Pharmacology & Pharmacy, 2013, 4, 696-700
Published Online December 2013 (http://www.scirp.org/journal/pp)
http://dx.doi.org/10.4236/pp.2013.49097
Open Access PP
In Vitro Preliminary Evidences on the Antioxidant
Properties of Biogenic Amines
Roberto Stevanato*, Mariangela Bertelle, Sabrina Fabris
Department of Molecular Sciences and Nanosystems, University Ca’ Foscari of Venice, Venice, Italy.
Received October 5th, 2013; revised November 18th, 2013; accepted November 29th, 2013
Copyright © 2013 Roberto Stevanato et al. This is an open access article distributed under the Creative Commons Attribution Li-
cense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
Antioxidant properties of the principal biogenic amines were determined in vitro by four analytical methods—Folin
Ciocalteu, DPPH, enzymatic and inhibition of lipid peroxidation—in order to avoid possible measuring-method linked
mistakes. Different results are obtained, depending on the parameters that each of them measures. The combination of
the data indicates that all examined amines show antioxidant characteristics: in particular, tyramine, serotonin, L-norepi-
nephrine, (-)-epinephrine and dopamine owing to their (poly)phenolic structure too, while aliphatic polyamines-sper-
mine, spermidine, putrescine and cadaverine-histamine, melatonin and tryptamine appear to act specifically on the
oxygen-consuming species involved in the lipid peroxidation of polyunsaturated fatty acids.
Keywords: Biogenic Amines; Antioxidants; Lipid Peroxidation; DNA Protection; Membrane Protection
1. Introduction
Biogenic amines constitute a large group of naturally
occurring and biologically active compounds containing
one or more amino groups, produced by decarboxylation
of amino acids.
Biogenic amine can be split into two physiologically
distinct groups:
1) Monoamines, containing one amino group, some-
time derivatized, connected to an aromatic ring by a two-
carbon chain, which acts as neuromodulators or neuro-
transmitters [1]; their reduced level appears to be the
cause of neurodegenerative diseases [2];
2) Polyamines, characterized by two or more amino
groups placed in a linear aliphatic chain, involved in
physiological processes such as cell growth and differen-
tiation [3]; their polycationic nature at neutral pH in-
duces electrostatic interactions with negative charges on
nucleic acids and phospholipids, stabilizing the structure
of chromosome s and membranes [4-6].
Some papers have been reported on the possible anti-
oxidant role of singular biogenic amines, while no sys-
tematic investigation on their antioxidant properties in
vitro or in vivo has been published.
Catecholamines and their metabolites appear to play a
key role in the redox balance for the formation of new
synapses and the removal of old ones [7], while mela-
tonin and its metabolites are involved in the reduction of
oxidative stress (antioxidant cascade of melatonin) [8].
Between polyamines, it has been found that spermine
acts as free radicals scavenger in nucleous, mitochondria
and brain [9-11] and a radical scavenging activity on
lipoperoxidation in vivo [12] or on methylmethacrylate
polymerization [13] by spermine and spermidine was
tested.
In order to contribute to individuating a possible role
of biogenic amines on the protection against ROS (reac-
tive oxygen species) injury, we studied in vitro the anti-
oxidant properties of twelve of these compounds by ap-
plying four different assays, to avoid possible measur-
ing-method linked mistakes. Besides, cyclic voltammetry
measurements, to verify the ability of biogenic amines to
easily give electrons to oxidant species, were also carried
out.
2. Materials and Methods
2.1. Chemicals
All chemicals, of the highest available quality, were ob-
tained from Sigma Chemical Co. (St. Louis, USA); ABIP
(2,2’-azobis[2’-(2-imidazolin-2-yl)propane] dihydrochlo-
*Corresponding author.

In Vitro Preliminary Evidences on the Antioxidant Properties of Biogenic Amines 697
ride) was obtained form Wako Chemicals (Germany).
The aqueous so lutions were prepared with quality milliQ
water. Each experiment was in triplicate.
2.2. Experimental Procedures
The ability of amines to prevent linoleic acid (LA) per-
oxidation was studied in sodium dodecyl sulfate (SDS)
micelles. As previously reported [14], the amines anti-
oxidant capacity was calculated as the concentration that
halves the rate of oxygen consumption due to the per-
oxidation process and it is expressed as inhibitory con-
centration (IC50).
2,2-Diphenyl -1-picrylhydrazyl (DPPH) radical scav-
enging ability assay is based on the capacity of an anti-
oxidant to scavenge the stable free radical DPPH [15,16]
and the results are expressed as catechin equivalent (CE).
Whole reducing capacity by Folin Ciocalteu assay and
Total Phenolics Content (TPC) determination by enzy-
matic method were carried out spectrophotometrically,
according to the procedure previously quoted [16] and
the results are expressed as catechin equivalent (CE).
Spectrophotometric measurements were recorded on a
UV-VIS Shimadzu UV-1800 instrument equipped with a
temperature controlled quartz cell. The measures of oxy-
gen consumption were carried out by an oxygen Micro-
electrodes MI-730 microelectrode connected to a poten-
tiostat Amel 559.
Cyclic voltammetry measurements were carried out in
a solution containing 1 mM amine in 50 mM sodium
phosphate, pH 7.4, and 50 mM potassium chloride.
A potentiostat μAutolab type III equipped with three
electrodes (vitreous graphite as working electrode, plati-
num as counterelectrode and SCE as reference electrode)
was used and the data collected by GPES Autolab soft-
ware.
3. Results
The histograms of Figure 1 show the results, expressed
as catechin equivalent, obtained applying Folin, DPPH
and enzymatic method to the examined biogenic amines.
It appears that spermine, spermidine, putrescine, ca-
daverine, i.e. linear aliphatic polyamines, do not show
reducing activity or electron scavenging ability; further-
more no response to the enzymatic assay was found, be-
cause lacking of phenolic structure.
On the contrary, tyramine, serotonin, norepinephrine,
epinephrine and dopamine, all containing phenolic func-
tional groups, give significative results for all three as-
says, with the exception of tyramine for which negative
appears the DPPH assay. This is not surprising on the
light of above reported considerations. Another exception
is the positive response of tryptamine to the Folin test. In
fact, from the chemical point of view, this last molecule
appears very similar to histamine that gives negative re-
sult.
Data obtained measuring the inhibition of lipid per-
oxidation appear sensitively different. In fact, Figure 2
shows high inhibition values also when aliphatic poly-
amines were used, as well as histamine, tryptamine and
melatonin show. It is interesting to observe the almost
Figure 1. Histograms, expressed as catechin equivalent, of the results obtained applying; DPPH, □ Folin and Enzy-
matic method to the examined polyamines.
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In Vitro Preliminary Evidences on the Antioxidant Properties of Biogenic Amines 698
Figure 2. Inhibition of oxygen consumption (%) due to the peroxidation process at 2 M concentration of biogenic amines.
equal value of aliphatic po lyamines, wh ich ranges around
43%.
High inhibition values, more than 50% and until 85%
were obtained for other phenol based biogenic amines, as
expected.
The results obtained by this last method, even if it is
more laborious and time consuming, appear more reli-
able, because the assay, more than others, mimes the
efficacy of an antioxidant compound to prevent oxidative
damage on lipoproteins or cell membrane by ROS injury
[17].
The experimental data here obtained confirm this as-
sumption and demonstrate that usual methods (Folin,
DPPH quenching, etc.), generally adopted to investigate
antioxidant properties of molecules, are not reliable for
their chemical and mechanicistic limits with respect to
the complexity of whole reactions involved in the ROS
injury.
In fact, aliphatic polyamines, besides histamine and
tryptamine, show high inhibition (ranging from about 40
to 60%) of lipid peroxidation at very low concentrations
(2 µM), but give negative responses to other assays here
used. This means that these amines are not susceptible by
Folin reagent oxidation, electron transfer from DPPH
radical, and not involved in the enzymatic reaction be-
cause lacking of phenolic structure essential for the en-
zymatic coupling reaction [16]. Moreover, triazolopyri-
dines derivatives, which do not contain (poly)phenolic
groups but primary and tertiary amino groups, similarly
to the examined biogenic amines, appear to acts directly
and indirectly as an efficient ROS scavenging in vivo, as
found by measuring the concentration of malondialde-
hyde by paraquat-induced lipid peroxidation [18].
To verify the ability of biogenic amines to easily give
electrons to oxidant species, cyclic voltammetry meas-
urements were carried out. The data of Table 1 show that
polyamines spermine, spermidine, cadaverine e putre-
scine are characterized by a very high discharge potential
(1 V), while lower values (ranging from 0.196 V of
dopamine to 0.805 V of tryptamine) were recorded for all
others amines.
All these results indicate that aliphatic polyamines,
histamine, tryptamine and, to some extent, melatonin,
can inhibit lipid perox idation only interacting directly via
chemical mechanism with oxygen consuming species,
that is towards ROS or ROS-induced species of the same
type and structure of those forming in the lipid peroxide-
tion of membranes. Hydroxyl radicals, reactive species
for which efficient scavenging properties for these
amines were found [9-10,12], can not be invoked in this
case because these radicals apparently are not directly
formed in the lipid peroxidation mechanism. Moreover,
indications about the scavenging activity of polyamines
towards alkyl or peroxy radicals derived from polyun-
saturated fatty acids were suggested by indirect meas-
urements [13].
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In Vitro Preliminary Evidences on the Antioxidant Properties of Biogenic Amines 699
Table 1. Discharge potential vs SCE of biogenic amines. A
vitrous graphite as working electrode was used.
Amine E(V)
spermine 1
spermidine 1
putrescine 1
cadaverine 1
histamine 0.765 ± 0.001
tryptamine 0.805 ± 0.003
melatonin 0.680 ± 0.001
serotonin 0.430 ± 0.005
tyramine 0.692 ± 0.006
dopamine 0.196 ± 0.008
L-norepinephrine 0.302 ± 0.007
(-)-epinephrine 0.311 ± 0.007
4. Discussion
As previously reported [14], no analytical method can
give a reliable measure of the antioxidant efficacy of a
molecule, because of the different parameters that each
assay measures and the manifold types of reactions in-
volved in the ROS damage. In fact, biogenic amines
show very different chemical structures and can be as-
sembled into three groups.
Besides primary amine group, they are characterized
respectively: 1) by aliphatic chain spaced or ended by
other secondary or primary amine groups respectively
(spermine, spermidine, putrescine, cadaverine); 2) by a
terminal imidazole (histamine) and indole group (tryp-
tamine, melatonin and serotonin); 3) by phenolic (tyra-
mine and serotonin again) or polyphenolic (L-norepine-
phrine, (-)-epinephrine, dopamine) function.
For this reasons in this work, multip le tests, represent-
ing various redox mechanisms, have been used as the
best strategy for stating an empirical and approximate
scale of effectiveness. In fact, the well-known Folin-
Ciocalteu assay is a general measure of antioxidant’s
reducing capacity and it is largely a specific because
correlated only to the redox potential of the chemical
species involved; DPPH based method measures the
ability of a molecule to scavenge the stable free radical
DPPH, but this last compound may be inert to many an-
tioxidant and the reaction could not go to completion, as
found for some phenolic derivatives [19]; enzymatic
method, we proposed, determines phenolic structures
owing to peroxidise specificity [16]. In this paper, in ad-
dition to these analytical methods, the measures of the
inhibitory capacity of ABIP-induced lipid peroxidation
and of the electrochemical ability to give electrons to
oxidative species are also carried out.
The experimental data indicate that all examined bio-
genic amines show antioxidant properties; in particular,
tyramine, serotonin, L-norepinephrine, (-)-epin ephrine and
dopamine for their (poly)phenolic structure too, while
aliphatic polyamines, histamine, tryptamine and mela-
tonin appear to act specifically on the oxygen con-
suming species involved in the lipid peroxidation of
polyunsaturated fatty acids in biological systems.
Considering that spermine is coupled by electrostatic
bonds to phosphate groups of nucleic acids and mem-
brane phospholip ids, stabilizing helical and bilayer struc-
tures, these results suggest that spermine and probably
other polyamines also could carry out a protective ac-
tion of nucleotide bases and acyl chains of phospholipids
against ROS injuries. Moreover, it is necessary to take
into consideration that polyamines oxidation, consequent
their protective action, decreases their stabilizing role
towards the above reported structures.
Furthermore, catecholamines, owing to effective cate-
chol group which can oxidatively convert to the corre-
sponding o-quinones, can perform a protective function
towards synaptic vesicles and, in particular, their phos-
pholipid moiety from ROS induced peroxidation, but
their loss contribute to neurodegenerative disorder, nota-
bly Parkinson’s disease [2]. Moreover, quinone structure
can easily react with primary amine groups of biogenic
amines or proteins to form Schiff base.
Further investigations to explain a possible chemical
mechanism justifying the antioxidant properties of bio-
genic amines are in progress.
REFERENCES
[1] S. H. Snyder, “Drug and Neurotransmitter Receptors in
the Brain,” Science, Vol. 224, No. 4644, 1984, pp. 22-31.
http://dx.doi.org/10.1126/science.6322304
[2] S. Surendran and S. Rajasankar, “Parkinson’s Disease:
Oxidative Stress and Therapeutic Approaches,” Neuro-
logical Sciences, Vol. 31, No. 5, 2010, pp. 531-540.
http://dx.doi.org/10.1007/s10072-010-0245-1
[3] C. Tabor and H. Tabor, “Polyamines,” Annual Review of
Biochemistry, Vol. 53, 1984, pp. 749-790.
http://dx.doi.org/10.1146/annurev.bi.53.070184.003533
[4] R. Kaur-Sawhney, A. Altman and W. Galston, “Dual
Mechanisms in Polyamine-Mediated Control of Ribonu-
clease Acti vity in Oat Lea f Protopla sts, ” Plant Physiology,
Vol. 2, 1978, pp. 158-160.
http://dx.doi.org/10.1104/pp.62.1.158
[5] R. Stevanato, A. Wisniewska and F. Momo, “Interaction
of Spermine with Dimyristoyl-L-alpha-phosphatidyl-DL-
glycerol Multilamellar Liposomes,” Archives of Biochem-
istry and Biophysics, Vol. 346, No. 2, 1997, pp. 203-207.
http://dx.doi.org/10.1006/abbi.1997.0253
[6] F. Momo, S. Fabris and R. Stevanato, “Interaction of
Open Access PP

In Vitro Preliminary Evidences on the Antioxidant Properties of Biogenic Amines
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700
Linear Mono- and Diamines with Dimyristoylphosphati-
dylcholine and Dimyristoylphosphatidylglycerol Multi-
lamellar Liposomes,” Archives of Biochemistry and Bio-
physics, Vol. 382, No. 2, 2000, pp. 224-231.
http://dx.doi.org/10.1006/abbi.2000.2014
[7] J. Smythies, “Redox Aspects of Signalling by Catecola-
mines and Their Metabolites,” Antioxidants & Redox
Signalings, Vol. 2, No. 3, 2000, pp. 575-583.
http://dx.doi.org/10.1089/15230860050192332
[8] A. Galano, D. X. Tan and R. J. Reiter, “Melatonin as a
Natural Ally against Oxidative Stress: A Physicochemical
Examination,” Journal of Pineal Research, Vol. 51, No. 1,
2011, pp. 1-16.
http://dx.doi.org/10.1111/j.1600-079X.2011.00916.x
[9] H. C. Ha, N. S. Sirisoma, P. Kuppusamy, J. L. Zweier, P.
M. Woster and R. A. Casero, “The Natural Polyamine
Spermine Functions Directly as a Free Radical Scaven-
ger,” Proceedings of the National Academy of Sciences
USA, Vol. 95, No. 19, 1998, pp. 11140-11145.
http://dx.doi.org/10.1073/pnas.95.19.11140
[10] I. G. Sava, V. Battaglia, C. A. Rossi, M. Salvi and A.
Toninello, “Free Radical Scavenging Action of the Natu-
ral Polyamine Spermine in Rat Liver Mitochondria,” Free
Radicals Biology & Medicine, Vol. 41, No. 8, 2006, pp.
1272-1281.
http://dx.doi.org/10.1016/j.freeradbiomed.2006.07.008
[11] N. A. Velloso Bellé, G. Dalmolin, G. Fonini, M. A. Rubin
and J. B. Teixeira Rocha, “Polyamines Reduces Lipid
Peroxidation Induced by Different Pro-Oxidant Agents,”
Brain Research, Vol. 1008, No. 2, 2004, pp. 245-251.
http://dx.doi.org/10.1016/j.brainres.2004.02.036
[12] S. M. Hernandez, M. S. Sanchez and M. N. Schwarcz de
Tarlovsky, “Polyamines as a Defense Mechanism against
Lipoperoxidation in Trypanosoma Cruzi,” Acta Tropica,
Vol. 98, No. 1, 2006, pp. 94-102.
http://dx.doi.org/10.1016/j.actatropica.2006.02.005
[13] S. Fujisawa and Y. Kadoma, “Kinetic Evaluation of
Polyamines as Radical Scavengers,” Anticancer Research,
Vol. 25, No. 2A, 2005, pp. 965-970.
[14] S. Fabris, F. Momo, G. Ravagnan and R. Stevanato, “An-
tioxidant Properties of Resveratrol and Piceid on Lipid
Peroxidation in Micelles and Monolamellar Liposomes,”
Biophysical Chemistry, Vol. 135, No. 1-3, 2008, pp. 76-
83. http://dx.doi.org/10.1016/j.bpc.2008.03.005
[15] M. S. Blois, “Antioxidant Determination by the Use of a
Stable Free Radical,” Nature, Vol. 181, No. 4617, 1958,
pp. 1199-1200. http://dx.doi.org/10.1038/1811199a0
[16] R. Stevanato, S. Fabris and F. Momo, “New Enzymatic
Method for the Determination of Total Phenolic Content
in Tea and Wine,” Journal of Agricolture and Food
Chemistry, Vol. 52, 2004, 6287-6293.
http://dx.doi.org/10.1021/jf049898s
[17] E. Gregoris and R. Stevanato, “Correlations between
Polyphenolic Composition and Antioxidant Activity of
Venetian Propolis,” Food and Chemical Toxicology, Vol.
48, No. 1, 2010, pp. 76-82.
http://dx.doi.org/10.1016/j.fct.2009.09.018
[18] R. A. Mekheimer, A. A. Radwan Sayed and E. A. Ahmed,
“Nobel 1,2,4-Triazolo[1,5-
 ]pyridines and Their Fused
Ring Systems Attenuate Oxidative Stress and Prolong
Lifespan o f Caenorhabiditis Ele gans,” Journal of Medicinal
Chemistry, Vol. 55, 2012, pp. 4169-4177.
http://dx.doi.org/10.1021/jm2014315
[19] R. Stevanato, S. Fabris, M. Bertelle, E. Gregoris and F.
Momo, “Phenolic Content and Antioxidant Properties of
Fermenting Musts and Fruit and Vegetable Fresh Juices,”
Acta Alimentaria, Vol. 38, No. 2, 2009, pp. 93-203.
http://dx.doi.org/10.1556/AAlim.2008.0031