Post on 19-Aug-2020
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List of Figures
Figure 1.1: Chemical structures of common phenolic bioactive compounds in Noni.
(Source: Chan-Blanco et al., 2006.)............................................................................. 5
Figure 2.1: Reaction of anti-oxidant compound with DPPH (Prakash et al., 2001).. 32
Figure 2.2: DPPH radical scavenging activity for Hawaiian and Micronesian
fermented Noni........................................................................................................... 34
Figure 2.3: EC50 values for Hawaiian and Micronesian Noni. ................................. 35
Figure 2.4 a): EC50 values for Hawaiian and Micronesian Noni and Maximum
DPPH scavenging activity…………………………………………………………..36
Figure 2.4 b): Ferric reducing anti-oxidant potential for both varieties of Noni. ...... 37
Figure 2.5: Total phenolic content for the Micronesian and Hawaiian variety. ........ 39
Figure 3.1: The Renin – Angiotensin System (Erdmann, et al., 2008) ...................... 42
Figure 3.2: Chromatogram for the ACE inhibitory reaction [Time in minutes]........ 47
Figure 3.3: ACE inhibitory activity for Hawaiian Noni and Micronesian Noni.
Captopril is the positive control ................................................................................. 49
Figure 4.1: α-amylase inhibitory activity for Hawaiian Noni and Micronesian Noni.
.................................................................................................................................... 64
Figure 4.2: α-glucosidase inhibitory activity for Hawaiian Noni and Micronesian Noni.
.................................................................................................................................... 67
Figure 4.3: Minimally modified anti-glycation activity for Hawaiian Noni and
Micronesian Noni....................................................................................................... 69
Figure 4.4: Protein – bound fluorescent AGE inhibition for Hawaiian Noni and
Micronesian Noni....................................................................................................... 70
1
O
O
OH
OH
OH
OOH
12
O
O
O CH3
OH
O
OH
1
OH
OH
O
O
OH
CH32
OH
O
O
OH
OH
3
O OOH
O
CH3
11
O
OH
OH
OH
OOH
OH
10
O
OH
OH
O
9
O
O
OH
OH
OH
7
O
O
OH
OH
4
O
O
OH
OOH
OH
5
O
OH
O O
CH3
8
O
O OH
OH
OH
6
Anti-oxidant
DPPH
36
Figure 2.4 a): EC50 values for Hawaiian and Micronesian Noni and Maximum
DPPH scavenging activity. Data presented as mean ± SD, N = 3.
2.3.3 Anti-oxidant activity using FRAP Analysis
Anti-oxidative activity can also be measured by FRAP assay (Benzie and Strain,
1999). FRAP assay uses anti-oxidants as reductants in a redox-linked colorimetric
method. The ferric reducing anti-oxidant power is based on the reduction of a ferroin
analog at acidic condition. In this assay, Tripyridyltriazine Fe (TPTZ) 3+ is reduced to
Fe (TPTZ) 2+ thus generating a blue colour and the intensity is measured at 595 nm
(Benzie and Strain, 1996). The reducing power thus reflects the anti-oxidants ability
and detects the anti-oxidants with a redox potential of < 0.7 V (Prior et al., 2005). The
reaction is non-specific, in that any half reaction that has a lower redox potential will
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change the ferrous reaction Fe (III) to Fe (II). The change in absorbance is therefore,
directly related to the total anti-oxidant power of the electron donating anti-oxidants
present in the reaction mixture. The anti-oxidant power of the Noni juice was measured
for both varieties over 8 weeks of fermentation. Figure 2.3 shows the anti-oxidant
potential of the fermented Noni juice for the two fruit varieties.
Figure 2.4 b): Ferric reducing anti-oxidant potential for both varieties of Noni.Data presented as mean ± SD, N = 3. # p<0.01; ### p<0.001 are significantly
different when compared between the varieties on respective weeks
The FRAP assay showed that the anti-oxidative potential for the Hawaiian and
Micronesian Noni. The Hawaiian variety of Noni showed relatively similar activity at
all the fermentation weeks. The antioxidant potential of fermented noni juice (2-8
weeks) are similar to unfermented noni juice (0 weeks). However, the Micronesian
variety Noni showed higher anti-oxidant potential than Hawaiian variety Noni at 4 and
6 weeks. The anti-oxidant potential of the Micronesian Noni is higher as compared to
the Hawaiian variety at p < 0.01 and both varieties showed the activity within a similar
range.
0 2 4 6 80
1 0
2 0
3 0
W e e k s
gGA
E/m
g
M ic ro n e s ia n
H aw a iia n * * *
* **
# # #
# ## #
0
10
20
30
40
50
60
70
80
90
100
0 2 4 6 8 Standard
% In
hibi
tion
Weeks of fermentation
Fermented Noni extracts on α-amylase activity
Micronesian Variety
Hawaiian Variety
Acarbose
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
10 20 40 60 80 100 500
% In
hibi
tion
Concentration (ug/mL)
Fermented Noni extracts on α-glucosidase activity
Micronesian-Week 6
Micronesian-Week 8
Hawaiian-Week 6
Hawaiian-Week 8
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
AG (30 uM) 0 2 4 6 8
% In
hibi
tion
Weeks of Fermentation
Minimally modified antiglycation activity
Micronesian Noni
Hawaiian
0 2 4 6 80
2 0
4 0
6 0
8 0
1 0 0
W e e k s
% In
hib
itio
n
M ic ro n e s ia n
H aw a iia n
* **
*
* ** *
+ +
+ +
+ +
# #
#