Conference PaperPDF Available

GREEN SYNTHESIS OF SILVER NANOPARTICLES FROM HYPERPIGMENTED TOMATO SKINS AND PRELIMINARY EVALUATION OF THE INSECTICIDAL ACTIVITY

Authors:
  • CREA - Concil for Agricultural Research and Economics

Abstract

With a view to sustainable production and circular economy, the recovery of biomass otherwise destined for disposal will be a strategic objective in the near future. Yearly, the tomato industry produces hundreds of thousands of tons of waste, which could be usefully applied in various sectors. This work proposes the use of the skins of a hyperpigmented (black-skinned) tomato line for the stabilization of silver nanoparticles. Aqueous extracts produced from this residue have proven to be suitable for producing silver nanoparticles with an average diameter of 22 4 nm. Subsequently AgNPs were tested for in vitro cowpea weevil (Callosobruchus maculatus) control. At a concentration of 20% they proved capable of inducing 52% mortality on adults of the insect. To our knowledge, this is the first case where the tomato peels were used to synthesize Ag-nanoparticles.
GREEN SYNTHESIS OF SILVER NANOPARTICLES FROM HYPERPIGMENTED TOMATO SKINS AND
PRELIMINARY EVALUATION OF THE INSECTICIDAL ACTIVITY
K. Carbone1, E. Santangelo2*, A. De Angelis1, L. Micheli3, R. Frosinini4, E. Gargani4, C.A. Migliori5, A. Mazzucato6
1CREA, Research Centre for Olive, Fruit and Citrus Crops, Via di Fioranello 52, 00134 Rome, Italy
2CREA Research Centre for Engineering and Agro-Food Processing,
Via della Pascolare 16 00015, Monterotondo (Rome, Italy)
3Department of Chemical Sciences and Technologies, University of Rome “Tor Vergata”,
Via della Ricerca Scientifica, 00133 Rome, Italy
4 CREA, Research Centre for Plant Protection and Certification, via Lanciola 12/A, 50125, Florence, Italy
5CREA Research Centre for Engineering and Agro-Food Processing, Strada delle cacce 73, 10135 Torino
6Dept. of Agricultural and Forestry Sciences, University of Tuscia, Via S.C. de Lellis snc, 01100 Viterbo (Italy)
* E-mail address: enrico.santangelo@crea.gov.it
ABSTRACT: With a view to sustainable production and circular economy, the recovery of biomass otherwise
destined for disposal will be a strategic objective in the near future. Yearly, the tomato industry produces hundreds of
thousands of tons of waste, which could be usefully applied in various sectors. This work proposes the use of the
skins of a hyperpigmented (black-skinned) tomato line for the stabilization of silver nanoparticles. Aqueous extracts
produced from this residue have proven to be suitable for producing silver nanoparticles with an average diameter of
224 nm. Subsequently AgNPs were tested for in vitro cowpea weevil (Callosobruchus maculatus) control. At a
concentration of 20% they proved capable of inducing 52% mortality on adults of the insect. To our knowledge, this
is the first case where the tomato peels were used to synthesize Ag-nanoparticles.
Keywords: nanoparticles, residues, biorefinery, circular economy.
1 INTRODUCTION
Tomato industry produces several thousands of tons
of waste. In recent years, about 5 million tonnes per year
of fresh tomatoes were produced in Italy for processing
industries. The residual mass is composed of a mixture of
tomato peels, crushed seeds, and small amounts of pulp
and can be estimated to about 25% of processed
products [1,2]. The disposal of such biomass leads to a
severe loss of compounds, which can be exploited in the
biorefinery view [3,4].
This new route can be pioneered thanks to the
availability of new genetic materials having a differential
content of antioxidant compounds [57]. A wide
repertoire of tomato variants accumulating different
species of antioxidant molecules is available [8] and
some of these genes have been introduced in the
commercial materials.
Among the array of waste-based products, the chance
of using such residues for a high-valued conversion as the
synthesis of nanoparticles remained unexplored.
Phytochemicals with antioxidant and reducing properties
have a key function as capping agents in nanoparticles
stabilization [9]. Nanoparticles comprise a wide class of
materials with a size of at least less than 100 nm and their
use and application in several sectors, including
agriculture, is increasing [10].
The objectives of the present work were:
1. to analyze the possibility of producing silver
nanoparticles (AgNPs) using an aqueous extract of
hyperpigmented tomato skins as reducing and
capping agent;
2. to evaluate the potential use of the AgNPs as control
agents against the cowpea weevil (Callosobruchus
maculatus, Coleoptera, Bruchidae).
2 MATERIALS AND METHODS
2.1 Tomato skin production
A tomato line producing high amounts of
polyphenols in the skin (Aft_atv) was grown in the open
field following the agronomic practices used for the
cultivation of processing tomato with indeterminate
habitus. The line (Fig. 1) originates from a breeding
program aimed at introgressing in the traditional San
Marzano background mutant genes controlling the color
of the pulp and/or the skin of tomato fruit. Details of the
program are reported in [8]. Briefly, the hyperpigmented
line was generated crossing the original WT (a San
Marzano accession from Salerno, Italy, collected in 1973)
with the donors of the mutations. Positive phenotypic
selection was applied to recover the introgressed
mutation and the recurrent parent phenotype. Double
mutant plants were selected based on the expected
phenotype and selfed to fix the mutations [8]. At
ripening, the fruits were used as a source of
hyperpigmented tomato skins (TS) and seeds. Both were
separated from the pulp by an electric tomato squeezer
(type, Bialetti, Italy). The sauce was discarded, and the
TS were stored at -20°C until use.
Figure 1: Examples of the fruits with red (WT) and black
skin (Aft_atv). The latter was used for the study.
2.2 Preparation and preliminary characterization of water
TS extract (TSE)
The tomato peels were first freeze-dried for 48 hours
and then extracted in water by microwave [9]. In short,
0.5 g of freeze-dried TS were added to 10 ml of milliQ
water and the solution was subjected to microwave-
assisted extraction (MAE), using a domestic microwave
operating at 500 W for 20 s. Then, 5 ml of milliQ water
was added to the resulting mixture and placed under
magnetic stirring (750 rpm) for 30 min, at room
temperature and in the dark, to avoid photo-oxidation
28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual
656
phenomena. The mixture was then centrifuged at 3360
rpm for 20 min and the supernatant recovered and used in
the biosynthesis of AgNPs, as reducing and stabilizing
agent (capping agent). TSE was characterized as follows:
the pH value was measured using a digital pH-meter (785
DMP, Methrom, Milan, Italy); the reducing capacity of
TSE was assessed by Folin-Ciocalteu reagent and
expressed as mg gallic acid equivalents (GAE) L-1 [9],
while its antiradical capacity, assessed by ABTS in vitro
test, was expressed in terms of EC50, according to
Ciccoritti et al. [11].
2.3 Green synthesis of silver nanoparticles
Silver nanoparticles were synthesized with the
assistance of microwave (MW) irradiation, according to
the protocol described by Carbone et al. [9], with some
modifications. Briefly, silver NPs were synthesized in a
domestic microwave oven (Whirlpool MWD27, Italy)
operating at 600 W and 2450 MHz for 35 s for cycle (n.
cycles: 10), mixing 4 mL of AgNO3 (1mM), 300L of
TSE and milliQ water up to a final volume of 8 mL. The
bio-reduction of Ag+ ions to AgNPs was followed by the
visual observation of the color change of the solution
from colorless to brownish-yellow and then confirmed by
UVvis spectral analysis. Free biomolecules not absorbed
onto AgNPs were then removed by repeated
centrifugation at 15,000g for 20 min at 4 °C, followed by
dispersion of the pellet in milliQ water.
2.4 UVvis characterization of TSE- mediated AgNPs
Preliminary characterization of TSE-mediated silver
nanoparticles was carried out using UVvis spectroscopy
(Evolution 300, THERMO Scientific, Italy). The bio-
reduction of Ag+ ions in solution was monitored in the
wavelength range of 250700 nm, at a resolution of 0.5
nm (scan speed: 120 nm min-1; data interval: 0.2 nm) and
using autoclaved milliQ water as the blank.
2.5 Laboratory bioassays
Preliminary assays were performed using TS-
mediated AgNPs to verify their effect against cowpea
weevil (Callosobruchus maculatus, Coleoptera,
Bruchidae), a common pest of stored legumes [12].
Healthy seeds of cowpea (Vigna unguiculata L.) were
sprayed with two different dosages of nanoparticles. The
seeds were subsequently exposed to insect infestation.
Ten g of beans were placed in small jars with a lid
protected by a metal mesh. In each jar, the nanoparticles
were distributed at 10 (dosage A) and 20% (dosage B) of
nanoparticles. For both the dosages, a corresponding
control (water without nanoparticles) was included. Each
treatment was replicated five times.
After the application of the nanoparticles and the
subsequent homogenization of the substrate, 10 adults of
C. maculatus from the CREA DC laboratories were
closed in each jar (50 individuals per treatment) and
maintained at environmental conditions (room
temperature and natural light).
The jars were checked at 1, 3, and 7 days from the
placement of the adults, counting the living and the dead
individuals present in the treatments and the control. The
effectiveness of the treatments was calculated using the
Abbott Index [13].
3 RESULTS AND DISCUSSION
3.1 Production of silver nanoparticles
Previous studies highlighted the role of polyphenols
in plant extracts as reducing/capping agent in the green
synthesis of metallic nanoparticles [9]. In a previous
study, the spectrophotometric analysis of the skins [14]
revealed as the hyperpigmented line accumulates high
contents of bioactive compounds. The polyphenols
resulted 2.7-fold higher than the WT (92.8±4.3 vs
34.5±1.3 mg 100 g-1DW, respectively). Based on these
results, the use of the hyperpigmented skins of the
Aft_atv line was deemed highly suitable to produce silver
nanoparticles. In the present study, an aqueous TSE with
an initial standardized TPC of 235 mg L-1 was used in all
synthesis experiments (Table I).
Table I. Physical-chemical characteristics of TSE (mean
± s.d.).
Parameter
Value
pH
4.5 ± 0.1
TPCa
235 ± 22
EC50b
21.70 ± 0.01
aTPC: total phenolic content (expressed in terms of
mg gallic acid equivalents (GAE) L-1);
bEC50 expressed in terms of g mL-1 of TSE causing
the quenching of 50% of ABTS
The bio-reduction of Ag+ ions in solution was
monitored by visual observation and confirmed by using
UV-Vis spectral analysis. A clear Surface Plasmon
Resonance (SPR) band 407 ± 8 nm was observed,
indicating the production of AgNPs (Fig. 2). Nano-sized
rounded particles with an average diameter of 224 nm
were obtained.
Figure 2: UVvis absorption spectra of TSE (pink line)
and TSE-mediated AgNPs
3.2 Laboratory bioassays
The use of nanoparticles for the control of insects has
received particular emphasis in the latest years and
several studies reported promising results. The synthesis
essentially involved the use of biological components (as
plant extracts) to ensure the stabilization of the
nanoparticles in aqueous suspensions [15].
The results of the present study showed a quite
effectiveness of the tested products in controlling the
infestation of cowpea weevil. The TSE-AgNPs
concentration at 20% (Dosage B) caused 52% of
mortality (Abbott index) in the treated adults, three days
after treatment (Table II). Different mechanisms of action
have been proposed concerning the AgNPs toxicity.
Among these, accumulation of reactive oxygen species
28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual
657
(ROS), developmental damages, cuticular
demelanization. However, some uncertainty remains
about the cause of the toxicity, to the nanomaterial itself
or ions generated by it [15].
Table II. Percentage of mortality of C. maculatus treated
with TSE-AgNPs at two different doses
bio-AgNPs
concentration (%)
Abbott index
10
36 %
20
52 %
4 CONCLUSIONS
The present work wished to propose an added-value
application of the recovery of skins extracted from
hyperpigmented tomatoes, combining the most updated
knowledge in three cutting-edge fields: tomato breeding,
circular economy (exploitation of by-products from
agroindustry processing) and nanotechnology.
The recovery of the residues of tomato processing has
been proposed in many fields, but to our knowledge, this
is the first case where the peels were used to synthesize
Ag-nanoparticles. The results showed that the production
of nano-sized particles mediated by TSE is feasible and
that the extract works correctly as a reducing and capping
agent. This application is mainly directed towards the use
of residues that currently involve niche markets, but
which, thanks to their potential, can have a high added
value. As part of increasing attention towards the
consumption of food containing functional molecules,
some seed companies have activated breeding lines
aimed at the selection of tomato varieties with black (or
even yellow and orange) peel, also for industrial
processing.
A preliminary evaluation of the potential applications
of synthesized green nanostructures was addressed
towards the storage of pulse seeds. At this stage, insect
infestation is currently controlled using chemical
pesticides, which can lead to serious problems associated
with human and environmental health [12]. The present
study evidenced as the use TSE-AgNPs can be viewed as
a green alternative option to control the cowpea weevil.
The results are promising and pave the way for
further insights into the use of these new technologies in
plant protection, particularly for pest control of stored
products in the post-harvest/pre-storage phase. However,
further research is needed both to understand the
mechanisms of action and to find the right dosages and
formulations of these new materials.
5 REFERENCES
[1] J. Bacenetti, D. Duca, M. Negri, A. Fusi, M. Fiala,
Mitigation strategies in the agro-food sector: The
anaerobic digestion of tomato purée by-products.
An Italian case study, Sci. Total Environ. 526
(2015) 8897.
https://doi.org/10.1016/j.scitotenv.2015.04.069.
[2] F. Boccia, P. Di Donato, D. Covino, A. Poli, Food
waste and bio-economy: A scenario for the Italian
tomato market, J. Clean. Prod. 227 (2019) 424
433. https://doi.org/10.1016/j.jclepro.2019.04.180.
[3] R. Ciriminna, A. Fidalgo, F. Meneguzzo, L.M.
Ilharco, M. Pagliaro, A.R. Pais, Lycopene:
Emerging Production Methods and Applications of
a Valued Carotenoid, ACS Sustain. Chem. Eng. 4
(2015) 643650.
https://doi.org/10.1021/acssuschemeng.5b01516.
[4] Z. Lu, J. Wang, R. Gao, F. Ye, G. Zhao,
Sustainable valorisation of tomato pomace: A
comprehensive review, Trends Food Sci. Technol.
86 (2019) 172187.
https://doi.org/10.1016/j.tifs.2019.02.020.
[5] A. Mazzucato, D. Willems, R. Bernini, M.E.
Picarella, E. Santangelo, F. Ruiu, F. Tilesi, G.
Piero, Novel phenotypes related to the breeding of
purple-fruited tomatoes and effect of peel extracts
on human cancer cell proliferation, Plant Physiol.
Biochem. 72 (2013) 125133.
https://doi.org/10.1016/j.plaphy.2013.05.012.
[6] F. Blando, H. Berland, G. Maiorano, M. Durante,
A. Mazzucato, M.E. Picarella, I. Nicoletti, C.
Gerardi, G. Mita, Ø. Andersen, Nutraceutical
characterization of cnthocyanin-rich fruits produced
by “Sun Black” Tomato Line, Front. Nutr. 6
(2019). https://doi.org/10.3389/fnut.2019.00133.
[7] R. Ilahy, M.W. Siddiqui, I. Tlili, A. Montefusco, G.
Piro, C. Hdider, M.S. Lenucci, When color really
matters: horticultural performance and functional
quality of high-lycopene tomatoes, CRC. Crit. Rev.
Plant Sci. 37 (2018) 1553.
https://doi.org/10.1080/07352689.2018.1465631.
[8] G. Dono, M.E. Picarella, C. Pons, E. Santangelo,
A. Monforte, A. Granell, A. Mazzucato,
Characterization of a repertoire of tomato fruit
genetic variants in the San marzano genetic
background, Sci. Hortic. (Amsterdam). 261 (2020)
Published online.
https://doi.org/10.1016/j.scienta.2019.108927.
[9] K. Carbone, M. Paliotta, L. Micheli, C. Mazzuca, I.
Cacciotti, F. Nocente, A. Ciampa, M.T. Dell’Abate,
A completely green approach to the synthesis of
dendritic silver nanostructures starting from white
grape pomace as a potential nanofactory, Arab. J.
Chem. 12 (2019) 597609.
https://doi.org/10.1016/j.arabjc.2018.08.001.
[10] A.J. Anderson, The power of being small:
nanosized products for agriculture, Res. Plant Dis.
24 (2018) 99112.
http://files/4704/SC000032037.html.
[11] R. Ciccoritti, M. Paliotta, L. Centioni, F.
Mencarelli, K. Carbone, The effect of genotype and
drying condition on the bioactive compounds of
sour cherry pomace, Eur. Food Res. Technol. 244
(2018) 635645. https://doi.org/10.1007/s00217-
017-2982-3.
[12] M.A.M. Osman, M. Mahmoud, K. Mohamed,
Susceptibility of certain pulse grains to
Callosobruchus maculatus (F.) (Bruchidae:
Coleoptera), and influence of temperature on its
biological attributes, J. Appl. Plant Prot. 3 (2015)
915. https://doi.org/10.21608/japp.2015.7708.
[13] W.S. Abbott, A Method of Computing the
Effectiveness of an Insecticide, J. Econ. Entomol.
18 (1925) 265267.
https://doi.org/10.1093/jee/18.2.265a.
[14] E. Santangelo, M. Carnevale, C.A. Migliori, A.
Mazzucato, M.E. Picarella, G. Dono, F. Gallucci,
Tomato genetic variants for peel color, a source of
biocompounds and biomass for energy recovery, in:
28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual
658
Proc. 27th Eur. Biomass Conf. Exhib., Lisbon,
Portugal, 2019: pp. 18181823.
[15]G. Benelli, Mode of action of nanoparticles against
insects, Environ. Sci. Pollut. Res. 25 (2018) 12329
12341. https://doi.org/10.1007/s11356-018-1850-4.
6 ACKNOWLEDGEMENTS
The authors are thankful to Prof. Ilaria Cacciotti for
morphological analysis of TSE.
This research did not receive any specific grant from
funding agencies in the public, commercial, or not-for-
profit sectors. The production of fruits and skins of the
hyperpigmented tomato line was part of the AGROENER
project (D.D. n. 26329, 1st april 2016 -
http://agroener.crea.gov.it/) supported by the Italian
Ministry of 508 Agriculture (MiPAAF).
28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual
659
... Their unique properties make them a promising solution for protecting the ecosystem. In this regard, Santangelo and colleagues [121] found that using biosynthesized Ag-NPs support in cowpea weevil morbidity. ...
... Silver nanoparticles (AgNPs) at a concentration of 20% using an aqueous extract of hyperpigmented tomato skins resulted in 52% mortality of adults cowpea weevil (C. maculatus) (Carbone et al., 2020). Leaves extract taken from peach tree treated with AgNPs and ZnNPs showed 100% mortality of rice weevil (S.oryzea) and the lesser grain borer (R.dominica) by the fumigation method (Mosa et al., 2021). ...
Article
Full-text available
Globally, between one quarter and one-third of total grains produced each year are lost during storage mainly through infestation of insect pests. Among the available control options such as chemical and physical techniques, fumigation with aluminum phosphide (AlP) is so far considered the best control strategy against storage insect pests. However, these insect pests are now developing resistance against AIP due to its indiscriminate use due to non-availability of any effective alternative control option. Resistance to AIP among storage insect pests is increasing, and its inhalation has shown adverse effects on animals and human beings. Nanotechnology has opened up a wide range of opportunities in various fields such as agriculture (pesticides, fertilizers, etc.), pharmaceuticals, and electronics. One of the applications of nanotechnology is the usage of nanomaterial-based insecticide formulations for mitigating field and storage insect pests. Several formulations, namely, nanoemulsions, nanosuspensions, controlled release formulations, and solid-based nanopesticides, have been developed with different modes of action and application. The major advantage is their small size which helps in proper spreading on the pest surface, and thus, better action than conventional pesticides is achieved. Besides their minute size, these have no or reduced harmful effects on non-target species. Nanopesticides can therefore provide green and efficient alternatives for the management of insect pests of field and storage. However, an outcry against the utilization of nano-based pesticides is also revealed. It is considered by some that nano-insecticides may also have hazardous effects on humans as well as on the environment. Due to limited available data, nanopesticides have become a double-edged weapon. Therefore, nanomaterials need to be evaluated extensively for their large-scale adoption. In this article, we reviewed the nanoformulations that are developed and have proved effective against the insect pests under postharvest storage of grains.
Article
Full-text available
Plants, algae, fungus, yeast, and other creatures all contain a wide variety of biomolecules, making nature a giant "bio-laboratory." Unsurprisingly, a wide range of biomolecules and synthetic techniques may be used to create nanoparticles of different sizes and forms. The production of variously sized and shaped molecules with a variety of qualities, including safety for the environment, plants, animals, and all useful species, is sped up by naturally existing biomolecules. There are several, ecologically friendly techniques for creating nanoparticles that use a variety of substances and compounds. Vegetables, fruits, ornamental plants, field crops, insect pests, and other factors that are density-dependent reduce crop quality and productivity in nature. During the previous decade, synthetic pesticides were employed to control insect pests, but their destructive usage causes resistance, environmental pollution, pest rebound, and negative effects on people, animals, and beneficial fauna. Pesticide residues are detrimental to human health, having both lethal and many chronic effects. Worldwide, a number of countries have shifted from chemical-based agriculture to organic agriculture, which is more cost-effective, socially beneficial, and environmentally sustainable. At the moment, nanotechnology has changed agriculture, with nanotechnology-based insecticides showing the most potential for the long-term management of insect pests. The most common techniques for creating nanoparticles are physical, chemical, and many others; however, chemical techniques are once more thought to be bad for the environment and people's health. In this review article, we'll concentrate on the benefits, recent advancements, difficulties, and prospects for using nanotechnology to manage insect infestations. A number of metals, including zinc (Zn), titanium (Ti), silver (Ag), and zirconium (Zr), with varying features and attributes for the environmentally responsible control of insect pests, are used in the manufacture of nanoparticles.
Chapter
Agricultural and environmental issues are intricately linked to one another. Technological advancements and the development of knowledge databases have provided new impetus to sustainable agriculture.
Chapter
Full-text available
A "pest of stored products" is any organism that infests and degrades stored food, causing both quality and quantitative losses. It is estimated that one-quarter to one-third of the total grain production is lost each year during storage. Insect infestation is responsible for a large portion of this loss. Furthermore, insect damage drastically reduces the quality of grain that is not lost. Many grain pests selectively devour grain embryos, limiting feed grain protein content and the proportion of seeds that germinate. The modern idea of pest management has grown out of the concepts of integrated pest control, which takes into account economic threshold factors, the use of biopesticides derived from natural products, and biocontrol utilizing natural enemies or entomopathogenic organisms. However, it has been shown that the multi-active properties of plant-based bioinsecticides, which are usually chosen in the control of pests in storage grains, can contribute to the creation of toxicity and chemical resistance in insects. In order to manage insect pests, it is therefore realized that a preventative strategy that is favourable to the environment might be used. Herein, the development of nano-enabled bioinsecticide formulae has been greatly influenced by several advancements in nanotechnology. The distribution capabilities and application efficacy of these new
Article
Full-text available
With the popularity of nanotechnology, the use of nanoparticles in pest management has become widespread. Nanoformulated pesticides have several advantages over conventional pesticide formulations, including improved environmental stability, controlled release of active ingredients, increased permeability, targeted delivery, etc. Despite these advantages, recent research shows that several nanoparticles used in conventional nanopesticide formulations can be toxic to crops and beneficial organisms due to bioaccumulation and trophic transfer. Therefore, traditional nanopesticides are thought to be non-advantageous for “green agriculture”. In assessing the current situation, developing “all-organic” nanopesticides could be the next-generation weapon for reducing the adverse impact of traditional nanopesticides. However, their formulation and application knowledge is remarkably limited. The green synthesis of “all-organic” nanoparticles makes them more environmentally friendly than conventional nanopesticides due to their minimal residual and hazardous effects. This review focuses on the current development scenario of “all-organic” nanopesticides, their advantages, and potential effects on target organisms compared to traditional nanopesticides.
Article
Full-text available
Tomato (Solanum lycopersicum L.) is one of the most cultivated vegetable in the world and it represents a large source of bioactive compounds, including carotenoids and polyphenols (phenolic acids and flavonoids). However, the concentration of flavonoids in tomato is considered sub-optimal, particularly because anthocyanins are not generally present. Therefore, this crop has been the object of an intense metabolic engineering in order to obtain anthocyanin-enriched tomatoes by using either breeding or transgenic strategies. Some wild tomato species, such as S. chilense and S. cheesmaniae, biosynthesize anthocyanins in the fruit sub-epidermal tissue, and some alleles from those genotypes have been introgressed into a new developed purple tomato line, called “Sun Black” (SB). It is a tomato line with a purple skin color, both in green and in red fruit stages, due to the biosynthesis of anthocyanins in the peel, and a normal red color pulp, with a taste just like a traditional tomato. SB is the result of a breeding programme and it is not a genetically modified (GM) product. We report the chemical characterization and structure elucidation of the attractive anthocyanins found in the peel of SB tomato, as well as other bioactive compounds (carotenoids, polyphenols, vitamin C) of the whole fruit. Using one- and two-dimensional NMR experiments, the two main anthocyanins were identified to be petunidin 3-O-[6″-O-(4‴-O-E-p-coumaroyl-α-rhamnopyranosyl) -β-glucopyranoside]-5-O-β-glucopyranoside (petanin) and malvidin 3-O-[6″-O-(4‴-O-E-p-coumaroyl-α-rhamnopyranosyl)-β-glucopyranoside]-5-O-β-glucopyranoside (negretein). The total anthocyanins in the whole ripe fruit was 1.2 mg/g dry weight (DW); 7.1 mg/100 g fresh weight (FW). Chlorogenic acid (the most abundant phenolic acid) was 0.6 mg/g DW; 3.7 mg/100 g FW. The main flavonol, rutin was 0.8 mg/g DW; 5 mg/100 g FW. The total carotenoid content was 211.3 μg/g DW; 1,268 μg/100 g FW. The total phenolic content was 8.6 mg/g DW; 52.2 mg/100 g FW. The vitamin C content was 37.3 mg/100 g FW. The antioxidant activities as measured by the TEAC and ORAC assays were 31.6 and 140.3 μmol TE/g DW, respectively (193 and 855.8 μmol TE/100 g FW, respectively). The results show the unique features of this new tomato genotype with nutraceutical properties.
Article
Full-text available
A simple, eco-friendly, cost-effective and rapid microwave-assisted method has been developed to synthetize dendritic silver nanostructures, composed of silver nanoparticles (AgNPs), using white grape pomace aqueous extract (WGPE) as both reducing and capping agent. With this aim, WGPE and AgNO3 (1mM) were mixed at different ratio, and microwave irradiated at 700 watt, for 40 s. To understand the role of bioactive compounds involved in the green synthesis of AgNPs, preliminary chemical characterization, FT-IR analysis and 1H-NMR metabolite profiling of WGPE were carried out. The effects of bioactive extract concentration and stability over time on AgNPs formation were also evaluated. WGPE-mediated silver nanostructures were then characterized by UV-vis, FTIR analyses, and scanning electron microscopy. Interestingly, the formation of dendritic nanostructures, originated from the selfassembly of Ag rounded nanoparticles (average diameter of 33 ± 6 nm), was observed and ascribed to the use of microwave power and the presence of organic components within the used WGPE, inducing an anisotropic crystal growth and promoting a diffusion-limited aggregation mechanism. The bio-dendritic synthetized nanostructures were also evaluated for potential applications in bio-sensing and agricultural fields. Cyclic voltammetry measurements in 0.5 M phosphate + 0.1 M KCl buffer, pH 7.4 showed that green AgNPs possess the electroactive properties typical of AgNPs produced using chemical protocol. The biological activity of synthetized AgNPs was evaluated by in-vitro antifungal activity against F. graminearum. Additionally, a phytotoxicity evaluation of synthetized green nanostructures was carried out on wheat seed germination. Results highlighted the potential of WGPE as green agent for bio- inspired nanomaterial synthesis, and of green Ag nanostructures, which can be used as antifungal agent and in biosensing applications.
Article
Full-text available
The employment of nanoparticles obtained through various synthesis routes as novel pesticides recently attracted high research attention. An impressive number of studies have been conducted to test their toxic potential against a wide number of arthropod pests and vectors, with major emphasis on mosquitoes and ticks. However, precise information on the mechanisms of action of nanoparticles against insects and mites are limited, with the noteworthy exception of silica, alumina, silver, and graphene oxide nanoparticles on insects, while no information is available for mites. Here, I summarize current knowledge about the mechanisms of action of nanoparticles against insects. Both silver and graphene oxide nanoparticles have a significant impact on insect antioxidant and detoxifying enzymes, leading to oxidative stress and cell death. Ag nanoparticles also reduced acetylcholinesterase activity, while polystyrene nanoparticles inhibited CYP450 isoenzymes. Au nanoparticles can act as trypsin inhibitors and disrupt development and reproduction. Metal nanoparticles can bind to S and P in proteins and nucleic acids, respectively, leading to a decrease in membrane permeability, therefore to organelle and enzyme denaturation, followed by cell death. Besides, Ag nanoparticles up- and downregulate key insect genes, reducing protein synthesis and gonadotrophin release, leading to developmental damages and reproductive failure. The toxicity of SiO2 and Al2O3 nanoparticles is due to their binding to the insect cuticle, followed by physico-sorption of waxes and lipids, leading to insect dehydration. In the final section, insect nanotoxicology research trends are critically discussed, outlining major challenges to predict the ecotoxicological consequences arising from the real-world use of nanoparticles as pesticides.
Article
Full-text available
Sour cherry (Prunus cerasus L.) contains substantial quantities of phenolic compounds, specifically anthocyanins, and is mainly processed into different products including juice, whose by-product, namely sour cherry pomace (SCP), represents a potential source of high-added bioactive compounds currently underutilized. Oven-drying (OD) and freeze-drying (FD) are simple methods, often used to stabilize food matrices, and can be also successfully employed for the stabilization of sour cherry pomace. In the present study, the influence of genotype (Bianchi d’Offagna and Montmorency cvs), drying method and their interaction on the extractability of phenolic and anthocyanin profiles of sour cherry pomace were evaluated. Both genotype and drying method significantly influenced (p ≤ 0.001) the overall phytochemical content (total monomeric anthocyanin, total flavan-3-ol, total phenolic, and vitamin C) of analysed pomaces. The interrelationships between the parameters analyzed, the genotype, and the different drying conditions, as well as the relationships among variables, were investigated by principal component analysis (PCA). PCA results pointed out that the phytochemical content of sour cherry pomace was firstly influenced by the cultivar (which accounted for about 70% of the total variance), followed by drying process (about 18% of the total variance), and their interaction (about 12% of the total variance), with the exception of total flavan-3-ols, where a similar contribution (about 50%) of the two factors was observed. Besides, antidiabetic potential of SCPs was also investigated, pointing Bianchi D’Offagna FD pomace as the most active. Obtained results point out the SCP stabilized by means of freeze-drying process as a valuable second-generation biorefinery for the food supplements, nutraceutical and pharmaceutical markets.
Article
San Marzano (SM) is a worldwide famous tomato Italian traditional landrace characterized by elongated fruits with a dual-purpose use in the fresh and processing market. A repertoire of mutations affecting the fruit and of interest for commercial breeding were introduced into the SM genetic background following backcross schemes. The lines generated included 13 genotypes each carrying a single mutation in genes controlling a) the content of all pigments (hp-1, hp-2, pd), b) of carotenoids (r, t, at, B, B_moB), c) of chlorophyll (gf), d) of flavonoids (y) or e) the ripening process (Nr, rin, Gr). Five lines carrying a combination of two mutations were also included. Analysis of SNP polymorphisms showed that the genetic distance of the lines from the recurrent parent was very variable and not well predicted by the number of backcrosses because it was also a function of the dissimilarity of the donor parent. All the genotypes, together with an SM control, were grown in two consecutive years and characterized for vegetative, reproductive and fruit quality traits. Overall, the studied lines reproduced the SM typical phenotypes, but several differences also emerged as both possible negative or advantageous pleiotropic traits for fresh or processing uses and peeling. High pigment mutations confirmed the negative pleiotropic effects on plant fertility and fruit development described earlier and also negatively affected fruit post-harvest life. These latter defects were also reported in the carotenoid mutant tangerine. In contrast, absence of peel pigmentation in the y mutant was associated with positive postharvest properties as those fruit presented higher resistance to wrinkling and dehydration. Delayed ripening mutants showed positive post-harvest phenotypes, as expected. In conclusion, the study of the present repertoire of fruit variations in an elongated tomato genotype represents a contribution to expand the study of fruit physiology to unusual fruit types and to breed innovative tomato lines with valuable nutritional and technological properties.
Article
Food wastes display a great potential for waste-based biorefineries in the frame of a bio-economy system. The bio-economy is an innovative economy model based on the sustainable use of renewable resources in agriculture and industry, and that takes in account biodiversity and environmental protection. To this aim, some key factors are need: the development of new technologies and processes, the identification of renewable feedstock not in competition with other production chains, the creation of new markets and competitiveness, the pushing of policymakers and stakeholders to work more closely together. Tomato industry, that is one of the most important sector of the world food industry, can display an enormous potential since it produces huge amounts of wastes. Such residues negatively impact on the sustainability of food industry, since their disposal represents one main issue in terms of environmental and economic impact. Nevertheless, they represent a cheap and renewable biomass that, in the frame of the biorefinery model, could be exploited for the production of chemicals and energy thus contributing to the sustainability of this production chain. In this paper the potentiality of the tomato-wastes biorefinery was investigated with particular regard to the Italian scenario. Some main aspects were investigated including the possible re-use strategies and the available examples of tomato wastes conversion into marketable products. The analysis of the state of the art showed that tomato wastes recycling in Italy is till limited. Indeed, the scalability of such processes at an industrial scale still remains to be assessed in order to open the way to new markets based on the exploitation of tomato wastes.
Article
Background A large amount of tomato pomace is produced from industrial processing, most of which is not properly utilized. This not only causes a waste of valuable resources but also increases the environmental burden. Scope and approach Summarizing the proximate composition of tomato pomace, this review mainly discussed its comprehensive utilization in animal feed, as a food ingredient, and in recovering valuable components, such as lycopene, dietary fibre, tomato seed oil and protein. Key finding and conclusions Tomato pomace, including peels and seeds, is produced as a by-product in the food industry. The peel component of tomato pomace is rich in dietary fibre and lycopene, while the seed component contains high levels of oil and protein. Smashed, fermented or silaged, all parts of tomato pomace can be used in animal feed to increase the nutritional value of daily ration. The fine powders of tomato pomace and its peel and seed component can be applied as functional food ingredients to be incorporated into wheat flour-based foods, meat products and tomato paste to improve the nutritive, textural and sensory quality of the involved foods. Furthermore, tomato pomace and its component are good sources of lycopene, dietary fibre, pectin, protein and oil through the specific extraction method, which is a current research hotspot that aims to make the industry sustainable. Further studies should expedite these technologies and products to a large-scale process and practical application.
Article
Introgression of spontaneous or induced mutations has been used to increase the levels and diversify the profile of antioxidants in many fruits including tomato. The high-pigment (hp) and old-gold (og) alleles exemplify this approach as attractive genetic resources suitable to inbred elite high-lycopene (HLY) tomato lines with improved color and nutritional attributes. Although several studies have been published on HLY tomatoes, a systematic analysis of the information on their agronomic performances, processing features, and functional quality is lacking, leaving room for the assumption of their poor competitiveness with conventional tomato cultivars and limiting their agricultural diffusion. Therefore, the aim of this study is to critically review the most important agronomic, horticultural, and functional traits of HLY tomatoes, as well as the advances in some emerging (pre)industrial applications. Field experiments performed in different countries showed that most available HLY lines are productive, vigorous, with excellent foliage cover and with morphologically acceptable fruit. Tomato yield of HLY genotypes ranged from ∼30 to ∼178 t/ha exceeding, in some trials, that of highly productive cultivars. Red-ripe fruits of most HLY lines showed commercially suitable soluble solids and titratable acidity, in addition to increased levels of lycopene (up to 440 mg/kg fw) and other bioactive phytochemicals (mainly flavonoids and vitamin C) compared to their near isogenic conventional counterparts. Innovative (pre)industrial uses of HLY tomato include the following: (1) production of HLY sauces, juices, and powders; (2) supercritical-CO2 extraction of lycopene containing oleoresins; and (3) preparation of lycopene rich micro- and nano-carriers with improved stability and specific tissue delivery. In turn, the use of these innovative high-quality ingredients in the formulation of lycopene fortified foods, cosmetic products, nutraceuticals, and pharmaceuticals has been proposed as the basis of a novel highly profitable tomato product chain.
Article
Lycopene, a carotenoid used as natural colorant for decades, is a powerful antioxidant abundant in tomatoes and other red fruits. Following studies in the context of health started some 30 years ago, lycopene is emerging as a valued antioxidant with many new applications as nutritional supplement and active ingredient in cosmetic products. This study provides an overview of the emerging utilization and extraction methods in the context of intense fundamental and applied research that is eventually unveiling the full potential of this important terpene.