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Metabolic extremes provide opportunities to understand enzymatic and metabolic plasticity and biotechnological tools for novel biomaterial production. We discovered that seed oils of many Thunbergia species contain up to 92% of the unusual monounsaturated petroselinic acid (18:1Δ6), one of the highest reported levels for a single fatty acid in plants. Supporting the biosynthetic origin of petroselinic acid, we identified a Δ6-stearoyl-acyl carrier protein (18:0-ACP) desaturase from Thunbergia laurifolia, closely related to a previously identified Δ6-palmitoyl-ACP desaturase that produces sapienic acid (16:1Δ6)-rich oils in Thunbergia alata seeds. Guided by a T. laurifolia desaturase crystal structure obtained in this study, enzyme mutagenesis identified key amino acids for functional divergence of Δ6 desaturases from the archetypal Δ9-18:0-ACP desaturase and mutations that result in nonnative enzyme regiospecificity. Furthermore, we demonstrate the utility of the T. laurifolia desaturase for the production of unusual monounsaturated fatty acids in engineered plant and bacterial hosts. Through stepwise metabolic engineering, we provide evidence that divergent evolution of extreme petroselinic acid and sapienic acid production arises from biosynthetic and metabolic functional specialization and enhanced expression of specific enzymes to accommodate metabolism of atypical substrates.
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Acanthaceae , Ácidos Graxos Monoinsaturados , Proteínas de Plantas , Estearoil-CoA Dessaturase , Acanthaceae/metabolismo , Proteína de Transporte de Acila/metabolismo , Evolução Molecular , Ácidos Graxos Monoinsaturados/metabolismo , Mutagênese , Óleos de Plantas/química , Proteínas de Plantas/análise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/enzimologia , Estearoil-CoA Dessaturase/análise , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismoRESUMO
Rapeseed is a crop of global importance but there is a need to broaden the genetic diversity available to address breeding objectives. Radiation mutagenesis, supported by genomics, has the potential to supersede genome editing for both gene knockout and copy number increase, but detailed knowledge of the molecular outcomes of radiation treatment is lacking. To address this, we produced a genome re-sequenced panel of 1133 M2 generation rapeseed plants and analysed large-scale deletions, single nucleotide variants and small insertion-deletion variants affecting gene open reading frames. We show that high radiation doses (2000 Gy) are tolerated, gamma radiation and fast neutron radiation have similar impacts and that segments deleted from the genomes of some plants are inherited as additional copies by their siblings, enabling gene dosage decrease. Of relevance for species with larger genomes, we showed that these large-scale impacts can also be detected using transcriptome re-sequencing. To test the utility of the approach for predictive alteration of oil fatty acid composition, we produced lines with both decreased and increased copy numbers of Bna.FAE1 and confirmed the anticipated impacts on erucic acid content. We detected and tested a 21-base deletion expected to abolish function of Bna.FAD2.A5, for which we confirmed the predicted reduction in seed oil polyunsaturated fatty acid content. Our improved understanding of the molecular effects of radiation mutagenesis will underpin genomics-led approaches to more efficient introduction of novel genetic variation into the breeding of this crop and provides an exemplar for the predictive improvement of other crops.
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Brassica napus , Brassica rapa , Brassica napus/genética , Melhoramento Vegetal , Brassica rapa/genética , Genômica , Mutagênese/genética , Sementes/genética , Óleos de PlantasRESUMO
BACKGROUND: Infant formulas are typically manufactured using skimmed milk, whey proteins, and vegetable oils, which excludes milk fat globule membranes (MFGM). MFGM contains polar lipids, including sphingomyelin (SM). OBJECTIVE: The objective of this study was comparison of infant plasma SM and acylcarnitine species between infants who are breastfed or receiving infant formulas with different fat sources. METHODS: In this explorative study, we focused on SM and acylcarnitine species concentrations measured in plasma samples from the TIGGA study (ACTRN12608000047392), where infants were randomly assigned to receive either a cow milk-based infant formula (CIF) with vegetable oils only or a goat milk-based infant formula (GIF) with a goat milk fat (including MFGM) and vegetable oil mixture to the age ≥4 mo. Breastfed infants were followed as a reference group. Using tandem mass spectrometry, SM species in the study formulas and SM and acylcarnitine species in plasma samples collected at the age of 4 mo were analyzed. RESULTS: Total SM concentrations (â¼42 µmol/L) and patterns of SM species were similar in both formulas. The total plasma SM concentrations were not different between the formula groups but were 15 % (CIF) and 21% (GIF) lower in the formula groups than in the breastfed group. Between the formula groups, differences in SM species were statistically significant but small. Total carnitine and major (acyl) carnitine species were not different between the groups. CONCLUSIONS: The higher total SM concentration in breastfed than in formula-fed infants might be related to a higher SM content in human milk, differences in cholesterol metabolism, dietary fatty acid intake, or other factors not yet identified. SM and acylcarnitine species composition in plasma is not closely related to the formula fatty acid composition. This trial was registered at Australian New Zealand Clinical Trials Registry as ACTRN12608000047392.
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Carnitina , Cabras , Fórmulas Infantis , Leite Humano , Leite , Esfingomielinas , Humanos , Fórmulas Infantis/química , Animais , Carnitina/sangue , Carnitina/análogos & derivados , Leite Humano/química , Lactente , Esfingomielinas/sangue , Leite/química , Feminino , Masculino , Bovinos , Aleitamento Materno , Ésteres/sangue , Recém-Nascido , Óleos de Plantas/químicaRESUMO
BACKGROUND: Studies examining the potential association between cooking oil and frailty risk in older adults have produced conflicting outcomes. Therefore, our objective was to explore the relationship between cooking oil (vegetable and animal fat oils), changes in oil usage, and the risk of frailty in older adults. METHODS: We included 4,838 participants aged ≥ 65 years without frailty (frailty index < 0.25) from the 2011 wave of the Chinese Longitudinal Healthy Longevity Survey. Follow-up occurred in the 2014 and 2018 waves. Cox proportional hazard models were utilized to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) to examine the association between cooking oil and frailty. Additionally, we evaluated the effect of switching cooking oil on frailty during the follow-up period. RESULTS: During a median follow-up of 3.0 (2.8-6.9) years, 1,348 individuals (27.9%) developed frailty. Compared to those using vegetable oil, users of animal fat oil had a lower risk of frailty (HR = 0.72, 95% CI: 0.61-0.85). Participants who switched from vegetable oil to animal fat oil, as well as those consistently using animal fat oil, had lower risks of frailty with HRs of 0.70 (0.52-0.95) and 0.63 (0.51-0.77) respectively, compared to those who consistently used vegetable oil. Conversely, individuals who switched from animal fat oil to vegetable oil experienced an increased risk of frailty (HR: 1.41, 95% CI: 1.01-1.97). CONCLUSIONS: The utilization of animal fat oil in cooking exhibited a reduced frailty risk among older adults. Conversely, transitioning from animal fat oil to vegetable oil may elevate the risk. These findings propose that substituting vegetable oil with animal fat oil in the diet may safeguard against frailty.
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Culinária , Fragilidade , Humanos , Idoso , Masculino , Feminino , Fragilidade/epidemiologia , Fragilidade/prevenção & controle , Culinária/métodos , Estudos de Coortes , China/epidemiologia , Idoso Fragilizado , Idoso de 80 Anos ou mais , Estudos Longitudinais , Incidência , Óleos de Plantas , Modelos de Riscos ProporcionaisRESUMO
INTRODUCTION: Nowadays, food safety is regarded as one of the most critical global public health issues. Edible oil, a key ingredient in food processing, is widely used and consumed in every Ethiopian household. However, its safety is often overlooked. Currently, edible oil is produced in Ethiopia from small-scale operations to large industrial levels, as well as imported from other countries. OBJECTIVE: This study aimed to determine the levels of heavy metals and essential minerals in edible vegetable oils produced and marketed in Gondar City, Northwest Ethiopia. METHODS: A laboratory-based cross-sectional study was conducted from May to July 2021 in Gondar City. Seventeen edible oil samples were collected using simple random sampling techniques. Heavy metal content was determined using an atomic absorption spectrophotometer with the standard procedures and techniques after microwave digestion. The efficiency and validity of the method used were evaluated by determining the limit of detection (LOD), the limit of quantification (LOQ), accuracy, and precision. The collected data were entered into Microsoft Excel and transported to Stata for analysis. RESULT: A total of seventeen vegetable oil samples were analyzed. The accuracy of the method was evaluated by recovery studies, which ranged from 81 to 115%, and the relative standard deviations were found to be below 15%. The concentrations of Zn, Cu, Fe, Cd, and Pb were in the range of 0.07 to 0.8 mg/l, 0.002 to 0.06 mg/l, 0.01 to 0.8 mg/l, 0.08 to 0.18 mg/l, and 0.003 to 0.27 mg/l, respectively. In general, the lead and cadmium content was higher than other metals in some of the investigated edible vegetable oils. Most values fell within the permissible quality limits for edibility as prescribed by the World Health Organization (WHO) and the National Agency for Food and Drug Administration and Control (NAFDAC). However, the levels of Pb and Cd exceeded the reference levels in some locally produced vegetable oils. CONCLUSION: To address the exceeded levels of heavy metals, it is imperative to implement more careful handling, processing of raw materials, and filtering practices. Producers and marketers should take the necessary precautions to prevent contamination. Strict regulatory control from responsible bodies and stakeholders is recommended to ensure the safety and metal contents of vegetable oils originating from the study area.
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Metais Pesados , Óleos de Plantas , Metais Pesados/análise , Etiópia , Óleos de Plantas/química , Estudos Transversais , Humanos , Minerais/análise , Espectrofotometria Atômica , Contaminação de Alimentos/análiseRESUMO
Microbial fuel cells (MFCs) have been recently proven to synthesise biosurfactants from waste products. In classic bioreactors, the efficiency of biosynthesis process can be controlled by the concentration of nitrogen content in the electrolyte. However, it was not known whether a similar control mechanism could be applied in current-generating conditions. In this work, the effect of nitrogen concentration on biosurfactant production from waste cooking oil was investigated. The concentration of NH4Cl in the electrolyte ranged from 0 to 1 g L-1. The maximum power density equal to 17.5 W m-3 was achieved at a concentration of 0.5 g L-1 (C/N = 2.32) and was accompanied by the highest surface tension decrease (to 54.6 mN m-1) and an emulsification activity index of 95.4%. Characterisation of the biosurfactants produced by the LC-MS/MS method showed the presence of eleven compounds belonging to the mono- and di-rhamnolipids group, most likely produced by P. aeruginosa, which was the most abundant (19.6%) in the community. Importantly, we have found a strong correlation (R = -0.96) of power and biosurfactant activity in response to C/N ratio. This study shows that nitrogen plays an important role in the current-generating metabolism of waste cooking oil. To the best of our knowledge, this is the first study where the nitrogen optimisation was investigated to improve the synthesis of biosurfactants and power generation in a bioelectrochemical system.
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Fontes de Energia Bioelétrica , Glicolipídeos , Nitrogênio , Tensoativos , Nitrogênio/metabolismo , Tensoativos/metabolismo , Glicolipídeos/metabolismo , Eletrodos , Reatores BiológicosRESUMO
The use of vegetable oil-dervied plasticizers to enhance the flexibility of polylactic acid (PLA) has received much attention due to their renewability, inexpensiveness and biodegradation. However, the double bonds in vegetable oil-based plasticizers limit their compatibility with PLA, resulting in PLA-derived products with reduced flexibility. Herein, we examined soybean oil-derived hydrogenated dimer acid-based polyethylene glycol methyl ether esters (HDA-2n, 2n = 2, 4, 6 or 8, referring to the ethoxy units) developed via the direct esterification of saturated hydrogenated dimer acid and polyethylene glycol monomethyl ethers. The resulting HDA-2n was first used as a plasticizer for PLA, and the effects of the ethoxy units in HDA-2n on the overall performance of the plasticized PLA were systematically investigated. The results showed that, compared with PLA blended with dioctyl terephthalate (DOTP), the PLA plasticized by HDA-8 with the maximum number of ethoxy units (PLA/HDA-8) exhibited better low-temperature resistance (40.1 °C vs. 15.3 °C), thermal stability (246.8 °C vs. 327.6 °C) and gas barrier properties. Additionally, the biodegradation results showed that HDA-8 could be biodegraded by directly burying it in soil. All results suggest that HDA-8 could be used as green alternative to the traditional petroleum-based plasticizer DOTP, which is applied in the PLA industry.
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Industrial activities contribute to environmental pollution, particularly through unregulated effluent discharges, causing adverse effects on ecosystems. Vegetable oils, as insoluble substances, exacerbate this pollution, forming impermeable films and affecting the oxygen transfer, leading to serious habitat disruption. Organic wastes, such as soybean texturized waste, spent mushroom substrate, and stabilized poultry litter, were assessed for their efficacy in enhancing the degradation of vegetable oil in contaminated soil. For this purpose, contaminated soil was amended with each of the wastes (10% w/w) using microcosm systems, which were monitored physico-chemically, microbiologically and toxicologically. Results indicate that the wastes promoted significant oil degradation, achieving 83.1, 90.7, and 86.2% removal for soybean texturized waste, spent mushroom substrate, and stabilized poultry litter, respectively, within a 90-day period. Additionally, they positively influenced soil microbial activity, as evidenced by increased levels of culturable microorganisms and hydrolytic microbial activity. While bioassays indicated no phytotoxicity in most cases, soybean texturized waste exhibited inhibitory effects on seed germination and root elongation of Lactuca sativa. This study significantly enhances our comprehension of remediation techniques for sites tainted with vegetable oils, highlighting the critical role of organic waste as eco-friendly agents in soil restoration. Emphasizing the practical implications of these findings is imperative to underscore the relevance and urgency of addressing vegetable oil contamination in soil. Moving forward, tailored strategies considering both contaminant characteristics and soil ecosystem traits are vital for ensuring effective and sustainable soil remediation.
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Biodegradação Ambiental , Glycine max , Óleos de Plantas , Aves Domésticas , Microbiologia do Solo , Poluentes do Solo , Solo , Animais , Poluentes do Solo/metabolismo , Glycine max/crescimento & desenvolvimento , Glycine max/microbiologia , Óleos de Plantas/metabolismo , Solo/química , Agaricales/metabolismo , Agaricales/crescimento & desenvolvimento , Lactuca/crescimento & desenvolvimento , Bactérias/metabolismo , Germinação/efeitos dos fármacos , Resíduos IndustriaisRESUMO
Edible oils are imported and produced in Ethiopia, notably in Gondar, and their production has expanded considerably in recent years. The expansion of locally produced edible vegetable oils with severe quality control, substandard edible oil production, and quality deterioration may contribute to the contamination of microbes, which may cause public health problems. This study determines the microbiological quality of edible vegetable oils being produced and marketed in Gondar City, Northwest Ethiopia, in 2021. A laboratory-based cross-sectional study design was conducted from May to July 2021 in Gondar City. A simple random sampling technique was used to collect 17 edible vegetable oil samples. Aseptically collected samples were analyzed in the microbiology lab room. The microbiological quality of vegetable oil was assessed using standard microbiological procedures and techniques. The collected data were entered into a Microsoft Excel 2016 spreadsheet and Stata Version 14. A non-parametric Kruskal-Wallis test was used to assess significant variation. Seventeen edible vegetable oil samples were examined and found to contain a varying number of bacteria, yeast, and molds. Staphylococcus aureus, Klebsiella Pneumoniae, and Pseudomonas aeruginosa were the identified bacteria, whereas Saccharomyces cerevisiae, Aspergillus niger, Aspergillus flavus, and Aspergillus fumigatus were the identified fungi. Total coliform and fecal coliform isolates were also identified in the oil samples. A level of microbial contamination that has public health importance was observed in some of the oil samples analyzed, and the isolated microorganisms indicate unhygienic handling, processing, and storage practices in the oil production and market sites. The introduction of strict rules, regulations, and updated manufacturing technologies and processes to ensure food safety and quality is needed.
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Bactérias , Óleos de Plantas , Etiópia , Bactérias/isolamento & purificação , Bactérias/classificação , Fungos , Microbiologia de Alimentos , Estudos Transversais , Contaminação de Alimentos/análise , CidadesRESUMO
This systematic review and meta-analysis quantified the effects of various vegetable oil-based nanoemulsion (NE) formulations on muscle foods' microbial and chemical quality by estimating the weighted overall response ratio (R*). Treatment of muscle foods with NE formulations reduced the growth rates of total mesophilic bacteria, total psychrophilic bacteria, lactic acid bacteria, and Enterobacteriaceae by 26.2% (R*=0.738), 19% (R*=0.810), 44.7% (R*=0.553), and 31.8% (R*=0.682) during the storage period, respectively. Moreover, the NE formulations retarded the increasing rates of volatile basic-nitrogen content, lipid and protein oxidation, and lipid hydrolysis by 41.4% (R*=0.586), 34% (R*=0.660), 55% (R*=0.450), and 37.1% (R*=0.629), respectively. The NE formulations prepared from safflower, olive, canola, and sunflower oil were more effective than the other vegetable oils to control microbial growth and slow down chemical changes in muscle foods. The combination of nanoemulsions (NEs) and essential oils (EOs) was more efficient than NEs to preserve muscle foods. Packaging NE-treated muscle foods under anaerobic conditions provided better control of microbial growth and chemical changes than packaging under aerobic conditions. Consequently, a combination of vegetable oil-based NEs and EOs followed by anaerobic packaging is the most effective treatment to improve the quality of muscle foods.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2057415 .
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Óleos Voláteis , Óleos de Plantas , Óleos de Plantas/química , Óleos Voláteis/farmacologia , Músculos , Alimentos , Conservação de AlimentosRESUMO
Vegetable oils and fatty acid esters (FAEs) are commonly used in various industrial and commercial applications. However, the presence of contaminants in these oils can severely affect their functionality and suitability. Conventional refining techniques for vegetable oils typically involve degumming, neutralization, bleaching and deodorization. Meanwhile, refining of FAEs often utilize wet or dry washing processes. These are often resource-intensive, producing substantial waste products, causing neutral oil loss, and can also result in the loss of micronutrients. To address these challenges, researchers have explored the use of nano-adsorbents and electrostatic field (E-field) technologies as alternatives in purifying industrial dielectric oils by removing polar particles and contaminants. Nano-adsorbents demonstrated increased efficiency in removing polar contamination while minimizing neutral oil loss. However, removal of these spent adsorbents can be challenging due to their nano-size, and physicochemical properties. The use of these materials combined with E-field technologies offers a novel and sustainable solution for removing spent nano-adsorbents and contaminants. This review provides an overview of current traditional and novel refining technologies for vegetable oils and FAEs, including their associated limitations. Compared to conventional methods, E-field treatment offers several advantages, making it an attractive alternative to conventional approaches in food processing and oil refining.
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To promote the application of time-resolved fluorescence in oxidation determination of edible vegetable oil, fluorescence lifetime of chlorophyll α in oxidized edible vegetable oils was recorded and analyzed by simulated microenvironment experiments and spectral methods. It was showed that fluorescence lifetime of chlorophyll α decreased with the increase of polarity in the early stage of oxidation, and increased with the increase of viscosity in the later stage of oxidation. Conjugation effect and hydrogen bonding existed in the microenvironment of oxidized edible vegetable oil were considered to be the factors leading to the increase of fluorescence lifetime. The change mechanism of fluorescence lifetime in oxidized edible vegetable oil was supplied, which was considered to be strong support for the application of time-resolved fluorescence.
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Countercurrent chromatography (CCC) is a preparative instrumental method where both the mobile and stationary phases are liquids and which are predominantly used for the isolation of natural products. In this study, we widened the scope of CCC by using it as an instrumental method for the direct enrichment of the free sterol fraction from plant oils to which they contribute with ~ 1%. For the enrichment of sterols in a narrow band, we employed the so-called co-current CCC (ccCCC) mode in which both liquid phases of the solvent system (here: n-hexane/ethanol/methanol/water (34:11:12:2, v/v/v/v)) are moved at different flow rates in the same direction. Different from previous applications of ccCCC, the lower and predominant "stationary" phase (LPs) was pumped twice as fast as the mobile upper phase (UPm). This novel reversed ccCCC mode improved the performance but also required a higher demand of LPs compared to UPm. Therefore, the exact phase composition of UPm and LPs was determined by gas chromatography and Karl Fischer titration. This step enabled the direct preparation of LPs which considerably reduced the waste of solvents. Internal standards (phenyl-substituted fatty acid alkyl esters) were synthesised and utilised to frame the free sterol fraction. This approach allowed a fractionation of free sterols based on the UV signal and compensated run-to-run variations. The reversed ccCCC method was then applied to the sample preparation of five vegetable oils. In addition to free sterols, free tocochromanols (tocopherols, vitamin E) were also eluted in the same fraction as free sterols.
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This work reports on the synthesis of statistical copolymers of bio-based PA 6.19 and PA 6.6 together with the production of melt-spun monofilaments for the production of sustainable textile fibers. The plant oil-based 1.19-nonadecanedioic acid is synthesized from bio-derived oleic acid via isomerizing methoxycarbonylation. The homopolymer PA 6.19 with a carbon-based bio-content of 72% shows a good elongation at break of 166%, but lower tensile strength than commercial PA 6 (43 MPa versus 82 MPa). Addition of adipic acid to form statistical PA 6.6/6.19 copolymers improves toughness while maintaining the high elongation at break. Two PA 6.6/6.19 copolymers with a carbon-based bio-content of 26% and 33% are successfully synthesized and exhibited comparable toughness (94 ± 6 MPa and 92 ± 2 MPa) to the commercial PA 6 (92 ± 15 MPa). The bio-based copolymers also exhibit a much lower water uptake than PA 6 and PA 6.6, resulting in a higher dimensional stability. Melt spinning of the oleic acid-based polyamides is successfully carried out to produce monofilaments with sufficient properties for further processing in a knitting process, demonstrating the capabilities of the bio-based PA 6.6/6.19 copolymers for use in the textile industry.
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Ácido Oleico , Polímeros , Resistência à Tração , Nylons , CarbonoRESUMO
To date, the development of renewable fuels has become a normal phenomenon to solve the problem of diesel fuel emissions and the scarcity of fossil fuels. Biodiesel production has some limitations, such as two-step processes requiring high free fatty acids (FFAs), oil feedstocks and gum formation. Hydrotreated vegetable oil (HVO) is a newly developed international renewable diesel that uses renewable feedstocks via the hydrotreatment process. Unlike FAME, FFAs percentage doesn't affect the HVO production and sustains a higher yield. The improved characteristics of HVO, such as a higher cetane value, better cold flow properties, lower emissions and excellent oxidation stability for storage, stand out from FAME biodiesel. Moreover, HVO is a hydrocarbon without oxygen content, but FAME is an ester with 11% oxygen content which makes it differ in oxidation stability. Waste sludge palm oil (SPO), an abundant non-edible industrial waste, was reused and selected as the feedstock for HVO production. Techno-economical and energy analyses were conducted for HVO production using Aspen HYSYS with a plant capacity of 25,000 kg/h. Alternatively, hydrogen has been recycled to reduce the hydrogen feed. With a capital investment of RM 65.86 million and an annual production cost of RM 332.56 million, the base case of the SPO-HVO production process was more desirable after consideration of all economic indicators and HVO purity. The base case of SPO-HVO production could achieve a return on investment (ROI) of 89.03% with a payback period (PBP) of 1.68 years. The SPO-HVO production in this study has observed a reduction in the primary greenhouse gas, carbon dioxide (CO2) emission by up to 90% and the total annual production cost by nearly RM 450 million. Therefore, SPO-HVO production is a potential and alternative process to produce biobased diesel fuels with waste oil.
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Óleos de Plantas , Esgotos , Óleo de Palmeira , Emissões de Veículos , Biocombustíveis/análise , Gasolina/análise , Hidrogênio , OxigênioRESUMO
Green extraction methods using a combination of mechanical, enzymatic, and green chemical treatments were evaluated for the sequential extraction of carotenoid pigments, protein, and chitin from crab processing discards. Key objectives included avoiding the use of hazardous chemical solvents, conducting as close to a 100% green extraction as possible, and developing simple processes to facilitate implementation into processing plants without the need for complicated and expensive equipment. Three crab bio-products were obtained: pigmented vegetable oil, pigmented protein powder, and chitin. Carotenoid extractions were performed using vegetable oils (corn, canola, and sunflower oils), giving between 24.85% and 37.93% astaxanthin recovery. Citric acid was used to demineralize the remaining material and afforded a pigmented protein powder. Three different proteases were used to deproteinate and isolate chitin in yields between 17.06% and 19.15%. The chitin was still highly colored and therefore decolorization was attempted using hydrogen peroxide. Characterization studies were conducted on each of the crab bio-products isolated including powder X-ray diffraction analysis on the chitin (80.18% crystallinity index, CI, achieved using green methods). Overall, three valuable bio-products could be obtained but further research is needed to obtain pigment-free chitin in an environmentally friendly manner.
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Braquiúros , Animais , Braquiúros/química , Pós , Proteínas , Peptídeo Hidrolases , Quitina/químicaRESUMO
The molecular characteristics and tissue disruption of 10 fatty acid-binding protein (fabp) genes in gilthead seabream (Sparus aurata) were investigated, and their expression levels were found in the fish fed diets with different vegetable oil (VO) sources, which may explore the potential function of fabp genes in S. aurata. For this purpose, the open reading frames of fabp genes involved in the transport and ß-oxidation of fatty acids (FA) were molecularly cloned and characterized. S. aurata was then exposed to a two-staged feeding trial (the grow-out period following a wash-out period) at low water temperatures. In the grow-out period, the fish were fed diets containing 50% and 100% ratios of various VOs for 60 days, and in the wash-out period, the fish were fed a diet containing 100% fish oil (FO) for 30 days. It has been determined that (a) S. aurata and vertebrate fabp/FABP genes are orthologues; (b) spatio-temporal differences in tissue-specific patterns of fabp genes differ importantly; for instance, the difference between the highest and lowest values reaches 13 × 105 -fold in the fabp10a; and (c) VO-based diets upregulated fabp transcript levels in the liver and muscle with some exceptions, such as liver fabp11a and muscle fabp7a. Gene expressions of only the hepatic fabp7b and fabp10a genes were diminished at the end of the wash-out period. In this study, the authors provide further evidence that dietary FAs affect fabp mRNA expressions in S. aurata. This might be useful in the nutritional control of fabp genes to maintain lipid homeostasis in marine fish fed VO-based diets at low water temperatures.
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Dourada , Animais , Dourada/genética , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Temperatura , Ácidos Graxos/metabolismo , Clonagem Molecular , Dieta/veterináriaRESUMO
In the present study a sequential process composed of electrocoagulation (EC) followed by electrooxidation (EO) was utilized at the laboratory scale to remove the chemical oxygen demand (COD) from wastewater generated in Iraqi vegetable oil refinery plant.in the EC, impacts of operating variables such as current density (10-30 mA cm-2) and pH (4-10),and EC time (30-90 min) on the COD removal (RE%) were investigated using response surface methodology (RSM) based on Box- Behnken design(BBD). a mathematical correlation that relates the operating factors with RE% was developed and its regression coefficient was 99.02% confirming the significant of the model. Response surface plots showed that RE% increased with increasing current density and time while it decreased with increasing pH. The optimum removal with a lower cost for EC process were achieved at current density of 30mA/cm2, pH of 4, and electrolysis time of 90 min in which RE% of 69.19% was obtained with requirement of 0.513kWh/kg COD as specific energy consumption (SEC). The effluent exit from EC was treated by EO for a period of 240min at a current density of 30mA/cm2 and an initial pH value of 4 to obtain RE% of 96% at SEC of 1.554 kWh/kg COD. Combining EC with EO resulted in a total RE% of 98.72% and a total SEC of 2.067 kWh/kg COD. Based on the results of present study, the applicability of a sequential electrocoagulation-electrooxidation process for treatment vegetable oil wastewaters is feasible.
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Eliminação de Resíduos Líquidos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Verduras , Eletrocoagulação/métodos , Óleos de PlantasRESUMO
Because of its application potential and biodegradability, poly(3-hydroxybutyrate-co-3-hydroxyvalerate;PHBV), a member of the polyhydroxyalkanoates (PHA) biopolymer family, is one of the most extensively studied PHA. High PHBV productivity with a significant amount of hydroxyvalerate (HV) content is very appealing for commercial scale production. The goal of this study was to investigate the efficiency of various defined limitation strategies, namely nitrogen, phosphorus, and oxygen-limitation, for high yield PHBV production by Cupriavidus necator H16 with increased HV unit using waste frying vegetable oil (WFO) and propionic acid (PA) in a high cell density culture (5 L bioreactor). With optimized WFO and PA feeding, highest PHBV harvest (121.7 ± 2.59 g/L; HV 13.9 ± 0.44% (w/w)) and volumetric productivity (2.03 ± 0.04 gPHBV/L·h) were obtained in oxygen-limited operation, while highest HV content (19.8 ± 0.28 wt%) and yield coefficient (0.43 ± 0.017 gHV/gPA) were observed during phosphorus-limited cultivation. Although nitrogen limitation is widely applied in the production of PHA, nitrogen-limited cultivation had the lowest cell dry matter, PHBV production, volumetric productivity, oil-to-HB and PA-to-HV yield coefficients for the given conditions. The results of the present study demonstrate the highest PHBV yield together with the highest HV content using WFO as main carbon source and PA as the HV precursor ever reported in the literature.
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate;PHBV), a member of the polyhydroxyalkanoates (PHA) biopolymer family, is one of the most extensively studied PHA due to its high application potential and biodegradability properties. High PHBV productivity with substantial amount of hydroxyvalerate (HV) content is of great interest for commercial scale PHA production to compete with conventional plastic costs.In this study, we investigated the effectiveness of different nutrient limitation strategies in optimizing the production of PHBV from waste frying vegetable oil and propionic acid. Although there are individual studies investigating the performance of operational PHBV production strategies such as nitrogen, phosphorus, or oxygen limitation, none of them have comprehensively compared the effect of different limitation strategies on PHA production parameters using waste frying vegetable oil as the main carbon source and propionic acid as the cheapest HV precursor. To our knowledge, this is the first study that evaluates the impact of these three limitation strategies on the efficient production of PHBV from waste frying oil and propionic acid in high cell density fermentations of Cupriavidus necator H16. The results demonstrate the highest PHBV yield together with the highest HV content using waste frying oil as main carbon source and propionic acid as the cheapest HV precursor ever reported in the literature. In addition, it is shown that the PHBV yield and its HV content could be intercorrelated by switching between oxygen and phosphorus-limited strategies for desired material specifications.
Assuntos
Cupriavidus necator , Poli-Hidroxialcanoatos , Poliésteres , Fermentação , Cupriavidus necator/metabolismo , Hidroxibutiratos , NitrogênioRESUMO
Insulating oil plays a crucial role in internal insulation of oil-impregnated transformers. It has been demonstrated in a variety of experimental studies that mineral oil (MO) and vegetable oil (VO) can be blended in different ratios to improve insulation properties; however, the mechanisms underlying this phenomenon remain unclear. In this study, a molecular dynamics (MD) simulation approach was used to investigate diffusion of water molecules in VO/MO blends and dielectric constants of a mixture. The results show that the diffusion coefficient of water molecules is negatively correlated with the proportion of VO; thus, addition of VO helps to improve the insulation properties of a mixture. Due to introduction of strong polar functional groups, a decrease in the diffusion behavior of water molecules can be attributed to an increase in the interaction energy and formation of hydrogen bonds between water molecules and the mixed oil system. There is a direct correlation between the dielectric constant of a mixture and VO content; however, it is very sensitive to water content. The presence of strong polar water molecules or functional groups in a mixture leads to an increase in the dielectric constant, which results in a reduction in insulating properties. Accordingly, presence of polar groups plays an important role in determining the insulating properties of a mixture. To increase the insulation performance of a mixture, it is important to consider the diffusion-inhibiting and dielectric effects of the stronger polar groups in vegetable oil compared to those in mineral oil.