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1.
The persistent problem of water scarcity with the ever increasing demand of water has necessitated the reuse of effluent in agriculture. The present study evaluated the reuse of treated waste water and bioaccumulation properties of two fish species from a manmade lake. Trace metals content of two fish species: Clarias gariepinus and Cyprinus carpio and levels of trace metals from waste water in the lake where the fish species were harvested were determined by Inductive Couple Plasma-Optical Emission Spectrometer (ICP-OES). The trace metal values from fish samples ranged between 0.45-4.41 microg g(-1) for Cu, 16.45-72.23 microg g(-1) for Zn, 1.92-4.71 microg g(-1) for Cr, 2.45-5.65 microg g(-1) for Ni, 10.23-44.31 microg g(-1) for Mn, 9.67-46.59 microg g(-1) for Fe and 0.12-0.56 microg g(-1) for Pb. The carp exhibited a significantly higher concentration for the trace metals for all the parts analyzed (p<0.01). The levels of trace metals concentration from Cyprinus carpio was in the order liver>gill>muscle>bone and metal accumulation was in the order Zn>Fe>Mn>Cr>Ni >Cu>Pb. The concentration of trace metals such as zinc, iron, chromium and nickel were higher than the recommended legal limits for human consumption. The result revealed that properly treated waste water could be used for the purpose of aquaculture. Clarias gariepinus bio accumulated more trace metals from the lake when compared with Cyprinus carpio.  相似文献   

2.
The proximate composition of three varieties ofPiper guineense (Odusa — Ibibio/Efik) viz. Uyat Odusa (cultivated and peppery), Eting-keni Ikot (wild forest variety) and Eting-keni mben inyang (wild, riverine variety), were determined using available standard methods. Also determined were mineral, antinutrient and ascorbate levels. The cultivated pepperic variety had the highest content of crude protein and moisture (18.9% and 97% respectively) while the wild, riverine variety had the highest content of ether extract, carbohydrate and calories (7.79%, 63.38% and 398 cals respectively). The cultivated variety had appreciable amounts of phosphorus (1.12 mg/100 g), potassium (1.2 mg/100 g), sodium (0.24 mg/100 g), zinc (0.18 mg/100 g), and copper (0.18 mg/100 g) while the forest variety contained more of calcium (12.38 mg/100 g), magnesium (1.21 mg/100 g) and iron (0.85 mg/100 g). The wild riverine variety appeared to have the least mineral content but had the highest ascorbate level of 173.4 mg/100 g. Of four antinutrients assayed, the cultivated pepperic one had the least quantities while the forest variety was highest in hydrocyanic acid (85.8 mg/100 g) and glucosinolates (0.20 mg/100 g). The wild riverine variety had the highest level of total oxalate (165.0 mg/100 g). These quantities are however far below documented toxic levels.  相似文献   

3.
The diploid wild wheats Triticum monococcum ssp. thaoudar and Triticum urartu are the direct ancestors of all domesticated wheats, but almost nothing is known about the chemical composition of their kernels. Aim of this research was to assess their content in several compositional traits and to compare it with that of domesticated wheats. To this end, fifteen diploid, tetraploid and hexaploid accessions belonging to different Triticum species were tested for 1000 kernel weight, protein, ash and starch content, β-amylase activity, carotenoid, tocol, anthocyanin and polyphenol concentration. The wild einkorns had high protein (21.7 ± 0.74 g/100 g), ash (3.0 ± 0.06 g/100 g), tocol (75.1 ± 3.95 mg/kg), carotenoid (8.0 ± 0.91 mg/kg) and anthocyanin (43.0 ± 4.66 mg/kg) content, and low β-amylase activity (20.2 ± 0.84 B3U/g). T. urartu instead coupled high protein (28.0 ± 0.07 g/100 g), ash (3.3 ± 0.03 g/100 g) and tocol (63.9 ± 2.91 g/100 g) content with low carotenoid (2.7 ± 0.02 g/100 g) and high β-amylase (57.7 ± 0.11 g/100 g) levels. These results fit well with those observed in the derived wheats, i.e. domesticated and feral einkorn on one side and emmer, durum, spelt and bread wheat on the other. Several positive nutritional traits present in the diploid wild species were not lost during the transition from wild to domesticated forms.  相似文献   

4.
Seven seed samples of J. curcas, both in raw and roasted state, sold in some villages in Quintana Roo state, Mexico for human consumption were analyzed for physical characteristics, nutrients and antinutrients. The average seed weight varied from 0.53 to 0.74 g and kernel weight as proportion of raw seed weight was from 61 to 66%. The contents of crude protein, lipid and ash of kernels from raw seeds were 27–30%, 55–62% and 3.7–5.2% respectively. The levels of antinutrients in meal from the raw seeds were: trypsin inhibitor activity (14.6–28.7 mg trypsin inhibited/g), lectin (25.6–52.2 unit; one unit is the reverse of minimum amount of mg meal/ml assay which produced haemagglutination), saponins (1.9–2.3% as diosgenin equivalent) and phytate (8.4–10%). Phorbol esters in kernels from raw seeds were not detected in four samples and in other three samples it ranged from 0.01 to 0.02 mg/g as phorbol-12-myristate 13-acetate equivalent. Roasting of seeds inactivated almost 100% of trypsin inhibitor activity. Although lectin activity reduced on roasting, it was still present in high amounts. Saponins, phytate and phorbol esters were not affected by roasting.  相似文献   

5.
Using broken rice and rice bran as raw material, texturized rice (TR) was prepared by Improved Extrusion Cooking Technology (IECT) in which gelatinization is formed by means of low temperature and high pressure. The expansion of extrudate was hardly changed so that TR showed similar texture properties and shape with polished rices. The effect of rice bran addition (0% and 4%) and IECT conditions, including feed moisture content (26.6-33.4%), screw speed (20.1-32.6 rpm) and shearing compression metering zone temperature (SCMT, 69.8-120.2 °C) on the physicochemical, texture and nutritional characteristics of TR, were investigated by response surface methodology using Central Composite Design. When the bran addition was 4%, feed moisture content was 30%, screw speed was 26.6 rpm, SCMT was 95 °C, prepared TR contained 16.61 ± 0.02% of total dietary fiber, 9.40 ± 0.04% of protein, 3.68 ± 0.03% of fat, 2.42 ± 0.02 μg/g of thiamin, 0.52 ± 0.01 μg/g of riboflavin and 16.07 ± 0.12 mg/100 g of γ-oryzanol (dry matter content). The content increase of TDF for TR was 15.81% and the content increases of nutrients for thiamin, riboflavin, and γ-oryzanol were 1.39 μg/g, 0.24 μg/g, and 8.99 mg/g dry matter content, respectively, compared with those of polished rice.  相似文献   

6.
四川黑茶品质化学成分的研究   总被引:14,自引:2,他引:12  
采用氨基酸自动分析法、高效液相色谱法分析了四川黑茶原料、渥堆叶、康砖成品茶的氨基酸、儿茶素组成含量及咖啡碱、茶多酚、水浸出物的含量。四川黑茶原料氨基酸含量为1424.00βmg/100g,必需氨基酸含量为547.00βmg/100g,茶氨酸含量为87.15βmg/100g,儿茶素含量为27.63βmg/g,咖啡碱、茶多酚、水浸出物含量分别为1.30%、8.18%、26.94%;渥堆叶氨基酸含量为1590.00βmg/100g,必需氨基酸含量为668.00βmg/100g,茶氨酸含量为67.62βmg/100g,儿茶素含量为27.52βmg/g,咖啡碱、茶多酚、水浸出物含量分别为1.24%、7.90%、24.53%;康砖成品茶氨基酸含量为1420.00βmg/100g,必需氨基酸含量为529.00βmg/100g,茶氨酸含量为66.88βmg/100g,儿茶素含量为13.65βmg/g,咖啡碱、茶多酚、水浸出物含量分别为1.27%、5.99%、23.92%。  相似文献   

7.
Freshly harvested cocoa bean was subjected to natural fermentation for 3, 6, 9 or 12 days. The proximate, mineral, hydrocyanate (HCN), oxalate and theobromine levels in the products were determined and compared with those of raw (unfermented) cocoa. The latter sample had the following composition: protein (N×6.25), 17.5; lipid, 62.9; ash, 4.4; fibre, 5.9; and nitrogen-free extract (NFE), 9.3% dry matter. The effect of fermentation was variable, depending on duration and the nutrient under consideration. At day 3, protein content (17.6) was not different, but at day 6 (19.8) was higher (p<0.01), while days 9 and 12 (14.6 and 15.2, respectively) were lower (p<0.01) in comparison with the raw value. Inorganic P steadily decreased from 201.0 (raw) to 102.0 mg/100 g dry matter (day 12) but only the days 9 and 12 values were significantly different (p<0.05), whereas Ca increased from 29.2 (raw) up to 60.4 mg/100 g dry matter (day 3). The antinutrients, HCN, oxalate, and theobromine decreased with increasing duration of fermentation. The decreases for days 6, 9 and 12 were significant (p<0.05). The results are discussed with regard to optimization of the duration of cocoa fermentation for improved nutrient profile.  相似文献   

8.
Six non-conventional leafy vegetables consumed largely by the rural populace of Nigeria were analyzed for mineral composition. Mineral contents appeared to be dependent on the type of vegetables. Amaranthus spinosus and Adansonia digitata leaves contained the highest level of iron (38.4 mg/100 g and 30.6 mg/100 g dw, respectively). These values are low compared to those for common Nigerian vegetables but higher than those for other food sources. All the vegetables contained high levels of calcium compared to common vegetables, thus they could be a rich source of this mineral. Microelement content of the leaves varied appreciably. Zinc content was highest in Moringa oleifera, Adansonia digitata and Cassia tora leaves (25.5 mg/100 g, 22.4 mg/100 g and 20.9 mg/100 g dw, respectively) while the manganese content was comparatively higher in Colocasia esculenta. The concentrations of the mineral elements in the vegetables per serving portion are presented and these values indicate that the local vegetables could be valuable and important contributors in the diets of the rural and urban people of Nigeria. The mean daily intake of P, Mg, Ca, Fe, Cu and Zn were lower than their recommended dietary allowances (RDAs). However, the manganese daily intake was found not to differ significantly ( p = 0.05) from the RDA value.  相似文献   

9.
Different spices, dry fruits and plant nuts commonly consumed in Pakistan were assayed for the heavy metals cadmium, lead, copper, zinc, iron and manganese by the potentiometric stripping analysis and AA spectrophotometry. The results revealed wide variation in heavy metal content among different biological materials. Mixed spices generally exhibited higher value for trace metals specially lead (6.6–9.2 µg/g), cadmium (0.65–1.34 µg/g), iron (142.3–285.0 µg/g) and zinc (64.2–65.8 µg/g). Dry fruits contained relatively lesser amounts of heavy metals than plant nuts. Almonds contained higher levels of lead (1.02 µg/g) and cadmium (0.24 µg/g) than other nuts and dry fruits.  相似文献   

10.
The phytic acid content of refined (hand-made and factory-made) and whole (factory-made) wheat flours, much consumed in the Canary Islands, have been determined in this study. A total of 200 samples of flours from different types (100 refined and 100 whole) were analysed. The method proposed by Garcı́a-Villanova et al. (1982) was used for determination of phytic acid content in wheat flours. Most of the phytic acid concentrations are within the range 2–4 mg/g for the refined flours and 6–10 mg/g for the whole ones. The arithmetic mean obtained from all the samples studied is 3·77 mg/g for hand-made, refined flours, 2·96 mg/g for factory-made refined flours and 8·50 mg/g for the whole ones. On analysing the phytic acid content in all the flour samples, significant differences were observed for the different types of flour. Refined flours had a content lower than whole ones.  相似文献   

11.
Chemical and functional properties of unprocessed (raw) and locally processed seeds ofBrachystegia eurycoma, Detarium microcarpum andMucuna sloanei that affect their utilization as sources of human food were investigated. The seeds, which are underutilized food sources in Nigeria, were subjected to local processing methods which included roasting, boiling, dehulling/shelling, soaking and the changes in composition and functional properties were estimated. Chemical analyses showed that the crude protein contents of the raw seeds ranged from 12.2 to 23.2%; fat varied from 4.9 to 12.0%. The level of phytic acid in the raw seeds (192.4–215 mg/100 g) was observed to be lower than the levels found in some commonly consumed pulses in Nigeria. There were no significant differences (p>0.05) between crude protein contents and the least gelation concentrations of the raw and processed samples, but processing (roasting, boiling, dehulling and soaking) significantly (p=0.011) improved in vitro protein digestibility, water and fat absorption capacity and decreased the bulk density, nitrogen solubility and the phytic acid and polyphenol contents of the samples. Processed samples had high water (3.4–3.8 g/g) and fat (1.8–2.1 g/g) absorption capacities and hence may be useful as functional agents in fabricated foods such as bakery products and ground meat formulations.  相似文献   

12.
为评价不同品种紫米淀粉、脂肪、花青素、多酚、氨基酸和矿质元素间的差异,探究不同营养成分之间的关系,选取云南墨江(MJ)、湖南新化(HN)、贵州黎平(GZ)和陕西汉中(SX)4个产地的紫米,并与红米(R)、黑米(B)进行比较。结果显示,不同产地紫米成分含量存在差异,具有不同营养特征。HN紫米的淀粉含量最低(68.13%),脂肪(2.38%)、矿质元素Fe、K、Mg、Mn、Na、P、Zn含量最高,其中Mn(80.37 mg/kg)、Na(10.75 mg/kg)元素显著高于其他产地;MJ和SX紫米花青素(533.03 mg/kg,412.54 mg/kg)、多酚(340.55 mg/100 g,387.91 mg/100 g)含量显著高于其他产地,而GZ紫米花青素(156.55 mg/kg)和多酚(239.23 mg/100 g)显著低于其他产地紫米。SX紫米氨基酸总量(74.37 g/kg)与必需氨基酸(total essential amino acids,ΣEAA,26.09 g/kg)含量最高,与其他紫米差异不显著。紫米成分间相关性分析显示,花青素与多酚呈极显著正相关(0.625),二者分别与Ca呈显著负相关(-0.571,-0.549)。Asp、Gly与Fe、Ca呈显著正相关,大部分元素间呈显著正相关。不同有色稻米间,红米淀粉(74.73%)含量最高,花青素(9.05 mg/kg)、氨基酸总量(55.94 g/kg)、ΣEAA(19.78 g/kg)、Fe(6.51 mg/kg)、Mg(609.41 mg/kg)、P(1746.72 mg/kg)元素含量最低,与紫米和黑米差异显著(P<0.05)。黑米花青素(533.03 mg/kg)、多酚(453.53 mg/100 g)含量显著高于(P<0.05)其他有色稻;黑米和紫米氨基酸含量差异不显著(P>0.05),但显著高于(P<0.05)红米。有色稻ΣEAA与非必需氨基酸总量(total non-essential amino acid,ΣNEA)比例在0.54左右。主成分分析将3种有色稻分为红米、紫黑米两组,前3个主成分可以解释总方差的91%。第一主成分(PC1)贡献率为67.5%,代表矿质元素,说明产地是有色稻米成分组成差异的主要原因。第二主成分(PC2)占总方差的18.2%,主要为总花青素含量、氨基酸等。  相似文献   

13.
通过田间微区模拟试验,以中苎1号、湘苎2号和湘苎3号为材料,研究苎麻对镉(Cd)胁迫的响应及其吸收铅(Pb)、铜(Cu)、锌(Zn)和镍(Ni)的能力。结果表明:供试3个品种均有较强的Cd耐受能力(耐受Cd的阈值为11.7mg·kg^-1),其中湘苎3号耐受Cd的能力最强,在Cd添加量为0~100mg·kg^-1时,其有效株为15.7—29.0株/m^2、生物量为0.67~1.01kg·m^-2、原麻产量为55.4—76.8g·m^-2,显著高于其它2个品种;随着土壤Cd添加量的增大,3个品种地上部的Cd含量及其累积量均显著增加,最高可迭61.5mg·kg^-1与49.6mg·m^-2,表明苎麻对cd具有较强的富集能力,但并未达到Cd的超富集植物的水平;Cd胁迫条件下,3个品种对Pb、Cu、Zn、Ni等重金属的吸收因元素种类的不同而异,中苎1号对Pb、Ni吸收呈现出随土壤Cd添加量增大而增加的趋势,湘苎3号对Zn、Ni吸收则呈现出随土壤Cd添加量增大而减少的趋势,但土壤Cd添加量对3个品种吸收Cu的影响并不明显。同时,苎麻还具有较好的经济效益且不进入食物链,是一种理想的修复与利用重金属污染土壤的备选植物,但镉胁迫对苎麻吸收Pb、Cu、Zn、Ni等重金属的影响机制尚需进一步研究。  相似文献   

14.
The furosine content of infant cereals has been used to evaluate the thermal damage caused to those foods during their manufacture (toasting, amylolysis and drying steps). The mean furosine contents of raw and toasted flours were 13·7 and 13·8 mg/100 g of protein, respectively. The furosine content increased to 47·3 mg/100 g of protein after hydrolysis usingalpha-amylase. The amylolysis process raised the reducing sugar content from 0·5% for raw samples to 12·7%. The furosine content of infant cereals rose to average levels of 500 mg/100 g of protein after roller-drying. The infant cereals with the highest levels of reducing sugars, with or without soy flour, exhibited the highest furosine contents. Furosine is a useful indicator to evaluate the progress of the Maillard reaction during the amylolysis and roller-drying stages of infant cereals manufacture.  相似文献   

15.
分析了我国不同产区不同品种亚麻籽的组成及体外抗氧化特性。结果表明,除基本组成成分外,不同品种亚麻籽主要活性组分含量和体外抗氧化活性具有显著差异。α-亚麻酸、木酚素、总酚酸、黄酮、生育酚、植物甾醇含量范围分别为33.42%~59.74%,120~918 mg/100g,209~491 mg/100g,33.04~75.63 mg/100g,8.68~20.75 mg/100g,340~596 mg/100g。亚麻籽提取物DPPH值和FRAP值分别为4 357~8 146 μmol Trolox/100g, 8 289~15058 μmol Trolox/100g。此外,不同品种亚麻籽抗营养因子生氰糖苷含量差异较为显著(5.57~11.34 mg HCN/100g)。相关性分析结果表明,亚麻籽提取物体外抗氧化活性与木酚素、总酚酸和黄酮含量具有显著相关性(p<0.05)。主成分分析和聚类分析结果表明,亚麻籽主要酚类化合物及其抗氧化活性主要依赖于亚麻籽品种特性,而非种植区域。  相似文献   

16.
Significant differences in tuber glycoalkaloid (TGA) content were found among five commercial varieties and B5141-6 grown at 39 different locations in 28 states. Line B5141-6 had the highest average TGA content, 29.3 mg/100 g in 1970 and 28.1 mg/100 g in 1971. Average TGA contents in 1970 of Kennebec, Russet Burbank, Katahdin, Irish Cobbler, and Red Pontiac were 9.7, 7.9, 7.9, 6.2, and 4.3 mg/100g, respectively. There were also significant location effects. Possible causes of high TGA levels are discussed.  相似文献   

17.
The composition and quality of edible tender stems or cladodes of 3 Prickly Pear Cactus species (Opuntia amyclaea, O. ficus-indica, and O. inermis) were studied at different stages of development. This traditional Mexican vegetable is called nopalitos in Spanish and cactus leaves in English. Cladodes harvested when 20 cm in length have the following average composition per 100 g: 91.7 g of water, 1.1 g of protein, 0.2 g of lipid, 1.3 g of ash, 1.1 g of crude fiber, 4.6 g of complex carbohydrates and 0.82 g of simple sugars, 12.7 mg of ascorbic acid and 28.9 µg of carotenes. The cladode's juice has an average pH of 4.6, 0.45% titratable acidity and 6.9% soluble solids. The components which varied most during development of the cladodes were: carotenes, acidity and total carbohydrates which increased, and protein and crude fiber (acid-detergent) which decreased. The nutritive value of the tender cladodes in the stages of growth at which they are commonly harvested and consumed (15 to 25 cm long weighing 50 to 80 g per stem), was similar for the 3 species.  相似文献   

18.
本研究采用高效液相色谱、酶标检测技术,确定可可豆加工过程中黄烷醇类物质组成变化趋势,分析抗氧化活性。在发酵及焙炒阶段检测黄烷醇物质儿茶素(C)、表儿茶素(EC)、表没食子儿茶素(EGC)、表儿茶素没食子酸酯(ECG)、原花青素B1(PC B1)、原花青素B2(PC B2)。结果表明:经7 d发酵各成分含量分别为EGC(8.521~ 3.017 mg/g)、C(15.521~6.633 mg/g)、EC(19.615~3.142 mg/g)、ECG(0.236~0.084 mg/g)、PC B1(19.152~10.774 mg/g)、PC B2(4.254~2.083 mg/g),发酵使得可可豆中儿茶素及低聚物含量大量减少;135 ℃不同时间焙炒下,各物质含量分别为EGC(3.079~2.221 mg/g)、C(8.611~5.143 mg/g)、EC(3.956~0.982 mg/g)、ECG(0.111~0.070 mg/g)、PC B1(10.987~ 8.223 mg/g)、PC B2(2.385~1.534 mg/g)。可可豆在高温焙炒时,DPPH、ABTS自由基清除率呈下降趋势,降低了可可抗氧化活性。研究结果为可可加工提供相关保健功能性的依据。  相似文献   

19.
绿咖啡油是一种富含生物活性成分的功能性油脂,贮藏过程中极易氧化酸败影响产品品质。本文以海南地区兴隆咖啡为原料提取绿咖啡油,系统研究在60 ℃加速贮藏36 d内氧化指标、生物活性成分及表征氧化的光谱特征峰变化。结果表明:过氧化值、茴香胺值、硫代巴比妥酸、总氧化值初始值分别为0.97±0.04 meq/kg、4.19±0.14、55.08± 1.98 nmol/mL、8.05±0.06,经过36 d的氧化分别显著升高到28.56±0.15 meq/kg、19.19±0.13、102.38±2.18 nmol/mL、133.43± 0.45。本研究中共鉴定出11种脂肪酸,在绿咖啡油氧化过程中,饱和脂肪酸与不饱和脂肪酸比值由1.14上升至1.49。利用高效液相色谱测定绿咖啡油中的二萜类物质和生育酚,咖啡豆醇、咖啡醇的初始含量分别为21.01±0.31 mg/g、23.44±0.52 mg/g,在氧化24 d后升高至8.21±0.10 mg/g、8.99±0.02 mg/g,随后含量趋于稳定。共定性出α、δ和γ-生育酚,总生育酚含量由初始的49.75±0.88 mg/100 g在氧化18 d达到最大值53.70±1.72 mg/100 g,在氧化结束时降至34.58± 0.05 mg/100 g。利用傅里叶变换红外光谱(FTIR)从特征官能团的角度分析绿咖啡油的氧化过程,油脂在3008、2927、2854、1745、1461、1375、1238、1164、721 cm-1处有特征吸收峰。采用拉曼光谱技术表征绿咖啡油加速贮藏中的氧化变质,在1000~1800 cm-1波段的峰强度有明显减弱趋势。本研究表明绿咖啡油在热诱导下的贮藏过程中发生了明显的氧化反应,可为提升绿咖啡油贮藏稳定性提供理论参考。  相似文献   

20.
Nutritional (ascorbic acid, dehydroascorbic acid and carotenes); antinutritional and toxic components (oxalic acid, nitrate and erucic acid) were determined in sixteen popular species of wild edible plants which are collected for human consumption in southeast Spain. Ascorbic+dehydroascorbic acids contents were very high in several species, especially in Chenopodium album L. (155 mg/100 g). Carotenoid content ranged from 4.2 mg/100 g (Stellaria media Villars) to 15.4 mg/100 g (Amaranthus viridis L.). A range of values was found for oxalic acid from absence to 1100 mg/100 g of plant material. Nitrate contents ranged from 47 mg/100 g ( Salicornia europaea L.) to 597 mg/100 g (Amaranthus viridis L.). Low amounts of erucic acid were found in the Cruciferae family (Sisymbrium irio L. 1.73%; Cardaria draba L. 1.23%) and Plantago major L. 3.45%.  相似文献   

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