VBM 得到 NIH 的资助 [K08EY020530, R01EY024665, R01EY025225, R01EY024698 和 R21AG050437], 桃乐丝杜克慈善基金会补助金: 2013103, 并研究, 以防止失明 (填料), 纽约, 纽约州。MT 和 T32GM007337 得到 NIH 的资助。

这项研究是由爱荷华大学和 #39 的机构审查委员会批准的, 并遵循《赫尔辛基宣言》中所规定的原则. 
 1. 中心和黄斑活检穿孔 <ol> <li> 打开和蝶形人眼, 如前一出版物所述, 它由4独立的组织瓣组成. 5 </li> <li> 开始时, butterflied 人眼放置在培养皿中, 将一个 4 mm 的穿孔活检工具放在凹窝上, 向下按压, 然后轻轻滚动, 直到在凹腹周围进行切口. </li>
	<li> 接下来, 在黄斑的拱廊内, 通过居中并按下一个 8 mm 的皮肤穿孔活检工具, 在黑点周围产生切口, 施加柔和的压力和滚动。这将产生第二个外环的组织周围的第一. </li>
</ol> 2。外周视网膜活检穿孔 <ol> <li> 使用 4 mm 的皮肤穿孔活检工具在外围视网膜上进行一系列击打, 就在拱廊外。在这里, 为每个象限襟翼做两拳. 
	注: 在所有的拳打后, 眼睛将有两个同心拳在中心, 代表中央凹和黄斑, 两个拳在底部的每瓣-总计8拳在周边视网膜. </li>
</ol> 3。凹和黄斑活检收集 <ol> <li> 当组织现在准备好收集, 收集所有组织活检在分开的离心管和冷冻使用液氮为下游处理。将所有样品存储在-80 和 #176; C 直到使用. </li>
	<li> 使用弯曲的 0.12 Colibri 钳抓住视网膜凹的半透明组织的边缘。从底层视网膜色素上皮中收集、提升和分离中心组织. </li>
	<li> 同样, 使用 0.12 Colibri 钳来抓住半透明的黄斑组织的外环。如果组织仍然连接到基础或相邻组织, 使用一副保罗·韦斯科特剪刀仔细修剪边缘, 捕获只是视网膜成分和解剖的任何视神经组织包括在冲床. </li>
</ol> 4。周边视网膜采集 <ol> <li> 使用弯曲的 0.12 Colibri 钳将周围的视网膜组织瓣轻轻分开, 从底层的 RPE-脉络膜, 并在单个离心管中放置. </li>
	<li> 在残留的玻璃体凝胶的情况下, 使用镊子解除和分离的凝胶尽可能多之前收集的视网膜组织。一旦视网膜被移除, 色素 RPE-脉络膜仍在下方. </li>
</ol> 5。中心和黄斑视网膜色素上皮集合 <ol> <li> 使用 0.12 Colibri 钳来抓住暗 RPE-脉络膜组织的边缘, 位于所移除凹区的下方。仔细分离这个组织从巩膜和收集. </li>
	<li> 使用同样的钳子, 抓住边缘的黑暗 RPE-脉络膜组织的基础上清除黄斑区。仔细地把这个组织从巩膜上分离出来, 抓住环周围不同点的边缘, 轻轻地拉。最终, RPE-脉络膜组织的环会脱落, 并可能被收集. 
	注意: 相反手上的二次钳在去除视网膜色素上皮组织的过程中可以起到帮助作用。像视网膜组织, Wescott 剪刀可以用来帮助删除任何组织, 没有完全切割使用冲床工具. </li>
</ol> 6。外周视网膜 rpe-脉络膜集合 <ol> <li> 使用 0.12 Colibri 钳将 RPE-脉络膜剥离到8外围冲头区域. </li>
	<li> 如前所述, 将 RPE-脉络膜组织置于离心管中, 并使用液氮进行下游加工。将所有样品保持在-80 和 #176; C 直到使用. </li>
</ol> 7。剪刀解剖 注意: 如果穿孔活检刀片是钝的或穿孔活检工具不够用力, 可能不会有一个 clean-cut 周围的组织. 
<ol> <li> 在这些情况下, 尽可能地将组织拉离, 然后使用保罗·韦斯科特剪刀修剪和分离. </li> </ol>

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未声明任何利益冲突。

组织收集后, 样品处理和处理是至关重要的考虑因素14。液氮的保存优于化学固定, 因为后者可能导致蛋白质结构的破坏, 这可能会扭曲下游分析。此外, 液氮保存是首选的方法, 不涉及冻结样品。值得注意的是, 与0° c15相比, Ferrer et al.在4° c 或室温下保存的脑样品的蛋白质水平有显著差异。此外, 重要的是要小心, 当处理样品, 由于特定的化学和物理治疗前?...

视网膜、RPE 和脉络膜是复杂的组织, 在蛋白质表达、生理功能和病理敏感性方面表现出重要的区域差异1,2。例如, 与年龄相关的黄斑变性 (AMD)、视网膜色素变性和中央浆液性视网膜病变等疾病都表现出在凹、黄斑或视网膜周围的特征定位1,3, 4,6。在这里, 我们提出了一个方法来演示如何独立取样的视网膜区域。该方法的总体目标是提供一个可靠的指南, 收集的组织样本从中心, 黄斑, 周边地区的人视网膜和 RPE-脉络膜的蛋白质组分析。这一技术的发展和应用的基本原理是, 通过对这些特定的视网膜区域的蛋白质组分析, 可以获得重要的分子洞察力, 这些区域的生理和病理功能。
这种方法有望揭示相关区域疾病敏感性的蛋白质组基础, 并有助于确定新的具体治疗目标。事实上, 蛋白质组学对玻璃体及其与视网膜相互作用的研究为健康和患病组织的分子组成和功能提供了重要的洞察力5,7,8,9,10,11,12,13. 然而, 对不同的视网膜区域缺乏明确的比较蛋白质组分析。该技术将有助于支持这些急需的研究, 提供比其他方法的优势, 通过展示一个可靠的和可再生的组织收集方法。更重要的是, 该方法是非常容易获得的, 利用标准和现成的组织穿孔活检工具。我们的技术强调适当的收集和储存组织的蛋白质组处理, 使重要的考虑蛋白的稳定性和降解。因此, 这种方法是最适合的研究者考虑下游分子分析蛋白质的因素。

<table border="0" cellpadding="0" cellspacing="0" width="691">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">4-mm skin punch biopsy tool</td>
			<td style="width:189px;">Miltex</td>
			<td style="width:119px;">REF 33-34</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">8-mm skin punch biopsy tool</td>
			<td style="width:189px;">Miltex</td>
			<td style="width:119px;">REF 33-37</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">0.12 Colibri Forceps</td>
			<td style="width:189px;">Stephens Instruments</td>
			<td style="width:119px;">S5-1145</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Wescott Scissors</td>
			<td style="width:189px;">Sklar Surgical Instruments</td>
			<td style="width:119px;">64-3146</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Microfuge tubes</td>
			<td style="width:189px;">Eppendorf</td>
			<td style="width:119px;">#022364111</td>
			<td>1.5 mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Liquid Nitrogen</td>
			<td style="width:189px;">Praxair, Inc.</td>
			<td style="width:119px;">7727-37-9 [R]</td>
			<td></td>
		</tr>
	</tbody>
</table>

dissection of human retina and rpe-choroid for proteomic analysis

人视网膜由感觉 neuroretina 和底层的视网膜色素上皮 (RPE) 组成, 它与血管脉络膜层紧密地复合。视网膜的不同区域是解剖学上和分子上的区别, 促进独特的功能和证明差异易感性的疾病。蛋白质组分析的每个区域和层可以提供重要的洞察力的分子过程中的许多疾病, 包括年龄相关的黄斑变性 (AMD), 糖尿病和青光眼。然而, 在进行定量蛋白质组分析之前, 视网膜区域和层的分离是必不可少的。在这里, 我们描述了解剖和收集的中心, 黄斑, 和周边视网膜区域和底层 RPE-脉络膜复合体的方法, 涉及区域穿孔活检和手工清除组织层从人眼。一维 SDS 页以及下游蛋白质组学分析, 如液相色谱-串联质谱 (LC-ms), 可用于识别每个解剖视网膜层的蛋白质, 揭示视网膜疾病的分子标志物。

视网膜和 RPE-脉络膜组织可以以各种方式进行处理, 以适应个人的调查。收集后, 研究员将拥有视网膜和 RPE-脉络膜组织从中心地区, 外黄斑和周边视网膜 (图 1) 的样本。具体来说, 中心区域冲床将包括凹, parafovea, 和少量的相邻 perifovea。黄斑冲头包括 perifoveal 区的其余部分以及邻近近周边区域的少量。最后, 对 mid-peripheral 和远外围区域进行了外围冲压?...

Watch this Scientific Journal Video about Dissection of Human Retina and RPE-Choroid for Proteomic Analysis at JoVE.com

Dissection of Human Retina and RPE-Choroid for Proteomic Analysis

人类视网膜由功能和分子的不同区域组成, 包括黄斑、黄斑和外周视网膜。在这里, 我们描述了一个方法使用穿孔活检和手工清除组织层从人眼解剖和收集这些不同的视网膜区域的蛋白质组分析。

人视网膜解剖与 RPE-脉络膜的蛋白质组分析

The human retina is composed of the sensory neuroretina and the underlying retinal pigmented epithelium (RPE), which is firmly complexed to the vascular ...

dissection-of-human-retina-and-rpe-choroid-for-proteomic-analysis

Research

JoVE Journal

Biochemistry

10.8K 次观看.  Columbia University. 人类视网膜由功能和分子的不同区域组成, 包括黄斑、黄斑和外周视网膜。在这里, 我们描述了一个方法使用穿孔活检和手工清除组织层从人眼解剖和收集这些不同的视网膜区域的蛋白质组分析。

视频: Dissection of Human Retina and RPE-Choroid for Proteomic Analysis

Resolving Affinity Purified Protein Complexes by Blue Native PAGE and Protein Correlation Profiling

Most proteins act in association with others; hence, it is crucial to characterize these functional units in order to fully understand biological processes. Affinity purification coupled to mass spectrometry (AP-MS) has become the method of choice for identifying protein-protein interactions. However, conventional AP-MS studies provide information on protein interactions, but the organizational information is lost. To address this issue, we developed a strategy to unravel the distinct functional assemblies a protein might be involved in, by resolving affinity-purified protein complexes prior to their characterization by mass spectrometry. Protein complexes isolated through affinity purification of a bait protein using an epitope tag and competitive elution are separated through blue native electrophoresis. Comparison of protein migration profiles through correlation profiling using quantitative mass spectrometry allows assignment of interacting proteins to distinct molecular entities. This method is able to resolve protein complexes of close molecular weights that might not be resolved by traditional chromatographic techniques such as gel filtration. With little more work than conventional AP-geLC-MS/MS, we demonstrate this strategy may in many cases be adequate for obtaining protein complex topological information concomitantly to identifying protein interactions.

Here we present protocols for affinity purification of protein complexes and their separation by blue native PAGE, followed by protein correlation profiling using label free quantitative mass spectrometry. This method is useful to resolve interactomes into distinct protein complexes.

解决由蓝变性PAGE和蛋白质相关剖析亲和纯化的蛋白复合物

Most proteins act in association with others; hence, it is crucial to characterize these functional units in order to fully understand biological ...

科研

生物化学

Fractionation for Resolution of Soluble and Insoluble Huntingtin Species

The accumulation of misfolded proteins is central to pathology in Huntington's disease (HD) and many other neurodegenerative disorders. Specifically, a key pathological feature of HD is the aberrant accumulation of mutant HTT (mHTT) protein into high molecular weight complexes and intracellular inclusion bodies composed of fragments and other proteins. Conventional methods to measure and understand the contributions of various forms of mHTT-containing aggregates include fluorescence microscopy, western blot analysis, and filter trap assays. 
However, most of these methods are conformation specific, and therefore may not resolve the full state of mHTT protein flux due to the complex nature of aggregate solubility and resolution.
For the identification of aggregated mHTT and various modified forms and complexes, separation and solubilization of the cellular aggregates and fragments is mandatory. Here we describe a method to isolate and visualize soluble mHTT, monomers, oligomers, fragments, and an insoluble high molecular weight (HMW) accumulated mHTT species. HMW mHTT tracks with disease progression, corresponds with mouse behavior readouts, and has been beneficially modulated by certain therapeutic interventions1. This approach can be used with mouse brain, peripheral tissues, and cell culture but may be adapted to other model systems or disease contexts.

A method is described for fractionation of insoluble and soluble mutant huntingtin species from mouse brain and cell culture. The method described is useful for characterization and quantification of huntingtin protein flux and aids in analyzing protein homeostasis in disease pathogenesis and in the presence of perturbations

可溶性和不溶性杭丁顿蛋白的分离分解

The accumulation of misfolded proteins is central to pathology in Huntington's disease (HD) and many other neurodegenerative disorders. Specifically, a ...

Split-BioID &#8212; Proteomic Analysis of Context-specific Protein Complexes in Their Native Cellular Environment

To complement existing affinity purification (AP) approaches for the identification of protein-protein interactions (PPI), enzymes have been introduced that allow the proximity-dependent labeling of proteins in living cells. One such enzyme, BirA* (used in the BioID approach), mediates the biotinylation of proteins within a range of approximately 10 nm. Hence, when fused to a protein of interest and expressed in cells, it allows the labeling of proximal proteins in their native environment. As opposed to AP that relies on the purification of assembled protein complexes, BioID detects proteins that have been marked within cells no matter whether they are still interacting with the protein of interest when they are isolated. Since it biotinylates proximal proteins, one can moreover capitalize on the exceptional affinity of streptavidin for biotin to very efficiently isolate them. While BioID performs better than AP for identifying transient or weak interactions, both AP- and BioID-mass spectrometry approaches provide an overview of all possible interactions a given protein may have. However, they do not provide information on the context of each identified PPI. Indeed, most proteins are typically part of several complexes, corresponding to distinct maturation steps or different functional units. To address this common limitation of both methods, we have engineered a protein-fragments complementation assay based on the BirA* enzyme. In this assay, two inactive fragments of BirA* can reassemble into an active enzyme when brought in close proximity by two interacting proteins to which they are fused. The resulting split-BioID assay thus allows the labeling of proteins that assemble around a pair of interacting proteins. Provided these two only interact in a given context, split-BioID then allows the analysis of specific context-dependent functional units in their native cellular environment. Here, we provide a step-by-step protocol to test and apply split-BioID to a pair of interacting proteins.

We provide a step-by-step protocol for split-BioID, a protein fragments-complementation assay based on the proximity-labeling technique BioID. Activated on the interaction of two given proteins, it allows the proteomics analysis of context-dependent protein complexes in their native cellular environment. The method is simple, cost-effective and only requires standard laboratory equipment.

BioID 细胞环境中特异蛋白复合物的分离-蛋白质组学分析

To complement existing affinity purification (AP) approaches for the identification of protein-protein interactions (PPI), enzymes have been introduced ...

Purification and Reconstitution of TRPV1 for Spectroscopic Analysis

Polymodal ion channels transduce multiple stimuli of different natures into allosteric changes; these dynamic conformations are challenging to determine and remain largely unknown. With recent advances in single-particle cryo-electron microscopy (cryo-EM) shedding light on the structural features of agonist binding sites and the activation mechanism of several ion channels, the stage is set for an in-depth dynamic analysis of their gating mechanisms using spectroscopic approaches. Spectroscopic techniques such as electron paramagnetic resonance (EPR) and double electron-electron resonance (DEER) have been mainly restricted to the study of prokaryotic ion channels that can be purified in large quantities. The requirement for large amounts of functional and stable membrane proteins has hampered the study of mammalian ion channels using these approaches. EPR and DEER offer many advantages, including determination of the structure and dynamic changes of mobile protein regions, albeit at low resolution, that might be difficult to obtain by X-ray crystallography or cryo-EM, and monitoring reversible gating transition (i.e., closed, open, sensitized, and desensitized). Here, we provide protocols for obtaining milligrams of functional detergent-solubilized transient receptor potential cation channel subfamily V member 1 (TRPV1) that can be labeled for EPR and DEER spectroscopy.

This article describes specific methods to obtain biochemical quantities of detergent-solubilized TRPV1 for spectroscopic analysis. The combined protocols provide biochemical and biophysical tools that can be adapted to facilitate structural and functional studies for mammalian ion channels in a membrane-controlled environment.

光谱分析 TRPV1 的纯化与重构

Polymodal ion channels transduce multiple stimuli of different natures into allosteric changes; these dynamic conformations are challenging to determine ...

Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis

Stable carbon and oxygen isotope analysis of human and animal tooth enamel carbonate has been applied in paleodietary, paleoecological, and paleoenvironmental research from recent historical periods back to over 10 million years ago. Bulk approaches provide a representative sample for the period of enamel mineralization, while sequential samples within a tooth can track dietary and environmental changes during this period. While these methodologies have been widely applied and described in archaeology, ecology, and paleontology, there have been no explicit guidelines to aid in the selection of necessary lab equipment and to thoroughly describe detailed laboratory sampling and protocols. In this article, we document textually and visually, the entire process from sampling through pretreatment and diagenetic screening to make the methodology more widely available to researchers considering its application in a variety of laboratory settings.

Stable carbon and oxygen isotope analysis of human and animal tooth enamel carbonate has been used as a proxy for individual diet and environmental reconstruction. Here, we provide a detailed description and visual documentation of bulk and sequential tooth enamel sampling as well as pretreatment of archaeological and paleontological samples.

用于稳定碳氧同位素分析的牙釉质碳酸盐的取样与预处理

Stable carbon and oxygen isotope analysis of human and animal tooth enamel carbonate has been applied in paleodietary, paleoecological, and ...

Dynamic Proteomic and miRNA Analysis of Polysomes from Isolated Mouse Heart After Langendorff Perfusion

Studies in dynamic changes in protein translation require specialized methods. Here we examined changes in newly-synthesized proteins in response to ischemia and reperfusion using the isolated perfused mouse heart coupled with polysome profiling. To further understand the dynamic changes in protein translation, we characterized the mRNAs that were loaded with cytosolic ribosomes (polyribosomes or polysomes) and also recovered mitochondrial polysomes and compared mRNA and protein distribution in the high-efficiency fractions (numerous ribosomes attached to mRNA), low-efficiency (fewer ribosomes attached) which also included mitochondrial polysomes, and the non-translating fractions. miRNAs can also associate with mRNAs that are being translated, thereby reducing the efficiency of translation, we examined the distribution of miRNAs across the fractions. The distribution of mRNAs, miRNAs, and proteins was examined under basal perfused conditions, at the end of 30 min of global no-flow ischemia, and after 30 min of reperfusion. Here we present the methods used to accomplish this analysis&#8212;in particular, the approach to optimization of protein extraction from the sucrose gradient, as this has not been described before&#8212;and provide some representative results.

Here we present a protocol to perform polysome profiling on the isolated perfused mouse heart. We describe methods for heart perfusion, polysome profiling, and analysis of the polysome fractions with respect to mRNAs, miRNAs, and the polysome proteome.

Langendorff 灌注后离体小鼠心脏 Polysomes 的动态蛋白质组学及 miRNA 分析

Studies in dynamic changes in protein translation require specialized methods. Here we examined changes in newly-synthesized proteins in response to ...

Calibration-free In Vitro Quantification of Protein Homo-oligomerization Using Commercial Instrumentation and Free, Open Source Brightness Analysis Software

Number and brightness is a calibration-free fluorescence fluctuation spectroscopy (FFS) technique for detecting protein homo-oligomerization. It can be employed using a conventional confocal microscope equipped with digital detectors. A protocol for the use of the technique in vitro is shown by means of a use case where number and brightness can be seen to accurately quantify the oligomeric state of mVenus-labelled FKBP12F36V before and after the addition of the dimerizing drug AP20187. The importance of using the correct microscope acquisition parameters and the correct data preprocessing and analysis methods are discussed. In particular, the importance of the choice of photobleaching correction is stressed. This inexpensive method can be employed to study protein-protein interactions in many biological contexts.

Calibration-free In Vitro Quantification of Protein Homo-oligomerization Using Commercial Instrumentation and Free, Open Source Brightness Analysis Software

This protocol describes a calibration-free approach for quantifying protein homo-oligomerization in vitro based on fluorescence fluctuation spectroscopy using commercial light scanning microscopy. The correct acquisition settings and analysis methods are shown.

利用商用仪器和自由开源亮度分析软件对蛋白质的聚齐聚进行无标定的体外定量化

Number and brightness is a calibration-free fluorescence fluctuation spectroscopy (FFS) technique for detecting protein homo-oligomerization. It can be ...

Proteomic Analysis of Human Macrophage Polarization Under a Low Oxygen Environment

Macrophages are innate immune cells involved in a number of physiological functions ranging from responses to infectious pathogens to tissue homeostasis. The various functions of these cells are related to their activation states, which is also called polarization. The precise molecular description of these various polarizations is a priority in the field of macrophage biology. It is currently acknowledged that a multidimensional approach is necessary to describe how polarization is controlled by environmental signals. In this report, we describe a protocol designed to obtain the proteomic signature of various polarizations in human macrophages. This protocol is based on a label-free quantification of macrophage protein expression obtained from in-gel fractionated and Lys C/trypsin-digested cellular lysis content. We also provide a protocol based on in-solution digestion and isoelectric focusing fractionation to use as an alternative. Because oxygen concentration is a relevant environmental parameter in tissues, we use this protocol to explore how atmospheric composition or a low oxygen environment affects the classification of macrophage polarization.

We present a protocol to obtain proteomic signatures of human macrophages and apply this to determination of the impact of a low oxygen environment on macrophage polarization.

低氧环境下人巨噬细胞极化的蛋白质组学分析

Macrophages are innate immune cells involved in a number of physiological functions ranging from responses to infectious pathogens to tissue homeostasis. ...

Analysis of Fucosylated Human Milk Trisaccharides in Biotechnological Context Using Genetically Encoded Biosensors

Human milk oligosaccharides (HMOs) are complex carbohydrate components of human breast milk that exhibit plentiful benefits on infant health. However, optimization of their biotechnological synthesis is limited by the relatively low throughput of detection and quantification of monosaccharide and linkages. Conventional techniques of glycan analysis include chromatographic/mass-spectrometric methods with throughput on the order of hundreds of samples per day without automation. We demonstrate here, a genetically encoded bacterial biosensor for the high-throughput, linkage-specific detection and quantification of the fucosylated HMO structures, 2&#8217;-fucosyllactose and 3-fucosyllactose, which we achieved via heterologous expression of fucosidases. As the presence of lactose in milk or in biotechnological processes could lead to false positives, we also demonstrate the reduction of signal from lactose using different strategies. Due to the high throughput of this technique, many reaction conditions or bioreactor parameters could be assayed in parallel in a matter of hours, allowing for the optimization of HMO manufacturing.

We describe here the high-throughput detection and quantification of fucosylated human milk oligosaccharides (HMOs) using a whole-cell biosensor. We also demonstrate here, the adaptation of this platform towards analysis of HMO production strains, focusing on improving the signal to noise ratio.

生物技术环境下的氟黏膜化人乳三糖--用基因编码生物传感器分析

Human milk oligosaccharides (HMOs) are complex carbohydrate components of human breast milk that exhibit plentiful benefits on infant health. However, ...

Analysis and Specification of Starch Granule Size Distributions

Starch from all plant sources are made up of granules in a range of sizes and shapes having different occurrence frequencies, i.e., exhibiting a size and a shape distribution. Starch granule size data determined using several types of particle sizing techniques are often problematic due to poor reproducibility or lack of statistical significance resulting from some insurmountable systematic errors, including sensitivity to granule shapes and limits of granule-sample sizes. We outlined a procedure for reproducible and statistically valid determinations of starch granule size distributions using the electrical sensing zone technique, and for specifying the determined granule lognormal size distributions using an adopted two-parameter multiplicative form with improved accuracy and comparability. It is applicable to all granule sizing analyses of gram-scale starch samples, and, therefore, could facilitate studies on how starch granule sizes are molded by the starch biosynthesis apparatus and mechanisms; and how they impact properties and functionality of starches for food and industrial uses. Representative results are presented from replicate analyses of granule size distributions of sweetpotato starch samples using the outlined procedure. We further discussed several key technical aspects of the procedure, especially, the multiplicative specification of granule lognormal size distributions and some technical means for overcoming frequent aperture blockage by granule aggregates.

Presented here is a procedure for reproducible and statistically valid determinations of starch granule size distributions, and for specifying the determined granule lognormal size distributions using a two-parameter multiplicative form. It is applicable to all granule sizing analyses of gram-scale starch samples for plant and food science research. &#160;

淀粉颗粒大小分布的分析和规格

Starch from all plant sources are made up of granules in a range of sizes and shapes having different occurrence frequencies, i.e., exhibiting a size and ...