I would like to acknowledge Dr. Thomas Rademacher for providing the transgenic tobacco seeds and Ibrahim Al Amedi for cultivating the tobacco plants. I wish to thank Dr. Richard M Twyman for editorial assistance and Prof. Dr. Rainer Fischer for fruitful discussions. This work was funded in part by the European Research Council Advanced Grant ''Future-Pharma'', proposal number 269110, the Fraunhofer-Zukunftsstiftung (Fraunhofer Future Foundation) and the Fraunhofer-Gesellschaft Internal Programs under Grant No. Attract 125-600164.

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ההיבט החשוב ביותר שיש להביא בחשבון בעת הגדרת איילה לאפיין הפתתה חלקיקים הוא שהתכנון חייב עקרונית להיות מסוגל לזהות ולתאר את ההשפעות הצפויות או אפשריות 36,38, למשל השפעת pH, סוג הפולימר וריכוז פולימר 16. לכן, חשוב להעריך את החלק היחסי של מרחב תכנון (FDS) לפני...

צמחים נמצאים בשימוש נרחב כדי לייצר סחורות מזון כגון מיצי פרות, אבל הם יכולים גם להיות מפותחים כמו פלטפורמות לייצור מוצרי הביו-פרמצבטיקה בעלי ערך גבוה יותר 1-3. בשני המקרים, עיבוד במורד הזרם (DSP) לעתים קרובות מתחיל עם החילוץ של נוזלים מרקמות כגון עלים או פירות, ואחריו ההבהרה של תמציות-לאדן החלקיקים 4,5. לייצור תרופות ביולוגיים, העלויות של DSP יכולות להסביר עד 80% מעלויות הייצור הכוללים 6,7 וזאת חלק משקפת את ההווה נטל חלקיקים גבוהים תמציות הוכנו בשיטות משבשות כגון המגון להב מבוסס 8,9 . למרות הבחירה הרציונלית של שכבות מסננות כדי להתאים את התפלגות גודל חלקיקים בתמצית יכולה להגדיל את הקיבולת מסננת ולהפחית עלויות 10,11, השיפור לא יכול לחרוג מתקרת הקיבולת המוחלטת המוגדרת במספר החלקיקים חייבים להישמר לכליחידת שטח מסנן להשיג הבהרה. התקרה ניתן להרים אם פחות חלקיקים מגיעים לפני השטח של מסנני משובחי הרכבת הסינון, זו יכולה להיות מושגת אם חלקיקים מפוזרים הם מעורבבים עם פולימרים המכונים flocculants המקדמים צבירה להקים flocs הגדול 12. flocs כזה ניתן להיעזר הזרם עוד יותר על ידי מסנני שק גס ופחות יקר, הפחתת הנטל חלקיק שהגיע עדינה ומסננים עומק יקר יותר. חייבים להיות פולימרי פרופילי בטיחות מתאימים ליישומים שלהם, למשל עבור הביופרמצבטיקה הם צריכים להיות תואמים ייצור נאות (GMP), ובדרך כלל הם חייבים להיות מסה טוחנת&gt; 100 kDa והוא יכול גם להיות ניטראלי או טעון 13. בעוד flocculants הניטראלי פועל בדרך כלל על ידי cross-linking חלקיקים מפוזרים גרימת הצבירה שלהם ויצירת flocs בקטרים&gt; 1 מ&quot;מ 11, פולימרים טעונים לנטרל את המטען של דחלקיקי ispersed, הפחתת המסיסות שלהם ובכך גרמו ממטרים 14. הפתתה ניתן לשפר על ידי התאמת פרמטרים כגון חיץ pH או מוליכות, ואת סוג הפולימר או ריכוז, כדי להתאים את המאפיינים של תמצית 15,16. תמציות טבק pretreated עם 0.5-5.0 גרם ל -1 polyethylenimine (PEI), גדול יותר מאשר גידול פי 2 ב קיבולת עומק מסנן נמסר בתהליך 100-L טייס מידה. עלות פולימר זה פחות מ -10 € קילו -1 כך החדרתו תהליך הביאה לחיסכון בעלויות של כ -6,000 € עבור מסננים מתכלה לכל תצווה 16 או אפילו יותר כאשר הוא משולב עם עזרי מסנן מבוסס תאי 17. אף על פי כן, מודלים חזויים נדרשים להעריך את ההטבות כלכליות אפריורי של flocculants כי הכללה יכול לדרוש צעדי אחיזה של 15-30 דקות 16,18, וכתוצאה מכך עלויות השקעה נוספות לאחסוןטנקים. עם זאת, אין כיום מודלים מכניסטית זמינים שיכול לחזות את התוצאה של ניסויים כאלה בשל האופי המורכב של הפתתה. לכן, מתאים יותר עיצוב של ניסויים (DOE) הגישה 19 פותחה כמתואר במאמר זה. פרוטוקול עבור הליך האיילה הכללי לאחרונה פורסם 20. מכשירים בקנה מידה קטנה זמינים כעת עבור הקרנת התפוקה הגבוהה של תנאים הפתתה 21. עם זאת, מכשירים אלה לא יכולים לדמות תנאים מציאותיים במהלך הפתתה של תמציות צמחים כי ממד כלי התגובה (~ 7 מ&quot;מ עבור בארות על צלחת 96-היטב) ואת החלקיקים או flocs יכול להיות פחות מ בסדר גודל זה מזה. הדבר עלול להשפיע על ערבוב דפוסים ובכך כוח הניבוי של המודל. יתר על כן, זה יכול להיות קשה כדי להקטין תהליכים מעורבים ממטרים עקב שינויים שאינו ליניארי בהתנהגות ערבוב STA המשקעbility 22. לכן, במאמר זה מתאר מערכת הקרנת ספסל העליונה בקנה מידה עם תפוקה של 50-75 דגימות ליום, מניב תוצאות שאינן מדרגים מכרך התגובה הראשוני 20 מיליליטר לתהליך 100 L טייס מידת 16. בשילוב עם גישת איילה, זה מאפשר מודלים המנבאים לשמש אופטימיזציה תהליך ותיעוד כחלק מושג איכות-ידי עיצוב. השיטה המתוארת להלן עשויה גם להיות מותאמת ל תרופות ביולוגיות מיוצרות בתא תהליכי התרבות מבוססת, שבו flocculants גם נבחנים ככלי לחיסכון בעלויות 23. זה יכול גם לשמש מודל המשקע של חלבוני היעד מ תמצית גולמית כחלק מאסטרטגית טיהור, כפי שמודגם עבור β-glucuronidase מיוצר קנולה, תירס וסויה 24,25. תיאור מפורט של תכונות flocculant ניתן למצוא במקום אחר 16,26 וזה חשוב לוודא כי concentr הפולימרations הם או רעיל או מתחת לרמות מזיקות במוצר הסופי 11.

<table><tbody><tr><td>2100P Portable Turbidimeter</td><td>Hach</td><td>4650000</td><td>Turbidimeter</td></tr><tr><td>2G12 antibody</td><td>Polymun</td><td>AB002</td><td>Reference antibody</td></tr><tr><td>Biacore T200</td><td>GE Healthcare</td><td>28-9750-01</td><td>SPR device</td></tr><tr><td>BP-410</td><td>Furh</td><td>2632410001</td><td>Bag filter</td></tr><tr><td>Catiofast VSH</td><td>BASF</td><td>79002360</td><td>Flocculating agent</td></tr><tr><td>Centrifuge 5415D</td><td>Eppendorf</td><td>5424 000.410</td><td>Centrifuge</td></tr><tr><td>Centrifuge tube 15 ml</td><td>Labomedic</td><td>2017106</td><td>Reaction tube</td></tr><tr><td>Centrifuge tube 50 ml self-standing</td><td>Labomedic</td><td>1110504</td><td>Reaction tube</td></tr><tr><td>Chitosan</td><td>Carl Roth GmbH</td><td>5375.1</td><td>Flocculating agent</td></tr><tr><td>Design-Expert(R) 8</td><td>Stat-Ease, Inc.</td><td>n.a.</td><td>DoE software</td></tr><tr><td>Disodium phosphate</td><td>Carl Roth GmbH</td><td>&amp;nbsp;4984.3&amp;nbsp;</td><td>Media component</td></tr><tr><td>Ferty 2 Mega</td><td>Kammlott</td><td>5.220072</td><td>Fertilizer</td></tr><tr><td>Forma -86C ULT freezer</td><td>ThermoFisher</td><td>88400</td><td>Freezer</td></tr><tr><td>Greenhouse</td><td>n.a.</td><td>n.a.</td><td>For plant cultivation</td></tr><tr><td>Grodan Rockwool Cubes 10 x 10 cm</td><td>Grodan</td><td>102446</td><td>Rockwool block</td></tr><tr><td>HEPES</td><td>Carl Roth GmbH</td><td>9105.3</td><td>Media component</td></tr><tr><td>K700P 60D</td><td>Pall</td><td>5302305</td><td>Depth filter layer</td></tr><tr><td>KS50P 60D</td><td>Pall</td><td>B12486</td><td>Depth filter layer</td></tr><tr><td>Miracloth</td><td>Labomedic</td><td>475855-1R</td><td>Filter cloth</td></tr><tr><td>MultiLine Multi 3410 IDS</td><td>WTW</td><td>WTW_2020</td><td>pH meter / conductivity meter</td></tr><tr><td>Osram cool white 36 W</td><td>Osram</td><td>4930440</td><td>Light source</td></tr><tr><td>Phytotron</td><td>Ilka Zell</td><td>n.a.</td><td>For plant cultivation</td></tr><tr><td>Polymin P</td><td>BASF</td><td>79002360</td><td>Flocculating agent</td></tr><tr><td>POLYTRON PT 6100 D</td><td>Kinematica</td><td>11010110</td><td>Homogenization device with custom blade tool</td></tr><tr><td>Protein A</td><td>Life technologies</td><td>10-1006</td><td>Antibody binding protein</td></tr><tr><td>Sodium chloride</td><td>Carl Roth GmbH</td><td>P029.2</td><td>Media component</td></tr><tr><td>Synergy HT</td><td>BioTek</td><td>SIAFRT</td><td>Fluorescence plate reader</td></tr><tr><td>TRIS</td><td>Carl Roth GmbH</td><td>4855.3</td><td>Media component</td></tr><tr><td>Tween-20</td><td>Carl Roth GmbH</td><td>9127.3</td><td>Media component</td></tr><tr><td>VelaPad 60</td><td>Pall</td><td>VP60G03KNH4</td><td>Filter housing</td></tr><tr><td>Zetasizer Nano ZS</td><td>Malvern</td><td>ZEN3600</td><td>DLS particle size distribution measurement</td></tr></tbody></table>

procedure to evaluate the efficiency of flocculants for the removal of dispersed particles from plant extracts

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used as manufacturing platforms for added-value products such as biopharmaceuticals. In both cases, liquid plant extracts may need to be clarified to remove particulates. Optimal clarification reduces the costs of filtration and centrifugation by increasing capacity and longevity. This can be achieved by introducing charged polymers known as flocculants, which cross-link dispersed particles to facilitate solid-liquid separation. There are no mechanistic flocculation models for complex mixtures such as plant extracts so empirical models are used instead. Here a design-of-experiments procedure is described that allows the rapid screening of different flocculants, optimizing the clarification of plant extracts and significantly reducing turbidity. The resulting predictive models allow the identification of robust process conditions and sets of polymers with complementary properties, e.g. effective flocculation in extracts with specific conductivities. The results presented for tobacco leaf extracts can easily be adapted to other plant species or tissues and will thus facilitate the development of more cost-effective downstream processes for commodities and plant-derived pharmaceuticals.

הפתתה של תמצית טבק עם פולימרים שונים השיטה המתוארת לעיל שמשה בהצלחה לפתח תהליך של הפתתה של תמציות טבק במהלך הייצור של נוגדנים חד שבטיים (HIV-נטרול נוגדני 2G12) לבין חלבון פלואורסצנטי (DsRed) (איור...

Watch this Scientific Journal Video about Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts at JoVE.com

Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts

The design-of-experiments procedure presented here allows the evaluation of different flocculants in terms of their ability to aggregate dispersed particles in plant extracts, thus reducing turbidity and the costs of downstream processing.

נוהל כדי להעריך את היעילות של flocculants להרחקת מפוזרי חלקיקים מן תמציות צמחים

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used ...

procedure-to-evaluate-efficiency-flocculants-for-removal-dispersed

Research

JoVE Journal

Biology

8.9K Views.  Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e. V.. The design-of-experiments procedure presented here allows the evaluation of different flocculants in terms of their ability to aggregate dispersed particles in plant extracts, thus reducing turbidity and the costs of downstream processing.

Video: Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts

A Small Volume Procedure for Viral Concentration from Water

Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to identify optimal parameters for virus concentration. Viruses can be concentrated from water using filtration (electropositive, electronegative, glass wool or size exclusion), followed by secondary concentration with beef extract to release viruses from filter surfaces, and finally tertiary concentration resulting in a 5-30 ml volume virus concentrate. In order to identify optimal concentration procedures, two different electropositive filters were evaluated (a glass/cellulose filter [1MDS] and a nano-alumina/glass filter [NanoCeram]), as well as different secondary concentration techniques; the celite technique where three different celite particle sizes were evaluated (fine, medium and large) followed by comparing this technique with that of the established organic flocculation method. Various elution additives were also evaluated for their ability to enhance the release of adenovirus (AdV) particles from filter surfaces. Fine particle celite recovered similar levels of AdV40 and 41 to that of the established organic flocculation method when viral spikes were added during secondary concentration. The glass/cellulose filter recovered higher levels of both, AdV40 and 41, compared to that of a nano-alumina/glass fiber filter. Although not statistically significant, the addition of 0.1% sodium polyphosphate amended beef extract eluant recovered 10% more AdV particles compared to unamended beef extract.

An approach was developed for identifying optimal viral concentration conditions for small volume water samples using spikes of human adenovirus. The techniques described here are used to identify concentration parameters for other viral targets, and applied to large-scale viral concentration experimentation.

נוהל נפח קטן לריכוז נגיפי ממים

Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to ...

Environment

Extraction and Characterization of Surfactants from Atmospheric Aerosols

Surface-active compounds, or surfactants, present in atmospheric aerosols are expected to play important roles in the formation of liquid water clouds in the Earth&#39;s atmosphere, a central process in meteorology, hydrology, and for the climate system. But because specific extraction and characterization of these compounds have been lacking for decades, very little is known on their identity, properties, mode of action and origins, thus preventing the full understanding of cloud formation and its potential links with the Earth&#39;s ecosystems.
In this paper we present recently developed methods for 1) the targeted extraction of all the surfactants from atmospheric aerosol samples and for the determination of 2) their absolute concentrations in the aerosol phase and 3) their static surface tension curves in water, including their Critical Micelle Concentration (CMC). These methods have been validated with 9 references surfactants, including anionic, cationic and non-ionic ones. Examples of results are presented for surfactants found in fine aerosol particles (diameter &#60;1 &#956;m) collected at a coastal site in Croatia and suggestions for future improvements and other characterizations than those presented are discussed.

Methods are presented for the targeted extraction of surfactants present in atmospheric aerosols and the determination of their absolute concentrations and surface tension curves in water, including their Critical Micelle Concentration (CMC).

הפקת ואפיון של חומרים פעילי שטח מ אירוסולים באטמוספירה

Surface-active compounds, or surfactants, present in atmospheric aerosols are expected to play important roles in the formation of liquid water clouds in ...

Determination of the Settling Rate of Clay/Cyanobacterial Floccules

The mechanisms underpinning the deposition of fine-grained, organic-rich sediments are still largely debated. Specifically, the impact of the interaction of clay particles with reactive, planktonic cyanobacterial cells to the sedimentary record is under studied. This interaction is a potentially major contributor to shale depositional models. Within a lab setting, the flocculation and sedimentation rates of these materials can be examined and measured in a controlled environment. Here, we detail a protocol for measuring the sedimentation rate of cyanobacterial/clay mixtures. This methodology is demonstrated through the description of two sample experiments: the first uses kaolin (a dehydrated form of kaolinite) and Synechococcus sp. PCC 7002 (a marine coccoid cyanobacteria), and the second uses kaolin and Synechocystis sp. PCC 6803 (a freshwater coccoid cyanobacteria). Cyanobacterial cultures are mixed with varying amounts of clay within a specially designed tank apparatus optimized to allow continuous, real-time video and photographic recording. The sampling procedures are detailed as well as a post-collection protocol for precise measurement of chlorophyll a from which the concentration of cyanobacterial cells remaining in suspension can be determined. Through experimental replication, a profile is constructed that displays sedimentation rate.

The interaction and sedimentation of the clay and bacterial cells within the marine realm, observed in natural environments, can be best investigated in a controlled lab environment. Here, we describe a detailed protocol, which outlines a novel method for measuring the sedimentation rate of clay and cyanobacterial floccules.

קביעת שיעור ליישוב של קליי/Cyanobacterial Floccules

The mechanisms underpinning the deposition of fine-grained, organic-rich sediments are still largely debated. Specifically, the impact of the interaction ...

Combined Size and Density Fractionation of Soils for Investigations of Organo-Mineral Interactions

Combined size and density fractionation (CSDF) is a method used to physically separate soil into fractions differing in particle size and mineralogy. CSDF relies on sequential density separation and sedimentation steps to isolate (1) the free light fraction (uncomplexed organic matter), (2) the occluded light fraction (uncomplexed organic matter trapped in soil aggregates) and (3) a variable number of heavy fractions (soil minerals and their associated organic matter) differing in composition. Provided that the parameters of the CSDF (dispersion energy, density cut-offs, sedimentation time) are properly selected, the method yields heavy fractions of relatively homogeneous mineral composition. Each of these fractions is expected to have a different complexing ability towards organic matter, rendering this a useful method to isolate and study the nature of organo-mineral interactions. Combining density and particle size separation brings an improved resolution compared to simple size or density fractionation methods, allowing the separation of heavy components according to both mineralogy and size (related to surface area) criteria. As is the case for all physical fractionation methods, it may be considered as less disruptive or aggressive than chemically-based extraction methods. However, CSDF is a time-consuming method and furthermore, the quantity of material obtained in some fractions can be limiting for subsequent analysis. Following CSDF, the fractions may be analyzed for mineralogical composition, soil organic carbon concentration and organic matter chemistry. The method provides quantitative information about organic carbon distribution within a soil sample and brings light to the sorptive capacity of the different, naturally-occurring mineral phases, thus providing mechanistic information about the preferential nature of organo-mineral interactions in soils (i.e., which minerals, what type of organic matter).

Combined size and density fractionation (CSDF) is a method to physically separate soil into fractions differing in texture (particle size) and mineralogy (density). The purpose is to isolate fractions with different reactivities towards soil organic matter (SOM), in order to better understand organo-mineral interactions and SOM dynamics.

גודל משולב של צפיפות Fractionation של קרקעות החקירות של האינטראקציות אורגניות-מינרליים

Combined size and density fractionation (CSDF) is a method used to physically separate soil into fractions differing in particle size and mineralogy. CSDF ...

Capture of Environmental DNA (eDNA) from Water Samples by Flocculation

The analysis of environmental DNA (eDNA) has become a widely used approach to problem solving in species management. The detection of cryptic species including invasive and (or) species at risk is the goal, typically accomplished by testing water and sediment for the presence of characteristic DNA signatures. Reliable and efficient procedures for the capture of eDNA are required, especially those that can be performed easily in the field by personnel with limited training and citizen scientists. The capture of eDNA using membrane filtration is widely used currently. This approach has inherent issues that include the choice of filter material and porosity, filter fouling, and time required on site for the process to be performed. Flocculation offers an alternative that can be easily implemented and applied to sampling regimes that strive to cover broad territories in limited time.

<meta charset="utf8"></head><body>לכידת דנ"א סביבתי מדגימות מים על ידי פלוקולציה

Environmental DNA (eDNA) is typically captured from water samples using alcohol precipitation, filtration, or flocculation. Presented here is an alternative protocol that uses lanthanum chloride to enable collection of dissolved and particulate-bound nucleic acids from water samples containing eukaryotic cells, prokaryotic cells, and virus.

לכידת DNA סביבתי (eDNA) מדגימות מים על ידי פלוקולציה

The analysis of environmental DNA (eDNA) has become a widely used approach to problem solving in species management. The detection of cryptic species ...

Activated Cross-linked Agarose for the Rapid Development of Affinity Chromatography Resins - Antibody Capture as a Case Study

The purification of monoclonal antibodies (mAbs) is commonly achieved by Protein A affinity chromatography, which can account for up to 25% of the overall process costs. Alternative, cost-effective capture steps are therefore valuable for industrial-scale manufacturing, where large quantities of a single mAb are produced. Here we present a method for the immobilization of a DsRed-based epitope ligand to a cross-linked agarose resin allowing the selective capture of the HIV-neutralizing antibody 2F5 from crude plant extracts without using Protein A. The linear epitope ELDKWA was first genetically fused to the fluorescent protein DsRed and the fusion protein was expressed in transgenic tobacco (Nicotiana tabacum) plants before purification by immobilized metal-ion affinity chromatography. Furthermore, a method based on activated cross-linked agarose was optimized for high ligand density, efficient coupling and low costs. The pH and buffer composition and the soluble ligand concentration were the most important parameters during the coupling procedure, which was improved using a design-of-experiments approach. The resulting affinity resin was tested for its ability to selectively bind the target mAb in a crude plant extract and the elution buffer was optimized for high mAb recovery, product activity and affinity resin stability. The method can easily be adapted to other antibodies with linear epitopes. The new resins allow gentler elution conditions than Protein A and could also reduce the costs of an initial capture step for mAb production.

In this procedure, a DsRed-based epitope ligand is immobilized to produce a highly selective affinity resin for the capture of monoclonal antibodies from crude plant extracts or cell culture supernatants, as an alternative to Protein A.

הופעל מקושרת צולבת מקושרת לפיתוח מהיר של שרפים כרומטוגרפיה של אהדה-לכידת נוגדן כמחקר מקרה

The purification of monoclonal antibodies (mAbs) is commonly achieved by Protein A affinity chromatography, which can account for up to 25% of the overall ...

Biochemistry

הערכת מיני בוטנים פראיים לעמידות להצטברות אפלטוקסין

Non-destructive SPE-UPLC-based Quantification of Aflatoxins and Stilbenoid Phytoalexins in Single Peanut (Arachis spp.) Seeds

Aflatoxins are highly carcinogenic secondary metabolites of some fungal species, particularly Aspergillus flavus. Aflatoxins often contaminate economically important agricultural commodities, including peanuts, posing a high risk to human and animal health. Due to the narrow genetic base, peanut cultivars demonstrate limited resistance to fungal pathogens. Therefore, numerous wild peanut species with tolerance to Aspergillus have received substantial consideration by scientists as sources of disease resistance.
Exploring plant germplasm for resistance to aflatoxins is difficult since aflatoxin accumulation does not follow a normal distribution, which dictates the need for the analyses of thousands of single peanut seeds. Sufficiently hydrated peanut (Arachis spp.) seeds, when infected by Aspergillus species, are capable of producing biologically active stilbenes&#160;(stilbenoids) that are considered defensive phytoalexins. Peanut stilbenes inhibit fungal development and aflatoxin production. Therefore, it is crucial to analyze the same seeds for peanut stilbenoids to explain the nature of seed resistance/susceptibility to the Aspergillus invasion. None of the published methods offer single-seed analyses for aflatoxins and/or stilbene phytoalexins.
We attempted to fulfill the demand for such a method that is environment-friendly, uses inexpensive consumables, and is sensitive and selective. In addition, the method is non-destructive since it uses only half of the seed and leaves the other half containing the embryonic axis intact. Such a technique allows germination and growth of the peanut plant to full maturity from the same seed used for the aflatoxin and stilbenoid analysis. The integrated part of this method, the manual challenging of the seeds with Aspergillus, is a limiting step that requires more time and labor compared to other steps in the method. The method has been used for the exploration of wild Arachis germplasm to identify species resistant to Aspergillus and to determine and characterize novel sources of genetic resistance to this fungal pathogen.

Author Spotlight: Quantification of aflatoxins and phytoalexins in peanut seeds to identify genetic resistance against Aspergillus

We demonstrate a medium-throughput method for quantification of aflatoxins and stilbenoid phytoalexins in single peanut seeds using ultra performance liquid chromatography. This method was specifically developed for the analyses of wild Arachis species challenged by the aflatoxigenic Aspergillus species.

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כימות מבוסס SPEP-UPLC לא הרסני של אפלטוקסינים ופיטואלכסינים סטילבנואידים בבוטנים בודדים (Arachis spp.) זרעים

כימות מבוסס SPEP-UPLC לא הרסני של אפלטוקסינים ופיטואלכסינים סטילבנואידים בבוטנים בודדים (Arachis spp.) זרעים

כימות מבוסס SPEP-UPLC לא הרסני של אפלטוקסינים ופיטואלכסינים סטילבנואידים בבוטנים בודדים (Arachis spp.) זרעים