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1.
Ginger, black pepper, and chili powder were extracted using near-critical carbon dioxide, propane, and dimethyl ether on a laboratory scale to determine the overall yield and extraction efficiency for selected pungent components. The temperature dependency of extraction yield and efficiency was also determined for black pepper and chili using propane and dimethyl ether. The pungency of the extracts was determined by using an NMR technique developed for this work. The volatiles contents of ginger and black pepper extracts were also determined. Extraction of all spice types was carried out with acetone to compare overall yields. Subcritical dimethyl ether was as effective at extracting the pungent principles from the spices as supercritical carbon dioxide, although a substantial amount of water was also extracted. Subcritical propane was the least effective solvent. All solvents quantitatively extracted the gingerols from ginger. The yields of capsaicins obtained by supercritical CO(2) and dimethyl ether were similar and approximately double that extracted by propane. The yield of piperines obtained by propane extraction of black pepper was low at approximately 10% of that achieved with dimethyl ether and CO(2), but improved with increasing extraction temperature.  相似文献   

2.
A total of 244 samples of cereals (wheat flour, rice, and maize), pulses (arhar, moong, gram, lentil, and black gram), spices (turmeric, chili, coriander, and black pepper), vegetables (potato, onion, spinach, cabbage, brinjal, and tomato), fruits (mango, guava, apple, and grape), milk, butter, Deshi ghee, and edible oils (vegetable, mustard, groundnut, and sesame) collected from different cities of Northern Province (Utter Pradesh) were analyzed by gas liquid chromatography for the presence of organochlorine pesticide residues. Residues of hexachlorocyclohexane (HCH) and 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) were detected in about 85% of the total samples of cereals, spices, milk, butter, Deshi ghee, and edible oils analyzed in the present study. However, the residue levels were either very small (less than 0.06 ppm) or not detected at all in pulses, vegetables, and fruits as compared with very high concentrations in wheat flour (4.42 and 0.12 ppm), butter (1.19 and 4.85 ppm), mustard oil (1.26 and 2.42 ppm), Deshi ghee (1.10 and 3.84 ppm), vegetable oil (1.02 and 0.59 ppm), groundnut oil (0.51 and 1.49 ppm), and chili (0.48 and 1.92 ppm). The levels of HCH and DDT residues detected in rice, maize, turmeric, corlander, black pepper, and all the vegetables and fruits were also lower than those found in wheat flour, oil, and fat samples analyzed in the present study. These findings suggest that a restricted and controlled use of such persistent pesticides may be useful for decreasing their contamination levels in different food items.  相似文献   

3.
Total equivalent antioxidant capacity (TEAC) and phenolic content of 26 common spice extracts from 12 botanical families were investigated. Qualitative and quantitative analyses of major phenolics in the spice extracts were systematically conducted by reversed-phase high-performance liquid chromatography (RP-HPLC). Many spices contained high levels of phenolics and demonstrated high antioxidant capacity. Wide variation in TEAC values (0.55-168.7 mmol/100 g) and total phenolic content (0.04-14.38 g of gallic acid equivalent/100 g) was observed. A highly positive linear relationship (R2= 0.95) obtained between TEAC values and total phenolic content showed that phenolic compounds in the tested spices contributed significantly to their antioxidant capacity. Major types of phenolic constituents identified in the spice extracts were phenolic acids, phenolic diterpenes, flavonoids, and volatile oils (e.g., aromatic compounds). Rosmarinic acid was the dominant phenolic compound in the six spices of the family Labiatae. Phenolic volatile oils were the principal active ingredients in most spices. The spices and related families with the highest antioxidant capacity were screened, e.g., clove in the Myrtaceae, cinnamon in the Lauraceae, oregano in the Labiatae, etc., representing potential sources of potent natural antioxidants for commercial exploitation. This study provides direct comparative data on antioxidant capacity and total and individual phenolics contents of the 26 spice extracts.  相似文献   

4.
A microbiological survey was performed on 4 selected imported spices: black peppercorns, white peppercorns, coriander, and fennel seed. Aerobic plate count values ranged from 10(4) to 10(7) colony-forming units (CFU)/g for black and white peppercorns and from 10(3) to 10(5) CFU/g for coriander and fennel seed. Combined results of the 3-tube most probable number procedure and the API 20E kit indicated the presence of Escherichia coli in 4 test samples of black peppercorns, 1 test sample of white peppercorns, and 1 test sample of coriander. Two test samples of black peppercorns were positive for Salmonella contamination. Among the various Enterobacteriaceae isolated from the spices, Enterobacter cloacae and Klebsiella pneumoniae were found most frequently in all spice types. Of 18 mammalian and avian fecal pellets removed from the spices and analyzed microbiologically, E. coli was found in only 2 pellet specimens. There was no apparent relationship between the enteric microflora found in spices and those found in the fecal pellets.  相似文献   

5.
Usually spices are identified morphologically using simple methods like magnifying glasses or microscopic instruments. On the other hand, molecular biological methods like the polymerase chain reaction (PCR) enable an accurate and specific detection also in complex matrices. Generally, the origins of spices are plants with diverse genetic backgrounds and relationships. The processing methods used for the production of spices are complex and individual. Consequently, the development of a reliable DNA-based method for spice analysis is a challenging intention. However, once established, this method will be easily adapted to less difficult food matrices. In the current study, several alternative methods for the isolation of DNA from spices have been developed and evaluated in detail with regard to (i) its purity (photometric), (ii) yield (fluorimetric methods), and (iii) its amplifiability (PCR). Whole genome amplification methods were used to preamplify isolates to improve the ratio between amplifiable DNA and inhibiting substances. Specific primer sets were designed, and the PCR conditions were optimized to detect 18 spices selectively. Assays of self-made spice mixtures were performed to proof the applicability of the developed methods.  相似文献   

6.
α-乙酰乳酸脱羧酶在啤酒生产中能加快啤酒成熟,有重要的应用价值。本研究将枯草芽孢杆菌启动子P43克隆到质粒pUC19-ALDC中的α-乙酰乳酸脱羧酶基因之前,得到重组质粒pUC19-P43-ALDC。重组质粒pUC19-P43-ALDC与质粒pMLK83-BN同源重组,筛选得到枯草芽孢杆菌整合质粒pMLK83-ALDC。用此整合质粒转化枯草芽孢杆菌1A751,挑选出新霉素抗性且无淀粉酶活性的重组菌株。此菌株用LB培养基在37℃、220r/min摇瓶培养过夜,测得α-乙酰乳酸脱羧酶活力为15.6U/mL,说明整合的α-乙酰乳酸脱羧酶基因能够在重组菌株中稳定传代和表达。本研究首次在枯草芽孢杆菌中用整合型的方式重组表达了α-乙酰乳酸脱羧酶,提出了一种有潜力的生产α-乙酰乳酸脱羧酶的新方法。  相似文献   

7.
Vitamin E was determined by the high-performance liquid chromatography (HPLC) method. All the plants tested showed differences in their alpha-tocopherol content and the differences were significant (p < 0.05). The highest alpha-tocopherol content was in Sauropus androgynus leaves (426.8 mg/kg edible portion), followed by Citrus hystrix leaves (398.3 mg/kg), Calamus scipronum (193.8 mg/kg), starfruit leaves Averrhoa belimbi (168.3 mg/kg), red pepper Capsicum annum (155.4 mg/kg), local celery Apium graveolens (136.4 mg/kg), sweet potato shoots Ipomoea batatas (130.1 mg/kg), Pandanus odorus (131.5 mg/kg), Oenanthe javanica (146.8 mg/kg), black tea Camelia chinensis (183.3 mg/kg),papaya Carica papaya shoots (111.3 mg/kg), wolfberry leaves Lycium chinense (94.4 mg/kg), bird chili Capsicum frutescens leaves (95.4 mg/kg), drumstick Moringa oleifera leaves (90.0 mg/kg), green chili Capsicum annum (87 mg/kg), Allium fistulosum leaves (74.6 mg/kg), and bell pepper Capsicum annum (71.0 mg/kg). alpha-Tocopherol was not detected in Brassica oleracea, Phaeomeria speciosa, Pachyrrhizus speciosa, Pleurotus sajor-caju, and Solanum melongena.  相似文献   

8.
9.
辣椒干储藏是干辣椒生产、贸易、消费中的一个重要环节,为给辣椒干的经营者和消费者提供参考依据和科学指导,本研究以线辣椒品种(系)“L14”和“陕椒2006”为试材,在冷藏、常温遮光,常温不遮光条件下储藏8个月,定期观测其主要品质性状的变化。结果表明:“L14”和“陕椒2006”果实中的辣椒素、辣椒红色素、维生素C和可溶性蛋白质的含量均随着储藏时间的延长而下降,其中前3种物质的保存率均为冷藏> 常温遮光> 常温不遮光,可溶性蛋白质的保存率为常温遮光>常温不遮光>冷藏;可溶性糖的含量则随着储藏时间的延长而缓慢上升,其增加率两品种(系)均为常温不遮光>常温遮光>冷藏。对试验数据两两进行配对T检验,发现温度对储藏期间辣椒素、维生素C含量的影响达到显著水平,对其他指标的影响不显著;光对辣椒红色素、维生素C含量的影响达到显著水平,对其他指标的影响不显著。综合各品质指标考虑,低温、遮光是辣椒干储藏的理想方式。  相似文献   

10.
An obscure sesquiterpene, rotundone, has been identified as a hitherto unrecognized important aroma impact compound with a strong spicy, peppercorn aroma. Excellent correlations were observed between the concentration of rotundone and the mean 'black pepper' aroma intensity rated by sensory panels for both grape and wine samples, indicating that rotundone is a major contributor to peppery characters in Shiraz grapes and wine (and to a lesser extent in wine of other varieties). Approximately 80% of a sensory panel were very sensitive to the aroma of rotundone (aroma detection threshold levels of 16 ng/L in red wine and 8 ng/L in water). Above these concentrations, these panelists described the spiked samples as more 'peppery' and 'spicy'. However, approximately 20% of panelists could not detect this compound at the highest concentration tested (4000 ng/L), even in water. Thus, the sensory experiences of two consumers enjoying the same glass of Shiraz wine might be very different. Rotundone was found in much higher amounts in other common herbs and spices, especially black and white peppercorns, where it was present at approximately 10000 times the level found in very 'peppery' wine. Rotundone is the first compound found in black or white peppercorns that has a distinctive peppery aroma. Rotundone has an odor activity value in pepper on the order of 50000-250000 and is, on this criterion, by far the most powerful aroma compound yet found in that most important spice.  相似文献   

11.
  【目的】   比较不同辣椒品种植株Cd的吸收和积累动态差异,明确Cd积累关键期,为生产上规避辣椒Cd积累提供技术支持。   【方法】   以8个辣椒品种为材料进行了田间小区试验,供试土壤全镉含量为0.194 mg/kg。在辣椒苗期 (移栽当天)、壮苗期 (移栽后32 天)、结果期 (移栽后65 天)、成熟期 (移栽后111天) 采样,分析辣椒植株根、茎、叶及果实生物量、Cd含量,计算不同组织间的Cd运转系数。   【结果】   供试8个品种分为菜椒和朝天椒两类。4次采集的样品,叶部Cd含量均为菜椒 > 朝天椒,果实Cd含量在结果期菜椒高于朝天椒,成熟期朝天椒显著高于菜椒。朝天椒果实以品种艳椒425的Cd含量最低,菜椒以品种苏椒5号Cd含量最低。壮苗期为辣椒植株Cd的快速积累期,朝天椒根、茎和叶Cd含量移栽后0到32天分别增加了14.9、51.2和51.9倍,菜椒分别增加了8.9、25.6和39.9倍。结果期Cd积累变缓,移栽后65天朝天椒根、茎和叶Cd含量比移栽后32 天分别增加了0.35、0.55和–0.13倍,菜椒分别增加了0.20、0.01和–0.29倍;成熟期 (移栽后111 天) 朝天椒根、茎和叶Cd含量比结果初期 (移栽后65天) 分别增加了–0.29、0.44和–0.40倍,菜椒分别增加了–0.34、–0.14和–0.32倍。不同辣椒品种Cd在植株内的转运能力有差异,4次采样根–茎Cd转运效率菜椒 > 朝天椒,而茎–叶、叶–果和茎–果Cd转运效率则是朝天椒 > 菜椒。辣椒果实Cd积累量与壮苗期茎的Cd含量呈极显著正相关 (P < 0.01),与茎–果、叶–果Cd转运效率显著相关 (P < 0.05)。   【结论】   壮苗期前 (移栽后0~32天) 为辣椒植株Cd的快速积累期,该时期辣椒根茎叶中的Cd含量可以增加数十倍,进入结果期Cd含量的增加速率大大降低。壮苗期辣椒茎的Cd含量与果实Cd积累量呈极显著相关。菜椒根中的Cd向茎的转运能力较强,而朝天椒茎叶中的Cd向果实中转运能力较强,因而,朝天椒果实Cd积累能力高于菜椒。  相似文献   

12.
Four common food acidulants--amchur, lime, tamarind, and kokum--and two antioxidant spices--turmeric and onion--were examined for their influence on the bioaccessibility of beta-carotene from two fleshy and two leafy vegetables. Amchur and lime generally enhanced the bioaccessibility of beta-carotene from these test vegetables in many instances. Such an improved bioaccessibility was evident in both raw and heat-processed vegetables. The effect of lime juice was generally more pronounced than that of amchur. Turmeric significantly enhanced the bioaccessibility of beta-carotene from all of the vegetables tested, especially when heat-processed. Onion enhanced the bioaccessibility of beta-carotene from pressure-cooked carrot and amaranth leaf and from open-pan-boiled pumpkin and fenugreek leaf. Lime juice and the antioxidant spices turmeric and onion minimized the loss of beta-carotene during heat processing of the vegetables. In the case of antioxidant spices, improved bioaccessibility of beta-carotene from heat-processed vegetables is attributable to their role in minimizing the loss of this provitamin. Lime juice, which enhanced the bioaccessibility of this provitamin from both raw and heat-processed vegetables, probably exerted this effect by some other mechanism in addition to minimizing the loss of beta-carotene. Thus, the presence of food acidulants (lime juice/amchur) and antioxidant spices (turmeric/onion) proved to be advantageous in the context of deriving maximum beta-carotene from the vegetable sources.  相似文献   

13.
The effects of steam and irradiation treatments on the physicochemical properties (moisture content, pH, extractable yield, reducing sugar, soluble pigment, antioxidant activity, piperine, Hunter's color, and sensory attributes) and microbiological quality (total aerobic bacteria, coliforms, and yeasts and molds) of ground black pepper stored at refrigerated and room temperatures for 6 months were compared and evaluated. Irradiation resulted in a higher microbial reduction in pepper, with minimal effects on the proximate composition, functional components, color, and sensory attributes of the spice. Steamed peppers appeared darker, and a considerable decrease in the piperine content was observed after treatment and storage. This study illustrates that irradiation is a better decontamination method than steam treatment in eliminating microorganisms without apparently affecting the quality of the powdered spice. Storage at 4 degrees C enhanced the microbial quality and minimized the loss of piperine content in ground black peppers.  相似文献   

14.
Nine spice and aromatic herb samples (i.e., basil, bird pepper, black pepper, cinnamon, nutmeg, oregano, parsley, rosemary, and sage) were gamma-irradiated at a dose of 10 kGy according to commercial practices. The effects of the disinfection treatment on the content of organic radicals and some nutrients (namely, vitamin C and carotenoids) in the samples were investigated by chromatographic and spectroscopic techniques. Irradiation resulted in a general increase of quinone radical content in all of the investigated samples, as revealed by electron paramagnetic resonance spectroscopy. The fate of these radicals after storage for 3 months was also investigated. The cellulose radical was clearly observed in a few samples. Significant losses of total ascorbate were found for black pepper, cinnamon, nutmeg, oregano, and sage, whereas a significant decrease of carotenoids content was observed for cinnamon, oregano, parsley, rosemary, bird pepper, and sage.  相似文献   

15.
The oxidation of low-density lipoprotein (LDL) is believed to be the initiating factor for the development and progression of atherosclerosis. The active ingredients of spices such as chili and turmeric (capsaicin and curcumin, respectively) have been shown to reduce the susceptibility of LDL to oxidation. One of the techniques used to study the oxidation of LDL is to isolate LDL and subject it to metal-induced (copper or iron) oxidation. However, whole serum may represent a closer situation to in vivo conditions than using isolated LDL. We investigated the effects of different concentrations (0.1-3 microM) of capsaicin, dihydrocapsaicin, and curcumin on copper-induced oxidation of serum lipoproteins. The lag time (before initiation of oxidation) and rate of oxidation (slope of propagation phase) were calculated. The lag time increased, and the rate of oxidation decreased with increasing concentrations of the tested antioxidants (p < 0.05). A 50% increase in lag time (from control) was observed at concentrations between 0.5 and 0.7 microM for capsaicin, dihydrocapsaicin, and curcumin. This study shows that oxidation of serum lipids is reduced by capsaicinoids and curcumin in a concentration-dependent manner.  相似文献   

16.
为增强氨杀灭土壤病原微生物、防控作物土传病害的效果,采用室内培养和盆栽试验的方法,研究了硝化抑制剂DMPP和(或)碳酸氢铵预处理潮土15 d,对土壤理化性质和土壤细菌、真菌、氨氧化菌、辣椒疫霉菌数量的影响以及对辣椒疫病的防效,并对辣椒疫病的发病率与土壤理化及微生物学性状进行相关性分析,为开发新的防控辣椒疫病的技术提供依据。结果表明,施加DMPP的土壤铵态氮含量显著高于对照,而土壤pH、硝态氮和亚硝态氮含量显著低于对照。碳酸氢铵和DMPP配合施用处理土壤15 d,土壤细菌amo A基因拷贝数和辣椒疫霉菌ITS基因拷贝数分别降低34.9%(P0.05)和93.8%(P0.05);土壤16S r RNA基因拷贝数比未添加DMPP处理高出54.7%(P0.05);DMPP对土壤氨氧化古菌amo A基因拷贝数无显著影响。栽植辣椒28 d后,DMPP和碳酸氢铵配合施用处理的辣椒疫霉菌ITS基因拷贝数最低(2.1×10~5 copies·g~(-1)),其次为DMPP(15.4×10~5 copies·g~(-1));对照辣椒根际疫霉数量最高(37.1×10~5 copies·g~(-1)),分别比碳酸氢铵处理、DMPP处理和DMPP和碳酸氢铵配合施用处理高0.4倍、1.4倍和16.8倍。碳酸氢铵或DMPP处理过的土壤栽植辣椒28 d后,对照辣椒疫病发病率最高(95.00%),仅施用碳酸氢铵处理发病率次之(85.00%),DMPP和碳酸氢铵配合施用处理的发病率最低(32.20%),其防治效果达66.11%。辣椒疫病的发生率与土壤电导率、硝态氮含量、疫霉菌数量正相关,与土壤pH、铵态氮含量、细菌及真菌数量负相关。综上,碳酸氢铵和DMPP配合施用降低潮土氨氧化细菌的数量,从而增加铵态氮而降低硝态氮含量,提高了土壤pH,进而降低土壤疫霉菌数量,因而能有效防控辣椒疫病。  相似文献   

17.
Curcumin, the yellow color pigment of turmeric, is produced industrially from turmeric oleoresin. The mother liquor after isolation of curcumin from oleoresin contains approximately 40% oil. The oil was extracted from the mother liquor using hexane at 60 degrees C, and the hexane extract was separated into three fractions using silica gel column chromatography. These fractions were tested for antibacterial activity by pour plate method against Bacillus cereus, Bacillus coagulans, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Fraction II eluted with 5% ethyl acetate in hexane was found to be most active fraction. The turmeric oil, fraction I, and fraction II were analyzed by GC and GC-MS. ar-Turmerone, turmerone, and curlone were found to be the major compounds present in these fractions along with other oxygenated compounds.  相似文献   

18.
In the present study the antioxidant, anticancer, and antimycobacterial activities of extracts from ginger (Zingiber officinale Roscoe), rosemary (Rosmarinus officinalis L.), and turmeric (Curcuma longa L.) were evaluated. The extracts were obtained using supercritical CO(2) with and without ethanol and/or isopropyl alcohol as cosolvent. The extracts' antioxidant power was assessed using the reaction between beta-carotene and linolenic acid, the antimycobacterial activity against M. tuberculosis was measured by the MABA test, and their anticancer action was tested against nine human cancer ancestries: lung, breast, breast resistant, melanoma, colon, prostate, leukemia, and kidney. The rosemary extracts exhibited the strongest antioxidant and the lowest antimycobacterial activities. Turmeric extracts showed the greatest antimycobacterial activity. Ginger and turmeric extracts showed selective anticancer activities.  相似文献   

19.
The pungent compounds piperine and isomers thereof, secondary metabolites present in black and white pepper fruit, undergo light-induced isomerizations. To facilitate studies in this area, an HPLC method has been developed for analysis and isolation of the following four possible piperine-derived photoinduced isomers: piperine, isopiperine, chavicine, and isochavicine. The limits of detection (LOD) estimated from calibration plots were approximately 15-30 ng for each isomer. Reproducibilities of the analyses were excellent, and recoveries of spiked samples were as follows (average +/- SD; n = 3): chavicine, 98.4 +/- 2.1%; isopiperine, 96.2 +/- 3.2%; piperine, 104 +/- 3.8%; isochavicine, 98.9 +/- 3.0%. To determine the kinetics of these isomerizations, fluorescent light, sunlight, and UV radiation at 254 nm was used to induce cis-trans geometric isomerization as a function of light intensities and time of exposure determined with the aid of high-performance liquid chromatography (HPLC) and liquid chromatography with diode array UV detection-mass spectrometry (LC-DAD/MS). HPLC was also used to determine the distribution of the isomers in four commercial ground black pepper products used as spices in culinary practice. Isomerization increased with light intensities and time of exposure and leveled off at the so-called photostationary phases. The piperine levels of the four products were quite similar, ranging (in wt %) from 10.17 to 11.68. The amounts of the other three isomers ranged from 0.01 to 0.07 of the total for chavicine; from 0.15 to 0.23 for isopiperine; and from 0.37 to 0.42 for isochavicine. The results establish the utility of the HPLC method for simultaneous analysis of the four isomers both in pure form and in black pepper extracts. The dietary significance of the results is discussed.  相似文献   

20.
辐照香料与食品的鉴定   总被引:1,自引:0,他引:1  
本文采用ESR和化学发光等测量法鉴定辐照香料和辐照食物,研究了花椒粉、胡椒粉(黑、白)、大料、姜粉、芥末、咖哩粉、安息茴香、五香粉、香辣酥和复合调料等香料,以及全脂奶粉、纯藕粉、健儿粉、白面粉、甘草霜和食用明胶等食物经60Coγ射线辐照后,ESR及化学发光强度的变化,以及辐照剂量,贮藏时间和样品粒度对ESR及化学发光的影响。结果表明,两种方法均可有效地区分辐照和未辐照食物和香料,而ESR法较化学发光法更易应用,其鉴定的有效期在30天以上。此外,还对某些包装材料如玻璃、木材和纸等的ESR变化规律进行了初步研究。  相似文献   

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