This study evaluated the α-glucosidase inhibitory activity of Pereskia bleo extracts. The leaves of P. bleo were extracted with methanol and partitioned into hexane, chloroform, and butanol extracts. An enzyme assay showed the chloroform extract demonstrated the strongest α-glucosidase inhibitory activity at 69.0% inhibition at a concentration of 0.5 mg/ml, comparable to the standard drug acarbose. The results indicate the methanol, chloroform and butanol extracts of P. bleo have potential as natural α-glucosidase inhibitors.

1. An Evaluation of Pereskia bleo Extracts
against α-Glucosidase Inhibition
Musthahimah M, Farahdina M, *Choo CY.
MedChem Herbal Research Group, Faculty of Pharmacy, Universiti Teknologi MARA,
42300 Puncak Alam, Selangor, Malaysia.
E-mail address: choo715@puncakalam.uitm.edu.my
Abstract
α -Glucosidase is an enzyme catalyzing the breakdown of carbohydrate into glucose in the small intestine.
Inhibition of α -glucosidase enzyme is considered one of the alternative treatment for diabetes by reducing
postprandial hyperglycemia. Thus, investigation of Pereskia bleo (P.bleo) as natural product medicine is vital
to control diabetic condition of patients. The aim of study is to detect α-glucosidase inhibitor of P.bleo
extracts. The ground dried leaves of P.bleo were extracted in methanol and the crude extract was sequentially
partitioned with n-hexane, chloroform and butanol. The inhibitory effects of the four extracts are studied
through kinetic cycle of enzyme inhibition comparing with standard drug, acarbose. The chloroform extract
from P.bleo demonstrated (69.0±0.1) percent α -glucosidase inhibition at a concentration of 0.5 mg/ml, which
showed the strongest inhibitory activity. The result indicated chemical constituents from the
methanol, chloroform and butanol extracts from P.bleo are potential for α -glucosidase inhibitor.
1.0 Introduction
The world’s population is burdened with diabetes disease
and the estimation from 2010 to 2030 show increase of
number of prevalence from 285 million to 439 million
(Shaw et al., 2010).
Pereskia bleo (Kunth) D.C. is a medicinal from the
cactaceae family and has been traditionally used by local
communities in Malaysia. This plant is known as ‘jarum
tujuh bilah’ or ‘seven star needle’ or ‘qi xing chen’ in
Malaysia. Present study is carried out to evaluate its α-
glucosidase inhibitory activities of P.bleo extracts.
3.0 Results and Discussion
The chloroform extract from P.bleo demonstrated
(69.0±0.1) % α -glucosidase inhibition at a concentration of
0.5 mg/ml, which showed the strongest inhibitory activity.
Fig 1 : α-Glucosidase inhibitory activity of P.bleo
extracts.
4.0 Conclusion
The result indicated chemical constituents from the
methanol, chloroform and butanol extracts from P.bleo
have potential for α -glucosidase inhibitors.
5.0 References
Pistia-Brueggeman, G., Hollingsworth, R.I., (2001.). A
preparation and screening strategy for glycosidase inhibitors.
Tetrahedron 57: 8773-8778.
Shaw J. E., Sicree R. A., and Zimmet P. Z. (2010). Global
Estimates of the Prevalence of Diabetes for 2010 and 2030.
Diabetes research and clinical Practices, 87: 4–14
2.1 Plant Material
Leaves of P.bleo were collected and authenticated.
2.2 Extaction
The ground dried leaves of P.bleo were extracted in
methanol and the crude extract was sequentially
partitioned with n-hexane, chloroform and butanol.The
extracts were dried under reduced pressure with rotary
evaporator.
2.3 α-Glucosidase Assay
α-Glucosidase activity was assayed according to the
reported method with a slight modification (Pistia-
Brueggeman and Hollingsworth,2001) The phosphate buffer
(30ul), test extracts (10ul) and α-glucosidase enzyme
solution (20ul) were pipetted and mixed in a 96 well
microtiter plate. The mixture was incubated for 15min at
37°C. After incubation, 4-nitrophenyl α-D-glucopyranoside
(NPG) substrate solution (10 ul) was added. The increment
of absorbance due to the hydrolysis of NPG by α-
glucosidase was measured at the wavelength of 405nm with
a microtiter plate reader (Beckman Colter
DTX880,Germany). Acarbose was used as a positive
control and averages of three replicates were calculated. .
The percentage inhibition was calculated from the equation:
Inhibition (%) = [1-(Asample / Acontrol) x 100]
0
20
40
60
80
100
120
Methanol Hexane Chloroform Butanol Acarbose
%Inhibition
P.bleo extracts
0.1 mg/ml
0.5 mg/ml
1 mg/ml