三种植物精油的成分分析及其抑菌活性比较

为比较柠檬草、茉莉花、姜黄三种植物精油的组成成分及其抑菌活性,本试验采用气相色谱-质谱联用仪（GC-MS）分析样品成分,进而通过滤纸片法和梯度稀释法分析样品的抑菌能力。试验结果表明：姜黄精油主要特征成分为姜黄酮（12.87%）、芳姜黄酮（38.53%）和姜酮（20.36%）,具有抑菌活性的成分包括莰烯（2.38%）等;柠檬草精油的主要成分为柠蒙烯（12.72%）、柠檬醛（8.52%）和异松油烯（17.53%）,具有抑菌活性的成分包括柠檬醛（8.52%）等;茉莉精油的主要特征成分为芳樟醇（11.88%）、乙酸苄酯（9.31%）和肉桂醛（31.87%）,具有抑菌活性的成分包括肉桂醛（31.87%）等。柠檬草精油、茉莉精油、姜黄精油对金黄色葡萄球菌的抑菌圈直径分别为20.10 mm、10.22 mm、7.84 mm,阳性对照的乳酸链球菌素抑菌圈直径则为13.40 mm。上述三种植物精油均包含具有一定抑菌活性的物质,且在抑菌圈试验中表现出抑菌性,与乳酸链球菌素相比,抑菌效果从强到弱依次为柠檬草精油>茉莉精油>姜黄精油。     

Inhibition of lipid oxidation in anchovy oil (Engraulis encrasicholus) enriched emulsions during refrigerated storage

The aim of this study was to produce a functional emulsion product enriched with anchovy (Engraulis encrasicholus) oil. Tomato and garlic extracts were added to perform oxidative stability. Tomato and garlic extracts were added to avoid oxidative degradation in such a product. The plant extracts delayed the formation of primary and secondary oxidation products. The value of conjugated diens (3.07 ± 0.15) was markedly low in the emulsions containing garlic extract at the end of the storage period. The p–Av values of the emulsions treated with the extracts were significantly (P < 0.01) lower than untreated samples. TBARS formation increased slightly, therewithal statistical difference was not observed in the samples treated with garlic extract during the storage. Strong odour and flavour of the garlic suppressed the odour of fish oil. The panellists preferred the flavour, odour and aroma characteristics of the samples treated with the extracts.     

In vitro and in vivo assessment of the effect of Laurus novocanariensis oil and essential oil in human skin

Laurus novocanariensis is an endemic plant from the Madeira Island forest that derives a fatty oil, with a strong spicy odour, from its berries that has been used for centuries in traditional medicine to treat skin ailments. This work aimed to investigate the effect of the application of both the oil and its essential oil on normal skin, to assess their safety and potential benefits. Diffusion studies with Franz cells using human epidermal membranes were conducted. The steady‐state fluxes of two model molecules through untreated skin were compared with those obtained after a 2‐h pre‐treatment with either the oil or the essential oil. Additionally, eleven volunteers participated in the in vivo study that was conducted on the forearm and involved daily application of the oil for 5 days. Measurements were performed every day in the treated site with bioengineering methods that measure erythema, irritation and loss of barrier function. Slightly higher steady‐state fluxes were observed for both the lipophilic and the hydrophilic molecule when the epidermal membranes were pre‐treated. Nevertheless, such differences had no statistical significance, which seems to confirm that neither the oil nor the essential oil impaired the epidermal barrier. Results collected with the Chromameter, the Laser Doppler Flowmeter and the visual scoring are in agreement with those established in the in vitro study. They indicate that the repeated application of the oil did not cause erythema, because the results observed in the first day of the study were maintained throughout the week. Application of the oil did not affect the skin barrier function, because the transepidermal water loss remained constant throughout the study. The stratum corneum hydration was slightly reduced on days 4 and 5. This work shows that both the oil and the essential oil were well tolerated by the skin and did not cause significant barrier impairment or irritation.     

The relationship between odour intensity and antibacterial durability of encapsulated thyme essential oil by PPI dendrimer on cotton fabrics

The relationship between odour intensity and antibacterial properties of thyme essential oil (EO) in the presence of second generation of polypropylene Imine (PPI-G2) dendrimer as a control release agent was investigated. Odour release of thyme EO from treated fabric was measured via an electronic nose (e-nose). Staphylococcus Aureus and Escherichia Coli were considered as target bacteria to evaluate the antibacterial activity of treated fabrics. Results reveal that PPI-G2 dendrimer has strong effect on antibacterial retention under washing process and exposing to the free air. Furthermore, FTIR results show the reaction between PP-G2 and thyme EO on cotton fabrics. E-nose data also indicated that PPI-G2 provided controlled release of odour from treated fabric since the rate of odour release of samples with the dendrimer was much slower than samples without the dendrimer. It was found that e-nose results correlated with antibacterial activity with correlation coefficient of r = 0.988 for samples without PPI-G2.     

Antimicrobial Activity of a Pullulan–Caraway Essential Oil Coating on Reduction of Food Microorganisms and Quality in Fresh Baby Carrot

This research evaluated the antimicrobial efficacy of pullulan films containing caraway essential oil (CEO). The films were prepared from a 10% of pullulan, containing from 0.12% to 10.0% of CEO. The composition of the CEO was analyzed with the use of gas chromatography. The antimicrobial activity of the CEO was evaluated with the method of serial microdilutions, and the films containing CEO—with the agar diffusion method against selected Gram‐negative, Gram‐positive bacteria, and fungi. The structure of the film surface and its cross‐section were analyzed using a scanning electron microscope (SEM). Analyses were also carried out to determine the efficacy of a pullulan coating with 10% CEO on baby carrots experimentally inoculated with Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae, or Aspergillus niger and stored at a room temperature for 7 d. At a concentration of 0.12%, CEO inhibited the growth of all the tested microorganisms. Pullulan films containing 8% to 10% of CEO were active against all tested microorganisms. Populations of S. aureus on carrot samples were reduced by approximately 3 log CFU/g, while those of A. niger and S. cerevisiae by, respectively, 5 and 4 log CFU/g, after 7 d of storage. S. enteritidis was the most resistant among the tested species, since it was not significantly reduced after 7 d of storage. At the end of storage, samples treated with pullulan–caraway oil coating maintained better visual acceptability than control samples. Results of this study suggest the feasibility of applying a pullulan film with incorporated CEO to extend the microbiological stability of minimally processed foods.     

Effect of distillation waste water and plant hormones on spearmint growth and composition

BACKGROUND: Distillation waste water (DWW) is a by‐product from steam distillation of essential‐oil crops; and currently, it is discharged into streams and rivers. The effects of DWW from 13 essential‐oil crops, extracts from two alkaloid‐containing species, and three plant hormones (methyl jasmonate, MJ; gibberellic acid, GA3; and salicylic acid, SA) were evaluated on productivity, essential‐oil content and composition of spearmint (Mentha spicata L.) cv. ‘Native’. RESULTS: Spearmint plant height was increased by the application of GA3 and Melissa officinalis DWW but suppressed by the application of Rosmarinus officinalis and Tagetes lucida DWW. Generally, MJ, GA3 and M. officinalis and Mentha arvensis DWW increased dry yields. The concentration of L ‐carvone in the oil ranged from 550 g kg^?1 (with Monarda citriodora DWW) to 670 g kg^?1 (with T. lucida DWW). M. citriodora DWW reduced the concentration of L ‐carvone in the oil by 23% relative to the control. CONCLUSION: Results suggest that DWW from essential‐oil crops may affect monoterpene synthesis in M. spicata and, hence, may have a direct effect on the essential oil composition. DWW from essential‐oil crops may be used as a growth promoter and modifier of the essential oil composition of spearmint. Copyright © 2011 Society of Chemical Industry     

茉莉精油微胶囊香气成分的释放研究

研究了茉莉精油的挥发性、茉莉精油微胶囊的总精油含量及表面含油量,分析了茉莉精油微胶囊总精油及表面含油量在贮存过程中的变化。研究结果表明:微胶囊在贮存过程中,茉莉精油的损失主要是微胶囊表面油的损失,并得出微胶囊对茉莉精油香气成分的保存是十分有效的结论。对各释放结果逐一进行了数学方程拟合,取得了较高的置信度。     

Preparation and application of a flaxseed meal protein film containing lemongrass (Cymbopogon citratus) oil

Flaxseed meal protein (FMP) films were prepared, and their mechanical properties (tensile strength (TS) and elongation at break (E) values), water vapour permeability, optical properties and thermogravimetric analysis were evaluated. Briefly, 5 g FMP, 2 g fructose and 0.03 g ferulic acid were required for the optimal preparation of an FMP film. The TS and E values of the FMP film were 13.12 MPa and 61.90%, respectively. Furthermore, different amounts of lemongrass oil (LE) were incorporated into the FMP film to prepare an antimicrobial film. Wrapping pen shell adductor muscle with the FMP film containing 1.0% LE reduced the counts of inoculated Listeria monocytogenes and Escherichia coli O157:H7 compared with those in the control, after storage at 4 °C for 12 day. Consequently, packaging with FMP film containing 1.0% LE can be useful in improving the quality of pen shell adductor muscle during storage.     

Microencapsulation of shiitake (Lentinula edodes) essential oil by complex coacervation: formation,rheological property,oxidative stability and odour attenuation effect

Complex coacervation of gelatin (GE) with carboxymethylcellulose (CMC) and the microencapsulation of shiitake essential oil (SEO) using the GE‐CMC coacervate were investigated. The ζ‐potential and coacervate yield data showed that the optimal complexation pH and CMC/GE ratio were 4.0 and 0.15 g g^?1, respectively. At this condition, the coacervate yield was 85.35 ± 4.89% and ζ‐potential was almost zero. The SEO contained microcapsules fabricated by the GE‐CMC coacervate were also electrostatic inducted formation, and the highest encapsulation efficiency was shown to be 85.75 ± 2.89%. The rheological measurement indicated that the GE‐CMC coacervated microcapsules had a viscoelastic solid behaviour (G’ > G”) which was resulted mainly from the interactions between GE molecules and CMC chains. The improved oxidative stability and odour attenuation effect of the GE‐CMC coacervated microcapsules were believed to be attributed to the increased protection against oxidation and flavour release by providing a physical barrier after complex coacervation.     

Nutritional and sensory aspects of light lamb meat enriched in n−3 fatty acids during refrigerated storage

Fatty acid content and sensory characteristics of meat from light lambs fed three diets supplemented with different sources of n−3 fatty acids (fish oil, extruded linseed and extruded linseed plus microalgae) and a control diet during refrigerated storage have been studied. The meat from lambs fed linseed diets had the highest levels of C18:3 n−3, while animals fed fish oil had the highest long-chain n−3 polyunsaturated fatty acids (PUFA). Thus, 100 g of meat from lamb fed the fish oil diet provided 183 mg of long-chain n−3 PUFA, representing 40% of the daily recommended intake. The levels of n−3, n−6 and long-chain n−3 PUFA decreased during a 7-day storage period. The meat from lambs fed the fish oil diet had high scores of fish odour and flavour and rancid odour and flavour and the lowest overall liking. Rancid odour and flavour increased after storage, mainly in supplemented groups.     

Characteristics and antioxidant activity of leaf essential oil–incorporated fish gelatin films as affected by surfactants

Characteristics of film from fish skin gelatin incorporated with four leaf essential oils (lemongrass, basil, citronella and kaffir lime), as influenced by different surfactants (Tween‐20, Tween‐80 and soy lecithin), were investigated. Films incorporated with all essential oils had lower tensile strength with higher elongation at break and thickness, compared with control film (P < 0.05). Films added with Tween‐20 showed higher TS, compared with those containing other surfactants (P < 0.05). Water vapour permeability of films incorporated with all essential oils markedly decreased in comparison with control (P < 0.05). Films generally became darker and more yellowness, when incorporated with essential oils. Film containing basil essential oil had the highest DPPH radical– and ABTS radical–scavenging activities, compared with those added with other essential oils. Higher antioxidative activity was obtained in films containing essential oils when soy lecithin was used as surfactant, probably due to the combined effect of both constituents.     

Damage inhibition during refrigerated storage of mackerel (Scomber scombrus) fillets by a presoaking in quince (Cydonia oblonga) polyphenolic extract

The effect of quince (Cydonia oblonga Miller) polyphenolic extract on preserving mackerel (Scomber scombrus) fillets during refrigerated (4 °C) storage for 11 days was investigated. The quince extract, mainly consisted of procyanidin B dimer (50.8%) and hydroxycinnamic acids (36.62%), was found to quench 2,2‐diphenyl‐1‐picrylhydrazyl radicals by nearly 59.3%. As deduced from the lower peroxide value of the fillet fat fraction and the inhibition of thiobarbituric acid reactive substances formation, the quince extract (8.9 ± 0.4 mg phenolics mL^?1) was found to prevent fish oil from oxidative deterioration compared to control samples. Moreover, the extract was found to be active for in vitro inhibiting the growth of a range of food‐borne bacteria, including Vibrio fluvialis, a halophilic bacterium responsible for a relevant number of sporadic gastroenteritis attributed to contaminated seafood. The minimal inhibition and bactericide concentration (MIC, MBC) values were about 0.37–1.2 mg of polyphenols mL^?1. In a second experiment, following cold smoking of fillets, sensory attributes firmness, astringency, acidity, colour and odour were analysed. The use of multivariate statistical methods (cluster analysis and principal component analysis) revealed no significant differences between samples pre‐treated and non‐pre‐treated (control) with the quince‐phenolic extract.     

Effect of nitrogen application rate on the content and composition of oil,essential oil and minerals in black cumin (Nigella sativa L.) seeds

A field experiment was conducted to study the effect of nitrogen fertility level on the content and composition of oil, essential oil and minerals in black cumin (Nigella sativa L.) seeds. Sixty‐three‐day‐old plants were supplied with varying levels of N, i.e., 0, 30, 60, and 90 kg N ha^?1 soil. The fixed oil content of the seeds ranged from 32.7% to 37.8% and it remained almost unchanged at the two higher external N regimes, i.e., 60 and 90 kg N ha^?1, but at 30 kg N ha^?1 the oil content increased significantly. Of the saturated fatty acids analyzed, palmitic acid increased slightly at all external N levels, but in contrast stearic acid decreased considerably at 60 kg N ha^?1. Of the unsaturated fatty acids of fixed oil, the predominant fatty acid was linoleic acid (18:2) followed by oleic acid (18:1). Linoleic acid and dihomolinoleic acid (20:2) showed no change in their amounts at varying levels of N. In contrast, a marked reduction in α‐linolenic acid (18:3) was found at the two higher N regimes, i.e., 60 and 90 kg N ha^?1. Seed essential oil content did not vary with the change in applied N level. The major component of essential oil of black cumin seed was found to be p‐cymene, which showed an increase at 30 kg N ha^?1, whereas no change in the levels of α‐pinene or β‐pinene was observed at varying levels of N. K, P, Na, Fe, Mn, and Ni were found to be predominant elements in the seeds. Ca, Mg, Cu, and Cr were present in low amounts, but Zn was present in moderate quantity. Increasing N rate did not affect the content of K, P, Ca, Mg, or Cr in the cumin seeds. In contrast, a consistent decrease in seed Mn, Zn, and Ni was observed with increase in external N level. Increasing N level had a marked effect on some of the components of black seed oil. Copyright © 2006 Society of Chemical Industry     

Volatile constituents of roasted tigernut oil (Cyperus esculentus L.)

BACKGROUND: Volatile compounds play a key role in determining the sensory appreciation of vegetable oils. In this study a systematic evaluation of odorants responsible for the characteristic flavour of roasted tigernut oil was carried out. RESULTS: A total of 75 odour‐active volatiles were identified. From these, 13 aroma compounds showing high flavour dilution factors in the range of 16 to 128 were quantified by their odour activity values (OAVs). On the basis of high OAVs in oil, the following aroma compounds [vanillin (chocolate, sweet vanilla), 5‐ethylfurfural (caramel, spicy), 2,3‐dihydro‐3,5‐dihydroxy‐6‐methyl‐4H‐pyran‐4‐one (caramel), phenyl acetaldehyde (honey‐like), ethanone, 1‐(4‐hydroxy‐3‐methoxyphenyl) (faint vanilla)] were elucidated as important contributors to the overall chocolate, sweet vanilla, butterscotch aroma of the oil. CONCLUSION: Odorants with high concentrations in the roasted tigernut oil such as 5‐hydroxymethylfurfural, ethyl hexadecanoate, n‐propyl‐9,12‐octadecadienoate gave relatively low OAVs, so their contributions to the overall orthonasal aroma impression of roasted tigernut oil can be assumed to be low. © 2012 Society of Chemical Industry     

Stability of Cardamom (Elettaria Cardamomum) Essential Oil in Microcapsules Made of Whey Protein Isolate,Guar Gum,and Carrageenan

The effects of microencapsulating cardamom essential oil (CEO) in whey protein isolate (WPI) alone and combined with guar gum (GG) and carrageen (CG) on microencapsulation efficiency, oil chemical stability, and microcapsule structure were investigated. Freeze‐dried microcapsules were prepared from emulsions containing (w/w): 15% and 30% WPI; 0.1% GG, and 0.2% CG as wall materials with CEO (at 10% of polymer concentration) as core material, and physical properties and chemical stability were compared. Bulk density of microcapsules was highest in WPI without GG or CG and in 30% WPI + GG microcapsules, and was more affected by moisture content (r = ?0.6) than by mean particle diameter (d₄₃; r = ?0.2) and span (r = 0.1). Microcapsules containing only WPI had the highest entrapped oil (7.5%) and microencapsulation efficiency (98.5%). The concentrations of 1,8‐cineole and d‐limonene were used as indicators for microcapsule chemical stability since they were the main components of CEO. Microcapsules retained higher (P ≤ 0.05) concentrations of both components than non‐microencapsulated CEO during 16 wk storage at 20 ºC, but higher loss of both components was noted at 35 ºC. Microencapsulated d‐limonene was reduced faster than 1,8‐cineole regardless of temperature. The 30% WPI and 30% WPI + GG microcapsules retained CEO best throughout storage at both storage temperatures. Scanning electron micrographs revealed that WPI microcapsules had smooth surfaces, were relatively homogenous and regular in shape, whereas GG and CG addition increased visual surface porosity and reduced shape regularity. It was concluded that the best formulation for encapsulating CEO was 30% WPI.     

Effectiveness of synthetic and potential natural antioxidants in improving the stability of sheep's anhydrous butter fat during long-term storage

Sheep's anhydrous butter fat as prepared by including separately heat grits, turmeric, rosemary, sage, rue and fennel at a level of 75 g dry matter kg^?1 butter. The product as stored at room temperature in clear glass jars for a period of one year. The storage stabilities of the anhydrous butter fat samples ere compared ith a control and ith a sample treated ith a 1:1 mixture of BHA and BHT at a level of 0.25 g kg^?1. Both storage time and type of treatment had highly significant effects (P?0.01) on the peroxide value and free fatty acid content of the product. None of the treatments succeeded in keeping the peroxide value belo 5 mEq O₂ kg^?1 beyond the fourth month of storage. The BHA-BHT mixture and rosemary helped extend the peroxide induction period to 10 and 6 months respectively. Turmeric and heat grits ere as effective as BHA-BHT in controlling the oxidative rancidity during the first four months of storage. The rest of the herbs exhibited a pro-oxidant effect throughout the study hen they ere used separately. In a second experiment, some cases of positive synergistic interactions ere observed beteen turmeric and heat grits on one hand and the herbs used in the study on the other. This pattern as not regular as negative interactions ere also observed in some other cases. Free fatty acid content of all the samples remained belo 10 g kg^?1 as oleic acid; hoever, fennel had a significant (P?0.05) effect on controlling the evolution of free fatty acids.     

Oregano: chemical analysis and evaluation of its antimalarial, antioxidant, and cytotoxic activities

Abstract: GC‐FID and GC‐MS analysis of essential oil from oregano leaves (Origanum compactum) resulted in the identification of 46 compounds, representing more than 98% of the total composition. Carvacrol was the predominant compound (36.46%), followed by thymol (29.74%) and p‐cymene (24.31%). Serial extractions with petroleum ether, ethyl acetate, ethanol, and water were performed on aerials parts of Origanum compactum. In these extracts, different chemical families were characterized: polyphenols (gallic acid equivalent 21.2 to 858.3 g/kg), tannins (catechin equivalent 12.4 to 510.3 g/kg), anthocyanins (cyanidin equivalent 0.38 to 5.63 mg/kg), and flavonoids (quercetin equivalent 14.5 to 54.7 g/kg). The samples (essential oil and extracts) were subjected to a screening for antioxidant (DPPH and ABTS assays) and antimalarial activities and against human breast cancer cells. The essential oil showed a higher antioxidant activity with an IC₅₀= 2 ± 0.1 mg/L. Among the extracts, the aqueous extract had the highest antioxidant activity with an IC₅₀= 4.8 ± 0.2 mg/L (DPPH assay). Concerning antimalarial activity, Origanum compactum essential oil and ethyl acetate extract showed the best results with an IC₅₀ of 34 and 33 mg/mL, respectively. In addition, ethyl acetate extract (30 mg/L) and ethanol extract (56 mg/L) showed activity against human breast cancer cells (MCF7). The oregano essential oil was considered to be nontoxic.     

肉桂精油对红提葡萄保鲜效果的影响

目的：探究肉桂精油保鲜液在红提葡萄贮藏过程中的保鲜效果。方法：以新鲜红提葡萄为实验对象,在不同的温度和相对湿度条件下,采用不同体积分数的肉桂精油保鲜液对红提葡萄进行处理,并根据烂果率变化找出较优的贮藏条件和肉桂保鲜液体积分数,研究在较优贮藏环境下红提葡萄的风味品质（葡萄糖、可滴定酸）、质构品质（水分含量、硬度）及货架品质（烂果率、质量损失率、呼吸强度）的变化规律。结果：红提葡萄经过0.1%（N-0.1%）、0.5%（N-0.5%）和1.0%（N-1.0%）的肉桂保鲜液处理后发现,2 ℃条件下的红提葡萄烂果率比10 ℃好,而N-1.0%组红提葡萄的烂果率最低,保存效果最理想。通过2 ℃ 3 种相对湿度（50%、70%、90%）条件下品质的测定发现,90%的相对湿度环境更有利于肉桂保鲜液的抑菌保鲜效果。除烂果率低外,在贮藏末期红提葡萄的可滴定酸、葡萄糖、水分含量及硬度都保持在较高水平,分别为1.31%、10.78%、80.68%、1 003 g。同时,红提葡萄的质量损失率和呼吸强度也得到了有效抑制。结论：肉桂精油保鲜液的抑菌保鲜作用在低温、高湿条件下发挥更充分,较高体积分数的保鲜液保鲜效果较好,可以延缓红提葡萄贮藏品质的下降,延长贮藏时间。