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1.
World J Microbiol Biotechnol ; 36(1): 17, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31912247

RESUMO

In this study, the effects of limited and excess nitrate on biomass, lipid production, and fatty acid profile in Messastrum gracile SE-MC4 were determined. The expression of fatty acid desaturase genes, namely stearoyl-ACP desaturase (SAD), omega-6 fatty acid desaturase (ω-6 FAD), omega-3 fatty acid desaturase isoform 1 (ω-3 FADi1), and omega-3 fatty acid desaturase isoform 2 (ω-3 FADi2) was also assessed. It was found that nitrate limitation generally increased the total oil, α-linolenic acid (C18:3n3) and total polyunsaturated fatty acid (PUFA) contents in M. gracile. The reduction of nitrate concentration from 1.76 to 0.11 mM increased the total oil content significantly from 32.5 to 41.85% (dry weight). Palmitic (C16:0) and oleic (C18:1) acids as the predominant fatty acids in this microalgae constituted between 82 and 87% of the total oil content and were relatively consistent throughout all nitrate concentrations tested. The expression of SAD, ω-6 FAD, and ω-3 FADi2 genes increased under nitrate limitation, especially at 0.11 mM nitrate. The ω-3 FADi1 demonstrated a binary up-regulation pattern of expression under both nitrate-deficient (0.11 mM) and -excess (3.55 mM) conditions. Thus, findings from this study suggested that limited or excess nitrate could be used as part of a cultivation strategy to increase oil and PUFA content following media optimisation and more efficient culture methodology. Data obtained from the expression of desaturase genes would provide valuable insights into their roles under excess and limited nitrate conditions in M. gracile, potentially paving the way for future genetic modifications.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos/análise , Microalgas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Biomassa , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/metabolismo , Regulação Enzimológica da Expressão Gênica , Metabolismo dos Lipídeos , Microalgas/genética , Microalgas/metabolismo , Ácido Oleico/metabolismo , Ácido Palmítico/metabolismo , Ácido alfa-Linoleico/metabolismo
2.
Bioresour Technol ; 300: 122649, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896045

RESUMO

Most natural astaxanthin is fatty acid-esterified in microalgae to prevent oxidation. However, the factors influencing astaxanthin esterification (AE) are poorly understood. In this study, obstacles to AE in Coelastrum sp. HA-1 were investigated. Only half of the astaxanthin molecules in HA-1 were esterified, but AE was stimulated with exogenous linoleic acid (LA) and ethanol treatment. Astaxanthin esters and total astaxanthin (TA) with exogenous LA were elevated to 3.82-fold and 2.18-fold of control levels, respectively. Treatment with 3% (v/v) ethanol enhanced transcription of the Δ12 fatty acid desaturase gene, which caused more oleic acid (OA) to be converted to LA. Furthermore, the contents of astaxanthin esters and TA were 2.42-fold and 1.61-fold control levels, respectively. These findings confirmed that AE was upregulated by increasing LA content. Thus, a large concentration of OA alone does not increase astaxanthin accumulation in HA-1, and a certain amount of LA was necessary for AE.


Assuntos
Ácido Linoleico , Xantofilas , Esterificação , Ácidos Graxos
3.
J Environ Manage ; 258: 110008, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929052

RESUMO

Microbial chain elongation (MCE) is a bioprocess that could utilise a mixed-culture fermentation to valorise organic waste. MCE converting ethanol and short chain fatty acids (SCFA; derived from organic waste) to caproate has been studied extensively and implemented. Recent studies demonstrated the conversion of SCFAs and methanol or ethanol into isomerised fatty acids as novel products, which may expand the MCE application and market. Integrating caproate and isomerised fatty acid production in one reactor system is theoretically feasible given the employment of a mixed culture and may increase the economic competence of MCE; however, the feasibility of such has never been demonstrated. This study investigated the feasibility of using two electron donors, i.e. methanol and ethanol, for upgrading SCFAs into isobutyrate and caproate concurrently in MCE Results show that supplying methanol and ethanol in MCE simultaneously converted acetate and/or butyrate into caproate and isobutyrate, by a mixed-culture microbiome. The butyrate supplement stimulated the caproate production rate from 1.5 to 2.6 g/L.day and induced isobutyrate production (1.5 g/L.day). Further increasing ethanol feeding rate from 140 to 280 mmol carbon per litre per day enhanced the direct use of butyrate for caproate production, which improved the caproate production rate to 5.9 g/L.day. Overall, the integration of two electron donors, i.e. ethanol and methanol, in one chain-elongation reactor system for upgrading SCFAs was demonstrated. As such, MCE could be applied to valorise organic waste (water) streams into a wider variety of value-added biochemical.


Assuntos
Caproatos , Etanol , Ácidos Graxos , Ácidos Graxos Voláteis , Fermentação , Isobutiratos , Metanol
4.
Medicine (Baltimore) ; 99(2): e18626, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914044

RESUMO

Detection of the chronic kidney disease (CKD) progression can begin early intervention to improve the prognosis of severe non-alcoholic fatty liver disease (NAFLD). This bi-directional cross-sectional study evaluates the roles of fatty acid-binding protein (FABP) and retinol binding protein (RBP4), which are produced from inflamed liver, adipose tissue and immune cells, for the prediction of CKD progression in severe NAFLD. Ninety severe NAFLD patients with hypertension and proteinuria (NAFLDHTN) were enrolled and divided into CKD (n = 39) and non-CKD groups (n = 51). Among 39 NAFLDHTN patients, 18 cases were categorized as CKD progression group. In comparison with CKD stable group (n = 21), the positive correlation between fold change values of hepatic fibrotic score (KPa), urinary FABP4 or urinary RBP4 versus severity of albuminuria were noted among CKD progression group. On multivariate analysis, high body mass index (BMI, >25 kg/m), high hepatic fibrosis score (>9.5 KPa), high urinary level of vascular cell adhesion molecule-1 (VCAM-1, >2239 µg/g cr), high urinary level of FABP4 (>115 ng/g cr) and high urinary level of RBP4 (>33.5 mg/g cr) are 5 independent predictors for progressive CKD during 24 months of follow-up. Synergetic effect was noted among these 5 risk factors for the prediction of CKD progression in NAFLDHTN patients. The in vitro experiments revealed that both FABP4 and RBP4 directly enhanced albumin-induced ER stress and apoptosis of human renal tubular epithelial cell line HK-2 cells and human podocytes cell lines. Through clinical and experimental approaches, this study revealed new 5 synergetic predictors including high BMI, hepatic fibrosis score, urinary level of VCAM-1, urinary level of FABP4 and RBP4, for the CKD progression in severe NAFLD patients with hypertension and proteinuria.


Assuntos
Ácidos Graxos/urina , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Proteínas de Ligação ao Retinol/urina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminúria/epidemiologia , Índice de Massa Corporal , Linhagem Celular Transformada , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/epidemiologia , Índice de Gravidade de Doença , Molécula 1 de Adesão de Célula Vascular/urina , Adulto Jovem
5.
Bioresour Technol ; 301: 122762, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31972402

RESUMO

To assess the potential of Chlorella sp. GN1 for producing biodiesel raw materials in flat plate photobioreactors (FPPs) outdoors, we optimized the nitrogen sources and concentrations for the growth of the algae. The effects of different light paths of FPPs on the growth, lipid accumulation, and fatty acids of Chlorella sp. GN1 were also studied. As the light path of the FPPs was reduced, the alga could accumulate lipids rapidly, achieving high lipid content and lipid productivity outdoors. The highest lipid content obtained was 53.5%, when the light path was 5 cm. In addition, the lipid productivity was 66.7 mg L-1 day-1. The main fatty acids were C16/C18, accounting more than 90% of the total fatty acids. Results showed that Chlorella sp. GN1 had the ability to accumulate large quantities of lipids in FPPs outdoors and was a promising microalgal species for biofuel production.


Assuntos
Chlorella , Microalgas , Biocombustíveis , Biomassa , Ácidos Graxos , Luz , Lipídeos , Nitrogênio , Fotobiorreatores
6.
Bioresour Technol ; 297: 122402, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761627

RESUMO

This study reports comparative evaluation of the growth and DHA productivity of the thraustochytrid strain Thraustochytriidae PKU#Mn16 fermented with seven different substrate feeding strategies. Of these strategies, fed-batch fermentation of the mixed substrate (glucose & glycerol) yielded the maximum growth (52.2 ±â€¯1.5 g/L), DHA yield (Yp/s: 8.65) and productivity (100.7 ±â€¯2.9 mg/L-h), comparable with those of previously reported Aurantiochytrium strains. Transcriptomics analyses revealed that glucose upregulated some genes of the fatty acid synthase pathway whereas glycerol upregulated a few genes of the polyketide synthase pathway. Co-fermentation of the mixed substrate differentially regulated genes of these two pathways and significantly enhanced the DHA productivity. Furthermore, some genes involved in DNA replication, phagosome, carbon metabolism, and ß-oxidation were also found to alter significantly during the mixed-substrate fermentation. Overall, this study provides a unique strategy for enhancing growth and DHA productivity of the strain PKU#Mn16 and the first insight into the mechanisms underlying mixed-substrate fermentation.


Assuntos
Carbono , Ácidos Docosa-Hexaenoicos , Vias Biossintéticas , Ácidos Graxos , Fermentação
7.
Water Res ; 170: 115309, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31812814

RESUMO

This study investigated the chemical and genetic mechanisms of anaerobic fermentation of waste activated sludge (WAS) with CaO2 addition at ambient temperature. The microbial community structures, key microorganisms, functional profiles and related carbohydrate-active enzymes were further revealed according to metagenomic sequencing combining with 16S rRNA gene amplicon sequencing. Results showed that the prolonged period of alkaline condition generated from CaO2 contributed significantly to the continuous destruction of WAS, and the oxidative environment caused by CaO2 further enhanced flocs dissolution. This synergistic effect also significantly changed the microbial community. Oxidation contributed more than the alkaline condition to the decline of microbial diversity, while the effect of alkaline condition was greater than that of oxidation in the change of microbial community structure. The key enhanced genes associated with fatty acid biosynthesis pathways with CaO2 addition were highlighted. Three kinds of high-abundance acetyl-CoA carboxylase genes and eleven kinds of synthetase, hydrolase, lyase and oxidoreductase genes promoted by CaO2 were distributed throughout each branch of fatty acid biosynthesis pathway (ko00061). Moreover, carbohydrate binding modules (CBMs) and glycoside hydrolases (GHs) were the top two carbohydrate-active enzymes (CAZymes) improved by CaO2 addition. CaO2 can also effectively promote the function of lysozyme and the metabolism of several monosaccharides. This work provides a deep insight into the advantage of CaO2 in promoting sludge solubilization and acidification at the genetic levels, thus expanding the application of CaO2 in sludge treatment and resource recovery.


Assuntos
Ácidos Graxos , Esgotos , Anaerobiose , Ácidos Graxos Voláteis , Fermentação , Redes e Vias Metabólicas , RNA Ribossômico 16S , Temperatura Ambiente
8.
Bioresour Technol ; 297: 122439, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31810740

RESUMO

In the present study, a combination of phytohormones (indole acetic acid and kinetin) was augmented in nitrogen-limited medium to achieve higher biomass and lipid yield in Graesiella emersonii NC-M1 and Chlorophyta sp. NC-M5. This condition was recorded with a 2.3- and 2.5-fold increase in biomass and lipid yield for Graesiella emersonii NC-M1 compared to the nitrogen-limited condition. Also, this condition showed a 1.6- and 1.08-fold increase in lipid yield and neutral lipid compared to the standard condition. Phytohormones addition also reduced oxidative damage caused by nitrogen-limitation and enhanced monounsaturated fatty acid content. Further, a 5.2- and 3.17-fold enhance in expression level of GPAT and DGAT genes were noticed under nitrogen-limited medium supplemented with phytohormones compared to control.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Diacilglicerol O-Aciltransferase , Ácidos Graxos , Glicerol , Ácidos Indolacéticos , Cinetina , Lipídeos , Nitrogênio , Fosfatos
9.
J Sci Food Agric ; 100(3): 1358-1361, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31617214

RESUMO

BACKGROUND: There is renewed interest in quinoa as a potential source of vegetable oils; however, there is no information about how environmental conditions affect its fatty acid composition, a critical indicator of its oil quality. The fatty acid concentrations of four cultivars adapted to temperate environments were compared at three sowing dates to evaluate the effect of environmental conditions during the seed-filling period on the variation in oil quality. RESULTS: The interaction between cultivar and sowing date was the main source of variation explaining the changes in the lipid content and fatty acid concentrations in quinoa. Most of the variation in the concentration of unsaturated fatty acids was attributed to the temperature and solar radiation during the seed-filling period; cultivar-specific responses to photo-thermal conditions were observed among the sea-level quinoa cultivars evaluated. CONCLUSION: The lipid content and concentration of fatty acids in quinoa are affected by sowing date. This effect is exerted through changes in temperature and solar radiation conditions. This managing practice can therefore be used to achieve quinoa oil with different qualities. © 2019 Society of Chemical Industry.


Assuntos
Chenopodium quinoa/química , Óleos Vegetais/química , Chenopodium quinoa/classificação , Chenopodium quinoa/metabolismo , Chenopodium quinoa/efeitos da radiação , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Luz , Valor Nutritivo , Óleos Vegetais/metabolismo , Sementes/química , Sementes/classificação , Sementes/metabolismo , Sementes/efeitos da radiação , Temperatura Ambiente
10.
Water Res ; 169: 115218, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677435

RESUMO

Effective sludge treatment with bioenergy production is attracting increasing interests as large quantities of waste activated sludge (WAS) are produced during the wastewater treatment. In this study, a new biotechnical process for converting the WAS alkaline fermentation liquor (WASAFL) into valuable, easy-separated medium chain fatty acids (MCFAs) through chain elongation (CE) was investigated, which may provide a new insight into sludge treatment. In the process, ethanol was served as the electron donor (EDs) and WASAFL were main electron acceptors (EAs). The MCFAs productions were investigated under three different ED to EA ratios (i.e., 1:2, 1:1 and 2:1). The result showed that MCFAs production was increased from 2.88 ±â€¯0.01 to 5.28 ±â€¯0.18 g COD/L with the increase of ED to EA ratio. However, the highest MCFA selectivity was achieved at 72.9% when the ED to EA ratio was 1:1. The decrease in the selectivity at high ED:EA ratio is mainly due to the production of higher alcohol (i.e., n-butanol and n-hexanol). The thermodynamic analysis confirmed all CE processes for MCFAs production from WASAFL were exothermic reactions, with the spontaneity and energy release of the reactions increased with the ethanol level. The microbial community analysis showed that the relative abundances of Clostridium, Oscillibacter, Leptolinea and Exilispira were positively correlated with the MCFAs production. The metagenomic analysis suggested that both the reverse ß-oxidization pathway and fatty acid biosynthesis pathway contributed to the CE process in the studied system. The functional enzymes were mainly associated within Clostridium, with Clostridium Kluyveri, Clostridium botulinum and Clostridium magnum being likely the key species responsible for the CE process.


Assuntos
Ácidos Graxos , Esgotos , Ácidos Graxos Voláteis , Fermentação , Concentração de Íons de Hidrogênio , Termodinâmica , Águas Residuárias
11.
Water Res ; 169: 115215, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678751

RESUMO

The production of biochemicals from renewables through biorefinery processes is important to reduce the anthropogenic impact on the environment. Chain elongation processes based on microbiomes have been successfully developed to produce medium-chain fatty acids (MCFA) from organic waste streams. Yet, the sustainability of chain elongation can still be improved by reducing the use of electron donors and additional chemicals. This work aimed to couple lactate production and subsequent chain elongation to decrease chemicals input such as electron donors and hydroxide for pH control in repeated-batch food waste fermentation. Food waste with adjusted pH was used as substrate and fermentation proceeded without pH control. During fermentation, lactate was first formed through the homolactic pathway and then converted to fatty acids (FA), mainly n-butyrate and n-caproate. The highest n-caproate carbon selectivities (mmol C/mmol CFA) and production rates were 38% and 4.2 g COD/L-d, respectively. Hydroxide input was reduced over time to a minimum of 0.47 mol OH-/mol MCFA or 0.79 mol OH-/kg CODFA. Lactate was a key electron donor for chain elongation and its conversion was observed at pH as low as 4.3. The microbiome enriched in this work was dominated by Lactobacillus spp. and Caproiciproducens spp. The high abundance of Caproiciproducens spp. and their co-occurrence with Lactobacillus spp. suggest Caproiciproducens spp. used lactate as electron donor for chain elongation. This work shows the production of n-caproate from food waste with decreased use of hydroxide and no use of exogenous electron donors.


Assuntos
Alimentos , Eliminação de Resíduos , Reatores Biológicos , Butiratos , Ácidos Graxos , Fermentação
12.
J Photochem Photobiol B ; 202: 111638, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733613

RESUMO

The present study investigates the phycoremediation potentials of two microalgal consortia (MAC1 and MAC2) for treating sewage water and producing biomass with high lipid, protein and chlorophyll contents. During the study, the microalgal strains were tested for lipid enhancement, biomass production and contaminant removal from wastewater. The microalgal consortia showed prolific growth in wastewater with 75% dilution and accumulated higher lipid content of 31.33% dry cell weight in MAC1. The maximum biomass (50% diluted wastewater) for both the consortia was 1.53 and 1.04 gL-1. Total chlorophyll (19.17-25.17 µg mL-1) and protein contents (0.12-0.16 mg mL-1) for both the consortia were found to be maximum in 75 WW. MAC1 was capable of removing 86.27% of total organic carbon and 87.6% of chemical oxygen demand. Approximately, 94% of nitrate and phosphate contents were removed from the initial contents of wastewater. Heavy metal removal efficiency was also found to be better and showed 85.06% Cu, 75.2% Cr, 98.2% Pb, and 99.6% Cd removal by the algal consortia. Pyrolytic decomposition of algal consortia was observed using thermogravimetric analysis. The stepwise decomposition of algae indicated distinct losses of functional groups. The gas chromatography-mass spectrometric analysis revealed the majority of saturated fatty acids followed by monounsaturated and polyunsaturated fatty acids. Thus, the present study proved that both the consortia show tremendous potential for the treatment of domestic wastewaters with successive lipid enhancement for biodiesel production.


Assuntos
Biocombustíveis/análise , Ácidos Graxos/metabolismo , Microalgas/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos/métodos , Proteínas de Algas/metabolismo , Biomassa , Clorofila/análise , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Metais Pesados/química , Metais Pesados/metabolismo , Microalgas/metabolismo
13.
J Sci Food Agric ; 100(3): 1311-1319, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31742693

RESUMO

BACKGROUND: Intramuscular fat (IMF) and polyunsaturated fatty acids (PUFAs) have been thought to play a crucial role in improving meat quality. Considering the ability of pioglitazone hydrochloride (PGZ) to deposit fat, and the anti-stress capability of chromium methionine (CrMet), we combined these compounds to produce higher quality meat in poultry. A total of 3000 female chickens were divided into four groups (five replicates, each with 150 chickens): control, control plus15 mg·kg-1 PGZ, control plus 200 µg·kg-1 CrMet, and control plus15 mg·kg-1 PGZ plus 200 µg·kg-1 CrMet. The experiment lasted for 28 days. RESULTS: Compared to the control group and the PGZ group, the average daily gain (ADG) was significantly increased in the PGZ plus CrMet group, whereas the feed-to-gain ratio (F/G) was decreased from 0 to 14 days. Meanwhile, the redness value of breast muscle and IMF of thigh muscle increased in the PGZ plus CrMet group compared with the control group and these detections in the PGZ plus CrMet group exhibited highest value among the four groups. The cooking loss decreased in the breast muscle and thigh muscle after PGZ combined with CrMet in diets. The percentages of C16:1, C18:2n-6 and PUFAs increased in the PGZ plus CrMet group. The mRNA abundance of peroxisome proliferator activated receptor (PPAR) γ, PPAR coactivator 1 α, and fatty acid binding protein 3 was significantly enhanced with PGZ plus CrMet supplementation. CONCLUSION: Collectively, dietary supplementation with PGZ plus CrMet improved growth performance and meat quality by decreasing the cooking loss and increasing the IMF and PUFA levels. © 2019 Society of Chemical Industry.


Assuntos
Galinhas/metabolismo , Cromo/metabolismo , Suplementos Nutricionais/análise , Ácidos Graxos/metabolismo , Metionina/metabolismo , Músculo Esquelético/metabolismo , Pioglitazona/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/genética , Cromo/administração & dosagem , Culinária , Dieta/veterinária , Ácidos Graxos/química , Feminino , Metabolismo dos Lipídeos , Carne/análise , Metionina/administração & dosagem , Músculo Esquelético/química , Pioglitazona/administração & dosagem
14.
Arch Microbiol ; 202(1): 191-196, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31595323

RESUMO

A novel Gram-negative, aerobic, rod-shaped bacterium, RS19T, was isolated from rose rhizosphere soil. The strain was psychrophilic and showed good growth over a temperature range of 1-37 â„ƒ. Colonies on TSB agar were circular, smooth, mucoid, convex with clear edges and yellow. Phylogenetic analysis based on 16S rRNA gene sequences characterized RS19T in the genus Dyadobacter and showed that strain RS19T was most closely related to Dyadobacter psychrophilus CGMCC 1.8951T (97.4%) and Dyadobacter alkalitolerans CGMCC 1.8973T (97.1%). The average nucleotide identity values to the closest related species type strains were less than 84.0%. The DNA G + C content was 43.1 mol%, and the predominant respiratory menaquinone was MK-7. The major fatty acids were summed features 3 (C16:1ω7c and/or C16:1ω6c), iso-C15:0, C16:1ω5c and iso-C17:0 3-OH. Based on genotypic, phenotypic and chemotaxonomic data, strain RS19T is different from closely related species of the genus Dyadobacter. RS19T represents a novel species within the genus Dyadobacter, for which the name Dyadobacter luteus sp. nov. is proposed. The type strain is RS19T (= CGMCC 1.13719T = ACCC 60381T = JCM 32940T).


Assuntos
Cytophagaceae/classificação , Filogenia , Rizosfera , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Cytophagaceae/química , Cytophagaceae/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , RNA Ribossômico 16S/genética , Rosa/microbiologia , Análise de Sequência de DNA , Especificidade da Espécie , Vitamina K 2/análise
15.
J Sci Food Agric ; 100(3): 953-960, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31512245

RESUMO

BACKGROUND: 'Arauco' is the only autochthonous olive cultivar from Argentina. Little has been reported so far regarding the management of this crop. In this work, variations in fruit and chemical characteristics of olives harvested over a wide range of dates and seasons are reported for this cultivar at two sites in Mendoza province in central west Argentina. RESULTS: During the harvest periods studied, fruit oil content on a dry basis remained at its maximum and was stable, but fruit oil content on fresh basis increased as water content decreased with delay in harvest date. Harvest date affected the maturity index of fruits as well as the oxidative stability and phenolic content of oil. In contrast, the fatty acid profile was not consistently affected by harvest date. Environmental conditions, mainly the occurrence and intensity of frosts, strongly influenced oil quality as well as maturity with delay in harvest date. CONCLUSION: The most appropriate harvest time to obtain Arauco oil with a high oil yield and good chemical quality was before mid-May and with maturity index lower than 2. Fruits harvested after mid-May were exposed to minimum temperatures between -1.2 °C and - 4.0 °C, producing oil with low phenolic compounds and oxidative stability. © 2019 Society of Chemical Industry.


Assuntos
Frutas/química , Olea/crescimento & desenvolvimento , Azeite de Oliva/química , Argentina , Produção Agrícola , Ácidos Graxos/química , Frutas/crescimento & desenvolvimento , Olea/química , Oxirredução , Fenóis/química , Estações do Ano , Temperatura Ambiente , Fatores de Tempo
16.
Waste Manag ; 102: 40-47, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655329

RESUMO

Black soldier fly larvae (Hermetia illucens; BSFL) can convert organic wastes into a nutrient-rich biomass suitable in animal feed, which could be a way to achieve more sustainable production of food. However, little is known about how the diet fed to BSFL affects their nutritional value, especially their fatty acid composition. In this study, BSFL were fed 11 diets based on four different organic waste sources (mussels, bread, fish and food waste). Fatty acid and proximate composition (dry matter, crude fat, crude protein and ash) were analysed in the diets, in two-week-old larvae and substrate residues. Larval weight, survival and feed conversion were also recorded. The diet was found to affect all parameters investigated. Irrespective of diet, the larval fat consisted mainly of lauric acid and other saturated fatty acids and these were found to be synthesised by the larvae. However, both the fatty acid composition of the substrate, and the larval weight were found to affect the fatty acid profile of the larvae. In general, larvae with a higher weight contained a higher percentage of saturated fatty acids and a lower percentage of unsaturated fatty acids, such as eicosapentaenoic (EPA) and docosahexaenoic acid (DHA). It was concluded that the possibilities to tailor the fatty acid composition of the BSFL through the diet are limited; thus, the BSFL fat may not be suitable to replace fish oil, but has potential of inclusion in other food, feed and fuel products.


Assuntos
Eliminação de Resíduos , Simuliidae , Ração Animal , Animais , Dieta , Ácidos Graxos , Larva
17.
Arch Microbiol ; 202(1): 143-151, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31535159

RESUMO

A gram-stain-negative, aerobic, non-spore-forming, rod-shaped, non-motile bacterium strain R4HLG17T was isolated from Tamarix ramosissima roots growing in Kumtag desert. The strain grew at salinities of 0-16% (w/v) NaCl (optimum 5-6%), pH 5-9 (optimum 7) and at 16-45 °C. Based on 16S rRNA gene sequence similarity, strain R4HLG17T belonged to the family Halomonadaceae and was most closely related to Halomonas lutea DSM 23508T(95.1%), followed by Halotalea alkalilenta AW-7T(94.8%), Salinicola acroporae S4-41T(94.8%), Salinicola halophilus CG4.1T(94.6%), and Larsenimonas salina M1-18T(94.4%). Multilocus sequence analysis (MLSA) based on the partial sequences of 16S rRNA, atpA, gyrB, rpoD, and secA genes indicated that the strain R4HLG17T formed an independent and monophyletic branch related to other genera of Halomonadaceae, supporting its placement as a new genus in this family. The draft genome of strain R4HLG17T was 3.6 Mb with a total G + C content of 55.1%. The average nucleotide identity to Halomonas lutea DSM 23508T was 83.5%. Q-9 was detected as the major respiratory quinone and summed feature 8 (C18:1ω7c/C18:1ω6c), summed feature 3 (C16:1ω7c/C16:1ω6c), and C16:0 as predominant cellular fatty acids. On the basis of chemotaxonomic, phylogenetic, and phenotypic evidence, strain R4HLG17T is concluded to represent a novel species of a new genus within Halomonadaceae, for which the name Phytohalomonas tamaricis gen. nov., sp. nov., is proposed. The type strain is R4HLG17T (=ACCC 19929T=KCTC 52415T).


Assuntos
Halomonadaceae/classificação , Raízes de Plantas/microbiologia , Tamaricaceae/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Clima Desértico , Ácidos Graxos/análise , Halomonadaceae/química , Halomonadaceae/genética , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
18.
Waste Manag ; 102: 48-55, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669674

RESUMO

Citrus wax is a waste generated during the purification process of the citrus essential oil. A lot of citrus wax wastes are globally produced, despite this, its composition and properties are not well known. Here we present comprehensive results proving the chemical composition and the physical properties of citrus wax. Additionally, our study provides the basis for obtaining value-added products from citrus wax wastes. The qualitative/quantitative analysis revealed the presence of different compounds, which range from flavonoids, saponins, carbohydrates, unsaturated compounds, phenolic hydroxyls, and long-chain fatty acid esters. Given that citrus wax is a source of many bioactive compounds, they were preferably extracted with ethanol. The ethanolic extracts demonstrated the presence in citrus wax of different bioactives, such as 5-5'-dehydrodiferulic acid, 3,7-dimethylquercetin, 5,6-dihydroxy-7,8,3',4'-tetramethoxyflavone, tangeretin, and limonene. After the extraction of bioactives from citrus wax, a washed waxy material with high content of long-chain fatty acid esters was obtained. It was shown that this washed wax can be used for the production of biodiesel. The transesterification reactions in acid media was the preferred process because higher content of fatty acid methyl esters (such as hexadecanoic acid methyl ester and 9,12-octadecadienoic acid (Z,Z)-, methyl ester) were obtained. Currently, citrus wax does not have any industrial application, here we shown that under the concept of waste biorefinery, the citrus wax wastes are useful sources for producing value-added products such as bioactive compounds and biodiesel.


Assuntos
Citrus , Biocombustíveis , Esterificação , Ésteres , Ácidos Graxos
19.
Arch Microbiol ; 202(1): 55-61, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31463600

RESUMO

A novel actinomycete, strain PA1-10T, isolated from the leaf of Phyllanthus amarus collected from Bangkok, Thailand, was characterized taxonomically using a polyphasic approach. This strain contained the characteristics consistent with those of members of the genus Nonomuraea. It formed short rugose spore chain on aerial mycelium. The diamino acid in cell wall peptidoglycan was meso-diaminopimelic acid. Galactose, glucose, madurose, mannose, and ribose were found in whole-cell hydrolysates. Predominant menaquinones were MK-9 (H2), MK-9 (H4), and MK-9 (H6). Major cellular fatty acids were iso-C16:0 and C17:0 10-methyl. Phospholipid profiles were composed of phosphatidylinositol mannoside (PIM), lyso-phosphatidylethanolamine (lyso-PE), phosphatidylethanolamine (PE), methylphosphatidylethanolamine (PME), diphosphatidylglycerol (DPG), and phosphatidylglycerol (PG). The G + C content of DNA was 71.2 mol%. Strain PA1-10T showed the highest 16S rRNA gene sequence similarity with Nonomuraea candida JCM 15928T (98.35%) and shared the same node with Nonomuraea maritima JCM 18321T in the phylogenetic tree analysis. Based on the phenotypic characteristics, DNA-DNA relatedness, and average nucleotide identity (ANI), the strain is considered to represent a novel species of the genus Nonomuraea, for which the name Nonomuraea phyllanthi is proposed. The type strain is PA1-10T (= JCM 33073T = NBRC 112774T = TISTR 2497T).


Assuntos
Actinomycetales/classificação , Phyllanthus/microbiologia , Filogenia , Folhas de Planta/microbiologia , Actinomycetales/química , Actinomycetales/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tailândia
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117382, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31357053

RESUMO

Fourier transform infrared (FTIR) and Raman spectroscopic techniques were employed to analyze the biomolecular transitions and lipid accumulation in three freshwater green microalgal species, Monoraphidium contortum (M. contortum), Pseudomuriella sp. and Chlamydomonas sp. during various phases of their growth. Biomolecular transitions and lipid [hydrocarbons, triacylglycerides (TAGs)] accumulation within the microalgal cells were identified using second derivatives of the FTIR absorption spectroscopy. Second derivative analysis normalized and resolved the original spectra and led to the identification of smaller, overlapping bands. Both relative and absolute content of lipids were determined using the integrated band area. M. contortum exhibited higher accumulation of lipids than the other two species. The integrated band area of the vibrations from saturated (SFA) and unsaturated lipids (UFA) enabled quantification of fatty acids. The percentage of SFA and UFA was determined using GC, FTIR and Raman spectroscopy. From the spectral data, the order of increasing concentration of SFA among the three microalgal species was M. contortum > Chlamydomonas sp. >Pseudomuriella sp. The spectral results on fatty acids were consistent with the separation of lipids by gas chromatography. The results emphasized the significance of FTIR and Raman spectroscopic methods in monitoring the biomolecular transitions and rapid quantification of lipids, without the need for extraction of lipids.


Assuntos
Clorófitas , Lipídeos , Microalgas , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Biocombustíveis/análise , Clorófitas/química , Clorófitas/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Lipídeos/análise , Lipídeos/química , Microalgas/química , Microalgas/metabolismo
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