Extraction of pure lycopene from industrial tomato waste in water using the extractor Naviglio

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African Journal of Food Science Vol 2 (2) pp, 037-044, April, 2008
Available online http://www.academicjournals.org/ajfs
ISSN 1996-0794 ©2008 Academic Journal

Ful Length Research Paper

Extraction of pure lycopene from industrial tomato
waste in water using the extractor Naviglio®

Daniele Naviglio1*, Fabiana Pizzolongo1, Lydia Ferrara2, Biagio Naviglio3, Alejandro Aragòn4,
and Antonello Santini1

1Dipartimento di Scienza degli Alimenti, Università di Napoli Federico II, Via Università 100, 80055 Portici (Napoli), Italy.
2Dipartimento di Chimica Farmaceutica e Tossicologia, Università di Napoli Federico II, Via Montesano 49, 80131
Napoli, Italy.
3Stazione Sperimentale per l’Industria del e Pel i e del e Materie Concianti, Via Poggioreale 39, 80143 Napoli, Italy.
4Facultad de Ciencias Agrarias y Forestales, Universidad de La Plata, Cal e 60 y 119, 1900 - La Plata (Buenos Aires),

Accepted 25 March, 2008

In this paper an innovative process for the extraction of pure lycopene from tomato-waste in water that
uses the Extractor Naviglio® and water as solvent is presented. The use of water as extracting solvent
considerably reduces the cost of the entire process if compared with the commonly used solvent-based
procedure or with the newer supercritical extraction process of lycopene from tomato-waste. Exhausted
tomato-waste treated with water can be then easily dried at room temperature and further used, e.g. in
agriculture or as food ingredient in animal nutrition. Lycopene, not soluble in water, was recovered in a
quasi-crystalline solid form and purified by SPE (Solid Phase Extraction) using a small amount of
organic solvent. The all trans lycopene was obtained at a very high grade of purity, not less than 98%
(w/w), with an average recovery from tomato waste of 14% (w/w). The availability of high purity all trans
lycopene allowed us also to measure the molar absorption coefficient, unique for each molecule. An
alternative procedure for the HPLC analysis, that uses a phenyl-hexyl silicone stationary phase as
inverse phase and a linear gradient in water and acetonitrile, is also described.

Key words: Lycopene, Extractor Naviglio®, tomato-waste, HPLC-Diode array, solid-liquid extraction,
chromatography, solid phase extraction.


Lycopene, whose structural formula is reported in Figure
tance of lycopene rapidly increased due to its pharmaco-
1, is a fat soluble carotenoid with 11 conjugated double
logical and anti carcinogenic properties (Franceschi et al.,
bonds in the molecule, and it is a precursor of the ?-
1994; Giovannucci, 1999; Livny et al., 2002) and
carotene with a wel known antioxidant activity, reported
antioxidant activity (Di Mascio et al., 2002; Heber and Lu,
as at least twice that of the ?-carotene (Sies and Stahl,
2002; Sies and Stahl, 1998). Epidemiological studies
1998; Di Mascio et al., 2002). Lycopene can be easily
indicate a protective effects of lycopene against some
degraded by atmospheric oxygen and by light and
types of cancer, e.g., stomach and prostate cancer
converted from the al trans to the cis forms, that show a
(Stacewicz – Sapuntzakis and Bowen, 2005; Stahl and
decreased biologic activity (Lee and Chen, 2002 Wang
Sies, 1996), so the demand for this molecule and for the
and Chen, 2006.). For these reasons it must be stored at
carotenoids in general, is rapidly growing (Ulrich, 2000).
a very low temperature ( -70°C) away from the light and
In the literature, different synthetic pathways for this
from the atmospheric oxygen. In the last years the impor-
molecule have been reported, but in al cases the syn-

thesis of lycopene seems to be a very expensive and

economical y not convenient procedure (Zhuo-cai et al.,

2006). On the other hand, good amounts of lycopene are
*Corresponding author. E-mail: [email protected] Tel./fax: +39
contained in many natural products, like tomato
81 2539348.
(Lycopersicon esculentum Mil .), water-melon, red pep-

038 Afr. J. Food Sci.

products from tomato industry, the relevant interest for
this molecule and its biological activity, and starting from
the consideration that better methods for the charac-
terization and determination of lycopene are needed
(Roldán-Gutiérrez and Luque de Castro, 2007), the main
aim of this work is to propose a new method for the
extraction and characterization of lycopene from tomato
wastes. The extraction procedure was realized using the
Naviglio Extractor (Naviglio, 2003) that uses a new
solid-liquid extraction technology (Naviglio, 2000), and
tap water as extracting solvent fol owed by a simple and
rapid purification step, that requires a minimum quantity
of organic solvent.

Figure 1. Structural formula of lycopene.


per, papaya etc. (Britton, 1991) This molecule is also
Acetone, methanol, acetonitrile, chloroform, dichloromethane, n-
responsible for the red intense colour of these vege-
hexane (al solvents were of analytical grade from Fluka, Bucks,
tables, and a lycopene content in the range between
Switzerland); de-ionized water of HPLC grade was produced by
5.40-1500 mg/kg in tomato paste (wet weight) (Roldán-
means of Mil i-Q (Mil ipore); lycopene standard was purchased from
Gutiérrez and Luque de Castro, 2007) and between 20-
Sigma Aldrich; Extractor Naviglio® Mod. 500 cc (Nuova Estrazione
30 mg/kg in tomato peels as raw material (Rozzi et al.,
S.a.s., Naples, Italy); Spectrophotometer UV 1601 (Shimadzu
Corp., Tokyo, Japan); HPLC-Diode array, mod. 1100 (Agilent
2002) were determined, respectively.
Technologies, Santa Clara, CA, USA); Cartriges octadecyl Solid
It is worth noting that conventional methods for the
Phase Extraction (SPE-C18) 10 g (Restek Corp., Bel efonte, PA,
extraction of lycopene from natural vegetal origin sources
USA); filters 0.20 micron (Mil ipore, Bedford, MA, USA); Phenyl-
use great quantities of organic solvents and the extrac-
hexyl silicone HPLC column 250x4.6 mm, 5 micron particle size
tion procedure is usual y fol owed by a complex
(Phenomenex, Torrance, CA, USA).
purification step (Olives Barba et al., 2005 Sadler et al.,

1990.). In the case of lycopene recovery from the tomato-
Brief description of the Naviglio Extractor®
waste, the extraction can also be conducted using carbon

dioxide in supercritical state (Rozzi et al., 2002), and this
In this work the Naviglio Extractor® shown in Figure 2 and described
method al ows to recover a greater quantity of carote-
elsewhere (Naviglio, 2003) was used. This device is a rapid and
noids even if partly mixed in an oleoresin containing
dynamic solid-liquid extractor that applies the principle that in a
around 6% (w/w) in lycopene (Vági et al., 2007). This
suitable solvent, generating a negative pressure gradient and letting
it to go to equilibrium between outside and inside of a solid matrix,
method, unfortunately, is actual y quite expensive, mak-
that contains compounds that can be extracted in the solvent
ing the entire procedure economical y not suitable for a
fol owed by a rapid equilibrium condition restoring, a forced extrac-
large scale process. Biotechnological production of lyco-
tion of the not chemical y bound compounds contained in the solid
pene using micro-organisms (Sandmann, 1994), has
matrix is produced (Naviglio’s Principle). The Naviglio Extractor®
been proposed too, but always at the bench scale and, in
can operate at room temperature or at sub-ambient temperature,
most cases, with a weak specific yield, even if recently a
and it works applying a pressure increase on the surface of the
liquid phase containing the solid material (matrix) to be extracted.
new approach that can be scaled-up to an industrial
The use of low or room temperature greatly reduces the thermal
application has been proposed (Lopez-Nieto et al., 2004).
stress for any heat susceptible substances present in the matrix,
Since tomato by-products quantities deriving from
e.g. lycopene that can be degraded when using high temperature
industrial processes are growing annual y, e.g. in Europe
for the extraction (Lee and Chen, 2002).
it is evaluated that about ten mil ion tons of tomatoes are
The device used consists of one extracting chamber equipped
with a cylinder and a piston where, at the bottom, one porous set let
processed by the food industry, the deriving wastes can
the liquid phase and liquid soluble substances pass through, while
be quantified in approximately 0.1 mil ion tons, and
the solid particles are blocked. The solid raw material is put in the
represent an interesting low cost source of lycopene. Italy
chamber that is then fil ed with the solvent (organic, inorganic or a
is among the main producers of tomatoes in Europe and
mixture of solvents). Pressure gradient is applied al owing the
the by-products and the residues of the industrial pro-
system to reach equilibrium (Static phase) at a pressure of about 8
cessing of tomatoes that can be reincorporated in low
atm. When the piston is moved from its equilibrium position, the
dynamic phase starts; this step is performed for five times and for a
quality tomato products or used as an ingredient in
brief period of time with aim of remixing the solutions and to al ow
animal food, could be more efficiently used as a source of
the diffusion of the extracted compounds. The movement of the
pure lycopene. Considering both the availability of the by-
piston and hence the static and dynamic steps alternate til the

Naviglio et. al 039

Extraction by means of Extractor Naviglio®

Ten samples each constituted of 100 grams of tomato peels and
by-products from different farms in the Naples area, were placed in
a bag made of 50 µm filtering membrane and transferred into the
chamber of the Extractor Naviglio mod. 500 cc. where 500 mL of
tap water was added. Extraction parameters used are the fol owing:
the total extraction time was set to four hours for a total of 60
cycles. The dynamic phase used 5 cycles (Piston was idle for 12 s
in the up and down positions) and for the static phase a 2 min time
was used. After extraction the bag was removed and strongly
pressed in order to completely recover the water (About 450 mL).
The aqueous extract was loaded on octadecyl Solid Phase
Extraction (SPE-C18) 10 g column vacuum packed; column was
washed with methanol, that does not dissolve lycopene, in order to
remove pigments and then the minimum quantity of acetone was
used to recover lycopene. The acetone extract was analysed by
spectrophotometric and HPLC analysis to confirm the presence of
To verify if the use of tap water could affect the extraction, the
same extraction procedure was repeated using deionised water
(See Table 1).

Spectrophotometric analysis

Extracts were filtered through 0.20 micron membrane (Mil ipore,
Figure 2. Naviglio Extractor®, Mod. 500 cc. (Depurex88,
Bedford, MA, USA) and anhydrified on sodium sulphate anhydrous
Padua, Italy).
in order to eliminate water traces and rough impurities and

analysed by spectrophotometer in the 350-550 nm wavelength

range. The spectrophotometric analysis al owed to identify the al

trans lycopene molecule, by comparing the spectra of absorbance
extraction process was efficiently completed. One extraction cycle
and the absolute and relatives maxima peak of absorbance with
is formed by one static and one dynamic step; repeating more times
spectra of absorbance and maxima of absorbance exhibited by
these operations, complete exhausting of the solid matrix can be
lycopene standard and the relative values reported in literature.

When the maximum value set for the pressure is reached, the

device stops for 2 min, al owing the outside and inside part of the
HPLC analysis
solid matrix to equilibrate (Static phase) with the solvent pressure.

Immediately after this step, the piston moves, the air quickly leaves
In order to better verify the lycopene purity, filtered extracts were
the pneumatic chambers and the system causing a lowering of the
analysed by high-performance liquid chromatography (HPLC)
pressure inside the extraction chamber. This induces the starting of
system equipped with Diode array detector mod. 1100 (Agilent
the dynamic phase and at the beginning of this step the substances
Technologies, Waldbronn, Germany). A phenyl-hexyl silicon column
that are soluble in the used solvent and substances not chemical y
(250 x 4.6 mm I.D. 5 micron particle size) (Phenomenex, Torrance,
bonded to the matrix are extracted from the solid matrix and
CA, USA) was used for the separation. The flow rate was 1 ml/min
transferred to the solvent. Extractor Naviglio was recently employed
and the gradient water-acetonitrile was: time 0-3 min, acetonitrile
in the innovative production of lemon liquor (Naviglio et al., 2007).
0%; time, 20 min, acetonitrile 100%; hold for 5 min. Lycopene

standard was purchased from Sigma-Aldrich (Milan, Italy).

Chemical extraction of by-products of tomato

To compare the recovery of carotenoids in the starting material
Calibration curve
obtained using the Naviglio Extractor with those obtained with a

conventional chemical solvent based extraction procedure, chemi-
An amount of lycopene extract was dried under a nitrogen current.
cal extraction of lycopene from tomato by product was performed as
A stock solution of the extracted lycopene was prepared by
reported by others (Rozzi et al., 2002). A 2 g sample of tomato by-
dissolving 10.0 mg of lycopene in 100 ml of dichloromethane. From
products was placed in an extraction tube; 20 mL of chloroform
this standard solution by diluting 5 solutions containing from 1 to 5
were added and the tube was treated with ultra sounds for 30 min.
ppm were prepared. The same procedure was used to prepare the
The sample was then centrifuged for 15 min at 2000 rpm, and an
stock solution and the diluted solutions from the purchased stand-
aliquot was analysed by high-performance liquid chromatography
ard of lycopene. In this case 1.0 mg of lycopene was used.
(HPLC) to determine al trans lycopene. The extraction procedure
Correlation coefficient of calibration line was 0.998. In the same
was repeated to recover residual lycopene in the sample.
conditions a calibration line was prepared for the lycopene standard
Exhaustive extraction of tomato seeds and skins with additional
and in this case the correlation coefficient was 0.996 and angular
volumes of chloroform did not result in additional recovery of
coefficient was 5.8% lower than the previous one because its lower
purity. The observed linear response for lycopene was comprised in

040 Afr. J. Food Sci.

Table 1. Lycopene recovery from tomato by products using tap and demineralized water at different
values of the extraction time.

Lycopene content (mg/Kg)

Demineralized water Tap water
Tap water
Tap water
Tap water
(4 h)
(4 h)
(2 h)
(6 h)
(8 h)

Table 2. Recovered lycopene (A) and lycopene standard (B) maxima wavelenght of absorbance in four
different solvents and specific coefficient of absorption and molar extinction values.

?1 (nm)
? 2 (nm)
?3 (nm)
E1% (L/g.cm)
? (L/mol*cm)


?1 (nm)
? 2 (nm)
?3 (nm)
E1% (L/g.cm)
? (L/mol*cm)


the range 0-100 ppm.

Use of the Extractor Naviglio® for the recovery of
Determination of molar absorption and specific extinction
lycopene from tomato waste
coefficient of lycopene in different solvents

Four solutions of lycopene extracted with the Extractor Naviglio
The Naviglio Extractor was used to recover a solid
were prepared in n-hexane, chloroform, dichloromethane and
lycopene fraction in a para-crystal ine form from tomato-
acetone, at a concentration of 1.00 mg/l starting from the previously
waste in tap water, using the pressure and depressure
prepared stock solution (100 ppm). Table 2 reports the maximum
effect that operate in the solid-liquid extractor device. In
value for absorbance measured at a wavelength between 350-550
this case the extraction is al owed because of the effect
nm for each solution, the relative molar absorption coefficient and
of depression generated in the extractor and lycopene is
specific extinction coefficient.

Naviglio et. al. 041

Figure 3. Visible spectra of licopene in dichloromethane (1), acetone (2), n-hexane (3) and chloroform (4).

found in heterogeneous phase. For this reason during the
time period, recoveries did not increase and degradation
fol owing purification on SPE-C18, al -trans lycopene
events could occur, suggesting that 4 h is the optimum
present in the solid form, was separated on the filter
extraction time.
column, and a little fraction of the other pigments present

in the starting material were retained on the column head

of the octadecylsilicone stationary phase. Pigments were
Qualitative and quantitative analysis of lycopene
removed by washing with methanol, solvent in which

lycopene is total y not soluble, while washing with ace-
The elution of lycopene from the C18-SPE can be made
tone al owed the lycopene, very soluble in this solvent, to
directly using acetone or washing the column with metha-
be completely separated. Purity of extracted lycopene
nol first ad then eluting with acetone. In the first case, due
was checked by HPLC showing the presence of one
to the contemporary presence of other carotenoids like ?-
major peak corresponding to the al -trans lycopene, while
carotene and lutein, lycopene at not elevated purity grade
its quantification was possible through the calibration
was obtained while washing the column with methanol
first and al owed to obtain lycopene at a higher purity. At
Table 1 reports the recovery obtained for the lycopene
this point, it is worth noting that the washing of lycopene
using deionized and tap water, respectively. As it can be
is made after the extractive procedure and the quantity of
observed, there is no significant difference between the
solvent employed is minimal; however the great quantity
two liquids, suggesting that it is preferable to use tap
of by products are only touched with water and do not
water to keep low the cost of the entire industrial process.
come in contact with solvent. Lycopene purity was inves-
Optimum extraction time was 4 h and a recovery between
tigated byspectrophotometric UV-Vis and HPLC analysis,
1.5 and 3.9 mg/kg of lycopene was obtained; it can also
al owing to observe the presence of one peak corres-
be observed that continuing the extraction beyond this
ponding to the al trans pure lycopene. Figure 3 reports

042 Afr. J. Food Sci.

Figure 4. HPLC chromatograms of extracted lycopene at three different wavelengths, 413.4, 474.4, 506.4 (lower part),
and DAD acquisition between 200 and 600 nm of the peak measured at a retention time of 16.363 min. (upper part).

visible spectra of lycopene in dichloromethane, acetone,
Chemical extraction on the ten samples of raw mate-
n–hexane and chloroform respectively. The comparison
rials gave an average value of 20.3 mg/Kg. Table 1
of the maxima with those observed for the lycopene
reports recovery from tomato by products using tap water
standard shows an excel ent agreement (Tables 2a and
and demineralized water at different values of the extrac-
2b) and is consistent with data reported in the literature
tion time. At the optimum extraction time (4 h) the
(Davis, 1949; Roldàn-Gutiérrez and Luque de Castro,
recovery in tap water was comprised between 1.5 and
2007). Figure 4 reports HPLC results at three maxima
3.9 mg/Kg, corresponding to a percentage recovery of
wavelengths 413.4, 474.4 and 506.4 nm. One minor
7.5 and 19.5% (w/w), respectively, compared with
component, an impurity, was detected before the elution
chemical extraction. In demineralised water, the recovery
of lycopene peak and it was identified as beta-carotene.
ranged in the same conditions, from 1.7 and 3.9 mg/Kg,
The impurity did not exceed the 2% of total signal
corresponding to a recovery percentage of 8.5 and 19.5%
intensity, al owing us to conclude that lycopene is at least
(w/w), respectively. The possibility of using tap water as
of 98% purity (at ? = 474.4 nm). The DAD acquisition
extracting liquid notably reduces the costs of industrial
confirmed that no other contaminant was present in the
processes. The efficiency of the proposed process is
range of 200-600 nm. Chromatographic conditions report-
lower than the other procedures proposed in the litera-
ed in this paper are different from the ones used in
ture, because of minor quantity of lycopene present in
literature; in this case a phenyl-hexyl silicone as station-
para-crystal ine form in tomato waste. But when consi-
ary phase and a simple water-acetonitrile gradient were
dering the cost of the tomato waste and the easy
used and for this reason the method here reported could
dumping of the exhausted material, it turns to be cost
be proposed as a valid alternative to the ones reported in
reducing since no organic solvent is used in the extrac-
literature (Brumann and Grimme, 1981; Olives Barba et
tive phase, moreover a higher grade pure lycopene
al., 2005). This procedure al ows us to reduce times of
(>98% (w/w)) is achieved in the extraction using the
analysis in the case of a high purity lycopene containing
Extractor Naviglio to be compared with the chemical ex-
solutions for which it is not necessary the use of complex
traction procedure that al owed a 20-30 mg/Kg recovery
gradients of solvent for the elution.
at a 10-20 % (w/w) purity. Final y, the exhausted material

Naviglio et. al. 043

can be dried at room temperature and the weight reduces
existing procedures to extract lycopene from vegetal
about 95% (w/w). In this way it can be employed as cattle
sources that use organic solvents present some disad-
feed or as a manure in agriculture.
vantages: (i) organic solvents are general y toxic, so they

have to be completely removed from exhausted material

making necessary to use a complex purification step
Determination of molar absorption coefficient and
before dumping it; (i ) exhausted matrixes must be
relative specific coefficient of absorption
dumped as a special residue after extraction and they

cannot be re-used; (i i) organic solvents are not specific
The possibility of isolating pure lycopene from tomato
for lycopene, but at the same time other pigments or
wastes gave us the possibility to measure the molar
hydrophobic compounds (e.g. carotenes, xanthophyl s,
absorption coefficient (?) and the relative specific coeffi-
fat, etc.) present in the starting material are simulta-
cient of absorption (E1%) in some of the most commonly
neously extracted. Moreover, the purification of lycopene
used solvents, namely dichloromethane, acetone, n-
is obtained using HPLC on inverse phase, the most used
hexane and chloroform. Table 2 reports the obtained
technique, is particularly difficult and time consuming,
values for ? and E1%. In the literature different values of ?
since long time gradient and ternary or quaternary
and E1% for lycopene (Davis, 1949; Davis et al., 2003;
solvent gradients must be used (Brumann and Grimme,
Roldàn-Gutiérrez and Luque de Castro, 2007) are
1981) due to the co-presence of unwanted compounds in
reported, and the difficulty of obtaining accurate values
the organic extract. Final y, the high purity of the
principal y derives from the lack of a technique to obtain-
lycopene obtained with use of the extractor Naviglio
ing al -trans licopene at high purity. Moreover spectrum of
makes the industrial process very appealing. The pure
absorbance and molar absorption coefficient, unique for
al -trans lycopene extracted makes it possible to use it, at
each molecule, al ows the unique identification of the
a known dosage, as a drug and not only as a food
lycopene and can be used to confirm the presence of al -
trans lycopene. The high value of the measured molar

absorption coefficient can be correlated to the high

number of double bonds and the high conjugation of
double bonds present in the lycopene molecule, that is

Britton G (1991). Carotenoids: In Methods in plant biochemistry.
one of the compounds with the highest molar absorption
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Brumann T, Grimme LH. (1981). Reversed phase high performance

liquid chromatography of chlorophyl s and carotenoids. Biochem.

Biophys. Acta. 637: 8-17.
Davis AR, Fish WW, Perkins-Veazie P (2003). A rapid spectro-
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tomato products. Postharvest Biol. Technol., 28: 425-430.
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be easily scaled-up to become an industrial application
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Di Mascio P, Kaiser SP, Sies H (2002). Lycopene as the most efficient
for the production of very high grade of purity (?98%) al -
biological carotenoid singlet oxigen quencher. Arch. Biochem.
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compared with the cost of a conventional solvent or
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supercritical fluid phase extraction procedure, and since
(2002). Lycopene inhibits proliferation and enhances gap-junction
no special by-product to be wasted are produced, the
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overal process appears to be economical y convenient.
The material obtained after the extraction of the lycopene
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