of all extracts have intense absorption bands in the 1700-1735 cm
-1
region, which is
characteristic of valence vibrations of ν C = O groups.
The UV-Vis spectroscopic method is one of the main methods of qualitative
determination of chemical compounds that are present in plant phyto-constituents. The
qualitative UV-Vis spectrum profile of the extract was selected at a wavelength from
200-800nm (Fig. 3). Different compounds have their characteristic wavelength of
maximum absorption. For propan-2-olextract the peak values of 313nm and 370nm
indicate terpenoid compounds and their derivatives. According to the GC/MS, the
extract contains the most abundant terpenoid compounds, namely geraniol and
nerolidol.
Figure 3. UV–visible absorbance spectra of apricot pomace extract
Anticorrosion and antioxidant capacity. The antioxidant activity of the extracts
was analysed by several methods, because evaluation of antioxidant properties of
plants cannot be carried out accurately by single universal method.
The total antioxidant activity was measured by phosphomolybdate method. The
phosphomolybdenum assay indicates the TAC of a sample analyse by the conversion
of Mo (VI) to MO (V), where the maximum absorbance of the green
phosphomolybdenum complex can be measured at 695 nm. This assay is simple and
inadequate of other antioxidant measurement employed. Also, it is a quantitative one,
since the antioxidant activity is expressed as the number of equivalent of ascorbic acid
(mg/g plant extract). The total antioxidant content was found to be 107,72±4,2 in 2-
propanol аpricot pomace extract (APE). The antioxidant activity of APE was evaluated
by measuring the ability of reducers (phenolic compounds) to convert a
Fe
3+
/ferricyanide complex to ferrous form by measuring the colour change from yellow
to ‘Perl Prussianblue’ at 700 nm.
The procedure of the determination of antioxidant activity in terms of reducing
powerwas followed. Fe (III) reduction is often used as an indicator of electron donating
activity, which is an important indicator of the phenolic antioxidant effect [7-8].
Extracts, which have reduction potential, react with potassium ferricyanide (Fe
3+
) to
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