枸杞多糖对LPS诱导BV2小胶质细胞的抗炎活性及NF-κB信号通路的调控作用

为探究枸杞多糖（Lycium barbarum polysaccharide,LBP）对脂多糖（lipopolysaccharide,LPS）诱导的BV2小胶质细胞的保护作用。本研究利用MTT法检测细胞活性,ELISA检测炎症因子的分泌,Western Blot检测蛋白表达情况。结果显示,单独LPS处理BV2小胶质细胞后,细胞的活性无显著变化而细胞上清液中的炎症因子PGE2、IL-1β、IL-6及TNF-α释放显著增多;将枸杞多糖梯度与LPS诱导的BV2小胶质细胞共孵育24 h后,有效地提升了LPS诱导的BV2小胶质细胞的活性,同时显著抑制了LPS激活的BV2小胶质细胞炎症因子的释放（P<0.05）;流式结果表明,LPS组小胶质细胞可产生大量ROS,小胶质细胞经不同浓度LBP处理12 h后,ROS含量显著降低（P<0.05）;Western Blot检测结果显示,与对照组相比,LPS组和LBP组中NF-κB信号通路相关蛋白表达及细胞核内p65蛋白表达水平均显著上调（P<0.05）,且与LBP浓度成反比,而细胞质内p65蛋白表达显著降低（P<0.05）,且随着LBP浓度增加而降低。本研究表明,枸杞多糖对LPS激活的BV2小胶质细胞有显著的保护作用,对于LPS激活的BV2小胶质细胞引起的炎症反应具有抑制作用,同时能抑制小胶质细胞中ROS的含量以发挥抗氧化应激作用,同时有效地抑制LPS刺激后细胞内p-TAK1、iκB、p-iκB及p-p65的表达。     

无溶剂微波萃取肉桂精油及成分分析

优化无溶剂微波萃取肉桂油的工艺条件,结合气相色谱质谱联用仪进行肉桂油成分鉴定,同时探究该工艺提取肉桂精油的体外抗氧化能力和肉桂表面微观形貌,并与水蒸气蒸馏法萃取肉桂油进行对比。以肉桂精油得率为评价指标,通过正交试验得出最佳试验条件,提取时间60 min、微波功率450 W、含水率60%、浸润时间2.5 h;在该试验条件下的肉桂精油得率为3.15%,较传统的水蒸气蒸馏法提高了35.78%;采用气相色谱质谱联用仪对肉桂精油进行成分分析,并通过质谱库与保留指数验证,从无溶剂微波工艺萃取的肉桂精油中共鉴定出了24种化合物,主要包括肉桂醛(67.69%)、丁香酚(11.36%)、芳樟醇(4.26%)、柠檬烯(2.40%)等,且肉桂醛及柠檬烯的含量较水蒸气蒸馏萃取肉桂油分别提高了14.49%和34.51%,表明无溶剂微波萃取肉桂油有更高的药理活性;扫描电子显微镜SEM观察到无溶剂微波萃取后的肉桂样品有明显的空隙和大量不规则的空腔结构;无溶剂微波萃取肉桂油对DPPH自由基和羟基自由基的清除作用的IC50分别为,2.10 mg/mL和0.17 mg/mL,优于传统水蒸气蒸馏法萃取肉桂油;综上,无溶剂微波萃取工艺是种较理想的提取肉桂精油的方法,具有提取效率高、肉桂精油得率高及品质优良等优点。     

Anti-neuroinflammatory effects of geranium oil in microglial cells

Microglial cells are major immune cells in the brain, and their activation is involved in neurodegenerative diseases such as Alzheimer’s disease. Activated microglial cells secrete proinflammatory factors including nitric oxide (NO), which is an important mediator of neuroinflammation and neuronal cell death. In the present study, we demonstrated that geranium oil inhibited NO production, as well as the expression of the proinflammatory enzymes cyclooxygenase-2 (COX-2) and induced nitric oxide synthase (iNOS) in primary cultures of activated microglial cells. When tested at their natural relative concentrations in the oil, none of the major constituents of the oil could inhibit NO production. However, at higher concentrations, citronellol exhibited an inhibitory activity. The results suggest a possible synergistic interaction between these components. Thus, geranium oil might be beneficial in the prevention/treatment of neurodegenerative diseases where neuroinflammation is part of the pathophysiology.     

丁香和肉桂挥发油的提取、主要成分测定及其抗菌活性研究

本文采用水蒸汽蒸馏法提取丁香和肉桂的挥发油,并对所得挥发油主要成分进行气相测定,通过体外抗菌试验,比较了这两种挥发油及其主要成分和目前常用化学防腐剂苯甲酸钠和山梨酸钾对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌、沙门氏菌和志贺氏菌等5株食品中常见污染菌的抗菌作用。结果表明丁香油中丁香酚含量为78.1%,肉桂油中肉桂醛含量为86.8%;这两种挥发油及其主要成分丁香酚和肉桂醛的抗菌作用均强于两种化学防腐剂,其中肉桂油与其主要成分肉桂醛表现出的抗菌活性最强,最小抑菌浓度(MIC)为200～1600mg/L;仅为苯甲酸钠和山梨酸钾MIC(6400～25600mg/L)的1/64～1/16;丁香油及其主要成分丁香酚的抗菌活性次之,MIC为800～1600mg/L,相当于苯甲酸钠和山梨酸钾MIC的1/16～1/8。     

采收月份对肉桂叶出油率及挥发油品质的影响研究

目的:以肉桂叶挥发油主要成分肉桂醛的含量及其抑菌活性作为衡量肉桂叶挥发油品质的两个指标,比较不同采收月份肉桂叶出油率及挥发油品质的差异。方法:采用水蒸气蒸馏法提取肉桂叶挥发油,通过气相色谱-质谱技术比较分析其化学成分,用归一化法测定其相对百分含量,并采用微量肉汤稀释法测定MIC评价各肉桂叶挥发油对常见的3种致病菌的抑菌活性。结果:10月份采收的肉桂叶挥发油含量最高(1.51%),6月份采收的肉桂叶挥发油含量最低(0.42%)。12份肉桂叶挥发油共鉴定出32种组分,共有组分为反式肉桂醛(21.37%~86.46%)、邻甲氧基肉桂醛(1.08%~12.46%)、苯甲醛(0.16%~2.40%)、顺式肉桂醛(0.18%~0.82%)。除7月份采收的肉桂叶挥发油外,反式肉桂醛均为挥发油中含量最高的组分,7月肉桂叶挥发油中含量最高的组分为乙酸肉桂酯(47.06%)。12份肉桂叶挥发油对大肠杆菌的抑菌效果最好,对绿脓杆菌的抑菌效果最弱。其中5月采收的肉桂叶挥发油对3种供试菌的抑制作用最好。结论:肉桂叶的采收月份宜在春季3月下旬至5月上旬和秋季9月下旬至11月上旬。     

Optimization of green extraction methods for cinnamic acid and cinnamaldehyde from Cinnamon (<Emphasis Type="Italic">Cinnamomum cassia</Emphasis>) by response surface methodology

The major compounds of cinnamon are cinnamic acid and cinnamaldehyde, for which the conditions of microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and reflux extraction (RE) were optimized using response surface methodology for comparing their efficiencies in terms of extraction yield, consumption of time and energy, and CO₂ emission. The results indicated MAE superiority to UAE and RE owing to the highest yield of target compounds (total yield: 0.89%, cinnamic acid: 6.48 mg/100 mL, and cinnamaldehyde: 244.45 mg/100 mL) at optimum MAE conditions: 59% ethanol, 147.5 W microwave power and 3.4 min of extraction time. RE resulted in comparable yields with the highest consumption of time, energy, and solvent, and least CO₂ emission. Therefore, it is concluded that MAE is the most efficient method for green extraction of cinnamic acid and cinnamaldehyde from cinnamon powder compared to UAE and RE.     

Attenuation of iNOS and COX2 by blueberry polyphenols is mediated through the suppression of NF-κB activation

Treatment of BV2 microglial cells with blueberry extracts has been shown to be effective in reducing lipopolysaccharide (LPS)-induced proinflammatory mediators such as nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), inducible NO synthase (iNOS), and cyclooxygenase 2 (COX2). The current study explored the possibility that the down-regulation of iNOS and COX2 by blueberry extracts was mediated through NF-κB signaling pathway. A column-purified fraction of polyphenol-enriched blueberry extract (PC18) was used to treat LPS-activated BV2 cells. The results thus far showed that blueberry polyphenols significantly suppressed iNOS and COX2 promoter activities. In addition, blueberry polyphenols inhibited NF-κB nuclear translocation in LPS-activated BV2 cells. These findings suggested that the beneficial effects of blueberries may involve direct modulation of oxidative stress and/or inflammatory signaling cascades.     

肉桂油对蛋清蛋白/可得然胶凝胶理化特性及释放肉桂醛性能的影响

卤制工艺中风味组分的控制释放有望对卤制品品质的工业标准化程度进行调控。以蛋清蛋白和可得然胶为基质材料,以肉桂油为风味组分代表,水油两相均质后通过热诱导法制备乳液凝胶,探究肉桂油添加对乳液凝胶特性及释放肉桂醛性能的影响。结果表明,与大豆油乳液凝胶相比,肉桂油乳液凝胶颜色偏黄,微观结构更加致密,持水率、硬度、储能模量和损耗模量等参数显著增加,且当肉桂油质量分数为5%时凝胶性能最强。随着肉桂油添加量的增加,凝胶转变时间缩短,同时乳液凝胶的黏弹性减弱,亮度增加、黄度降低。红外光谱证实了肉桂油中的肉桂醛与蛋清蛋白发生了席夫碱反应,从而促进乳液凝胶的形成及凝胶性能的提升。在模拟卤制品加工环境下,肉桂油乳液凝胶对所含肉桂醛具有良好的控释效果:水相中肉桂醛的释放率随肉桂油添加量的增加而减小,当肉桂油质量分数从5%增加至11%时,乳液凝胶在水中煮制1h后,肉桂醛的累积释放率降低35.44%;与在水中煮制相比,调味料氯化钠、醋酸与乙醇可促进水相中肉桂醛的释放,且在醋酸中的累积释放率增幅最大(15.95%);但模拟卤制基质中的蛋白质和多糖会抑制肉桂醛的释放,累积释放率降低9.58%以上。乳液凝胶在模拟食品加工过程中能维持原有块状形貌,但在酸性条件下质地变硬、体积缩小、损失率最大,且凝胶结构破坏程度最严重,促进了肉桂醛的释放。因此,蛋清蛋白/可得然胶乳液凝胶的质地与释放性能可通过肉桂油的活性填充进行调控。研究结果旨在为食品工业中风味控释技术的开发提供理论参考。     

Apple extracts attenuate tumor necrosis factor-α-induced nuclear factor-κB activation by inhibiting IκB kinase and proteasome in A549 human non-small lung carcinoma cells

Apples contain a variety of phytochemicals and health benefits of apple consumption are widely recognized in reducing the risks of chronic diseases such as cancer. However, the mechanisms of apples in inhibiting lung cancer cell proliferation are not fully understood. The present study examined the role of apple extracts in suppressing nuclear factor (NF)-κB activation in A549 human lung cancer cells. Incubation with apple extracts at doses of 10 and 20 mg(fresh apple)/mL significantly inhibited tumor necrosis factor (TNF)-α-induced NF-κB activation in A549 cells (p<0.05). Apple extracts suppressed phosphorylation of inhibitor of NF-κB (IκB-α) at doses of 10 and 20 mg (fresh apple)/mL and inhibited proteasomal activity at doses of 5, 10, and 20 mg(fresh apple)/mL (p<0.05). These results indicate that apple extracts inhibit TNF-α-induced NF-κB activation in A549 lung cancer cells by suppressing both of IκB kinase (IKK) activity and proteasomal activity.     

Nuclear translocation of NF-κB in intact human gut tissue upon stimulation with coffee and roasting products

In the healthy gut, NF-κB is a critical factor of the intestinal immune system, whereas inflammatory bowel diseases are associated with chronic activation of NF-κB. Previous studies indicated that coffee induces nuclear translocation of NF-κB in macrophages, an effect attributed to roasting products. In the present work, coffee extract or roasting products induced nuclear translocation of NF-κB in macrophages, Caco-2 cells, and primary human intestinal microvascular endothelial cells (up to fivefold, p<0.001). Since the effect clearly depended on the cell type, ex vivo experiments were performed with intact human gut tissue from biopsies. The uniformity of the specimens and tissue viability during ex vivo incubation for up to 2 h were verified. Roasting products led to a concentration dependent significant increase of nuclear translocation of NF-κB in human gut tissue (up to 2.85 fold increase, p=0.0321), whereas coffee extract induced a trend towards higher nuclear NF-κB concentration. NF-κB activation in macrophages and Caco-2 cells by roasting products was significantly blocked by co-incubation with catalase (p=0.011 and p=0.024) indicating involvement of H(2)O(2)-signaling. Monitoring of extracellular H(2)O(2) indicated that roasting products in coffee constantly generate H(2)O(2) by spontaneous oxygen reduction, which is only partially detoxified by cellular antioxidative systems. Thus, it can be concluded that ex vivo stimulation of intact human gut tissue is a valuable model to study nutritional effects on complex tissue systems. Furthermore, the consumption of coffee and roasting products may be able to induce nuclear NF-κB translocation in the human gut.     

Effective chemical control of psychrotrophic Bacillus cereus EPSO-35AS and INRA TZ415 spore outgrowth in carrot broth

The growth kinetic parameters of germinated cells from heat-activated spores of the psychrotrophic Bacillus cereus EPSO-35AS strain in nutrient broth (NB) and in tyndallized carrot broth (TCB) were evaluated at different temperatures (8, 12, and 16 degrees C) for control samples and for samples acidified with citric acid or lemon juice at pH values between 4.7 and 5.5. Lowering the pH from 7.4 or 6.2 to 5.2 inhibited bacterial growth in both tested media after 60 days at 12 degrees C and lower temperatures, confirming the effectiveness of acidification in association with refrigeration to control B. cereus proliferation in minimally processed foods (MPFs) based on carrot. The activities of selected concentrations of cinnamon essential oil, cinnamaldehyde, carvacrol, and eugenol against B. cereus EPSO-35AS and INRA TZ415 strains in both media over the same temperature range were also studied. Addition of either cinnamon essential oil or cinnamaldehyde at concentrations of 5 and 2 microL 100mL(-1), respectively, caused complete inhibition of the growth of both psychrotrophic strains even if mild temperature abuse occurred (12 degrees C). Hence, a combination of one of these compounds and refrigerated storage may be useful for preservation of MPFs in which major ingredient was carrot. On the contrary, carvacrol and eugenol were not able to prevent B. cereus growth in TCB during storage at 8 degrees C. Their effects on the organoleptic characteristics of TCB are discussed.     

Effect of nanoemulsion to minimise undesirable odour and colour of cinnamon bark oil and to improve sensory properties of refrigerated Asian seabass fillets

The use of cinnamon bark oil (CBO) to inhibit fish spoilage causes undesirable changes in sensory properties of fish fillets. This research prepared CBO nanoemulsion (CBON) and studied its effects on the volatile profile and sensory properties of Asian seabass fillets. Changes in volatile profile, colour and odour scores, and overall likeness scores of CBON-treated fillets were determined during storage in comparison to the control (CTRL) and bulk cinnamon bark oil (BCBO)-treated ones. After treatment, CBON and BCBO were able to mask the natural odour of fish fillets. However, CBON did not change the fillets' colour. During storage, CBON-treated fillets contained relatively higher cinnamaldehyde content and higher colour score but less cinnamon oil-like odour score than those of BCBO-treated ones. CBON-treated fillets also had higher acceptance scores than those of CTRL and BCBO-treated fillets after storage. These results demonstrated the efficiency of the nanoemulsion system to minimise undesirable effects of CBO and maintain sensory acceptance of the fillets during storage.     

Inactivation of Salmonella enterica serovar Typhimurium and Quality Maintenance of Cherry Tomatoes Treated with Gaseous Essential Oils

The antimicrobial activity of the essential oils (EOs) from cinnamon bark, oregano, mustard, and of their major components cinnamaldehyde, carvacrol, and allyl isothiocyanate (AIT) was evaluated as a gaseous treatment to reduce Salmonella enterica serovar Typhimurium in vitro and on tomatoes. In vitro tests showed that mustard EO and AIT had the greatest inhibition of Salmonella, followed by cinnamon EO and cinnamaldehyde, while oregano and carvacrol showed the least inhibition. Scanning electron microscopy images of S. Typhimurium on tomatoes suggest that the EOs and their major components damaged the bacteria, and the damage was more obvious after posttreatment storage at 10 °C for 4 and 7 d. Salmonella on inoculated tomatoes was reduced by more than 5 log colony forming units (CFU)/g by mustard EO and AIT, by 4.56 and 3.79 log CFU/g following cinnamon EO and cinnamaldehyde treatments, respectively, and 1.54 and 3.37 log CFU/g after oregano EO and carvacrol treatments, respectively. Mustard EO and AIT induced discoloration, softening, and loss of the vitamin C and lycopene during 21 d of storage at 10 °C, while treatment with cinnamon EO and cinnamaldehyde did not result in significant changes in tomato quality. Tomatoes treated with oregano EO had better quality than nontreated samples after storage. Therefore, treatment with cinnamon and oregano EO and their major components appeared to be feasible for inactivation of Salmonella on tomatoes and maintaining quality.     

Bactericidal activities of plant essential oils and some of their isolated constituents against Campylobacter jejuni,Escherichia coli,Listeria monocytogenes,and Salmonella enterica

An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was defined as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and allspice oils; those that were most active against L monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible significance of these results with regard to food microbiology is discussed.     

Aromatic‐Turmerone Attenuates LPS‐Induced Neuroinflammation and Consequent Memory Impairment by Targeting TLR4‐Dependent Signaling Pathway

Scope : Curcuma longa (turmeric) is a folk medicine in South and Southeast Asia, which has been widely used to alleviate chronic inflammation. Aromatic‐turmerone is one of the main components abundant in turmeric essential oil. However, little information is available from controlled studies regarding its biological activities and underlying molecular mechanisms against chronic inflammation in the brain. In the current study, we employed a classical LPS model to study the effect and mechanism of aromatic‐turmerone on neuroinflammation. Methods and results : The effects of aromatic‐turmerone were studied in LPS‐treated mice and BV2 cells. The cognitive function assays, protein analyses, and histological examination were performed. Oral administration of aromatic‐turmerone could reverse LPS‐induced memory disturbance and normalize glucose intake and metabolism in the brains of mice. Moreover, aromatic‐turmerone significantly limited brain damage, through inhibiting the activation of microglia and generation of inflammatory cytokines. Further study in vitro revealed that aromatic‐turmerone targeted Toll‐like receptor 4 mediated downstream signaling, and lowered the release of inflammatory mediators. Conclusion : These observations indicate that aromatic‐turmerone is effective in preventing brain damage caused by neuroinflammation and may be useful in the treatment of neuronal inflammatory diseases.     

香辛料提取物复配对风干肠品质和生物胺的影响

该文研究了风干肠中常用的3种香辛料(肉桂、丁香和八角)的提取物以不同方式复配对其发酵过程中生物胺、微生物、理化品质的影响。结果发现,复合香辛料提取物能够有效抑制风干肠发酵过程中常见的2-苯乙胺、腐胺、酪胺色胺、尸胺和组胺的积累(P<0.05),尤其是肉桂&丁香&八角复配组抑制效果最佳,其次为肉桂&八角,肉桂&丁香和丁香&八角组。复合香辛料提取物有效抑制了发酵过程中脂肪氧化产物(硫代巴比妥酸反应物)的增加,部分微生物(肠杆菌和好氧菌)的生长,同时改善了风干肠的感官品质,且各处理组中,肉桂&丁香&八角复配组的效果最优。综上,肉桂、丁香、八角3种香辛料的复合提取物添加到风干肠中可以抑制风干肠中生物胺的积累,改善其理化和感官品质。     

Antimicrobial Wine Formulations Active Against the Foodborne Pathogens Escherichia coli O157: H7 and Salmonella enterica

ABSTRACT:  We developed wine formulations containing plant essential oils and oil compounds effective against foodborne pathogenic bacteria Escherichia coli O157:H7 and Salmonella enterica. HPLC was used to determine maximum solubility of antimicrobials in wines as well as amounts of antimicrobials extracted by wines from commercial oregano and thyme leaves. Activity of essential oils (cinnamon, lemongrass, oregano, and thyme) and oil compounds (carvacrol, cinnamaldehyde, citral, and thymol) in wines were evaluated in terms of the percentage of the sample that resulted in a 50% decrease in the number of bacteria (BA₅₀). The ranges of activities in wines (30 min BA₅₀ values) against S. enterica/E. coli were carvacrol, 0.0059 to 0.010/0.011 to 0.021; oregano oils, 0.0079 to 0.014/0.022 to 0.031; cinnamaldehyde, 0.030 to 0.051/0.098 to 0.13; citral, 0.033 to 0.038/0.060 to 0.070; lemongrass oil, 0.053 to 0.066/0.059 to 0.071; cinnamon oil 0.038 to 0.057/0.066 to 0.098; thymol, 0.0086 to 0.010/0.016 to 0.022; and thyme oil, 0.0097 to 0.011/0.033 to 0.039. Detailed studies with carvacrol, the main component of oregano oil, showed that antibacterial activity was greater against S. enterica than against E. coli and that wine formulations exhibited high activities at low concentrations of added antimicrobials. The results suggest that wines containing essential oils/oil compounds, added or extracted from oregano or thyme leaves, could be used to reduce pathogens in food and other environments.     

Selected plant essential oils and their main active components,a promising approach to inhibit aflatoxigenic fungi and aflatoxin production in food

Recent research has showed that Aspergillus flavus and Aspergillus parasiticus are aflatoxigenic species that can become very competitive in the framework of climate change. Aflatoxins show carcinogenic, mutagenic, immunotoxic and teratogenic effects on human and animals. Effective and sustainable measures to inhibit these species and aflatoxins in food are required. Origanum vulgare and Cinnamomum zeylanicum essential oils (EOs) and their major active constituents, carvacrol and cinnamaldehyde, respectively, were assayed for inhibiting these species and aflatoxin production in maize extract medium under different environmental conditions. Doses of 10–1000 mg l^?1 were assayed and the effective doses for 50 (ED₅₀) and 90% (ED₉₀) growth inhibition were determined. The ED₅₀ of cinnamaldehyde, carvacrol, oregano EO, and cinnamon EO against A. flavus were in the ranges 49–52.6, 98–145, 152–505, 295–560 mg l^?1 and against A. parasiticus in the ranges 46–55.5, 101–175, 260–425 and 490–675 mg l^?1, respectively, depending on environmental conditions. In A. flavus treatments ED₉₀ were in the ranges 89.7–90.5, 770–860 and 820–>1000 mg l^?1 for cinnamaldehyde, carvacrol and cinnamon EO, and in A. parasiticus treatments in the ranges 89–91, 855–>1000 and 900–>1000 mg l^?1, respectively. ED₉₀ values for oregano EO against both species were >1000 mg l^?1. Growth rates of both species were higher at 37 than at 25°C and at 0.99 than at 0.96 a_w. Aflatoxin production was higher at 25 than at 37°C. Stimulation of aflatoxin production was observed at low doses except for cinnamaldehyde treatments. The effectiveness of EOs and their main constituents to inhibit fungal growth and aflatoxin production in contact assays was lower than in vapour phase assays using bioactive EVOH-EO films previously reported.     

Isoflavone content and apoptotic effect in HT-29 cancer cells of a soy germ extract

Colon cancer is one of the leading causes of death and a major public health problem in western countries. We examined the isoflavone content of 70% ethanol extract of soy germ (SG) and its apoptotic effect in HT-29 colon cancer cells. Our results showed that the major isoflavones of the SG extract were daidzein and genistein, and it effectively induced apoptosis in HT-29 cancer cells. In addition, nuclear factor-kappa B (NF-κB) expression was reduced in cells treated with the SG extract, which reduced cyclooxygenase-2 (COX-2) and nitric oxide synthase (iNOS) expression. These combined effects ultimately resulted in apoptosis via caspase-3 activation. In addition, daidzein and genistein, the major isoflavones of SG extract, also exerted the apoptotic effect against HT-29 cancer cells. These results suggest that the inhibition of NF-κB expression is the most important factor in the induction of apoptosis in HT-29 cells treated with the SG extract.