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1.
为了有效提高苍耳子油的提取效率,考察了提取溶剂和提取方法对其提取率的影响.在5种常用提取溶剂(乙醇、乙酸乙酯、丙酮、二氯甲烷和环己烷)中,采用索氏提取法时二氯甲烷的提取率最高,采用微波法时乙醇的提取率最高.另外,采用微波法提取的苍耳子油的得率略低于索氏提取法,但微波法的提取效率更高,提取时间节省近30倍,溶剂消耗节省2倍.综合考虑,微波法提取具有更大的优势.  相似文献   

2.
The effect of different processing methods namely enzymatic method using crude protease extract (CPE) from overripe pineapple, microwave‐assisted extraction (MAE) and ultrasound‐assisted extraction (UAE) methods on the recovery yield of virgin coconut oil (VCO) is evaluated. The physicochemical properties of VCOs namely color, iodine value (IV), refractive index, saponification value, moisture content, free fatty acid, p‐anisidine value, lipid peroxidation, fatty acid composition, triacylglycerol (TAG) composition, melting and crystallization profile are compared. The total phenolic compounds and scavenging activity of the extracted VCOs are also examined. Results reveal that enzymatic approach exhibits the highest VCO yield (77.7% ± 0.38) at 50 °C for 2 h, followed by MAE (58.6%±0.07), control without enzyme (24.1%±0.19) and UAE (24.1%±0.12). The physicochemical properties of the VCOs extracted are found to conform to APCC standards established except IV. The antioxidant activity of VCO extracted with CPE shows no significant difference with MAE and UAE methods (p > 0.05). Lauric acid appears to be the most abundant fatty acid detected in all VCO samples. Similar exotherms and endotherms are observed in both melting and crystallization profiles with two distinct peaks exhibited. The TAG compositions of the extracted VCOs are mainly LaLaLa, LaLaM, CLaLa, CCLa, and LaMM (C = Capric acid; La = Lauric acid; M = Myristic acid). Practical Applications: The results obtained from this study indicate that VCO extraction using CPE from overripe pineapple is feasible. The enzymatic extraction protocol presented here would be useful for VCO production at industrial scale with a promising oil yield.  相似文献   

3.
Oil from coffee silverskin (CS) is a potential source of fatty acids with promising applications in several industries. Thus, CS crude oil extraction processes were investigated for further enzymatic hydrolysis for fatty acids production. Firstly, Soxhlet (with 150 mL hexane for 8 hours at 70 °C) and ultrasound-assisted (three times in sequential with 50 mL of hexane for 30 min at 30 °C) extractions were carried out to extract CS oil (3.8% and 3.1%, respectively). The fatty acid profiles obtained by both extraction methods presented a similar composition, shows palmitic (16:0: 32.6–34.4%) and linoleic acids (18:2: 31.5–36.1%) as the main. Then, CS oil extracted by Soxhlet was used as the feedstock for fatty acids production by enzymatic hydrolysis using four commercial lipases. Among the lipases studied, Candida rugosa lipase (CRL) displayed a higher hydrolytic activity (1143.70 U g−1), with a maximum hydrolysis degree of 51.94% (acid value of the CS oil increased from 13.4 to 37.5 mg KOH g−1) after 180 min of reaction. Molecular docking analysis showed that interactions between the CRL active site (Ser209 and His449) and palmitic acid, the fatty acid of highest concentration in CS oil (≈35%), lead to higher hydrolytic activity. The integrated process developed is an advance in fatty acid production and valorization of coffee industry waste, since there is still a promising approach yet to be explored that aims at the utilization of residual CS oil.  相似文献   

4.
5.
Roman nettle (Urtica pilulifera L.) is an annual plant whose seeds are rich in oil and valuable phytochemicals. In this study, oil from Roman nettle seeds is extracted by cold pressing and its quality is evaluated during storage at room temperature for up to 90 days. The seed moisture content is adjusted to 0%, 2.5%, 5%, 7.5%, and 10% (g 100 g−1) to evaluate its effect on oil extraction yield. The highest oil yield (31.5%) is found in the seeds containing 5% moisture. Acid and peroxide values increase with both moisture content increase and during storage. Moreover, an increase in seed moisture content decreases the oxidative stability (from 8.1 to 6.3 h), carotenoids (from 25 to 14 mg kg−1), chlorophylls (from 742 to 486 mg kg−1), and phenolic contents (from 134 to 97 (mg caffeic acid per kg oil)) of the extracted oils. Fatty acid profile and phytosterols are not significantly influenced (p > 0.05) by the moisture content of the seeds and storage. Total phenol contents and γ-tocopherol levels increase during storage, but carotenoids, chlorophylls, and α-tocopherol levels decrease. Based on overall composition and quality parameters, Roman nettle seed oil may have potential food applications.  相似文献   

6.
The aim of the presented study is to examine the physicochemical parameters of the lipids present in Lupinus mutabilis seed and to compare the results with the available data for other commonly used vegetable oils. The oil quality indexes, oxidative stability index (OSI), and melting characteristics are examined. Andean lupin oil has remarkably high oxidative stability (OSI = 65 h) comparable to high-oleic oils counterparts. Quality parameters meet commonly accepted standards, including peroxide value (3.95 meq O2 kg−1) and p-anisidine value (1.25). The acid number value is 1.85 mg KOH g−1. The iodine value is 110.27 g/100 g, while the enthalpy required to increase the temperature of the sample from −60 to 80 °C is equal to 57.41 kJ kg−1. The beginning of the melting event (Tonset) and the phase transition temperature (Tpeak) values for L. mutabilis seed oil are −29.46 and −22.63 °C, respectively. The presented results indicate the unusually high oxidative stability of the oil obtained from L. mutabilis seeds, which opens up a whole spectrum of application possibilities, e.g., designing blends with other commonly used vegetable oils to enhance their low stability. Practical Applications: The presented results provide insight into physicochemical parameters of the lipid fraction isolated from Lupinus mutabilis seeds. Andean lupin oil has very high oxidative stability, comparable to high-oleic rapeseed and sunflower oils. Therefore, the identified potential use of the studied oils is, e.g. an additive that can increase the stability of commercial vegetable oils characterized by much lower oxidative stability.  相似文献   

7.
Phytosterols of manketti (Schinziophyton rautanenii) nut oil extracted by Soxhlet, mechanical shaking using hexane, screw press and supercritical carbon dioxide, were analyzed by gas chromatography with flame ionization detection and identified by gas chromatography–mass spectrometry. The presence of several phytosterols (campesterol, stigmasterol, β‐sitosterol, Δ5‐avenasterol, 22‐dihydrospinasterol and Δ7‐avenasterol) previously reported in manketti oil, was confirmed. In addition, another fourteen phytosterols (lanosterol, Δ5,23‐stigmastadienol, Δ7‐campesterol, clerosterol, obtusifoliol, Δ5,24(25)‐stigmastadienol, α‐amyrin, gramisterol, cycloeucalenol, cycloartenol, stigmasta‐8,24‐dienol‐3‐β‐ol, 28‐methylobtusifoliol, 24‐methylenecycloartenol and citrostadienol) were identified. The phytosterols, β‐sitosterol, Δ5‐avenasterol and campesterol, had the highest concentrations in oils extracted by all the methods, whereas stigmasterol and cycloartenol were abundant in oils extracted by mechanical shaking and supercritical carbon dioxide. Total phytosterols and the quantities of individual phytosterols differed significantly (p ≤ 0.05) in oils from the four extraction methods. Mechanical shaking extracted the highest levels of total sterols (22,100 mg/100 g oil), followed by supercritical fluid extraction (9,550 mg/100 g oil). Screw press and Soxhlet extracted oils contained the lowest levels of total sterols, 3,810 mg/100 g oil and 3,350 mg/100 g oil, respectively.  相似文献   

8.
This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction (MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed (S/F, ml of solvent to gram of feed) ratios. The process parameters were optimized by statistical approach using historical data design of response surface method (RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield.  相似文献   

9.
The study investigates the impact of operating parameters such as temperature (90, 100, 110, 120 °C), airflow rate (10, 15, 20 L h−1), and sample weight (3, 6, 9 g) on the oxidative stability of cold-pressed camelina and hemp seed oils using the Rancimat apparatus. Conducted analysis indicates a significant influence of temperature on oils' induction time. Moreover, higher airflows should be selected at high analysis temperatures. Based on the calculated parameters of the oxidation kinetics, it was shown that hemp oil has higher activation energy values than camelina oil. Response surface methodology (RSM) indicates that to minimize the determination time of camelina oil oxidation, the following analysis conditions should be selected: sample weight (SW) = 33.5 g, airflow (AF) = 20 L h−1, and temperature (T) = 120 °C. However, for hemp oil, these parameters should be SW = 5.56 g, AF = 15 L h−1, T = 120 °C. Sample mass does not significantly impact oils induction time, which depends mainly on the temperature and airflow. Practical applications: The conducted research shows that the parameters of the cold-pressed camelina and hemp oils oxidative stability have to be determined experimentally. The determined parameters for assessing the oxidative stability will reduce the analysis time and the possibility of interpolating the obtained result at different temperatures and analysis parameters.  相似文献   

10.
Crude oil was extracted from cottonseed by three different methods to study the influence of extraction technique on the free fatty acid (FFA) concentration. Extraction procedures that recovered more oil had higher levels of FFA. In addition, the highest concentration of FFA was found in oil recovered by Soxhlet reextraction of a meal initially defatted by a room-temperature extraction process. The FFA concentrations of oils recovered by Soxhlet extraction were highly correlated with the FFA concentration of oils recovered by the other extraction methods studied (R 2>0.96). Titration of oil and gas chromatography of silylated oil were compared as methods to determine FFA concentration. The methods compared well (R 2=0.998) with the titration method, giving ∼5% higher values for FFA than the chromatography method. Half of this difference appeared to be due to the oleic acid approximation used in the titration approach. The other half of the difference is likely due to the detection of other acidic components in crude oil.  相似文献   

11.
Photobacteriosis is a septicaemic bacterial disease affecting several marine species around the globe, resulting in significant economic losses. Although many studies have been performed related to the pathogen virulence and resistance factors, information regarding the host defence mechanisms activated once an infection takes place is still scarce. The present study was designed to understand innate immune responses of farmed juvenile gilthead seabream (Sparus aurata) after Photobacterium damselae subsp. piscicida (Phdp) infection. Therefore, two groups of seabream juveniles were intraperitoneally injected with 100 µL of PBS (placebo) or 100 µL of exponentially growing Phdp (1 × 106 CFU/mL; infected). The blood, plasma, liver, and head kidney of six fish from each treatment were sampled immediately before infection and 3, 6, 9, 24 and 48 h after infection for the broad screening of fish immune and oxidative stress responses. Infected animals presented marked anaemia, neutrophilia and monocytosis, conditions that are correlated with an increased expression of genes related to inflammation and phagocytic activity. Similar studies with different fish species and bacteria can be useful for the definition of health biomarkers that might help fish farmers to prevent the occurrence of such diseases.  相似文献   

12.
For complete utilization of raw materials and edible oil production, the oil from golden melon seeds (GSs) is extracted via the cold-pressing, hot-pressing, and ultrasound-assisted aqueous enzymatic extraction (AEE), and the fatty acid composition, and nutritional value of the extracted GS oils (GSOs) are analyzed. The volatile compounds present in the GSOs are determined using gas chromatography–mass spectrometry. The aroma profiles of different GSO samples are further distinguished by using an electronic nose. A total of 16 fatty acids are identified in the GSO samples, with atherogenic, thrombogenic, and nutritive value indices ranging from 0.142–0.151, 0.366–0.403, and 5.019–5.299, respectively. Moreover, 43 volatile compounds, including esters, hydrocarbons, alcohols, ketones, pyrazines, and aldehydes are identified. The cold-pressed GSO presents fresh and fruity flavors, while the hot-pressed GSO presents roasted, nutty, fatty, and fruity flavors, and the GSO obtained via AEE presents fatty and fruity flavors. The acid and peroxide contents of these oil samples are 0.69–079 mg g−1 and 5.17–5.79 mmol kg−1, respectively. The results indicate that the extraction method affects the fatty acid composition, flavor components, and physiochemical properties of the GSO. This study may help promote the development of edible GSO. Practical applications: With high demand for edible oils, it is of great significance to find natural edible oils from different sources. The oil in golden melon seeds is extracted by different methods. Their fatty acid composition and flavor components are analyzed. The GSO extracted via AEE method is rich in fatty acids composition. This work would guide the development of an edible GSO and increase the value of golden melon.  相似文献   

13.
Freezing is an efficient method of fish preservation. The aim of the present work was to examine the impact of freezing in fatty acid composition and in the in vitro inhibitory activity of sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) fillet lipids against platelet activating factor (PAF). The Bligh and Dyer extraction method and the counter‐current distribution method were used to obtain total, polar and neutral lipids. The fatty acid analysis conducted using the internal standard method and the biological assay on washed rabbit platelets took place calculating the in vitro inhibitory activity of fish lipids against 2.5 × 10?11 M of PAF. No statistical changes (p<0.05) occurred in fatty acid content of fresh and thawed gilthead sea bream, while fatty acid amount in thawed sea bass was significantly higher (p<0.05) compared to fresh fish. Total lipids of both thawed fish species exhibited stronger anti‐thrombotic activity compared to fresh fish. Freezing preserved fish quality and reinforced the anti‐thrombotic properties of fish oils, since even after 6 months of freezing, fish oils preserve their nutritional value in terms of protecting against cardiovascular diseases. Practical applications: Fish fillets contain high amount of unsaturated lipids that may easily undergo lipid oxidation. Freezing and frozen storage prevent such oxidative changes so fish quality is retained. Fatty acids and PAF‐antagonists in fish are of major importance since they contribute to the nutritional value of fish. The practical application of this work lies on the evaluation of the nutritional value of fish in terms of cardio protection by examining the impact of freezing on the levels of fatty acids and PAF‐antagonists in aquacultured fish fillets.  相似文献   

14.
The effect of the proportion of ‘Hass’ avocado skin tissue present during aqueous cold pressed avocado oil extraction on the pigment concentration and oil quality was determined. Increasing amounts of skin (i.e., from 0 to 100% of available skin) were included with the flesh before grinding and malaxing in a laboratory-scale cold pressed extraction process. The recovered oils were analyzed for oil quality and color. The pigment concentrations in the oil were determined by high performance liquid chromatography (HPLC). With increasing amounts of skin addition, there was an increase in the green color, as indicated by hue angle, of the avocado oils. There were also increased concentrations of carotenoids and chlorophylls in the oil as the proportion of skin during malaxing was increased. The lutein concentration in the oils increased from 1.13 to 3.21 μg g−1 as the amount of skin added to the malaxer increased from 0 to 100% skin, and the total chlorophyll concentration in the same oils increased from 7.3 to 27.5 μg g−1. The green color of cold pressed avocado oil and the pigment concentrations can be increased by adding more skin to the malaxer during oil extraction.  相似文献   

15.
The physicochemical properties of crude Nigella seed (Nigella sativa L.) oil which was extracted using Soxhlet, Modified Bligh–Dyer and Hexane extraction methods were determined. The effect of different extraction methods which includes different parameters, such as temperature, time and solvent on the extraction yield and the physicochemical properties were investigated. The experimental results showed that temperature, different solvents and extraction time had the most significant effect on the yield of the Nigella oil extracts. The fatty acid (FA) compositions of Nigella seed oil were further analyzed by gas chromatography to compare the extraction methods. The C16:0, C18:1 and C18:2 have been identified to be the dominant fatty acids in the Nigella seed oils. However, the main triacylglycerol (TAG) was LLL followed by OLL and PLL. The FA and TAG content showed that the composition of the Nigella seed oil extracted by different methods was mostly similar, whereas relative concentration of the identified compounds were apparently different according to the extraction methods. The melting and crystallization temperatures of the oil extracted by Soxhlet were −2.54 and −55.76 °C, respectively. The general characteristics of the Nigella seed oil obtained by different extraction methods were further compared. Where the Soxhlet extraction method was considered to be the optimum process for extracting Nigella seed oil with a higher quality with respect to the other two processes.  相似文献   

16.
Historically, gilthead seabream (Sparus aurata) has been considered a fish species resistant to nervous necrosis virus (NNV) disease. Nevertheless, mortality in seabream hatcheries, associated with typical clinical signs of the viral encephalopathy and retinopathy (VER) disease has been confirmed to be caused by RGNNV/SJNNV reassortants. Because of this, seabream larvae at 37 and 86 days post-hatching (dph) were infected by immersion with RGNNV/SJNNV and SJNNV/RGNNV reassortants under laboratory conditions, and mortality, viral replication and immunity were evaluated. Our results show that gilthead seabream larvae, mainly those at 37 dph, are susceptible to infection with both NNV reassortant genotypes, with the highest impact from the RGNNV/SJNNV reassortant. In addition, viral replication occurs at both ages (37 and 86 dph) but the recovery of infective particles was only confirmed in 37 dph larvae,; this value was also highest with the RGNNV/SJNNV reassortant. Larvae immunity, including the expression of antiviral, inflammatory and cell-mediated cytotoxicity genes, was affected by NNV infection. Levels of the natural killer lysin (Nkl) peptide were increased in SJNNV/RGNNV-infected larvae of 37 dph, though hepcidin was not. Our results demonstrate that the seabream larvae are susceptible to both NNV reassortants, though mainly to RGNNV/SJNNV, in an age-dependent manner.  相似文献   

17.
Caper (Capparis spinosa) seed oil growing wild in Iran was extracted using supercritical CO2 and ultrasound-assisted extraction methods. The experimental parameters of SFE and UAE were optimized using a rotatable central composite design. The highest yield for SFE was obtained at a pressure of 355 bar, temperature of 65 °C, modifier volume of 140 μL, static and dynamic extraction time of 10 and 35 min, respectively, and for UAE was gained at solvent volume of 23 mL, sonication time of 45 min and temperature of 40 °C. This resulted in a maximum oil recovery of 25.1% and 27.9% for SFE and UAE, respectively. The extracts with higher yield from both methods were subjected to transesterification and GC–MS analysis. SFE and UAE processes selectively extracted the fatty oils with high percentage of omega-6 and omega-9-fatty acids. The major components of the extracted oils from both methods were linoleic, oleic, its positional isomer cis-vaccenic and Palmitic acid.  相似文献   

18.
This study reports the benefits of auxiliary degumming (Aux.D) and pressurized high temperature (165 °C) water washing (PHTW) to mitigate the formation of monochloropropanediols (MCPD) during labscale physical refining of palm oil. Water-based degumming in combination with bleaching and deodorization are performed as the selected physical refining process. The mitigation concepts Aux.D and PHTW are integrated into the refining protocol and the ultimately observed MCPD levels in the fully refined oils are determined. Aux.D is performed by extracting the hydratable gum from pressed sunflower oil and using it as a degumming agent to further purify palm oil that has been previously subjected to centrifugation and water degumming. This approach enables the mitigation of 3-MCPD from the water washed reference 2.4–0.9 mg kg−1 in ampoules. Even stronger mitigation is obtained when Aux.D is combined with bleaching and executed twice allowing a mitigation from the reference 1.9–0.6 mg kg−1, in ampoules. PHTW is shown to decrease the 3-MCPD content of the refined oil from the reference 2.4–1 mg kg−1, in ampoules and when combined with bleaching and executed twice showing a decrease from the reference 1.9–0.9 mg kg−1. Practical applications: The benefits of these mitigation concepts are confirmed both in sealed ampoule tests and in deodorizer experiments at the lab scale. A combined application of Aux.D or PHTW with physical refining may represent new insights that can help to potentially further mitigate the formation of MCPD in physically refined palm oil beyond the limits achievable with current refining practices.  相似文献   

19.
Annona squamosa and Catunaregam nilotica seeds and oils were characterized for their approximate analysis and physico-chemical properties. The oil and protein contents were 26.8, 17.5 and 40.0, 22.2%, in A. squamosa and C. nilotica seeds, respectively. The oils were extracted using cold extraction (CE) and Soxhlet extraction (SE) methods. Fatty acids and tocopherols were determined by GC–MS and HPLC, respectively. Generally the physico-chemical properties and fatty acids were not significantly (P ≤ 0.05) affected by the extraction methods. The major fatty acids of A. squamosa oil extracted by CE and SE were oleic 49.2 and 50.5%, linoleic 22.3 and 22.7%, palmitic 15.6 and 15.2%, and stearic 10.6 and 9.3%, respectively. While the major fatty acids in C. nilotica oil extracted by CE and SE were oleic 10.5, and 10.4%, linoleic 63.1 and 63.4%, palmitic 9.7 and 9.8% and stearic 5.1 and 5.4%, respectively. The tocopherol content of CE and SE extracted oils from A. squamosa amounted to 16.6 and 15.5 and from C. nilotica amounted to 110.5 and 107.7 mg/100 g oil, respectively, with delta-tocopherol as the predominant tocopherol in A. squamosa oil, and beta-tocopherol in C. nilotica oil. The total amount of amino acids was found to be 7.266 and 14.202 g/100 g protein, in seeds of A. squamosa and C. nilotica, respectively.  相似文献   

20.
Supercritical fluid extraction (SFE) of sorghum bug oil (SBO) with carbon dioxide was performed and compared with Soxhlet extraction using hexane. Response surface methodology (RSM) was used to determine the effects of pressure (200–400 bar) and temperature (50–70 °C) on the sorghum bug oil yield in SC-CO2. The high extraction yield (more than 45.0%) was obtained at 300 bar and 60 °C followed by 400 bar and 70 °C, while the lower yield was obtained at 159 bar and 60 °C. At low pressure levels (159 and 200 bar), the oil yield decreased due to the reduced density of CO2 at higher temperatures. Gas chromatography was used to characterize the fatty acids of the oils obtained while α-tocopherol was quantified by HPLC. No differences were found in the fatty acid compositions of the various extracts, while the α-tocopherol extracted from sorghum bug oil by the conventional solvent method was less than that extracted by the SFE process using CO2. It can be observed that the conventional solvent extraction method exhibited notable DPPH radical-scavenging activity, with an efficacy slightly lower (IC50 7.45 ± 0.3) than that of the SFE extracts.  相似文献   

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