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1.
This study investigated the phytochemical content of alcoholic extracts and essential oil of a new variety of medicinal plants, Agastache foeniculum (Pursh), which Kuntze adapted for cultivation in Romania, namely “Aromat de Buzău”. The essential oil was investigated by GC-MS, while the identification and quantification of various compounds from alcoholic extracts were performed by HPLC-DAD. The total phenol and flavonoid contents of the extracts were evaluated by using standard phytochemical methods. The antioxidant activities of ethanol, methanol extracts, and essential oil of the plant were also assessed against 2,2′-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), and by ferric reducing power (FRAP) using spectroscopic methods. Cyclic voltammetry was used to evaluate the antioxidant capacity of the essential oil. The concentrations of phenolic compounds were higher in methanolic extract compared to ethanolic extract. A significant correlation was found between total phenol and total flavonoid contents (r = 0.9087). Significant high correlations were also found between the total phenolic compounds and the antioxidant activities of the extracts (r ≥ 0.8600, p < 0.05). In addition, the extracts and essential oil showed good antioxidant and xanthine oxidase inhibitory activities. Estragole was detected as the major constituent of the essential oil (94.89%). The cytotoxic activity of the essential oil was evaluated by the MTT assay. At lower concentrations (1 µg/mL) high cytotoxicity against MCF-7 breast cancer cells was observed but not on the non-tumoral dermal fibroblasts (HDF) which indicated selectivity for cancer cells and suggests the presence of biologically active components that contribute to the observed high cytotoxic effect. Findings from the present study offer new perspectives on the use of A. foeniculum as a potential source of bioactive compounds and a good candidate for pharmaceutical plant-based products.  相似文献   

2.
The effects of two commercial endoproteases (Protex 6L and Protex 7L, Genencor Division of Danisco, Rochester, NY, USA) on the oil and protein extraction yields from extruded soybean flakes during enzyme-assisted aqueous extraction processing (EAEP) were evaluated. Oil and protein were distributed in three fractions generated by the EAEP: cream + free oil, skim and insolubles. Protex 6L was more effective for extracting free oil, protein and total solids than Protex 7L. Oil and protein extraction yields of 96 and 85%, respectively, were obtained using 0.5% Protex 6L. Enzymatic and pH treatments were evaluated to de-emulsify the oil-rich cream. Cream de-emulsification generated three fractions: free oil, an intermediate residual cream layer and an oil-lean second skim. Total cream de-emulsification was obtained when using 2.5% Protex 6L and pH 4.5. The extrusion treatment was particularly important for reducing trypsin inhibitor activity (TIA) in the protein-rich skim fraction. TIA reductions of 69 and 45% were obtained for EAEP skim (the predominant protein fraction) from extruded flakes and ground flakes, respectively. Protex 6L gave higher degrees of protein hydrolysis (most of the polypeptides being between 1,000 and 10,000 Da) than Protex 7L. Raffinose was not detected in the skim, while stachyose was eliminated by α-galactosidase treatment.  相似文献   

3.
通过正交试验探讨了巨尾桉叶中原花色素的3种提取方法的最佳提取工艺条件,并进行了对比。结果显示,传统溶剂提取法的最优工艺为:60%乙醇、80 ℃、100 min、料液比1:14(g:mL,下同),原花色素得率5.95%;微波辅助提取法的最优工艺为:50%乙醇、微波功率200 W、微波时间4 min、料液比为1:20,得率5.48%;超声波辅助提取法的最优工艺为:60%乙醇、60 ℃、超声波时间25 min、料液比为1:14,得率为6.07%。超声波辅助提取法效果最好,时间短,得率高。实验对超声波提取物的不同溶剂萃取物体外抗氧化性和抗肿瘤活性进行了研究,结果表明,乙酸乙酯萃取物抗氧化作用较强,当质量浓度为1.2 g/L时,对DPPH自由基清除率达到96.33%;乙酸乙酯萃取物质量浓度为2 g/L时,对于人肝癌细胞Bel-7404具有很强的抗肿瘤活性,抑制率为56.37%。  相似文献   

4.
Enzyme-assisted aqueous extraction processing (EAEP) is an increasingly viable alternative to hexane extraction of soybean oil. Although considered an environmentally friendly technology where edible oil and protein can be simultaneously recovered, this process employs much water and produces a significant amount of protein-rich aqueous effluent (skim). In standard EAEP, highest oil, protein and solids yields are achieved with a single extraction stage using 1:10 solids-to-liquid ratio (extruded flakes/water), 0.5% protease (wt/g extruded flakes), pH 9.0, and 50 °C for 1 h. To reduce the amount of water used, two-stage countercurrent EAEP was evaluated for extracting oil, protein and solids from soybeans using a solids-to-liquid ratio of 1:5–1:6 (extruded flakes/water). Two-stage countercurrent EAEP achieved higher oil, protein and solids extraction yields than using standard EAEP with only one-half the usual amount of water. Oil, protein and solids yields up to 98 and 96%, 92 and 87%, and 80 and 77% were obtained when using two-stage countercurrent EAEP (1:5–1:6) and standard single-stage EAEP (1:10), respectively. Recycling the second skim obtained in two-stage countercurrent EAEP enabled reuse of the enzyme, with or without inactivation, in the first extraction stage producing protein with different degrees of hydrolysis and the same extraction efficiency. Slightly higher oil, protein and solids extraction yields were obtained using unheated skim compared to heated skim. These advances make the two-stage countercurrent EAEP attractive as the front-end of a soybean biorefinery.  相似文献   

5.
An aqueous enzymatic extraction method was developed to obtain free oil and protein hydrolysates from dehulled rapeseeds. The rapeseed slurry was treated by the chosen combination of pectinase, cellulase, and β-glucanase (4:1:1, v/v/v) at concentration of 2.5% (v/w) for 4 h. This was followed by sequential treatments consisting of alkaline extraction and an alkaline protease (Alcalase 2.4L) hydrolysis to both produce a protein hydrolysate product and demulsify the oil. Response surface methodology (RSM) was used to study and optimize the effects of the pH of the alkaline extraction (9.0, 10.0 and 11.0), the concentration of the Alcalase 2.4L (0.5, 1.0 and 1.5%, v/w), and the duration of the hydrolysis (60, 120, and 180 min). Increasing the concentration of Alcalase 2.4L and the duration of the hydrolysis time significantly increased the yields of free oil and protein hydrolysates and the degree of protein hydrolysis (DH), while the alkaline extraction pH had a significant effect only on the yield of the protein hydrolysates. Following an alkaline extraction at pH 10 for 30 min, we defined a practical optimum protocol consisting of a concentration of 1.25–1.5% Alcalase 2.4L and a hydrolysis time between 150 and 180 min. Under these conditions, the yields of free oil and protein hydrolysates were 73–76% and 80–83%, respectively. The hydrolysates consisted of approximately 96% of peptides with a MW less than 1500, of which about 81% had a MW less than 600 Da.  相似文献   

6.
Downstream processes following aqueous enzymatic extraction (AEE) of rapeseed oil and protein hydrolysates were developed to enhance the oil and protein yields as well as to purify the protein hydrolysates. The wet precipitate (meal residue) from the AEE was washed with twofold water at 60 °C, pH 11 for 1 h. Emulsions from the AEE and the washing step were pooled and submitted to a stepwise demulsification procedure consisting of storage-centrifugation and freezing–thawing followed by centrifugation. Aqueous phases were pooled and adsorbed onto macroporous adsorption resins (MAR) to remove salts and sugars. Following extensive rinsing with deionized water (pH 4), desorption was achieved by washing with 85% ethanol (v/v) to obtain crude rapeseed peptides (CRPs). In a separate experiment, stepwise desorption was carried out with 25, 55, and 85% ethanol to separate the bitter peptides from the other peptides. Using a combination of the AEE process, washing and demulsification steps, the yields of the total free oil and protein hydrolysates were 88–90% and 94–97%, respectively. The protein recovery was 66.7% and the protein content was enriched from 47.04 to 73.51% in the CRPs. No glucosinolates and phytic acid were detected in the CRPs. From the stepwise desorption, a non-bitter fraction RP25 (containing 64–66% of total desorbed protein) had a bland color and significantly higher protein content (81.04%) and hence was the more desirable product.  相似文献   

7.
The antioxidant activities of the raisin extract (RE) in stripped corn oil, stripped corn oil emulsions, and sunflower butter stored at 60 °C for up to 15 days was evaluated. Peroxide values and hexanal content were measured on a half day, 2 or 3 day basis for the emulsion, sunflower butter, and bulk oil, respectively. The RE had the best antioxidant activity in the bulk oil system. Statistical contrasts indicated the oxidation of bulk corn oil treated with RE was significantly (p < 0.001 and p = 0.044) lower than bulk oil and bulk oil treated with tertiary-butylhydroquinone (TBHQ), respectively. No differences (p = 0.15) in hexanal concentrations were observed in stored bulk oils treated with RE and TBHQ. However, both these materials inhibited hexanal formation better (p < 0.001) when compared to the control corn oil. In contrast, 200 μg/g TBHQ had better (p = 0.0004) antioxidant activity than 3,000 μg/g RE in the oil in water(o/w) emulsion. No significant differences (p = 0.1637) in hexanal formation were observed in the emulsions treated with RE and TBHQ. However, the data indicated that the RE treated emulsion did undergo more secondary oxidation than the emulsion treated with TBHQ beyond 110 h. The 3,000 μg/g RE had antioxidant activity in sunflower butter, but was less effective than the 200 μg/g TBHQ and a lower RE concentration (200 μg/g). The observations supported the hypothesis that RE has antioxidant activity in the multiple model systems.  相似文献   

8.
We assessed the anti-Listerial activities of crude n-hexane and aqueous extracts of Garcinia kola seeds against a panel of 42 Listeria isolates previously isolated from wastewater effluents in the Eastern Cape Province of South Africa and belonging to Listeria monocytogenes, Listeria grayi and Listeria ivanovii species. The n-hexane fraction was active against 45% of the test bacteria with zones of inhibition ranging between 8-17 mm, while the aqueous fraction was active against 29% with zones of inhibition ranging between 8-11 mm. The minimum inhibitory concentrations (MIC) were within the ranges of 0.079-0.625 mg/mL for the n-hexane extract and 10 to >10 mg/mL for the aqueous extract. The rate of kill experiment carried out for the n-hexane extract only, revealed complete elimination of the initial bacterial population for L. grayi (LAL 15) at 3× and 4× MIC after 90 and 60 min; L. monocytogenes (LAL 8) at 3× and 4× MIC after 60 and 15 min; L. ivanovii (LEL 18) at 3× and 4× MIC after 120 and 15 min; L. ivanovii (LEL 30) at 2, 3 and 4× MIC values after 105, 90 and 15 min exposure time respectively. The rate of kill activities were time- and concentration-dependant and the extract proved to be bactericidal as it achieved a more than 3log(10) decrease in viable cell counts after 2 h exposure time for all of the four test organisms at 3× and 4× MIC values. The results therefore show the potential presence of anti-Listerial compounds in Garcinia kola seeds that can be exploited in effective anti-Listerial chemotherapy.  相似文献   

9.
《分离科学与技术》2012,47(1):243-262
Abstract

Microwave-assisted extraction (MAE) was applied for the extraction of astaxanthin from Haematococcus pluvialis and response surface methodology (RSM) was used to optimize extraction parameters to the content of astaxanthin. Four independent variables such as microwave power (W), extraction time (sec), solvent volume (mL), and the number of extraction were optimized in this paper. The optimal conditions were determined and tri-dimensional response surfaces were plotted from the mathematical models. The F-test and p-value indicated that microwave power, extraction time, the number of extraction, and their quadratic had a highly significant effect on the response value (p <0.01), then the solvent volume and the interaction effects of microwave power and the number of extraction also displayed significant effect (p <0.05). Considering the extraction efficiency, the optimized conditions of MAE were as follows: microwave power was 141 W, extraction time 83 sec, solvent volume 9.8 mL, the number of extraction four times. About 594 ± 3.02 µg astaxanthin was extracted from Haematococcus pluvialis the dried powders (100 mg) under the optimal conditions, and it close to the predicted contents (592 µg). The antioxidant activities of the extracts obtained under optimal conditions were analyzed, and the results showed that the extracts presented strong ability of inhibiting the peroxidantion of linoleic acid, exhibited strong radical-scavenging properties against the DPPH, as well as strong reducing power.  相似文献   

10.
The influence of the conditions for isolation of soy protein on the content of genistein and its conjugated forms was studied. The major components of the genistein series isolated from soybean flour were malonyl genistin (54.3%), genistin (36.9%), and equal amounts (4.4%) of genistein and acetyl genistin. A modification in the conjugation profile of genistein between pH 4.5 and 8.0 and above pH 10 was attributed to the action of β-glucosidase and the saponification reaction, respectively. A decrease in the content of total genistein in the insoluble flour residue and in the soy protein isolate (SPI) with increasing extraction pH was detected, while in the whey, the total genistein content was not affected by pH. The effect of pH variation during acid precipitation on the content of genistein and its conjugated forms, at a constant extraction pH (8.0), was also studied. Under these conditions, the highest absolute content of total genistein in the SPI was obtained at pH 3.5 and the lowest was obtained at pH 5.6. The total genistein content in the whey followed an inverse trend compared with that of the protein yield. A temperature increase did not substantially affect the distribution of the different genistein forms or their total contents. The content of total genistein was higher in the glycinin than in the β-conglycinin protein fraction. The effect of the pH during the alcohol/water extraction of the isoflavones was also analyzed. The efficiency of the extraction was lower at pH values between 3.25 and 3.5 than at other pH values.  相似文献   

11.
12.
Camellia tenuifloria is an indigenous Camellia species used for the production of camellia oil in Taiwan. This study investigated for the first time the potential antioxidant, anti-tyrosinase and anti-inflammatory activities of oil production byproducts, specifically those of the fruit shell, seed shell, and seed pomace from C. tenuifloria. It was found that the crude ethanol extract of the seed shell had the strongest DPPH scavenging and mushroom tyrosinase inhibitory activities, followed by the fruit shell, while seed pomace was the weakest. The IC50 values of crude extracts and fractions on monophenolase were smaller than diphenolase. The phenolic-rich methanol fraction of seed shell (SM) reduced nitric oxide (NO) production, and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. It also repressed the expression of IL-1β, and secretion of prostaglandin E2 (PGE2) and IL-6 in response to LPS. SM strongly stimulated heme oxygenase 1 (HO-1) expression and addition of zinc protoporphyrin (ZnPP), a HO-1 competitive inhibitor, reversed the inhibition of NO production, indicating the involvement of HO-1 in its anti-inflammatory activity. The effects observed in this study provide evidence for the reuse of residues from C. tenuifloria in the food additive, medicine and cosmetic industries.  相似文献   

13.
Natural antioxidants to inhibit oxidation in edible oils are in high demand. Grape pomace is an abundant, inexpensive source of polyphenolic antioxidants, which are responsible for numerous health benefits. We examined pomace from eight varieties of Midwestern hybrid grapes for phenolic content and antioxidant activity. Ethanolic extracts produced from the pomace of each grape variety were added to two model systems, bulk soybean oil and oil‐in‐water emulsions, to determine antioxidant activity. Oxidation was monitored in each model system at a temperature appropriate to that particular system. While the extracts had relatively little effect in bulk oil, we observed dose‐dependent antioxidant effects of some extracts in oil‐in‐water emulsions. Oxidation in bulk oils was assessed via total polar compounds and polymerized triacylglycerols. Oxidation in emulsions was assessed by peroxide value, headspace oxygen measurements, gas chromatography of headspace volatiles, and fatty acid analysis. Pomace extracts derived from red grapes generally outperformed those from white grapes, with the Marechal Foch variety showing high antioxidant activity at intermediate concentrations. At higher concentrations, Marechal Foch, Corot Noir, Frontenac, and Norton extracts showed promising antioxidant activity. This is the first report on antioxidant activity in an oil and emulsion setting for many of these grape varieties.  相似文献   

14.
Oxidative stability of lipids is one of the most important parameters affecting their quality. Lipase‐catalyzed lipophilic tyrosyl esters with an equivalent carbon alkyl chain but different degrees of unsaturation (C18:0 to C18:4n3) were prepared, characterized, and used as antioxidants. Free fatty acids and fatty acid ethyl esters (substrate molar ratio tyrosol: acyl donor, 1:10) were used as acyl donors and immobilized lipase from Candida antarctica was the biocatalyst (10 %). The phenolipids were isolated and characterized using ESI–MS, 1H‐NMR, and 13C‐NMR. Peroxide value (PV) and para‐anisidine value (p‐AV) were measured to evaluate their antioxidant activities in bulk oil structured lipid (SL) and in an oil‐in‐water emulsion (SL‐based infant formula). No significant difference was found in yield and reaction time between the two types of acyl donors. However, as the unsaturation of the fatty acids increased the reaction time also increased. In SL, tyrosyl esters exhibited lower antioxidant activity than tyrosol whereas the addition of an alkyl chain enhanced the antioxidant efficiency of tyrosol in infant formula. Tyrosyl oleate was the most efficient antioxidant in the emulsion system followed by tyrosyl stearate and tyrosyl linoleate. These results suggest that the synthesized phenolipids may be used as potential antioxidants in lipid‐based products.  相似文献   

15.
Endopleura uchi is a typical Amazonian tree and its bark is popularly employed in the preparation of teas against myomas, arthritis, influenza, diarrhea and cancer. In this study, the antioxidant activity, cytotoxicity and antimicrobial activity of five different extracts of the bark, selected by their total tannin content, were assessed. The potential antioxidant activity of the extracts was determined by 2.2-diphenyl-1-picrylhydrazyl radical scavenging assay and the values found were very similar among the extracts and to the standards antioxidants used in the tests. Cytotoxicity analysis in mammalian cells indicated that all the tested extracts exhibited IC(50) values higher than the highest concentration used, showing that they do not present a risk when consumed under these conditions. Extract tested against five bacterial strains and one yeast strain did not show satisfactory growth inhibitory activity, and even the extracts that showed some antimicrobial activity were not effective at any dilution to determine the minimum inhibitory concentration. The results may serve as a reference for subsequent works, since such reference values described in the literature for the bark of E. uchi.  相似文献   

16.
This study was designed to examine physicochemical composition, antioxidant activities and heat stability of corn oil enriched with bitter orange peel. Volatile compounds composition of corn oil flavored with Citrus aurantium peel was investigated. Flavored oil total aroma content (2.6 mg/mg oil) was mainly represented by monoterpene hydrocarbons and limonene was the major one (2.49 mg/mg oil). Flavored oil methanolic extract was characterized by total phenol content of 1.22 mg GAE/kg. Chlorogenic, ferulic and p-coumaric acids were the major phenolic components of the flavored oil extract (34.33, 30.24 and 19.39 %, respectively). It was also characterized by a higher chlorophylls and carotenoids contents than the refined one. Antioxidant activities of methanolic extracts of both samples were determined using four assays: DPPH, reducing power, β-carotene bleaching and metal chelating tests. In β-carotene bleaching and DPPH radical scavenging assays, flavored oil methanolic extract showed higher activities than the control. It was characterized by a total antioxidant activity of 4.08 mg GAE/kg and an EC50 value of 3.14 mg/mg oil. Its concentration providing 50 % inhibition (IC50) was 0.53 mg/mg oil in the DPPH test and 4.08 mg/mg oil in the β-carotene bleaching test. However, refined corn extract showed significantly lower antioxidant activities (p < 0.05). Results of the oxidative stability index showed bitter orange peel effectiveness against thermal oxidation based on the increased induction time observed in flavored oil (5.95).  相似文献   

17.
Cancer-associated fibroblasts (CAFs) are an essential component of the tumour microenvironment. They represent a heterogeneous group of cells that are under the control of cancer cells and can reversely influence the cancer cell population. They affect the cancer cell differentiation status, and the migration and formation of metastases. This is achieved through the production of the extracellular matrix and numerous bioactive factors. IL-6 seems to play the central role in the communication of noncancerous and cancer cells in the tumour. This review outlines the role of exosomes in cancer cells and cancer-associated fibroblasts. Available data on the exosomal cargo, which can significantly intensify interactions in the tumour, are summarised. The role of exosomes as mediators of the dialogue between cancer cells and cancer-associated fibroblasts is discussed together with their therapeutic relevance. The functional unity of the paracrine- and exosome-mediated communication of cancer cells with the tumour microenvironment represented by CAFs is worthy of attention.  相似文献   

18.
19.
Interest in plant compounds has increased, given recent evidence regarding their role in human health due to their pleiotropic effects. For example, plant bioactive compounds present in food products, including polyphenols, are associated with preventive effects in various diseases, such as cancer or inflammation. Breast and colorectal cancers are among the most commonly diagnosed cancers globally. Although appreciable advances have been made in treatments, new therapeutic approaches are still needed. Thus, in this study, up to 28 olive leaf extracts were obtained during different seasons and using different drying temperatures. The influence of these conditions on total polyphenolic content (measured using Folin–Ciocalteu assays), antioxidant activity (using Trolox Equivalent Antioxidant Capacity and Ferric Reducing Ability of Plasma assays) and antiproliferative capacity (using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, MTT assays) was tested in breast and colorectal cancer cells. Increased phenolic composition and antioxidant and antiproliferative capacity are noted in the extracts obtained from leaves harvested in autumn, followed by summer, spring and winter. Regarding drying conditions, although there is not a general trend, conditions using the highest temperatures lead to the optimal phenolic content and antioxidant and antiproliferative activities in most cases. These results confirm previously published studies and provide evidence in support of the influence of both harvesting and drying conditions on the biological activity of olive leaf extracts.  相似文献   

20.
In this study, the essential oil (EO) constituents from the aerial parts of Satureja intermedia C.A.Mey were detected by GC and GC/MS. The antimicrobial activity of EO on oral pathogens and its cytotoxicity to human cancer cells were determined by the microbroth dilution method and the crystal violet staining method, respectively. Thirty-nine compounds were identified and the main EO constituents were γ-terpinene (37.1%), thymol (30.2%), p-cymene (16.2%), limonene (3.9%), α-terpinene (3.3%), myrcene (2.5%), germacrene B (1.4%), elemicine (1.1%) and carvacrol (0.5%). The S. intermedia EO showed a concentration-dependent decrease in viability of Hep-G2 (hepatocellular carcinoma) and MCF-7 (breast adenocarcinoma) human cancer cell lines (p < 0.05). Antimicrobial screening of S. intermedia EO demonstrated slight antibacterial and antifungal activities against Streptococcus mutants, S. salivarius, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. glabrata. Further preclinical studies are needed to assess the efficacy and safety of S. intermedia EO as a new promising anticancer agent.  相似文献   

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