Marah Al Taher

14 Questions 9 Answers 0 Followers

Questions related from Marah Al Taher

What is the correct way to prepare the positive control in 96-well microtiter MIC method?

I am using the 96-well MIC method. I diluted my plant extracts using 0.5% DMSO and I used Mueller Hinton broth to prepare the bacteria to achieve the correct log to start with but after that when...

20 November 2021 4,593 3 View

How long does it take to evaporate hexane?

I am using the rotary evaporator to evaporate n-hexane, I used 250ml of hexane and I am evaporating it at 40-45°C. How long will it approximately take?

11 October 2021 1,122 5 View

Flavonoid content is higher than phenol content. What could be the reason?

Good day, I am evaluating my plant's flavonoid and phenol content, and I have repeated the methods several times, and each time my flavonoid content has shown to be higher than the phenol...

24 September 2021 8,008 3 View

Why does a white precipitate form when performing the phenol test?

Hello, I am trying to test the phenol content in my methanolic plant extract, and I am testing two methods. Method 1: "One ml of 20% sodium carbonate solution was added to 1 ml of the phenolic...

21 September 2021 8,416 3 View

How do i prepare a 0.3M acetate buffer solution with a pH of 3.6?

I have acetic acid available (ml) and sodium acetate (g)

20 September 2021 1,167 4 View

How do I prepare 0.2 N Folin Ciocalteu reagent?

Good day, I want to prepare a 0.2 N of FCR, but I don't know how to do the calculation. Is it the same as (1:10 dilution or 10%)? I'd appreciate it if somebody can help. Thank you

20 September 2021 4,496 6 View

Why do most protocols call for and FCR ratio of 1:10?

I want to test the phenol content in my plant sample and I have chosen this method: "One ml of 20% sodium carbonate solution was added to 1 ml of the phenolic extract and incubated for 5 min. at...

18 September 2021 7,025 3 View

What is the best solvent to prepare phenol and flavonoid extracts?

Good day, I would like to know what is the best solvent to redissolve my extract in after extraction to obtain the best results. Thank you

16 September 2021 9,298 11 View

Flavonoid content analysis, Do I have to add water?

I am using this method to test the flavonoid content in my plant sample: "a sample (1.0 mL) of the liquid extract was mixed with 4 mL of Milli-Q water, and 0.3 mL of aqueous NaNO2 solution (5%...

15 September 2021 2,743 4 View

What is my final/stock concentration?

I used 0.5g of my dried plant seeds and dissolved them in 4ml 100% methanol, left them in a shaker overnight, then the next day, I centrifuged the extract, took the supernatant, and filtered it....

25 June 2021 3,468 3 View

Where can I find a standard and detailed protocol to use for the soxhlet extraction of oilseeds using n-hexane?

I am looking for a standard procedure to follow to extract oil from seeds using the soxhlet apparatus with n-hexane as the solvent. Thank you

19 May 2021 4,536 4 View

Can I use a water bath instead of a rotatory evaporator?

I am extracting oil from seeds using the soxhlet apparatus but all the procedures that I have seen call for a rotatory evaporator as the last step to evaporate the hexane. I don't have a rotatory...

19 May 2021 2,168 1 View

Is it possible if I use a heating magnetic stirrer for my soxhlet apparatus?

I want to extract oil using the soxhlet apparatus but I don't have a heating mantle. Is it possible if I use a heating magnetic stirrer?

16 March 2021 6,875 2 View

How to interpret Rarefaction curves? What does OTU mean?

Hello! I am trying to interpret this rarefaction curve as I am reading an article regarding the relationship between gut microbiota and diabetes, but I can't understand the figure. So if anyone...

26 April 2020 5,348 8 View