3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P26 REDuCTION POwER, POLyPhENOLS
CONTENT AND ANTIMICRObIAL ACTIVITy
OF hONEy
KATARínA FATRCOVá-ŠRAMKOVáa , JAnKA
nôŽKOVáb , MAGDA MáRIáSSYOVác , MIROSLAVA
KAČánIOVád and eVA DUDRIKOVáe aDepartment of Human Nutrition, Slovak University of Agriculture
in Nitra (SUA), Tr. A. Hlinku 2, 949 76 Nitra,
bInstitute of Biodiversity Conservation and Biosafety, SUA
Nitra,
cFood Research Institute, Centre in Modra,
dDepartment of Microbiology, SUA Nitra,
eUniversity of Veterinary Medicine in Košice, Slovak Republic,
katarina.sramkova@uniag.sk
Introduction
Recent views propose honey not only as a health-promoting
dietary supplement, but shed light on its antioxidant
properties. Honey has been reported to have antifungal activity,
but not many species of fungi have been tested 1 . Superficial
fungal infections are amongst the most difficult diseases
to successfully treat, antibiotics which successfully combat
bacterial diseases being largely ineffective against fungi.
So a treatment which has both antifungal and antibacterial
activities would be most beneficial. Therefore the effectiveness
of honey against the dermatophyte species which
most frequently cause superficial mycoses (tineas such as
ringworm and athletes foot) was investigated 2 . The aim of
the study was to measure the reduction power, content of
polyphenols and antimicrobial activity of honey.
Materials and Methods
Two honey samples were obtained directly from beekeepers
during the 2007 harvest, from different locations across
Slovak Republic. The floral origin of the samples was specified
by microscopic analyses of pollen grains at Institute of
beekeeping in Liptovsky Hradok. Honeys were derived from
different plant species namely Castanea sativa Mill. and Brassica
napus subsp. napus L. Honey samples were stored at
4 °C in the dark until analysed.
Reduction power was evaluated by the method of Prietto
et al. 3 . This method is established on reduction of Mo (VI)
to Mo (V) with an effect of reduction parts in the presence
of phosphor under formation of green phosphomolybdenum
complex. Solution absorbance of reducing sample was
measured at 705 nm (UV-1601, Shimadzu, Tokyo, Japan)
toward black experiment (distilled water). Reduction power
of compounds (RP AA ) expressed as quantity of ascorbic acid
necessary to achieve the same effect in µg ml –1 was calculated
using the equation (1).
Total polyphenols content was quantified according to
the Folin-Ciocalteau spectrophotometric method using tanin
as reference standard 4 .
s628
RP AA = (A 705 nm – 0.0011)/0.00236 (1)
The potential antimicrobial activity of selected honey
samples against Alternaria infectoria, Scopulariopsis brevicaulis,
Trichophyton ajelloi and Saccharomyces cerevisiae
was studied using the agar well diffusion method. The strains
of fungi were maintained on Czapek-Dox agar (CDA, HiMedia).
Honey solutions were prepared in three fractions: 50, 25
and 10 % (by mass per volume). Experimental results were
expressed as means ± standard deviation. All tests were performed
in triplicate.
Results and Discussion
Reduction power of chestnut honey compounds
was higher (4,083.67 ± 4.50 µg ml –1 ) than of rape honey
(3,618.33 ± 3.30 µg ml –1 ). Comparison of polyphenols
content also refers on higher values in chestnut
honey than in rape honey (65.33 ± 3.86 mg kg –1 versus
41.00 ± 2.16 mg kg –1 ). The value of polyphenols for chestnut
honey was approximately 1.6-fold higher than that for rape
honey.
Bertoncelj et al. 5 reported that total phenolic content
(determined by the modified Folin-Ciocalteu method), antioxidant
activity and colour parameters differ widely among
7 different Slovenian honey types. In the case of chestnut
honey the phenol content was 199.9 ± 34.1 mg kg –1 , i.e. 3fold
more than in our present study. The results obtained from
the study by Beretta et al. 6 showed that the total phenol content
in chestnut honey was 211.2 mg kg –1 , i.e. 3.2-fold more
than in our present study.
Vela et al. 7 observed that the phenolic compounds are
partly responsible for the antioxidant effects of honey, but
obviously there are other factors involved.
Table I
Antimicrobial effect of honey samples
Honey concentration [%]
10 25 50
Castanea sativa Mill.
A. infectoria 11.46 ± 0.45 15.83 ± 0.99 18.21 ± 0.40
S. brevicaulis 11.70 ± 0.67 14.40 ± 0.99 18.75 ± 0.25
T. ajelloi 14.55 ± 1.12 18.11 ± 0.39 21.75 ± 0.35
S. cerevisiae 8.15 ± 0.18 10.32 ± 0.30 12.84 ± 0.93
Brassica napus subsp. napus L.
A. infectoria 10.94 ± 1.59 15.77 ± 0.12 17.22 ± 0.35
S. brevicaulis 9.93 ± 0.09 12.36 ± 0.44 17.37 ± 0.43
T. ajelloi 13.77s628 ± 1.01 17.38 ± 0.83 20.99 ± 0.52
S. cerevisiae 7.51 ± 0.47 11.83 ± 0.89 14.48 ± 0.86
Antifungal activities of the two honey samples with
different concentration against fungi Alternaria infectoria,
Scopulariopsis brevicaulis, Trichophyton ajelloi and Saccharomyces
cerevisiae strains are presented in Table I. The
obtained results characterize honey samples as a product with
a broad antimicrobial effect.