ArticlePDF Available

Lycopene content in hydroponic and non-hydroponic tomatoes during postharvest storage


Abstract and Figures

The lycopene content in hydroponic and non-hydroponic ripe tomatoes increased from 36 µg/g fresh weight to maximum amounts after 14 days storage at 22oC, reaching 89.75±4.51 and 115.13±2.08 µg/g fresh weight for hydroponic and non-hydroponic tomatoes respectively. Non-hydroponic tomatoes showed also a significant increase (P<0.05) in red colour when stored at 22oC. Storage at 4oC suppressed lycopene formation and red colour development in both cultivars.
Content may be subject to copyright.
S. Ajlouni 1, S. Kremer 2, and L. Masih 1.
The initial lycopene content in hydroponic and non-hydroponic ripen tomato fruits
was about 36 μg/g fr. wt., and increased continuously during postharvest storage.
Maximum amounts of lycopene were recorded after 14 days of storage at 22oC,
and reached 89.75±4.51 μg/g fr. wt. and 115.13±2.08 μg/g fr. wt. for hydroponic
and non-hydroponic cultivars, respectively. Non-hydroponic tomatoes showed also
a significant increase (p<0.05) in red colour when stored at 22oC. Storage at
refrigeration temperature (4oC) suppressed lycopene formation and red colour
development in both cultivars.
1 The Department of Food Science and Agribusiness
Gilbert Chandler College
Institute of Land and Food Resources
The University of Melbourne
Sneydes Road, Werribee Victoria 3030
Tel: (03) 92175206 Fax: (03) 9741 9396
2 The Department of Home Economic and Nutrition
Fachhochschule Fulda
36012 Fulda
Carotenoids are natural pigments synthesized by plants and some microorganisms
and found in a wide variety of fruits and vegetables. Carotenoids act as light-
absorbing pigments during photosynthesis and protect cells against
photosensitization (Rao, 1999; Clinton, 1998). In addition, some carotenoids, such
as α- and β-carotene play an important role as vitamin A precursors (Van Niekerk,
Lycopene is one of these carotenoids found predominantly in tomatoes, and forms
the principal pigment responsible for the red colour. The content of lycopene
varries widely among tomato varieties and increases dramatically during ripening
(Clinton, 1998). The concentration of lycopene in ripe fruits of the common
variety lycopersicon esculentum ranges between 31-77 μg/g fresh weight (Nguyen,
1999). Recent research and nutritional studies revealed that lycopene exhibits the
highest anitoxidant effect among all major dietary carotenoids (Rao, 1999;
Clinton, 1998). It is believed that dietary lycopene can reduce the risk of chronic
diseases such as cancer and cardiovascular disease (Rao, 1999).
Lycopene is a acyclic carotenoid, insoluble in water, containing 11 conjungated
and 2 non-conjugated double bonds (Rao, 1999; Clinton, 1998). In most foods,
lycopene occurs mainly in the thermodynamical most stable all-trans
configuration. In raw tomatoes, for example, 94-96% of the lycopene can be found
in the all-trans form (Schierle, 1997). However the trans to cis isomerization
occurs mainly during cooking, processing and storage (Rao, 1999; Tonucci, 1995),
and improves the bioavailability of lycopene (Gaertner, 1997, Stahl, 1992).
Lycopene content in hydroponic tomatoes, which represent an important and
growing section in the tomato industry, has not been well investigated. The
production of hydroponic tomatoes has increased significantly during the last few
years. The annual turnover of hydroponic crops in Australia reached $3 million in
1998, with a ten-fold increment in the last decade (Wilson,1999). This study will
report changes in lycopene contents in hydroponic and non-hydroponic cultivars
during storage at refrigeration and room temperatures.
Materials and Methods
Lycopene (90-95% pure) and HPLC grade methylene chloride were obtained from
Sigma Chemical Company (St. Louis, USA). Analytical grade solvents including
hexane, methanol, acetone and toluene as well as HPLC grade methanol were
purchased from British Drug House (BDH Laboratory Supplies, Poole, UK).
Sampling and preparation of lycopene extract
Medium size tomato fruits with similar degrees of maturity, and from two different
cultivars were used in this study. Hydroponic tomatoes (Pyramid) were obtained
from a local grower and non-hydroponic tomatoes were bought from a local
supermarket. Each group of tomatoes was divided into two halves and placed on
trays. One half was stored at room temperature (22°C), and the other half in a
fridge at 4°C. Changes in color and lycopene contents were measured on day zero
and after 7, 14, and 21 days of storage.
Due to the fact that pure lycopene is a very light-sensitive compound, the
extraction was performed under subdued lighting with a 25W red globe providing
the only illumination, following the method of Chen et al., (1995) with slight
About 500 g of tomato were homogenized in a Waring blender (800 E, Dynamics
Corporation of America, Connecticut, USA) and three samples of the homogenate
(4 g each) were collected and treated separately. The homogenate was mixed with
30 ml of hexane:acetone:methanol:toluene, 10:7:6:7 v/v/v/v in a 100ml volumetric
flask, 6 ml of a 4% methanolic KOH was added and the flask was shaken for 1
min and left in the dark at room temperature for 16 h saponification. After
saponification, 30 ml of hexane were added to the flask, followed by gentle
swirling for 1 min, before the mixture was diluted to volume with 1% Na2So4. The
flask was left to stand in the dark for an additional 1h until two phases had
separated. The upper phase was transferred into a rotary evaporator and evaporated
to dryness at 50°C. The dried concentrate was then dissolved in 10 ml of
methanol-methylene chloride 45:55 v/v and filtered through a 0.2 μm membrane.
To minimize oxidation or degradation of the extracted lycopene, 20 μl of that
filtrate were immediately injected into the HPLC.
HPLC system
The chromatographic analyses were performed using a Shimadzu High
Performance Liquid Chromatograph equipped with a workstation computer (Class-
VP) and a photodiode array (PDA) detector (SPD-M10Avp). The column used
was a NOVA PAK C18 stainless steel column of 3.9 x 150 mm packed with C18
reversed-phase material with a particle size of 4 μm (Millipore-Waters Associates,
Lycopene standard was dissolved in chloroform containing 0.1% Butylated
Hydroxytoluene (BHT), divided into 1 ml aliquots and stored at – 80°C. The
elution was performed at room temperature with an isocratic solvent,
methanol:(methanol:methylene chloride, 45:55 v/v) 99:1 v/v, at a constant flow
rate of 1.5 ml/min. The peak response of lycopene was detected at 472nm and the
quantification of the lycopene was performed using the programm Excel
(Microsoft, USA).
Colour measurement
A Minolta Chroma Meter CR-300 (Minolta Co., Ltd., Japan) was used to measure
the L, a & b color space values of whole tomato fruits before homogenisation.
Statistical Analysis of Data
Data were statistically analyzed using SPSS 8.0. for WIN 95/NT and a student T-
test was performed to compare between the means at 95% confidence level.
a. Lycopene Contents:
The initial lycopene content in ripe hydroponic tomatoes (HT) was 36.15±4.17
μg/g fresh weight (fr. wt.) on day zero of storage. Lycopene content in HT
(Pyramid) increased continuously during storage at room temperature and reached
a maximum value of 89.75 ± 4.51μg/g fr. wt. after 14 days of storage (Fig 1). The
same data revealed also that lycopene content started to decrease after 21 days of
storage, while the tomato fruits were still in a good quality for consumption.
Storage at refrigeration temperature did not affect lycopene content (36.15 ± 4.17
μg/g fr. wt.) in Hydroponic tomatoes, which showed very little changes throughout
the storage period (Fig 1). However, severe senescence and deterioration in the
quality of hydroponic tomatoes were observed after 21 days of storage at 4oC.
Changes in lycopene contents in non-hydroponic tomato (non-HT), as affected by
storage temperature, showed similar patterns to those observed in the hydroponic
cultivars. However the increments in lycopene contents in non-HT stored at room
temperature were significantly (P<0.05) higher than those recorded in HT
throughout the storage period. Lycopene content increased dramatically in non-HT
after 14 days of storage at room temperature and reached a maximum value of
115.13 ± 2.08 μg/g fr. wt. (Fig 1).
Deleted: changes
Figure 1. Changes in lycopene contents of hydroponic (Pyramid) and non-
hydroponic tomatoes during storage at two different temperatures.
HT(4C): Hydroponic tomato stored at 4oC; Non-HT(22C): Non-
hydroponic tomato stored at 22oC.
Storage Time (day)
0 7 14 21
Non-HT (22C)
HT (22C)
Non-HT (4C)
HT (4C)
Storage Time (day)
Lycopene content (ug/g fr wt)
b. Colour Measurments
In addition to visual evaluation of the degree of ripeness of tomato fruits, colour
measurements were also recorded throughout the storage period to monitor
changes in tomato red colour as a quality parameter. The three colour space values
(L, a and b) were measured using Minolta Chroma Meter. Positive L, a and b
colour space values reflect the degree of lightness, redness and yellowness,
respectively. Since mature and high quality tomato fruits are usually associated
with intense red colour, the a values can be used as an indicator to estimate
changes in tomato quality during maturation and storage. The larger the a value,
the more intense the red colour of tomato fruits.
Data form colour measurements in hydroponic tomatoes revealed slight changes in
L and b values during storage at 4oC and 22oC. However, changes in a values were
significant (p<0.05) during storage at 22oC. The a values in HT increased from
11.83±2.45 to 17.68±1.05 after the first 7 days of storage (Table 1), and remained
relatively stable thereafter. No significant changes in a values were recorded in HT
stored at 4oC (Table 1).
The red colour of non-hydroponic tomatoes was also affected by storage
temperature as indicated by some significant changes in colour space values. The
a values increased from 5.75±2.61 to 9.26±1.49 after the first 7 days of storage at
4oC, and such increment was more significant at 22oC (Table 2). The L value in
non-hydroponic tomatoes decreased from 48.32±2.22 to 40.86±0.81 during storage
at 22oC, while no major changes in b values were detected in non-HT throughout
the storage period.
Table 1. Changes in colour space values (L, a & b) in hydroponic tomatoes during storage for 21 days at two different temperatures.
Storage Temperature
Storage Time (days)
L a b L a b
42.60 ± 1.72 *
42.95 ± 0.73
43.96 ± 1.24
41.38 ± 1.81
11.83 ± 2.45
8.22 ± 1.80
9.25 ± 1.51
10.77 ± 3.23
20.89 ± 1.01
24.25 ± 1.16
24.12 ± 1.04
24.81 ± 3.10
42.60 ± 1.72
39.77 ± 0.96
38.64 ± 0.96
37.91 ± 0.22
11.83 ± 2.45
17.68 ± 1.05
18.54 ± 1.83
18.35 ± 0.95
20.89 ± 1.01
20.98 ± 2.18
20.65 ± 1.87
19.52 ± 1.03
* Values represent the average of six measurements followed by the standard deviation.
Table 2. Changes in colour space values (L, a & b) in non-hydroponic tomatoes during storage for 21 days at two different
Storage Temperature
Storage Time (days)
L a b L a b
48.32 ± 2.11 *
46.31 ± 2.12
44.55 ± 2.27
46.42 ± 1.54
5.75 ± 2.61
9.26 ± 1.49
11.36 ± 2.73
10.94 ± 3.83
23.19 ± 3.60
27.55 ± 5.08
30.67 ± 1.74
28.67 ± 3.10
48.32 ± 2.11
40.86 ± 0.81
39.06 ± 1.07
38.59 ± 0.38
5.75 ± 2.61
21.06 ± 2.39
22.66 ± 1.70
21.53 ± 2.45
23.19 ± 3.60
23.42 ± 2.06
21.32 ± 1.40
20.66 ± 1.55
* Values represent the average of six measurements followed by the standard deviation.
Tomato fruits of both cultivars (hydroponic and non-hydroponic) appeared to have a
similar amount of lycopene at the start of the storage period. The average lycopene
contents were 36.15±4.17 and 36.25±1.24 μg/g fr wt for hyroponic and non-hyroponic,
respectively. These values are in agreement with those reported by Nguyen in 1999, who
indicated that the content of lycopene in ripe fruits of the common variety Lycopersicon
esculentum ranges between 31 and 77 μg/g fr wt.. Lycopene content increased
continuously in both cultivars during storage at 22oC, and reached its maximum values
after 14 days of storage (Fig 1). However, the rate of lycopene formation in non-
hyroponic tomatoes was higher than that in the hyroponic cultivar. The amount of
lycopene in non-HT reached a maximum value of 115.13±2.08 μg/g fr wt in comparison
to 89.75 ±4.51 μg/g fr wt in HT under the same storage conditions. These findings may
suggest that the substrate for lycopene formation (phytoene) was more readily available
in non-HT, and/or the lycopene biosynthesis enzymatic systems were more active in non-
HT. Results of lycopene formation at 4oC may support these suggestions. No significant
changes (p>0.05) in lycopene contents were detected in HT during storage at 4oC, while
non-HT revealed a 68% increase in the amount of lycopene after 14 days of storage at
4oC. However, this percentage increment in lycopene content in non-HT at 4oC was much
smaller than that detected at 22oC (217%) after the same storage period.
These results may indicate that ripe tomatoes “red colour” stored at room temperature
would have higher lycopene contents than tomato fruits kept at refrigeration temperature.
Similar conclusion was reported by Hamauzu et al., (1998) who indicated that lycopene
contents were high in ripe tomatoes stored at 20°C for 10 days. Lycopene is usually
synthesized from phytoene and regarded as the common precursor for β-carotene.
Because the cycle of lycopene formation and degradation is highly regulated by several
biosynthetic enzymes, it can be postulated that storing tomato fruits at refrigeration
temperature may reduce these enzymatic activities and maintain lycopene contents
relatively stable.
Colour space values (L, a & b) of both cultivars were also affected by storage
temperature, and showed similar changes to those observed in lycopene. Storage at low
temperature suppressed red colour development in tomato fruits, as indicated by the
smaller a values at 4oC in comparison with a values at 22oC for both cultivars (Tables 1
& 2). Maximum a values were obtained after 14 days of storage at 22oC. The net
increment in a values were 6.71 and 16.91 units for hydroponic and non-hydrponic
tomatoes, respectively. These observations correlate well with the previous results of
lycopene analysis, which showed more significant increase in non-HT. The fact that
lycopene is the principal pigment responsible for the red colour in tomato, supports these
findings, because more lycopene formation is expected to yield higher a values.
However, it should be noted that such positive relationship between lycopene content and
a values was observed throughout the storage period, except on day zero. Although both
hyroponic and non-hyroponic tomatoes showed similar lycopene contents on day zero
(Fig 1), the a value in HT was larger than that in non-HT (Tables 1 & 2). Such variations
in a values may be related to L values which showed some difference on that day of
measurement. The L values were 42.60 and 48.32 unit for hyroponic and non-
hydroponic, respectively. As L value represents the degree of lightness, larger L values
would be associated with brighter colour and smaller a values. This may explain the
reason for the smaller a values in non-HT compared to HT on day zero of storage.
The higher lycopene contents detected in non-HT compared to the HT fruits during
storage at room temperature may be related to variations in physiological characteristics
between the two cultivars, as well as growing conditions. Lessin reported in 1997 that
carotenoid concentration in fruits and vegetables vary within plant variety, degree of
ripeness, time of harvest, and growing and storage conditions. Storage at refrigeration
temperature (4oC) suppressed lycopene formation and red colour development in both
cultivars. These findings support the recommendations that tomato fruits in general
should be stored at room temperature in order to obtain better red colour and higher level
of lycopene.
Further investigation is needed to thoroughly evaluate chemical composition,
biochemical and physiological changes, and nutritional values of hydroponic tomatoes, as
compared to non-hyrodponic cultivars. The proposed future research project will use
tomato samples of well-identified cultivars, harvested at similar stage of maturity.
Chen, BH, Peng, HY, and Chen, HE. 1995. Changes of carotenoids, color, and vitamin A
contents during processing of carrot juice. J. Agric. Food Chem. 43:1912-1918.
Clinton, KS. 1998. Lycopene: chemistry, biology, and implications for human health and
disease. Nutrition Reviews, Vol. 56, No.2: 35-51.
Gartner, C, Stahl, W, and Sies, H. 1997. Lycopene is more bioavialable from tomato
paste than from fresh tomatoes. Am J Clin Nutr. 66:116-22.
Hamauzu, Y, Chachin, K and Ueda, Y. 1998. Effect of postharvest storage temperature
on the conversion of 14C-mevalonic acid to carotenes in tomato fruit. J. Japan. Soc.
Hort. 67(4): 549-555.
Lessin, WJ, Catigage, GL, and Schwartz, SJ. 1997. Quantification of cistrans isomers of
provitamin A carotenoids in fresh and processed fruits and vegetables. J. Agric. Food
Chem. 45: 3728-3732.
Nguyen, NL, and Schwartz, SJ. 1999. Lycopene: Chemical and biological properties.
Food Technology. Vol. 53, No. 2: 38-44.
Rao, VA, Waseem, Z, & Agarwal, S. 1999. Lycopene content of tomatoes and tomato
products and their contribution to dietary lycopene. Food Research International, Vol.
31, No. 10: 737-741.
Schierle, J, Bretzl, w, Buhler, I, Faccin, N, Hess, Denise, Steiner, K & Schuep, w. 1997.
Content and isomeric ratio of lycopene in food and human blood plama. Food
Chemistry, Vol. 59, No. 3: 459-465.
Stahl, W, and Sies, H. 1992. Uptake of Lycopene and its geometrical isomers is greater
from heat-processed than from unprocessed tomato juice in humans. American
Institute of Nutrition. July 1992, P. 2161-2166.
Tonucci, LH, Holden, JM, Beecher, GR, Khachik, F, Davis, CS, and Mulokozi, G. 1995.
Carotenoid content of thermally processed tomato-based food products. J. Agric.
Food Chem. 43:579-586.
Van Niekerk, PJ. 1988. Determination of vitamins. In Macrae, R. (ed). HPLC in food
analysis. Academic press, London: 133-140.
Wilson, A. 1999. Personal communication. Hyroponic tomato. The president of
hyroponic tomato group. Geelong, Victoria.
Full-text available
Heirloom tomato varieties are in demand by consumers due to high antioxidant levels. However, these varieties are difficult to produce and are prone to disease. To overcome these problems, heirloom tomatoes may be cultivated in hydroponic systems and grafted onto disease-resistant rootstocks. However, it is unknown if the antioxidant content and capacity are affected by grafting. In this study, heirloom (Black Krim and Green Zebra) and standard (Big Beef) varieties were grafted onto wild type (WT) or productive rootstocks (Arnold and Supernatural). The tomatoes were harvested at maturity, freeze-dried, and ground into a powder. Lycopene was extracted using hexane, and the content was determined spectrophotometrically at 503 nm. The antioxidant capacity of methanol extracts was evaluated by the 2,2′-azino-di[3-ethylbenzthiazoline sulfonsyr]sulphonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, whereas the phenolic content was determined using the Folin–Ciocalteu assay. Interestingly, the grafting of Big Beef and Green Zebra onto Supernatural rootstock resulted in an increased antioxidant capacity, as determined by the DPPH assay. Moreover, the phenolic content was changed for Big Beef grafted onto Arnold, and Big Beef and Green Zebra grafted onto Supernatural. Taken together, these results indicate that certain combinations of standard and heirloom tomato varieties and productive rootstocks may influence the antioxidant capacity and phenolic content. These results may be used to guide producers when choosing rootstocks for cultivating hydroponic tomatoes.
Full-text available
There are many different types of systems used to grow food that are distinguished by ideology or the technology used. It is often difficult to directly compare yield and quality in different growth systems due to the complicated interactions between genotype, physiology and environment. Many published comparisons do not identify and acknowledge confounding factors. However, there is urgency to undertake controlled comparisons to identify the most efficient and effective food production systems, because the world faces considerable challenges to food supply with population rise, ongoing environmental degradation and the threat of climatic change. Here we compared soil with two hydroponic growth systems, drip irrigation and deep-water culture (DWC). It is often claimed that such systems differ in water use, yield and crop quality; however, such comparisons are often confounded by assessing plant and system parameters in different growth environments or where factors that are difficult to standardise between systems, such as nutrient status, are not controlled. We grew tomato (Solanum lycopersicum L.) in the three growth systems in two replicated experiments, in either a polytunnel or glasshouse. We controlled and monitored water use and nutrient levels across all systems as different fertilizer applications can influence the nutritional values of produce. Plants in the two hydroponic systems transpired less water and were more water-efficient with a lower product water use than plants grown in soil. Fruit yield was similar and total soluble solids and sugar levels were not significantly different between the three growing systems. However, levels of lycopene and β-carotene were either similar or significantly higher in DWC compared to growth systems using soil or drip irrigation. Our results identify hydroponic systems as more water use efficient with DWC also capable of producing higher quality produce.
Full-text available
The effects of packaging materials [Corrugated fibre boxes (CFB), non-perforated polypropylene pouches (NPPP), perforated polypropylene pouches (PPP), plastic crates (PC), jute bags (JB)] were assessed on quality attributes in open pollinated (OP) and hybrid tomato (Solanum lycopersicum L.) cultivars during ambient storage (24-32oC and 70-85% RH). Tomato OP variety, Kashi Hemant had shown maximum PLW (65.2%) in PC while coded IIVR hybrid 1 exhibited minimum PLW (1.3%) in NPPP after 20 days of storage at ambient storage temperature. The maximum increase in 'a' value was also obtained in PC followed by JB, CFB, PPP and NPPP. Maximum (14.7-25.0 mg/100g) increase in ascorbic acid was obtained in hybrid Kashi Abhiman during 25 days of storage in NPPP whereas, OP variety Kashi Amrit had shown minimum increase (10-18.5 mg/100g) in ascorbic acid in PC after 15 days of storage.
Public awareness of the purported health benefits of dietary antioxidants has increased the demand for fruit and vegetable products with recognized and improved antioxidant quality and has created new opportunities for the horticulture and food industry to improve fruit and vegetable quality by enhancing antioxidant content. This review describes the production and processing factors that influence the content of the major fruit and vegetable antioxidants, namely vitamin C, carotenoids, and phenolics. There is substantial genetic variation in the content of each of these antioxidant types among fruit and vegetable cultivars. Compared with vitamin C and carotenoids, the levels of phenolic antioxidants appear to be more sensitive to environmental conditions both before and after harvest. Although vitamin C can be readily lost during fresh storage, the content of certain carotenoids and phenolics can actually increase during suitable conditions of fresh storage. Vitamin C and phenolics are more susceptible to loss during processing, especially by leaching from plant tissues into processing water. The combination of cultivar variation and responsiveness to specific environmental conditions can create opportunities for the production and processing of fruits and vegetables with improved antioxidant properties.
The time between harvesting and consumption of fruit or vegetables could be up to several weeks. Phytochemical reactions in response to environmental conditions of harvested fruit or vegetables during this period may change the level of biological and medicinal activities of particular compounds. Therefore, quantification of such phytochemical reactions is a critical point in designing nutritional value studies. Red stage ripened cluster tomatoes (Lycopersicon esculentum Mill. cv. Clermon) grown hydroponically in greenhouses were analyzed for variation of lycopene, hydrophilic antioxidant activity (using TEAC assay), total soluble solids and weight loss during two subsequent weeks of storing at 12 and 5 °C in comparison to 7 d room temperature storage as control. Low temperature storage at 5 °C in compare to 12 °C inhibited weight loss and enhancement of lycopene and TSS but antioxidant activity was increased as much as 1.77 times. Room temperature stored tomatoes showed significant increase in lycopene content and weight loss, but no effect on TSS and antioxidant activity during 7 d storage. TSS was not affected either by room temperature or low temperature storage, but weight loss, lycopene content and antioxidant activity at room temperature in compare to low temperature stored tomatoes were significantly different. It seems chilling stress shifts the pathways involved in the biosynthesis of antioxidant active compounds into higher levels of production. The results showed that postharvest environmental conditions need to be considered carefully for evaluation of particular bioactive compounds in fresh fruit and vegetables.
The objective of this study was to study overall nutritional implication of storage on tomatoes (cv. Tradiro), harvested from a commercial greenhouse in Canterbury, New Zealand. The harvested tomatoes were stored at 7, 15 and 25 °C, for a period of 10 days. The soluble phenolics and ascorbic acid contents of tomatoes showed slight increases during storage, regardless of temperature. The mean lycopene content of tomatoes stored at 15 and 25 °C on the 10th day of storage was, approximately, 2-fold (7.5 mg/100 g) than of the tomatoes stored at 7 °C (3.2 mg/100 g). The soluble antioxidant activity increased from 17–27% during the storage period of tomatoes.
Because hydroponic production of vegetables is becoming more common, the carotenoid composition of hydroponic leafy vegetables commercialized in Campinas, Brazil, was determined. All samples were collected and analyzed in winter. Lactucaxanthin was quantified for the first time and was found to have concentrations similar to that of neoxanthin in the four types of lettuce analyzed. Lutein predominated in cress, chicory, and roquette (75.4 +/- 10.2, 57.0 +/- 10.3, and 52.2 +/- 12.6 microg/g, respectively). In the lactucaxanthin-containing lettuces, beta-carotene and lutein were the principal carotenoids (ranging from 9.9 +/- 1.5 to 24.6 +/- 3.1 microg/g and from 10.2 +/- 1.0 to 22.9 +/- 2.6 microg/g, respectively). Comparison of hydroponic and field-produced curly lettuce, taken from neighboring farms, showed that the hydroponic lettuce had significantly lower lutein, beta-carotene, violaxanthin, and neoxanthin contents than the conventionally produced lettuce. Because the hydroponic farm had a polyethylene covering, less exposure to sunlight and lower temperatures may have decreased carotenogenesis.
Full-text available
Lycopene and beta-carotene are the most abundant carotenoids in human blood and tissues. Although lacking provitamin A activity, lycopene may be biologically active by contributing to the antioxidative defense system of the organism. We studied the uptake of lycopene from processed (boiled with 1% corn oil for 1 h) and unprocessed tomato juice in humans. Lycopene concentrations in human serum increased only when processed tomato juice was consumed. Lycopene uptake varied with individuals, but peak serum concentrations were always reached between 24 and 48 h. The carotenoid was eliminated from serum with a half-life of 2-3 d. The increase in peak serum concentrations was dose-dependent but not linear with the dose. Repeated doses led to a continual rise of lycopene in human serum. Of the different geometrical isomers (all-trans, 9-cis and 13-cis), the cis isomers seemed to be somewhat better absorbed than the all-trans form.
Consumption of tomatoes and tomato products has been shown to provide nutritional and health benefits.
The carotenoid metabolism in tomato fruit in relation to high temperature inhibition of pigmentation was investigated with pericarp sections of tomato fruits stored at 20°C, 30°C, and 35 °C. The pericarp sections were incubated with 2-14C-mevalonic acid for 10 hours at the same temperatures as the storage temperatures. When tomatoes were stored longer and at higher temperatures, the radioactivity of lycopene extracted from pericarp sections was low, whereas, that of β-carotene was high. The specific radioactivity of the carotenes decreased in order of the steps of carotenoid biosynthetic pathway, phytoene → lycopene → β-carotene, in all the sections of the fruit stored at each of the temperatures. We postulate from these results that high temperature inhibits the accumulation of lycopene in tomato fruit because the conversion of lycopene to β-carotene is stimulated instead.
A polymeric 5 μm C30 stationary phase for reversed phase HPLC was used to separate and quantitate geometric isomers of provitamin A carotenoids in fresh and processed fruits and vegetables. β-Carotene isomers (all-trans, 9-cis, 13-cis, and 15-cis), α-carotene isomers (all-trans, 9-cis, 13-cis, and 13‘-cis), and β-cryptoxanthin isomers (all-trans, 13 and 13‘-cis, and 15-cis) were resolved isocratically using the C30 stationary phase with 89:11 methanol/methyl tert-butyl ether as mobile phase. The percent of cis isomers increased 10−39% with canning. The total provitamin A carotenoid content (in micrograms per gram of dry weight of tissue) ranged from 3.5 to 907 in fresh samples and from 1.8 to 1055 in canned samples. In several fruits and vegetables, processing produced an increase of 16−50% of total measured provitamin A carotenoids relative to the fresh samples. These increases were most likely a result of increased extraction efficiency, inactivation of enzymes capable of degrading carotenoids, and/or loss of soluble solids into the liquid canning medium. Keywords: β-Carotene; α-carotene; β-cryptoxanthin; C30 reversed phase HPLC; isomers
The effects of various processing methods on carotenoid, color, and vitamin A content changes in carrot juice were studied. Results showed that canning (121 degrees C, 30 min) resulted in the highest destruction of carotenoids, followed by HTST heating at 120 degrees C for 30 s, 110 degrees C for 30 s, acidification plus 105 degrees C heating for 25 s, and acidification. 13-cis-beta-Carotene was formed in largest amount during heating, followed by 13-cis-lutein and 15-cis-alpha-carotene. The formation of 13,15-di-cis-beta-carotene during canning was due mainly to conversion of 13-cis-beta-carotene, Carrot juice color turned from orange to yellow with intensive treatment. The vitamin A content decreased along with increasing temperature and heating time.
Tomato-based food products such as tomato paste, tomato sauce, and tomato-based soups are rich in carotenoid compounds and are frequently consumed in the United States. Foods such as these, which. are high in carotenoid content, are of interest because of the demonstrated association between consumption of fruits and vegetables and reduced risk of lung and other epithelial cancers in humans. Limited analytical data on the carotenoid content of tomato-based products are available in food tables and data bases; however, they are usually reported only in terms of vitamin A activity. In this study name-brand and store-brand tomato-based food products purchased in three major U.S. cities were extracted and carotenoids were individually identified and quantified by reversed-phase HPLC according to methodology developed in our laboratory. The carotenoids that were detected and quantified included lycopene, lycopene-5,6-diol, lutein, alpha-, beta-, gamma-, and zeta-carotenes, neurosporene, phytoene, and phytofluene. As expected, lycopene was the most abundant carotenoid, ranging in concentration from 0.3 mg/100 g in vegetable beef soup to 55 mg/100 g in tomato paste. The concentration of beta-carotene ranged from 0.23 mg/100 g in tomato soup to 1.51 mg/100 g in vegetable beef soup. Lutein was found at very low concentrations (less than 0.2 mg/100 g) in all products analyzed except tomato paste, which contained 0.34 g/100 g.
Tomatoes are an integral part of diet world wide. Many population studies have established link between dietary intake of tomatoes, a major source of a carotenoid antioxidant lycopene and reduced risk of chronic diseases. This study evaluates the lycopene contents of various commonly consumed tomato products and estimates its daily intake levels. A fast and simple spectrophotometric method for routine analysis of lycopene was developed and validated against HPLC method. Lycopene content in various tomato products ranged from 42 ppm to 365 ppm. Average daily dietary lycopene intake levels were assessed by administering food frequency questionnaire and were estimated to be 25.2 mg day−1. Fresh tomatoes accounted for 50% of total lycopene intake.
A diet rich in carotenoid-containing foods is associated with a number of health benefits. Lycopene provides the familiar red color to tomato products and is one of the major carotenoids in the diet of North Americans and Europeans. Interest in lycopene is growing rapidly following the recent publication of epidemiologic studies implicating lycopene in the prevention of cardiovascular disease and cancers of the prostate or gastrointestinal tract. Lycopene has unique structural and chemical features that may contribute to specific biological properties. Data concerning lycopene bioavailability, tissue distribution, metabolism, excretion, and biological actions in experimental animals and humans are beginning to accumulate although much additional research is necessary. This review will summarize our knowledge in these areas as well as the associations between lycopene consumption and human health.
Lycopene content up to 520 μgg−1 was measured in a number of tomato-based foodstuffs and meals. (all-E)-Lycopene was the predominant geometrical isomer but varied from 96% to 35% of total lycopene. (5Z)-Lycopene ranged from 4% to 27%. The proportion of (9Z)-lycopene fluctuated between < 1% and 14%. (13Z)-Lycopene and (15Z)-lycopene ranged (together) from < 1% to 7% and the sum of the other (Z)-isomers varied between < 1 % and 22% of total lycopene. It was shown that, during preparation of meals, lycopene undergoes ()-isomerisation, increasing the portion of (Z)-isomers.Compared to food, in human blood plasma the isomeric ratio of lycopene was found to be shifted in favour of the (Z)-isomer fraction, with (5Z)-lycopene as the predominant non-(all-E) component.