What is the best mobile phase for isolation of compounds from Aloe vera flower extract?

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Enzyme activity not working?

I am trying to do an enzyme assay using Wild type enzyme the protocol involves tris buffer pH 8, MgCl2, S-adenosyl methionine, Substrate, and I inititate the reaction with my enzyme, but after...

06 July 2019 6,793 3 View

Protein size decreases after mutation?

I am trying to express mutants of my protein whose size is 30 Kda... however following purification by Ni affinity column ... the SDS PAGE shows the mutants appearnig at size 20 Kda.. is there a...

04 May 2019 4,982 15 View

BL21 pLyss transformation and chloramphenicol?

Do I need to add chloramphenicol to LB agar media when trying to transform my plasmid into BL21 pLyss or I can add only the antibiotic of my plasmid?

04 May 2019 9,156 5 View

Why protien not eluted after changing buffer ?

II am currently working on a protien to be crystallized. The protien is bound to FAD, that's why when I purify the protein with Ni affinity column its colour was yellow . but surprisingly, after...

07 August 2018 4,263 4 View

How to make protien soluble during expression ?

I am trying to express and purify a protein after doing all the steps and purify using Ni affinity column but after doing the SDS PAGE I found that the amount of protein in the elute is very...

05 June 2018 8,503 6 View

Use of precukture ?

I want to ask why we always do a starter preculture step during protein expression ? Why don't we just start the main culture directly ?

04 May 2018 4,468 2 View

Protien not purified using ion exhange?

I am trying to purify a protein..First I run Ni affinity column and the protein was eluted with KPB pH7.9, imidazole 500mM and glycerol ..then I diluted with No Salt buffer containg 50mM TrisHCL...

04 May 2018 5,921 8 View

Chemical shift of acetyl gp?

what is the carbon nmr chemical shift of methyl gp in acetyl gp

11 December 2017 9,435 3 View

Methoxy gp on aromatic ring ?

If i have an aromatic ring with methoxy gp on it and 3 aromatic protons in ortho, meta and para position ..Is there an explanation for why the ortho proton appears at lower chemical shift than...

09 October 2017 8,721 3 View

Isolation of soil microbes?

I have cultured soil on 2 medium .. humic acid medium and chitin agar medium for culture of fungi and actinomycetes.. the question is .. how can i know the colon grown is fungi or bacteria .....

08 September 2017 4,071 6 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

16 June 2021 0 0 View

fatal error

16 June 2021 0 0 View

fatal error

16 June 2021 0 0 View

flexibility of polymers chain

effect of double bond on the flexibility of polymers

07 April 2021 0 0 View

Formulation of polymer color flakes

I am writing to request some information for making polymer color flakes. I would appreciate the help.

17 March 2021 0 0 View

What kind of fluid could I use for a pitfall trap that also does not invalidate molecular testing?

Hi, I want to start testing pitfall trap to obtain ants samples, but I need to conduct molecular analysis on those insects. So, what kind of fluid can I use? Ethanol expires too early and I need...

03 March 2021 5,978 5 View

How to increase a model accuracy ?

dear community, my model is based feature extraction from non stationary signals using discrete Wavelet Transform and then using statistical features then machine learning classifiers in order to...

03 March 2021 6,994 5 View