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161.
对油松花粉形成、发育以及萌发过程中淀粉粒的动态分布作了详细观察 ,结果表明 :小孢子母细胞进入减数分裂前开始在细胞质周围积累淀粉 ,其量达到高峰时开始减数分裂 ,中期I之后淀粉粒逐渐呈赤道聚积 ,末期II,淀粉粒分配于四个子细胞周围。四细胞花粉形成后 ,管细胞迅速积累大量淀粉 ,该淀粉转移到气囊后 ,散粉开始。花粉即将萌发对 ,体内又出现大量淀粉 ,并在花粉管伸长过程中流入管中  相似文献   
162.
任彩霞 《保鲜与加工》2022,22(5):101-106
综述了小米的营养组成、营养特点和加工特性,以及目前在婴幼儿食品中的研究进展、应用状况、存在的问题,并对其发展前景进行了展望,以期为小米在婴幼儿食品中的开发应用提供科学参考。  相似文献   
163.
Whole grain phytochemicals and health   总被引:13,自引:0,他引:13  
Phytochemicals and antioxidants in whole grains have not received as much attention as the phytochemicals in fruits and vegetables although the increased consumption of whole grains and whole grain products has been associated with reduced risk of developing chronic diseases such as cardiovascular disease, type 2 diabetes, some cancers and all-cause mortality. Recent research has shown that the total phytochemical content and antioxidant activity of whole grains have been commonly underestimated in the literature, and that whole grains contain more phytochemicals than was previously reported. Most whole grain phenolics are in bound form, 85% in corn, 76% in wheat, and 75% in oats. In addition, whole grains contain unique phytochemicals that complement those in fruits and vegetables when consumed together. The beneficial effects associated with whole grain consumption are in part due to the existence of the unique phytochemicals of whole grains. The majority of phytochemicals of whole grains that are beneficial for health are present in the bran/germ fraction. In whole wheat flour, the bran/germ fraction contributed 83% of total phenolic content, 79% of total flavonoid content, 78% of total zeaxanthin, 51% of total lutein, and 42% of total β-cryptoxanthin. The bran/germ fraction of whole wheat may therefore impart greater health benefits when consumed as part of a diet, and help reduce the risk of chronic diseases. This paper will review recent research on the phytochemicals and antioxidant activity of whole grains and their unique contribution to the health benefits of whole grains.  相似文献   
164.
Background: This study was conducted to evaluate the apparent metabolizable energy (AME) and true metabolizable energy (TME) contents in 30 sources of corn distillers dried grains with solubles (DDGS) in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score. Methods: Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy (ME) contents, measured for color score and chemical composition (crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber), to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed (50 g) to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses. Results: Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content (-0.64, P 〈 0.0]) and between ME and yellowness score (0.39, P 〈 0.05) of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 + 0.5]475 GE - 0.10003 NDF + 0.1 3380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R^2 = 0.70). The best-fit regression equation for TME content of DDGS was TME = 7.92283 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R2 = 0.70). Conclusions: This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.  相似文献   
165.
Transgenic photo-thermo sensitive genic male sterility Oryza sativa L. cv. “261S” plants with the anti-Waxy gene were successfully obtained using an Agrobacterium tumefaciens-mediated co-transformation method. Marker-free homozygous transgenic lines with the anti-Waxy gene were obtained. The setting seed rates of the transgenic plants via self-pollination or via crossing with the restorer line WX99075 rice and the 1000-grain weight of the transgenic plants and the F2 hybrid seeds obtained by crossing the transgenic or non-transgenic plants with the restorer line WX99075 rice, and the number of panicles of the transgenic plants and yields of the F2 hybrid rice, were analysed. Quality indexes of the transgenic plants and of the F2 hybrid seeds were analysed. Our researches results indicate that hybrid female and hybrid descendant edibility could be improved via the introduction of the anti-Waxy gene, but the grain yields of the reserve seeds via self-pollination of the transgenic photo-thermo sensitive genic sterile lines and of the hybrid rice were not affected.  相似文献   
166.

Background

This study was conducted to evaluate the apparent metabolizable energy (AME) and true metabolizable energy (TME) contents in 30 sources of corn distillers dried grains with solubles (DDGS) in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score.

Methods

Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy (ME) contents, measured for color score and chemical composition (crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber), to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed (50 g) to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses.

Results

Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content (-0.64, P < 0.01) and between ME and yellowness score (0.39, P < 0.05) of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R2 = 0.70). The best-fit regression equation for TME content of DDGS was TME = 7.92283 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R2 = 0.70).

Conclusions

This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.  相似文献   
167.
Transformations of nitrogen (N) from poultry litter (PL), dairy manure compost (DMC), anaerobically digested fiber (ADF), Perfect Blend 7–2–2 (PB), a compost/litter mixture (C/L), dried distillers grains from ethanol production (DG), and mustard meal from biodiesel production (MM) applied to a Quincy fine sand were investigated in an incubation experiment over 210 days. The cumulative release totals of available N after 210 days were 61, 61, 56, 44, 29, 2, and –2% for the total N in MM, PB, DG, PL, C/L, DMC, and ADF, respectively. With application of MM and DG, ammonium (NH4-N) accumulated initially in the soil with very little nitrification, possibly because of inhibition of nitrification related to chemical compounds in the amendments. Mineralization of organic N to NH4-N and nitrate (NO3-N) was relatively slow from MM- and DG-amended soils, indicating the potential for using biofuel by-products as slow-release N sources for plants.  相似文献   
168.
青稞在西藏长期以来的产业发展中,基本以糌粑、青稞米等初级产品为主,为开拓更多的青稞加工方式,丰富产品类别,对青稞粉进行挤压膨化及工艺的优化,并结合当地杂粮鸡爪谷等,通过挤压膨化提升青稞的口感及相关产品的营养价值。青稞杂粮粉挤压膨化后,对不同膨化参数组合的青稞杂粮粉的吸水性、水溶性、堆积密度、沉降性、分散性、润湿性等指标进行了测定,发现膨化参数组合之间没有表现出明显的速溶差异特性。青稞杂粮膨化率的大小不跟速溶性指标呈正比关系。根据膨化效果最佳膨化工艺参数为物料水分含量为12%,Ⅲ区温度170℃,主轴转速20 Hz,喂料速度8 Hz;从速溶粉的生产工艺来看,最佳工艺为物料水分含量为16%,Ⅲ区温度170℃,主轴转速23 Hz,喂料速度8 Hz。  相似文献   
169.
分蘖和乳熟期控制灌溉对水稻生长和产量的影响   总被引:2,自引:1,他引:1  
为了合理的制定水稻控灌灌溉制度,开展了单生育期内水分控制灌溉对水稻生长影响的试验研究。在水稻分蘖(FN)和乳熟期(RS)分别以土壤饱和含水量的80%(FN1,RS1)和90%(FN2,RS2)作为灌溉下限进行控制灌溉。结果表明:与常规浅湿灌溉相比,生育期水分控制灌溉可以减少该生育期内灌水次数和灌水量,控制灌溉停止后,分蘖期处理水稻需水出现补偿效应,乳熟期则不明显;控制灌溉不利于水稻株高生长,有利于增加每穗粒数和每穗实粒数,对千粒重影响不明显;控制灌溉节水效应显著,但同时减产作用也十分明显,FN1、FN2、RS1和RS2处理分别节水21.1%,16.2%,29.4%和18.1%,减产27.8%,26.8%,29.5%和19.2%;分蘖期控制灌溉减产作用大于节水作用,灌溉水利用效率(IWUE)显著下降,较对照处理降低8.5%~12.7%,乳熟期控制灌溉IWUE和对照差异不显著。因此,从生产角度来讲,当灌溉水水资源匮乏需要控制灌溉时,为了提高IWUE,宜在乳熟期适当控灌,而分蘖期不宜控制灌溉。  相似文献   
170.
烤烟叶片稳定碳同位素组成的品种分异与超微结构的关系   总被引:1,自引:1,他引:0  
以云南烟区主栽烤烟品种‘红大’、‘K326’、‘云烟87’和‘NC71’成熟中期中部烟叶作为试验材料,对其稳定碳同位素组成(δ13C)与叶肉细胞叶绿体、腺毛和气孔超微结构关系进行研究,结果表明:(1)δ13C值‘K326’>‘NC71’>‘红大’>‘云烟87’。(2)叶绿体中嗜锇颗粒平均数为‘K326’>‘NC71’>‘红大’>‘云烟87’。(3)‘K326’具分泌功能的长柄腺毛最多且最饱满,‘红大’则较差。(4)气孔总密度为‘K326’>‘NC71’>‘云烟87’>‘红大’。(5)烟叶δ13C值与嗜锇颗粒平均数呈显著正相关(P<0.05),与淀粉粒平均数、叶绿体长度呈弱正相关(P>0.05),与淀粉粒长度呈及腺毛总密度呈弱负相关(P>0.05),与气孔总密度呈正相关关系(P>0.05)。以上结果反映出烟叶δ13C值存在品种差异,并且这种差异与叶片超微结构存在一定相关性。  相似文献   
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