Research Article
Received: 12 December 2013 Revised: 30 April 2014 Accepted article published: 22 July 2014 Published online in Wiley Online Library:
(wileyonlinelibrary.com) DOI 10.1002/jsfa.6832
Chemical profile and antiacetylcholinesterase,
antityrosinase, antioxidant and -glucosidase
inhibitory activity of Cynometra cauliflora
L. leaves
Muhammad Abubakar Ado,
a
Faridah Abas,
a,b*
Intan Safinar Ismail,
a,c
Hasanah M Ghazali
b
and Khozirah Shaari
a,c
Abstract
BACKGROUND: The aim of the current study was (i) to evaluate the bioactive potential of the leaf methanolic extract of
Cynometra cauliflora L., along with its respective hexane, dichloromethane, ethyl acetate (EtOAc), n-butanol (n-BuOH) and
aqueous fractions, in inhibiting the enzymes -glucosidase, acetylcholinesterase (AChE) and tyrosinase as well as evaluating
their antioxidant activities. (ii) In addition, in view of the limited published information regarding the metabolite profile of C.
cauliflora, we further characterized the profiles of the EtOAc and n-BuOH fractions using liquid chromatography–diode array
detection–electrospray ionization–tandem mass spectrometry.
RESULTS: The leaf methanolic extract of C. cauliflora exhibited potent inhibition of all three enzymes and high antioxidant activ-
ity. The bioactivity was found to be concentrated in the EtOAc and n-BuOH fractions. A total of 18 compounds were identified in
these bioactive fractions, comprising a procyanidin trimer, procyanidin tetramer, procyanidin hexamer, taxifolin pentoside, cat-
echin, vitexin, isovitexin, kaempferol hexoside, quercetin pentoside, quercetin hexoside, apigenin-6-C-glucoside-8-C-glucoside,
kaempferol–coumaroyl hexoside and isorhamnetin hexoside.
CONCLUSION: The results indicated that C. cauliflora, the leaves in particular, is a rich source of bioactive compounds and could
be beneficial for further development of high-value phytomedicinal preparations and functional food products.
© 2014 Society of Chemical Industry
Keywords: Cynometra cauliflora; LC-DAD-ESIMS/MS; -glucosidase inhibition; antioxidant; antityrosinase; antiacetylcholinesterase
INTRODUCTION
Cynometra cauliflora, locally known as ’nam-nam’, is a small
branched perennial tree that is 3–5 m tall with flowers and fruits
on its rough, grey-brown and robust trunk. The plant belongs to
the family Fabaceae and is typically found in eastern and northern
Peninsular Malaysia, from which it has spread to Southeast Asia
and India.
1
A decoction of the leaves is traditionally used for
treating diabetes and hyperlipidemia.
2,3
The mature fruit can be
eaten raw or cooked with sugar to make a sweet compote, or fried
in batter. The fruits have also been reported to have useful medic-
inal properties and used as folk medicine. The fruits have been
used to cure loss of appetite, while the seed oil is used for curing
skin diseases.
4
Qualitative phytochemical analysis of the aqueous
extracts of the plant indicated the presence of saponins, tannins
and flavonoids in all plant parts. Terpenoids were found only in
the leaves and fruits, while cardiac glycosides were detected in
both mature and young leaves, in the bark but not in the stems.
2
It is now known that radical oxygen species (ROS), liberated
along with some other components in the body, are capable of
destroying cellular constituents and act as secondary messengers
for some chronic diseases, such as diabetes, Alzheimer’s disease
(AD), coronary heart diseases, skin disease and/or inflammation.
5
These ROS are chemical units consisting of an oxygen free radical,
such as hydroxyl radical (OH
•
), superoxide anion radicals (O
•-
2
),
nitric oxide (NO), peroxynitrite and also non-radical species, such
H
2
O
2
and singlet oxygen (
1
O
2
).
5
Since antioxidants can scavenge
ROS, they can be beneficial in the treatment of diseases.
6,7
In gen-
eral, the polyphenols of fruits and vegetables have been reported
to contain protective antioxidant components that are used as
potential candidates for treating many chronic diseases, such as
diabetes, AD, cardiovascular disease and cancer. This protective
effect is due to their properties as free radical scavengers, singlet
∗
Correspondence to: Faridah Abas, Laboratory of Natural Products, Institute
of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
E-mail: faridah_abas@upm.edu.my
a Laboratory of Natural Products, Institute of Bioscience, Universiti Putra
Malaysia, 43400 Serdang, Selangor, Malaysia
b Department of Food Science, Faculty of Food Science and Technology, Univer-
siti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
c Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400
Serdang, Selangor, Malaysia
J Sci Food Agric (2014) www.soci.org © 2014 Society of Chemical Industry