Effect of Saccharomyces cerevisiae Fermentation Process …
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preparation, the sample was subjected to centrifugation at 6000 rpm for 15 min and
the supernatant was collected and stored at 18 °C until use.
However, for fermented preparation the sample was inoculated with S. cerevisiae.
The fermentation process was then carried out for a period of 24 h at 35 °C. The
sample was subjected to centrifugation at 6000 rpm for 15 min. The supernatant was
collected and stored at 18 °C until use.
2.3 Phytochemical Screening
The phytochemical screening was assessed by using a standard procedure described
by Bekal et al. (2015). Phytochemical screening was done to identify the major
phytochemical constituents such as tannins, saponins, flavonoids, phenols, alkaloids
and glycosides.
2.4 Determination of Total Phenolic (TPC)
The determination of total phenolic contents (TPC) of fermented and unfermented
extracts was based on Skerget et al. (2005). An aliquot of the extract (0.2 ml) was
mixed with 2.5 ml of Folin-Ciocalteu reagent and 2 ml of Na 2 CO 3 (7.5%) and
incubated for 30 min at room temperature. Absorbance was measured at 760 nm
using distilled water as blank. The amounts of TPC were calculated using gallic acid
for calibration.
2.5 Determination of Total Flavonoid (TFC)
Flavonoids in flaxseed extracts were quantified by AlCl 3 method described by Sultana
et al. (2007). Total flavonoid content was expressed as catechin equivalents (CE).
Briefly, 1 ml of extract, 5 ml of distilled water, 0.3 ml of 5% NaNO 2 were added and
mixed well, after 5 min 0.6 ml of 10% AlCl 3 was added. After another 5 min 1 ml
of 1 M NaOH was added and volume made up to 10 ml with distilled water. The
solution was mixed well. Absorbance was recorded at 510 nm.
2.6 Free Radical Scavenging Activity Using DPPH Method
The free radical scavenging activity of the extracts was measured by 1, 1-diphenyl2-picrylhydrazyl (DPPH) method (Kaur et al. 2008). In a brief, 0.1 Mm solution of
DPPH was prepared. 1 ml DPPH working solution was mixed with 1 ml of extract
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preparation, the sample was subjected to centrifugation at 6000 rpm for 15 min and
the supernatant was collected and stored at 18 °C until use.
However, for fermented preparation the sample was inoculated with S. cerevisiae.
The fermentation process was then carried out for a period of 24 h at 35 °C. The
sample was subjected to centrifugation at 6000 rpm for 15 min. The supernatant was
collected and stored at 18 °C until use.
2.3 Phytochemical Screening
The phytochemical screening was assessed by using a standard procedure described
by Bekal et al. (2015). Phytochemical screening was done to identify the major
phytochemical constituents such as tannins, saponins, flavonoids, phenols, alkaloids
and glycosides.
2.4 Determination of Total Phenolic (TPC)
The determination of total phenolic contents (TPC) of fermented and unfermented
extracts was based on Skerget et al. (2005). An aliquot of the extract (0.2 ml) was
mixed with 2.5 ml of Folin-Ciocalteu reagent and 2 ml of Na 2 CO 3 (7.5%) and
incubated for 30 min at room temperature. Absorbance was measured at 760 nm
using distilled water as blank. The amounts of TPC were calculated using gallic acid
for calibration.
2.5 Determination of Total Flavonoid (TFC)
Flavonoids in flaxseed extracts were quantified by AlCl 3 method described by Sultana
et al. (2007). Total flavonoid content was expressed as catechin equivalents (CE).
Briefly, 1 ml of extract, 5 ml of distilled water, 0.3 ml of 5% NaNO 2 were added and
mixed well, after 5 min 0.6 ml of 10% AlCl 3 was added. After another 5 min 1 ml
of 1 M NaOH was added and volume made up to 10 ml with distilled water. The
solution was mixed well. Absorbance was recorded at 510 nm.
2.6 Free Radical Scavenging Activity Using DPPH Method
The free radical scavenging activity of the extracts was measured by 1, 1-diphenyl2-picrylhydrazyl (DPPH) method (Kaur et al. 2008). In a brief, 0.1 Mm solution of
DPPH was prepared. 1 ml DPPH working solution was mixed with 1 ml of extract