Anti-obesity Activity of Chlorophyll a from Spirulina (Arthrospira platensis) Through the Inhibition of Pancreatic Lipase Enzyme

Abstract

Obesity is considered a metabolic disease and a risk factor for other diseases. Spirulina (Arthrospira
platensis) a blue-green microalgae belonging to the cyanobacterium group is rich in chlorophyll a.
Spirulina extract has been shown to have pancreatic lipase inhibitory activity. This study aimed to
determine the anti-obesity activity of diethyl ether fraction and chlorophyll a from Spirulina extract.
Spirulina was extracted by maceration in methanol:acetone (7:3). The pigments including chlorophyll
were separated from the extract by fractionation with diethyl ether. Chlorophyll a was isolated from
the diethyl ether fraction by preparative thin layer chromatography (Prep-TLC). Chlorophyll a was
identified by ultra violet-visible (UV-Vis), and fourier transform infra-red (FTIR) spectrophotometry.
The anti-obesity activity of both the diethyl ether fraction, and chlorophyll a was evaluated by
pancreatic lipase inhibition assay in vitro. The anti-obesity activity of chlorophyll a was further
assessed in silico by molecular docking with human monoacylglycerol lipase enzyme (PDB ID:
5ZUN). Drug-likeness, and ADMET properties of chlorophyll a were also predicted. Results showed
that, both the diethyl ether fraction, and chlorophyll a from Spirulina extract exhibited anti-obesity
activity with IC
50
values of 167.16 ± 1.08 µg/mL, and 23.47 ± 0.83 µg/mL, respectively. The antiobesity
activity
of
chlorophyll
a
was
comparable
to
that
of
the
positive
control
(orlistat)
with
IC
50

of

20.53
±
1.97
µg/mL.

Chlorophyll
a
also
exhibited
potent
anti-obesity
activity
in
silico,
with
a
binding

affinity
of
-11.66
kcal/mol
to
5ZUN
protein.
However,
chlorophyll
a
did
not
meet
the
drug-likeness

criteria,
and
was
predicted
to
hepatotoxic
and
cardiotoxic.

Keywords:
Anti-obesity,
Chlorophyll
a,
Pancreatic
Lipase,
Spirulina.