Single cell oil production by a novel yeast Trichosporon mycotoxinivorans for complete and ecofriendly valorization of paddy straw

Background: Oleaginous yeasts can be grown on different carbon sources, including lignocellulosic hydrolysate containing a mixture of glucose and xylose. However, not all yeast strains can utilize both the sugars for lipogenesis. Therefore, in this study, efforts were made to isolate dual sugar-utilizing oleaginous yeasts from different sources. Results: A total of eleven isolates were obtained, which were screened for their ability to utilize various carbohydrates for lipogenesis. One promising yeast isolate Trichosporon mycotoxinivorans S2 was selected based on its capability to use a mixture of glucose and xylose and produce 44.86 ± 4.03% lipids, as well as its tolerance to fermentation inhibitors. In order to identify an inexpensive source of sugars, nondetoxified paddy straw hydrolysate (saccharified with cellulase), supplemented with 0.05% yeast extract, 0.18% peptone, and 0.04% MgSO4 was used for growth of the yeast, resulting in a yield of 5.17 g L−1 lipids with conversion productivity of 0.06 g L−1 h−1 . Optimization of the levels of yeast extract, peptone, and MgSO4 for maximizing lipid production using Box­Behnken design led to an increase in lipid yield by 41.59%. FAME analysis of single cell oil revealed oleic acid (30.84%), palmitic acid (18.28%), and stearic acid (17.64%) as the major fatty acids. Conclusion: The fatty acid profile illustrates the potential of T. mycotoxinivorans S2 to produce single cell oil as a feedstock for biodiesel. Therefore, the present study also indicated the potential of selected yeast to develop a zero-waste process for the complete valorization of paddy straw hydrolysate without detoxification

Relationship between Dyslipidemia, Cultural Factors, and Cardiorespiratory Fitness in Schoolchildren / Relação entre Dislipidemia, Fatores Culturais e Aptidão Cardiorrespiratória em Escolares

Abstract Background: The presence of dyslipidemia and behavioral aspects are determinants of cardiovascular risk, especially in childhood and adolescence. Objective: To verify possible relationships between dyslipidemia, cultural factors, and cardiorespiratory fitness (CRF) in schoolchildren. Methods: This cross-sectional study evaluated a sample of 1,254 children and adolescents between the ages of 7 and 17 from the South of Brazil, 686 of whom were female. Dyslipidemia was defined as increased levels of at least one of the following lipid profile parameters: triglycerides (TG), total cholesterol (TC) and fractions of high (HDL-c) and low-density lipoprotein (LDL-c). Cultural aspects were evaluated by a self-reported questionnaire. Data were analyzed by logistic regression, considering the odds ratios (OR) and confidence intervals (CI) at 95%. Results: The results revealed a high prevalence of dyslipidemia (41.9%), which was associated with female sex (OR: 1.56; IC: 1.24-1.96) and overweight/obese status (OR: 1.55; IC: 1.20-2.00). When lipid profile parameters were evaluated separately, high levels of LDL-c were observed to be associated with sedentary school transport (OR: 1.59; IC: 1.20-2.09). Schoolchildren who were overweight/obese had higher chances of elevated levels of TC (OR: 1.40; IC: 1.07-1.84) and TG (OR: 3.21; IC: 1.96-5.26). HDL-c was shown to be related to high television time (OR: 1.59; IC: 1.00-2.54). Conclusion: Alterations in lipid parameters are associated with cultural factors, especially those related to sedentary lifestyle and low levels of CRF.

Resumo Fundamento: A presença de dislipidemia e os aspectos comportamentais são fatores determinantes do risco cardiovascular, sobretudo na infância e adolescência. Objetivos: Verificar possíveis relações entre dislipidemia, fatores culturais e aptidão cardiorrespiratória (APCR) em escolares. Métodos: São sujeitos deste estudo transversal 1.254 crianças e adolescentes do Sul do Brasil, sendo 686 do sexo feminino, com idade entre 7 e 17 anos. Foi considerada dislipidemia a presença de níveis aumentados em pelo menos um dos parâmetros do perfil lipídico: triglicerídeos (TG), colesterol total (CT) e frações de alta (HDL-c) e baixa densidade (LDL-c). Os aspectos culturais foram avaliados por meio de questionário autorreferido pelo escolar. Os dados foram analisados pela regressão logística, considerando os valores de razão de chances (odds ratio; OR) e intervalos de confiança (IC) para 95%. Resultados: Foi encontrada elevada prevalência de dislipidemia (41,9%), a qual esteve associada com o sexo feminino (OR: 1,56; IC: 1,24-1,96) e com a presença de sobrepeso/obesidade (OR: 1,55; IC: 1,20-2,00). Quando os componentes do perfil lipídico foram avaliados de forma separada, observou-se que altos níveis de LDL-c se associaram ao deslocamento sedentário para a escola (OR: 1,59; IC: 1,20-2,09). Escolares com sobrepeso/obesidade apresentam maiores chances de elevação nos níveis de CT (OR: 1,40; IC: 1,07-1,84) e TG (OR: 3,21; IC: 1,96-5,26). O HDL-c apresentou associação com o elevado tempo em frente à televisão (OR: 1,59; IC: 1,00-2,54). Conclusão: A presença de alteração nos parâmetros lipídicos associa-se com fatores culturais, especialmente voltados ao sedentarismo e baixos níveis de APCR.

Effect of synthetic and natural media on lipid production from Fusarium oxysporum

Background: Dependence on fossil resources, for the production of fuels and energy, has resulted in environmental and financial problems, which require our immediate action in order to reverse the situation. Use of renewable sources for the production of fuels and energy is an important alternative with biodiesel remains as one of the promising options. Aim of this work is to evaluate the fungus Fusarium oxysporum for its potentials to accumulate microbial lipids when grown on synthetic media and saccharified sweet sorghum stalks. Results: The effect of different carbon sources, nitrogen sources and C/N ratio on the lipid production was initially examined, which resulted in a lipid concentration of 4.4 g/L, with lipid content of 42.6% w/w. Sweet sorghum stalks were able to support growth and lipid production of the fungus, both as carbon source and as nitrogen source. It was also shown that saccharification of the dried stalks is an important step to increase lipid production. Removal of the remaining stalk solids enabled the lipid production during cultivation in increased initial solids of up to 16 w/w. This resulted in a lipid production of 3.81 g/L. Conclusions: It was demonstrated that F. oxysporum can be used as an efficient oleaginous microorganism, with sweet sorghum serving as an excellent raw material for the cultivation of the fungus. The lipids obtained during this work were also found to have a fatty acid profile with good potentials to be used for biodiesel production.

Effect of initial pH of medium with potato wastewater and glycerol on protein, lipid and carotenoid biosynthesis by Rhodotorula glutinis

Background: Rhodotorula glutinis is capable of synthesizing numerous valuable metabolites with extensive potential industrial usage. This paper reports the effect of initial culture medium pH on growth and protein, lipid, and carotenoid biosynthesis by R. glutinis. Results: The highest biomass yield was obtained in media with pH 4.0­7.0, and the value after 72 h was 17.2­19.4 gd.w./L. An initial pH of the medium in the range of 4.0­7.0 has no significant effect on the protein (38.5­41.3 g/100 gd.w.), lipid (10.2­12.7 g/100 gd.w.), or carotenoid (191.7­202.9 µg/gd.w.) content in the biomass or on the profile of synthesized fatty acids and carotenoids. The whole pool of fatty acids was dominated by oleic (48.1­53.4%), linoleic (21.4­25.1%), and palmitic acids (13.0­15.8%). In these conditions, the yeast mainly synthesized torulene (43.5­47.7%) and ß-carotene (34.7­38.6%), whereas the contribution of torularhodin was only 12.1­16.8%. Cultivation in medium with initial pH 3.0 resulted in a reduction in growth (13.0 gd.w./L) and total carotenoid (115.8 µg/gd.w.), linoleic acid (11.5%), and torularhodin (4.5%) biosynthesis. Conclusion: The different values of initial pH of the culture medium with glycerol and deproteinized potato wastewater had a significant effect on the growth and protein, lipid, and carotenoid biosynthesis by R. glutinis.

Effects of nutritional conditions on lipid production by cyanobacteria

ABSTRACT The present study evaluated the effects of the culturing media and the levels of nitrogen and phosphorus on the growth, biomass productivity and lipid production of four species of Microcystis (M. novacekii, M. aeruginosa, M panniformis and M. protocystis). The lipid extract was obtained by refluxing with dichloromethane (Soxhlet). The biomass and biomass productivity yields were maximized with ASM-1 medium treatment enriched with nitrogen and/or phosphorus (0.25-0.65 g/L and 25-50.7 mg/L d-1, respectively). The lipid extract yields from M. panniformis and M. novacekii were inversely correlated with the concentration of nitrogen and directly correlated with the concentration of phosphorus (35.8 % and 31.7 %). The lipid extract yield from M. aeruginosa was inversely correlated with the nutrient concentration (23.3 %). M. protocystis exhibited a higher lipid content in the control medium (41.5 %) than in the nitrogen-enriched media. The recorded results show that a nutrient-poor culture medium favours cell growth and stimulates lipid accumulation, which directly affects the cost of cultivation by reducing nutrient consumption. All studied species may serve as biomass sources for biodiesel production, although M. protocystis exhibited the highest lipid production. Further studies are necessary to determine the composition of the recorded lipid extract.

Cultivation of Scenedesmus dimorphus for C/N/P removal and lipid production

Background CO2 emission, water pollution and petroleum shortage are the issues coming with the development of industry. A cost effective system was constructed to fix the CO2 in flue gas (15% CO2), remove nitrogen and phosphorus from manure wastewater and produce biofuels at the same time. The significant cultivation conditions were selected by Plackett-Burman design, and then optimized with central composite design. Results Optimum culture condition was predicted at light intensity of 238 µmol·m- 2·s- 1, TN of 152 mg·L- 1, inoculum density of 0.3 g·L- 1, under which the measured CO2 fixation rate, total nitrogen and phosphorus removing rate, and lipid content were 638.13 mg·L- 1·d- 1, 88.16%, 73.98% and 11.9%, respectively. The lipid content was then enhanced to 24.2% by a nitrogen starvation strategy. Conclusion A cultivation strategy was suggested to achieve effective C/N/P removal from flue gas and manure wastewater, and meanwhile obtained high lipid content from microalgal biomass.

Caracterização do intumescimento de sistemas líquido-cristalinos de fase lamelar de monoleína e água contendo polihexametilenobiguanida / Characterization of swelling of lamellar phases of monoolein and water containing polyhexamethylenebiguanide

A monoleína é um lipídeo polar capaz de absorver água e formar sistemas líquido-cristalinos, os quais são utilizados como sistemas de liberação para administração de vários fármacos. Neste estudo foi avaliado o potencial de sistemas de fase lamelar constituídos por monoleína e água para veicular polihexametilenobiguanida (PHMB). A formação dos sistemas líquido-cristalinos foi caracterizada por microscopia de luz polarizada. Estudos de intumescimento foram realizados gravimetricamente em várias condições avaliando-se os efeitos de parâmetros como pH, força iônica e temperatura do meio de imersão. O processo de intumescimento foi caracterizado através da obtenção dos perfis de intumescimento e análise de sua cinética, além da determinação da capacidade máxima de intumescimento dos sistemas. Os sistemas de fase lamelar foram obtidos em presença de PHMB, os quais absorveram água rapidamente de acordo com cinética de segunda ordem e sofreram transição de fase, formando a fase cúbica. O intumescimento dos sistemas não foi influenciado pela presença do fármaco nos vários meios de imersão estudados, exceto pela imersão em meio ácido, no qual a presença do PHMB aumentou a captação de água. O intumescimento dos sistemas contendo PHMB não foi afetado pela força iônica do meio de imersão, porém foi diminuído com o aumento da temperatura. Desta maneira, sistemas líquido-cristalinos de monoleína e água foram obtidos e o processo de intumescimento foi caracterizado. Os sistemas apresentaram potencial para serem propostos como sistemas de liberação para administração de PHMB e estudos de liberação de fármacos serão realizados futuramente.

Monoolein is a polar lipid that absorbs water and forms liquid crystalline systems that are used as drug delivery systems for different medications. The aim of the present study was to investigate lamellar phases formed by monoolein and water as potential vehicles for the administration of polyhexamethylene biguanide (PHMB). Lamellar phase systems formed by monoolein and water containing PHMB were characterized by polarizing microscopy. Swelling studies were performed gravimetrically under different conditions for the evaluation of the effects of pH, ionic strength and temperature. Analyses of swelling profiles, swelling kinetics and maximum swelling capacity were performed. The lamellar phase systems of monoolein and water obtained in the presence of PHMB absorbed water very quickly following second-order swelling kinetics and formed a cubic phase. The swelling of the systems was not influenced by the presence of the drug in the immersion media studied, except under acidic conditions, in which the drug exhibited increased water uptake. The swelling of systems containing PHMB was not affected by the ionic strength of the immersion media, but was reduced with an increase in temperature. Liquid crystalline systems of monoolein and water were obtained and swelling behavior was investigated. The systems exhibited the potential for use as a drug delivery system for PHMB administration. However, further drug-release studies should be performed.

Optimization of lipid enriched biomass production from oleaginous fungus using response surface methodology.

Oleaginous microorganisms have emerged as potential sources of oils for biodiesel production. To replenish as an alternative to the vegetable oils, higher lipid accumulating strain coupled with process optimization is indispensable. In the present study, response surface methodology (RSM) based central composite design (CCD) was used for optimization of lipid content from oleaginous fungus Aspergillus sp. Maximum lipid yield of 73.07% (w/w) was achieved at 3% (v/v) inoculum volume, pH 5, glucose 1% (w/v), urea 0.5 % (w/v) and incubation time of 5 (days). Biomass (2.08 g/L) having a lipid content of 73.07 % (w/w) with major constituents of hexadecanoic acid methyl ester and 9-Octadecenoic acid methyl ester were obtained. The lipid composition signifies that from the oleaginous microbe are highly encouraging and desirable to be considered as diesel substitute.

Participación del sistema endocanabinoide en el desarrollo de obesidad / A role for the endocannabinoid system in obesity

Endocannabinoids are the endogenous ligands for the cannabinoid receptors type 1 and 2. These membrane receptors are responsible for the psychotropic effects of Cannabis Sativa, when bound to its active component known as (-)-Δ9-tetrahydro-cannabinol. Cannabinoid receptors, endocannabinoids and the enzymes catalyzing their biosynthesis and degradation, constitute the endocannabinoid system (ECS), which has a remarkable role controlling energy balance, both at central nervous system and peripheral tissues. The ECS regulates food ingestion by stimulating a network of orexigenic neurons present in the hypothalamus and reinforcing motivation and reward to food consumption in the nucleus accumbens. Regarding peripheral tissues, this system controls lipid and glucose metabolism at different levels, reduces energy expenditure and leads energy balance to fat storage. Metabolic alterations, includ-ing excessive accumulation of abdominal fat, dyslipidaemia and hyperglicaemia, are suggested to be associated to a hyperactivated ECS. Since obesity is one of the major health problems in modern societies, in this review we discuss the role of the endocannabinoid system in metabolic pathways associated to control mechanisms of energy balance and its involvement in overweight and obesity. In addition, we also discuss therapeutic possibilities and emergent problems due to cannabinoid receptor type 1 antagonism utilized as treatment for such alterations.

Influência dos níveis séricos de IGF-I e de testosterona sobre o perfil lipídico e glicêmico em homens acromegálicos / Influence of serum IGF-I and testosterone on lipid and glycemic profile in acromegalic men

OBJETIVOS: Investigar a influência do IGF-I e testosterona sobre o perfil lipídico e glicêmico em homens acromegálicos. MÉTODOS: Foram avaliados 15 homens acromegálicos. RESULTADOS: Os pacientes hipogonádicos apresentaram HDL-c mais baixo e triglicérides, LDL-c, glicemia, GH e IGF-I mais elevados. Os valores de IGF-I correlacionaram-se inversamente com HDL-c (r = - 0,57, p = 0,04) e diretamente com triglicerídeos (r = 0,62, p = 0,01) e glicemia (r = 0,66, p = 0,008), enquanto a testosterona correlacionou-se diretamente com HDL-c (r = 0,52, p = 0,05) e inversamente com triglicerídeos (r = - 0,57, p = 0,02); LDL (r = - 0,53, p = 0,04) e glicemia (r = - 0,54, p = 0,03). O IGF-I e a testosterona correlacionaram-se inversamente (r = - 0,585, p = 0,028). CONCLUSÃO: Estes resultados sugerem que a intervenção mais importante na redução do risco cardiovascular nesses pacientes é o controle da atividade da doença.

OBJECTIVES: To evaluate the influence of IGF-I and testosterone on the lipid profile and glycemia in acromegalic men. METHODS: Fifteen acromegalic men were studied. RESULTS: The hypogonadic patients presented lower HDL-c and higher tryglicerides, LDL-c, glycemia, GH and IGF-I. Serum IGF-I was inversely correlated with HDL-c (r = - 0.57, p = 0.04) and directly with TG (r = 0.62, p = 0.01) and glycemia (r = 0.66, p = 0.008), whereas serum testosterone correlated directly with HDL-c (r = 0.52, p = 0.05) and inversely with TG (r = - 0.57, p = 0.02), LDL-c (r = - 0.53, p = 0.04) and fasting blood glucose (r = - 0.54, p = 0.03). IGF-I and testosterone were inversely correlated (r = - 0.585, p = 0.028). CONCLUSION: These results suggest that the most important intervention in reducing cardiovascular risk in these patients is to control the activity of the disease.

Restrição protéica na prenhez: efeitos relacionados ao metabolismo materno / Protein restriction in pregnancy: effects related to dam metabolism

Foram avaliadas as alterações no metabolismo materno durante a prenhez em ratas Wistar, prenhes e não-prenhes, submetidas à restrição protéica, que receberam dietas isocalóricas (15,74 kJ/g), controle ou hipoprotéica (17 por cento versus 6 por cento), distribuídas em quatro grupos (n = 7), quais sejam: controle não-prenhe (CNP) e prenhe (CP) e hipoprotéico não-prenhe (HNP) e prenhe (HP), do 1º ao 18º dia de prenhez. Parâmetros bioquímicos, hormonais e relacionados à síntese de lipídios foram considerados. Utilizou-se ANOVA a duas vias seguido de teste Tukey-HSD e teste t de Student, significância de p < 0,05. A restrição protéica elevou a síntese de lipídios e a atividade da enzima málica (EM) no fígado (FIG) e reduziu a massa ( por cento) e a razão lipí+dio/glicogênio nesse tecido, bem como reduziu a ingestão protéica (total e por cento), o conteúdo ( por cento) de lipídios na glândula mamária (GMA), as proteínas e a albumina séricas, com consequente redução nas massas da placenta e fetos. A prenhez reduziu a proteinemia, a albuminemia, a síntese de lipídios, a atividade da EM, os lipídios e o glicogênio no FIG. Mas elevou a massa corporal final, a massa ( por cento) do tecido adiposo gonadal (GON), do FIG e da GMA, e reduziu a massa ( por cento) da carcaça (CARC), a síntese e o conteúdo de lipídios no GON e, na GMA, o conteúdo de lipídios. A insulinemia elevou-se na prenhez, com glicemia reduzida, caracterizando resistência hormonal. A leptina e a prolactina também se elevaram na prenhez, sendo o aumento maior no HP. A restrição protéica na prenhez modificou o metabolismo materno, alterando a síntese de lipídios no FIG e o perfil hormonal, além de reduzir a massa da placenta e dos fetos.

Metabolism alterations were evaluated in female Wistar rats (dams) during pregnancy. Pregnant and non-pregnant dams submitted to protein restriction, were fed isocaloric (15.74 kJ/g), control or hypoproteic (17 percent vs. 6 percent) diets, and distributed in four Groups (n=7) as follows: non-pregnant control (NPC), pregnant control (PC), non-pregnant hypoproteic (NPH), and pregnant hypoproteic (PH); from Day 1 to Day 18 of pregnancy. Biochemical, hormonal and metabolic parameters related to lipid synthesis were assessed. The two-way ANOVA, followed by Tukey-HSD and Student-t tests were used, with a significance of p< 0.05. Protein restriction elevated lipid synthesis and malic enzyme (ME) activity in the liver, and reduced mass and the lipid/glycogen ratio in this tissue; it also lowered protein ingestion (total and percent), lipid content ( percent) in the mammary gland (MAG), serum proteins and albumin, with consequent reduction of placenta and fetal masses. Pregnancy reduced serum protein and albumin concentrations, lipid synthesis, ME activity, hepatic lipid and glycogen content. However, it increased final body mass; increased relative masses of gonad (GON), liver and MAG; but reduced lipid synthesis and content of GON, lipid content of MAG and the relative mass of carcass. Pregnancy Insulinemia increased during pregnancy with reduced glycemia, characterizing hormonal resistance. Leptin and prolactin were also increased during pregnancy, being the highest increase in observed in HP rats. Protein restriction in pregnancy modified maternal metabolism, altering lipid synthesis in the liver and hormonal profile and decreasing the placenta and fetus masses.

Dislipidemia associada à terapia anti-retroviral em pacientes com AIDS / Dyslipidemia associated with antiretroviral therapy in AIDS patients

A disponibilidade da terapia anti-retroviral tem resultado em um enorme declínio nas taxas de morbidade e mortalidade dos pacientes infectados pelo vírus da imunodeficiência humana. entretanto, tal terapia tem sido associada a efeitos metabólicos adversos, como a dislipidemia; sendo assim, indivíduos com doença arterial coronariana devem ser identificados e tratados. Este artigo faz uma revisão das anormalidades dos lipídios e das lipoproteínas associadas ao uso dos inibidores de proteases, sobre o possível mecanismo da dislipidemia associada a estes inibidores e usa o protocolo do programa de educação para tratamento do colesterol em adultos(National Cholesterol Education Program Adult Treatment Panel III Guidelines) para o acompanhamento do paciente com dislipidemia.

Regulation of glucose utilization and lipogenesis in adipose tissue of diabetic and fat fed animals: effects of insulin and manganese.

In order to evaluate the modulatory effects of manganese, high fat diet fed and alloxan diabetic rats were taken and the changes in the glucose oxidation, glycerol release and effects of manganese on these parameters were measured from adipose tissue. An insulin-mimetic effect of manganese was observed in the adipose tissue in the controls and an additive effect of insulin and manganese on glucose oxidation was seen when Mn2+ was added in vitro. The flux of glucose through the pentose phosphate pathway and glycolysis was significantly decreased in high fat fed animals. Although the in vitro addition of Mn2+ was additive with insulin when 14CO2 was measured from control animals, it was found neither in young diabetic animals (6-8 weeks old) nor in the old (16 weeks old). Both insulin and manganese caused an increased oxidation of carbon-1 of glucose and an increase of its incorporation into 14C-lipids in the young control animals; the additive effect of insulin and manganese suggests separate site of action. This effect was decreased in fat fed animals, diabetic animals and old animals. Manganese alone was found to decrease glycerol in both the control and diabetic adipose tissue in in vitro incubations. The results of the effects of glucose oxidation, lipogenesis, and glycerol release in adipose tissue of control and diabetic animals of different ages are presented together with the effect of manganese on adipose tissue from high fat milk diet fed animals.

Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries OMEGA 3 E OMEGA 6 / Antioxidant effect of phenolic compounds of spices on the OMEGA 3 and OMEGA 6

Dentro da perspectiva da utilização de compostos fenólicos como antioxidantes naturais para minimizar os efeitos in vitro e in vivo do processo oxidativo dos lípides insaturados, foi realizada a monitoração dietética de duas dietas ricas em lípides das séries "OMEGA"3 e "OMEGA"6 e a suplementação de um chá de uma mistura de especiarias, em ratos Wistar, com o objetivo de verificar a influência dos compostos fenólicos, presentes nas especiarias, sobre o metabolismo de ácidos graxos das séries "OMEGA"3 e "OMEGA"6. Extratos e frações das especiarias mostarda, canela e erva doce foram obtidos e tiveram suas atividades antioxidantes testadas em sitemas aquoso (co-oxidação de sustratos com o uso de ácido linoléico/"BETA"-caroteno)...

Géis de monoleína/água para veiculação de fármacos protéicos: estudos microscópicos, reológicos e de liberação in vitro / Monoolein/water gels as delivery systems for proteic drugs: microscopic, rheological and in vitro delivery studies

Géis de fase cúbica de monoleína e água têm sido propostos como sistemas de liberação de fármacos com diferentes características, incluindo moléculas protéicas e peptídicas. O presente trabalho estudou a incorporação de lactoferrina, usada como molécula protéica modelo em várias concentrações em géis de fase cúbica de monoleína e água. A influência da lactoferrina nos géis de monoleína/água foi avaliada por microscopia de luz polarizada e estudo de suas propriedades reológicas, asssim como estudos de liberação in vitro foram realizados. A fase cúbica foi observada na presença da lactoferrina sendo que esta proteína não modificou as transições de fase dos géis, quando observados ao microscópio de luz polarizada...

Mechanisms in anti-inflammation and resolution: the role of lipoxins and aspirin-triggered lipoxins

Multicellular host responses to infection, injury or inflammatory stimuli lead to the formation of a broad range of chemical mediators by the host. The integrated response of the host is essential to health and disease; thus it is important to achieve a more complete understanding of the molecular and cellular events governing the formation and actions of endogenous mediators of resolution that appear to control the duration of inflammation. Lipoxins are trihydroxytetraene-containing lipid mediators that can be formed during cell-cell interactions and are predominantly counterregulators of some well-known mediators of inflammation. Since this circuit of lipoxin formation and action appears to be of physiological relevance for the resolution of inflammation, therapeutic modalities targeted at this system are likely to have fewer unwanted side effects than other candidates and current anti-inflammatory therapies. Here, we present an overview of the recent knowledge about the biosynthesis and bioactions of these anti-inflammatory lipid mediators

Inhibitory effect of propranolol on lipid synthesis in gonadectomized male hamster flank organs

Background. This papaer describes the inhibitory effect produced by propanolol pre-treatment on lipid synthesis in flank organs from intact, gonadectomized, and isoproterenol-treated male hamsters. Furthermore, the effect induced by the same treatments on gland sebum composition is reported. Methods. Different groups of male hamsters were injected daily with propranolol, isoproterenol or propranolol plusisoproterenol. Treatment-effect was evaluated determining the in vitro incorporation of radioactive acetate into lipids in hamster flank organs from intact and castrated animals. Additionally, radiolabeled lipids were isolated and identified using TLC and autoradiography as methods. Results. demonstrate that castration significantly decreases lipid synthesis in male hamster flank organs. In addition, propanolol treatment inhibits such synthesis in glands from intact, gonadectomized, and isoproterenol-treated animals. However, isoproterenol treatment was ineffective when compared to intact or gonadectomized control vehicle-treated animals. Lipid classes isolated and identified lipids either in castrated or in drug-treated animals were phospholipids, cholesterol, monoglycerides, fatty acids, waxes and cholesterol esters. Conclusions. Results indicate an inhibitory effect induced on lipid synthesis by ß-adrenergic receptor antagonist; however, ß-adrenergic agonists drugs do not stimulate it. Data suggest a permissive role of adrenergic hormones on lipid synthesis in intact and in gonadectomized animals. Futhermore, castration decreased the synthesis, suggesting that a tight coupling between ß-adrenergic receptors and androgen receptors may be a prerequisite for lipogenesis in this tissue. Pre-treatment does not modify sebum composition in gonadectomized animal glands. These data support the evidence that activation of ß-adrenergic receptors could be an independent factor in the lipid composition regulation process

Effect of FSH and insulin on lipogenesis in cultures of Sertoli cells from immature rats

Follicle-stimulating hormone (FSH) and insulin regulate glycide metabolism in Sertoli cells, thus stimulating lactate production. These stimulatory effects of FSH and insulin do not require protein synthesis, suggesting a modulation of enzyme activity and/or regulation of glucose transport. The present investigation was performed to characterize the hormonal control of lipid metabolism in Sertoli cells. The data indicate that FSH and insulin have a regulatory effect on lipid metabolism in Sertoli cells. After 8 h of preincubation with insulin (5 mug/ml), the activity of the enzyme ATP-citrate lyase in sultured Sertoli cells was increased from 0.19 to 0.34 nmol NAD+ formed mug protein(-1) min(-1). FSH (100 ng/ml) had no effect on this enzyme. Glycerol phosphate dehydrogenase activity was not affected by any of the hormones tested. When Sertoli cells from 19-day old rats were incubated with [1,2-14C] acetate for 90 or 360 min, the [14C] label was present predominantly in triglyceride and phospholipid fractions with minor amounts in other lipids. In Sertoli cells pretreated for 16 h with insulin and FSH, an increase in acetate incorporation into lipids was observed. Most of the label was in esterified lipids and this percentage increased with the time of treatment; this increase was remarkable in triglycerides of control cells (18.8 percent to 30.6 percent). Since Sertoli cell triglycerides participate in the control of spermatogenesis, the present data suggest that the hormonal control of lipid metabolism in Sertoli cells is important not only for maintaining the energy of the cell itself, but also for the control of the spermatogenesis process.

Influence of cultural conditions on lipid production by mutant strain of Rhodotorula glutinis MTCC 1151.

Mutant of Rhodotorula glutinis MTCC 1151 was found to produce high level of lipid (63.6% of biomass) as compared to parent strain (56.7% biomass). The lipid synthesizing capacity of mutant of R. glutinis was evaluated with different glucose concentrations, nitrogen sources, incubation time, and aeration-agitation. Maximum lipid yield (63.6% of biomass) was found with 5% glucose using ammonium sulfate (0.2%) as a nitrogen source under shake-flask conditions (50 ml broth in 250 ml conical flask at 125 rpm) after 4 days of incubation at 28 degrees C. The ability of ammonium sulfate to replace comparatively very costly yeast extract is highly appreciable.

Lipid production by Candida Y-1.

Ten oleaginous yeasts were isolated from sources like fruits, flowers, curd whey and soil samples. Lipid production varied from 24 to 71.2% of dry weight of cell biomass. Strain Y-1, which was isolated from curd whey, produced the highest amount of lipid. It was identified belonging to the genus Candida. The optimal cultural conditions for lipid production by Candida Y-1 were found to be glucose (5%) as carbon source, ammonium sulfate (1%) as nitrogen source, pH 4.5, and temperature 28 degrees C under shake-flask conditions (125 rpm).