Атты Республикалық ғылыми конференция материалдарының жинағы 4 сәуір 2022 жыл

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To find the value of the absolutely dry mass of the material, it is necessary to multiply the value of 
the taken air-dry weight by the dryness coefficient. 
2. Determination of permanganate antioxidant activity (Leventhal method) of plant raw 
materials 
Materials and equipment
: standard solution KMnO
4
(0,01 н)
,
H
2
SO
4
(2н), 100 ml beaker, 1 
ml mora pipette, burette, electric stove, 10 ml cylinder, filter paper. 
Analysis progress: 
Prepare an aqueous extract of vegetable raw materials: weigh 1 g of raw 
materials and pour it with 20 ml of water at a temperature of 30-400C, insist for 20 minutes, then 
filter through gauze into a glass of 100 ml. Extraction is repeated 2 more times. Collect the filtrate 
in a glass. Then select an aliquot of 10 ml in a flask for titration, add 10 ml of sulfuric acid and heat 
the flask 50-600C, then titrate 0.01 n with a standard solution of potassium permanganate until a 
pink color appears, which does not disappear for 30 seconds. Titration is repeated until convergent 
results are obtained. The calculation is carried out according to the formula:
 
а
V
KMnO
V
KMnO
С
1000
8
activity
t 
antioxidan
4
4
whereAntioxidant activity is oxidizability, mg of oxygen per liter of filtrate (mg of O2/l); 
C-normal concentration of potassium permanganate, mol/l; 
V – volume of potassium permanganate used for titration of the sample, ml; 
Va – volume of aliquot, ml; 
8-molar mass of oxygen equivalent, g/mol; 
1000 – conversionfactor. 
3. Determination of the acidity of plant raw materials 
Analysis progress:
We take 2 samples of plant materials weighing 2.5 g each (with an 
accuracy of 0.01 g). We place the sample in a glass and add 50 cm
3
of distilled water. Transfer to a 
porcelain cup and grind with a pestle until smooth. Transfer the resulting suspension into a conical 
flask. Mix the contents of the flask and add 3 drops of the indicator. The mixture is titrated with 
sodium hydroxide solution. Titration is carried out in drops evenly, with a slowdown at the end of 
the reaction with constant stirring of the contents of the flask until a clear pink color appears, which 
doesn’t disappear within 20-30 s.
 
If after the specified time the pink color disappears after shaking, then add another 3-4 drops 
of phenolphthalein solution. If a pink color appears, then the titration is considered complete. 
Measure the volume of the titrant used for titration. 
The result is determined in degrees of acidity using the formula 
Where: c (1 / 1NaOH) - titrant concentration, mol / dm
3
; 
V (NaOH) - volume of titrant used for titration, cm
3
; 
m - the mass of the sample; 
100 - conversion factor per 100 g of product. 
Round off the calculation result to the first decimal place. The final result is obtained as the 
arithmetic mean of two parallel measurements with a difference of no more than 0.2 degrees. 
4. Determination of the amount of flavonoids in plant raw materials 
Work progress:
take 4 weighed portions of 0.02 g of crushed raw materials. 10 ml of ethanol 
is added to each weighed portion and the first and second are kept for 30 minutes, the third and 
fourth for 45 minutes. Next, the obtained extracts are filtered and readings on KFK-3 in the 
wavelength range of 350-500 nm with a step of 10 nm. Build absorption spectrum, and it is 
determined by the analytical wavelength. If the selected wavelength is determined optical 
density.The content of the sum of flavonoids in terms of rutin (%) is calculated by the formula: 

11
X=
)
100
(
100
100
100
0
0
W
m
D
m
D
x
x
, where 
D
x
- the optical density of the test solution; 
D
0
-optical density of the RSO routine; (obtained from the teacher) 
m
x
- mass of raw materials (g); 
m
0
- mass of rutin in PCO (0.035 g); 
W - moisture content in plant raw materials (%) 
Based on the results obtained, a table is drawn up and the optimal time for the extraction of 
flavonoids is determined. 

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