched-chain for primary metabolism as well as straight-chain products for undecylprodiginine biosynthesis. LC/MS assays demonstrate that these FabG enzymes do not discriminate between primary metabolism ACP (FabC) and secondary metabolism ACP (RedQ) (except for SCO1345, which does not have any activity with RedQ). This relaxed substrate specificity allows these enzymes to process 3-ketoacyl-FabC substrates for fatty acid biosynthesis as well as 3-ketoacyl-RedQ substrates for undecylprodiginine biosynthesis. Similar to FabG, spectrophotometric and LC/MS assays were also carried out to elucidate the functional role and substrate specificity of S. coelicolor FabI. The kinetic analyses demonstrate that SCO1814 has NADH-dependent enoyl-ACP reductase activity. Spectrophotometric and LC/MS assays demonstrated that FabI does not differentiate between straight and branched-chain substrates, and has equal preference for FabC and RedQ ACPs. These observations provide experimental support for the hypothesis that these enzymes are shared and process the intermediates in the elongation cycle of both fatty acid and undecylprodiginine biosynthesis. In summary, these studies have demonstrated the activity of enzymes RedP, FabH, FabG and FabI (InhA) previously uncharacterized in S. coelicolor and clarified their role in fatty acid and undecylprodiginine biosynthesis.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第17896号 / 農博第2019号 / 新制||農||1017(附属図書館) / 学位論文||H25||N4792(農学部図書室) / 30716 / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 菅原 達也, 教授 左子 芳彦, 教授 澤山 茂樹 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18327号 / 農博第2052号 / 新制||農||1022(附属図書館) / 学位論文||H26||N4834(農学部図書室) / 31185 / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 河田 照雄, 教授 金本 龍平, 教授 入江 一浩 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM