INTRODUCTION
Ber (Zizyphus mauritiana Lamk.) grows excellently

in arid and semi-arid regions of the world and is considered
the poor man’s apple, being an excellent source of several
polyphenols including caffeic acid, p-hydroxybenzoic acid,
ferulic acid and p-coumaric acid (Dahiru and Obidoa, 2008).
As phenolics are known for their wide ranging health-
protecting properties as anti-atherogenic, anti-inflammatory
and anti-microbial, commercial processing of ber into juice
rich in phenolics could prove useful. However, extraction
of juice from ber is difficult and protracted because of its
pulpy nature and high pectin content. Enzyme-assisted
processing using pectinolytic enzyme is an effective
approach for degrading pectineous material to yield free-
flowing juice. In addition, the enzyme-catalyzed degradation
also helps release phenolics and flavonoids that would
otherwise be lost in press residues (Sowbhagya and Chitra,
2010). Several researchers have reported pectinase and
cellulase enzyme treatments to significantly enhance
recovery of phenolics and to improve functional properties
of the juice. In view of the enormous potential of ber as a
source of phenolics, the current study was undertaken to
examine the effect of enzyme-assisted processing on
nutraceutical composition of ber juice.

J. Hortl. Sci.
Vol. 10(1):54-56, 2015

Nutraceutical composition of ber (Zizyphus mauritiana Lamk.) juice: effect of
enzyme-assisted processing

V.S. Khandare, D.P. Waskar, B.M. Kalalbandi and T.J. Pawar
Department of Horticulture

Vasantrao Naik Marathwada Krishi Vidyapeeth
Parbhani – 431 402, India

E-mail: khandarevs@rediffmail.com

ABSTRACT
An investigation was undertaken to study the effect of pre-press maceration treatment with cell-wall degrading

enzyme, pectinase, on antioxidant composition of ber juice, during 2011-2012. Enzyme-assisted processing significantly
(p<0.05) improved antioxidant composition of ber juice. Ber juice extracted using pectinase had richer nutraceutical
composition than in the Control. There was an overall increase of 43% in juice yield, 30% in total phenolics and
37% in total flavonoids with use of pectinase. In vitro total antioxidant activity (AOX) in ber juice was 19.58μmol
Trolox/ml in Ferric Reducing Antioxidant Power (FRAP) and 13.44μmol Trolox/ml in Cupric Reducing Antioxidant
Capacity (CUPRAC) assay. There was 41-65% increase in total AOX of ber juice extracted with the enzyme over-
straight pressed juice. Results indicated that tailoring of the enzyme can yield antioxidant-rich juice products.

Key words: Ber, enzyme assisted processing, pectinase and antioxidant activity

MATERIAL AND METHODS
The present study was carried out on antioxidant

composition of ber juice as affected by enzyme-assisted
processing, during the year 2010-2011. Mature, ripe fruits
of ber (cv. Umran), free from blemishes and mechanical
injury were obtained from the local market of Parbhani and
processed at Post Harvest Technology Laboratory of
Department of Horticulture, Vasantrao Naik Marathwada
Krishi Vidyapeeth, Parbhani. Fruits were washed thoroughly
in tap water to remove any adhering dirt or dust. Whole
fruits were then subjected to hot-breaking at 90oC for 20
min to soften them. These were then macerated in a Waring
blender and, subsequently, passed through a laboratory-scale
pulper for extracting a homogeneous pulp and to separate
seeds. Pulp samples were weighed out into 500ml glass
bottles and the enzyme preparation (pectinase EC 3.2.1.1
from Aspergillus niger, 1 U/mg from Aspergillus sp.) was
added at four levels of dose: 0.10, 0.15, 0.20 and 0.25% E/
S. Control (straight-pressed) juice samples were incubated
without the enzyme under the same conditions. For each
concentration, 500ml pulp was taken in three replicates. The
bottles were capped and incubated at 50 oC in a
thermostatically controlled water bath for 1 h. The macerate
was then pressed using a hydraulic press with a nylon filter



55

Nutraceutical composition of ber juice

bag to extract the juice. Juice yield was determined by
weighing the juice extracted, which was subsequently heat-
processed at 90oC for 1min, and packed in clean, sterilized
glass bottles, upturned and sealed. This juice was then used
for analysis.

Determination of total amount of phenolics, flavonoids
and total antioxidant activity

Total phenolic content of the juice (80% ethanol
extract) was estimated spectrophotometrically using Folin–
Ciocalteu reagent, as per Singleton et al (1999). Results
were expressed as mg gallic acid equivalents (GAE/100ml).
Total amount of flavonoids was estimated by the method of
Zhishen et al (1999) and the results were expressed as
catechin equivalents/100 ml. Antioxidant activity was
measured using two in vitro assays: ferric-reducing
antioxidant power (FRAP), and cupric-reducing antioxidant
capacity (CUPRAC). FRAP assay was performed as per
Benzie and Strain (1996), and CUPRAC assay was
performed as per Apak et al (2004). Results were expressed
in mmol Trolox/ml (TE/ml).

Statistical analysis

Each experimental unit was replicated three times.
Data were subjected to Analysis of Variance, using
Completely Randomized Design.

RESULTS AND DISCUSSION
Juice yield

Data on effect of pectinase enzymes at different
doses (0.1–0.25%) on ber juice yield is presented in Fig. 1.
The pulpy macerate of ber was highly viscous and difficult
to press. With conventional straight-pressing (Control), the
yield averaged 27%, while, with increasing concentrations
of pectinase enzyme, juice-yield increased to 70%. Enzyme-
assisted processing accelerated liquefaction of the pulpy
macerate, resulting in an 43% increase in juice yield.

Total amount of phenolics, flavonoids and antioxidant
(AOX) composition of ber juice

Enzyme-assisted processing had a significant impact
on recovery of total phenolics and flavonoids too in ber juice.
Compared to the Control, percentage increase in recovery
of total phenolics was higher in pectinase treatments. Total
phenolics content increased to 314.36mg GAE/100ml at
0.25% pectinase, from an initial 240.48mg GAE/100ml
(Fig. 2). Phenolics contained in the vegetable and fruit matrix
appear to be entangled with the plant cell wall
polysaccharides via tight hydrophilic and hydrophobic bonds.
The release of those phenolics can be enhanced via enzyme

catalyzed degradation of the cell wall polysaccharides.
Enzyme facilitated polysaccharide helps in exposing possible
cell wall sites for phenolics, resulting in enhanced recovery
(Pinelo and Meyer, 2008).

Fig 1. Effect of pectinase treatment on juice yield in ber cv. Umran

Fig 2.  Effect of pectinase treatment on total phenol content in ber
juice cv. Umran

Fig 3.  Effect of pectinase treatment on total flavonids in juice of
ber cv. Umran

J. Hortl. Sci.
Vol. 10(1):54-56, 2015



56

Total flavonoids content in juice also showed
progressive increase with various pectinase treatments
(Fig. 3). Antioxidant activity of ber juice, too, improved
dramatically upon enzyme-assisted processing. Values for
this ranged from 14.47 to 19.82mmol/ml, respectively, in the
Control and in the juice treated with the enzyme pectinase
(Fig. 4). Overall, there was a significant increase in total
AOX in the juice over Control. An almost identical trend
was observed in CUPRAC assay (Fig. 4). High AOX in
enzyme-assisted juice may be attributed to a high recovery
of phenolic compounds observed in the juice. Similar results
on high phenolic content and antioxidant activity have been
reported in bilberry by previous workers (Puupponen-Pimia
et al, 2008).

Enzyme-assisted processing of ber significantly
enhanced nutraceutical composition of the juice, in contrast
to straight-pressing. These results could lead to tailoring of
the enzyme for obtaining optimum levels of antioxidants in
the juice products. The study also indicated that ber, a fruit

Fig 4.  Effect of pectinase treatment on antioxidant activity in
juice of ber cv. Umran

rich in nutrceuticals, can be commercially processed into
juice rich in phenolics.

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(MS Received 07 March 2014, Revised 29 April 2015, Accepted 20 May 2015)

Khandare et al

J. Hortl. Sci.
Vol. 10(1):54-56, 2015