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41.
42.
Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use.  相似文献   
43.
Composite flours were prepared from blends of yellow maize (Zea mays), sesame seed (Sesamum indicum) and oyster mushroom (Pleurotus ostreatus) powder in the ratio of 80:20:0; 75:20:5; 70:20:10; 65:20:15 and 60:20:20, respectively to produce the cereal-based breakfast product coded as YSB, SMB, TMB, PMB and OMB with YSB as the control. The breakfast cereals were produced by hydration and toasting of yellow maize and sesame to 160°C for 25 min and blended together with oven-dried and packaged oyster mushroom. The developed products were analysed for proximate, vitamins, minerals and sensory properties. The proximate composition (%) of different blends ranged as moisture (4.07–7.08), ash (3.09–2.28), crude fat (16.04–12.83), crude fibre (4.30–8.22), protein (16.14–22.54), carbohydrate (56.34–47.04) and energy (434.34–393.83 Kcal). Vitamin A (7.99–5.98 mg/100 g), vitamin B1 (0.08–0.42 mg/100 g), vitamin B2 (0.06–0.15 mg/100 g), vitamin B3 (1.91–4.52 mg/100 g) and vitamin C (3.55–3.32 mg/100 g) were u while minerals (mg/100 g) were calcium (75.31–58.02), potassium (0.65–4.01), magnesium (12.25–12.62), iron (1.21–4.15) and zinc (0.40–1.32). Sensory scores revealed that the cereal-based breakfast product were acceptable to the panellist with oyster mushroom supplementation up to 10%.  相似文献   
44.

Objectives

California experienced a notable decline in per capita cigarette consumption during its comprehensive tobacco control programme. This study examines what proportion of the decline occurred from: (1) fewer ever smokers in the population, (2) more ever smokers quitting, and (3) current smokers smoking less.

Design, subjects

Per capita cigarette consumption computed from cigarette sales and from adult respondents to the large, cross‐sectional, population‐based California Tobacco Surveys of 1990 (n  =  24 296), 1996 (n  =  18 616) and 2002 (n  =  20 525) were examined for similar trends.

Main outcome measure

Changes (period 1: 1990–1996; period 2: 1996–2002) in per capita cigarette consumption from self‐reported survey data were partitioned for the entire population and for demographic subgroups into the three components mentioned above.

Results

In periods 1 and 2, most of the decline in per capita cigarette consumption for the population as a whole was from current smokers smoking less followed by a reduction in ever smokers. The decline from smokers smoking less was particularly evident among young adults (18–29 years) in period 1. While the portion of the decline due to quitting in the entire population in period 1 was negligible, in period 2 it accounted for 22% of the total per capita decline. The decline from quitting in period 2 was mostly observed among women.

Conclusions

Rather than near‐term benefits from smokers quitting, population health benefits from reduced per capita cigarette consumption will likely occur over the longer term from fewer people becoming ever smokers, and more less‐addicted smokers eventually quitting successfully.  相似文献   
45.
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47.
Estrogen content of dairy and swine wastes   总被引:3,自引:0,他引:3  
Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentrations in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17beta-estradiol (E2), estrone (E1), and 17alpha-estradiol by gas chromatography-mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to areal mass application rates of estrogen to fields. Swine farrowing waste (from farrowing sows and piglets) had the highest ratios of E2 to macronutrients. Mean ratios in swine farrowing waste were roughly twice those in swine finishing waste (from growing male and nonpregnant female animals) and more than four times higher than those in dairy waste (from lactating cows in various stages of their reproductive cycles); these differences were statistically significant (alpha = 0.05). Estrone followed a similar trend. In contrast, ratios of 17alpha-estradiol to macronutrients were highest in dairy operations. These results can be used to better predict estrogen loading rates on fields receiving swine and dairy wastes.  相似文献   
48.
Industrial and municipal processes may produce and release endocrine-disrupting compounds (EDCs) into the environment, but the exact nature of their effects is difficult to investigate. EDCs typically exert their effect by affecting gene expression aberrantly. To determine if gene expression profiles could be used to detect and distinguish estrogenic EDCs, an estrogen receptor positive human breast cancer cell line (MCF-7) was exposed to known estrogenic compounds, suspected EDCs, and extracts from three effluent samples. A set of specifically estrogen-regulated genes was identified by microarray analysis. Nine estrogen up-regulated genes (IGFBP4, HSPA8, B4GALT1, XBP1, KRT8, GTPBP4, HNRPAB, SLC2A1, and CALM1) and two estrogen down-regulated genes (ID2 and ZNF217) were consistently detectable in response to estrogen and other estrogenic compounds. Gene expression patterns in cells that were exposed to effluent sample extracts were compared to gene expression patterns in cells that were exposed to known endocrines. Using this technique, two of the effluent samples were shown to have estrogenic activity. This approach could easily be extended to screen for other types of receptor-mediated endocrine disruption. For example, cells expressing androgen or aryl hydrocarbon receptors could be used in gene expression profiling assays to detect androgenic effects or for the presence of bioactive aromatic hydrocarbons. Gene expression profiling is emerging as a sensitive and specific method to screen complex samples for endocrine disrupting activity.  相似文献   
49.
Fluorotelomer alcohol biodegradation yields poly- and perfluorinated acids   总被引:2,自引:0,他引:2  
The widespread detection of environmentally persistent perfluorinated acids (PFCAs) such as perfluorooctanoic acid (PFOA) and its longer chained homologues (C9>C15) in biota has instigated a need to identify potential sources. It has recently been suggested that fluorinated telomer alcohols (FTOHs) are probable precursor compounds that may undergo transformation reactions in the environment leading to the formation of these potentially toxic and bioaccumulative PFCAs. This study examined the aerobic biodegradation of the 8:2 telomer alcohol (8:2 FTOH, CF3(CF2)7CH2CH2OH) using a mixed microbial system. The initial measured half-life of the 8:2 FTOH was approximately 0.2 days mg(-1) of initial biomass protein. The degradation of the telomer alcohol was monitored using a gas chromatograph equipped with an electron capture detector (GC/ECD). Volatile metabolites were identified using gas chromatography/ mass spectrometry (GC/MS), and nonvolatile metabolites were identified and quantified using liquid chromatography/ tandem mass spectrometry (LC/MS/MS). Telomer acids (CF3(CF2)7CH2COOH; CF3(CF2)6CFCHCOOH) and PFOA were identified as metabolites during the degradation, the unsaturated telomer acid being the predominant metabolite measured. The overall mechanism involves the oxidation of the 8:2 FTOH to the telomer acid via the transient telomer aldehyde. The telomer acid via a beta-oxidation mechanism was furthertransformed, leading to the unsaturated acid and ultimately producing the highly stable PFOA. Telomer alcohols were demonstrated to be potential sources of PFCAs as a consequence of biotic degradation. Biological transformation may be a major degradation pathway for fluorinated telomer alcohols in aquatic systems.  相似文献   
50.
Three brands of commercial roast beef were purchased and artificially inoculated with a 5‐strain Listeria monocytogenes cocktail at 2 inoculation levels (approximately 3 and 6 Log CFU/g). Although all 3 brands contained sodium diacetate and sodium lactate, inoculated Listeria cocktail survived for 16 d in all 3 brands; significant increases in L. monocytogenes numbers were seen on inoculated Brand B roast beef on days 12 and 16. Numbers of L. monocytogenes increased to 4.14 Log CFU/g for the 3 Log CFU/g inoculation level and increased to 7.99 Log CFU/g for the 6 Log CFU/g inoculation level by day 16, with the pH values being 5.4 and 5.8 respectively. To measure the cell viability in potential biofilms formed, an Alamar blue assay was conducted. Brand B meat homogenate had the highest metabolic activities (P < 0.05). By comparing its metabolic activities to Brands A and C and the inoculated autoclaved meat homogenates, results indicated that the microflora present in Brand B may be the reason for high metabolic activities. Based on the denaturing gradient gel electrophoresis and the Shannon–Wiener diversity index analysis, the “Brand” factor significantly impacted the diversity index (P = 0.012) and Brand B had the highest microflora diversity (Shannon index 1.636 ± 0.011). Based on this study, results showed that antimicrobials cannot completely inhibit the growth of L. monocytogenes in ready‐to‐eat roast beef. Native microflora (both diversity and abundance), together with product formula, pH, antimicrobial concentrations, and storage conditions may all impact the survival and growth of L. monocytogenes.  相似文献   
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