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The effects of bagging-induced light reductions on lycopene synthesis and the expression of related genes, antioxidant activity, and sugar composition of ‘Tubtim Siam’ pummelo (Citrus maxima) were investigated. Glucose, ascorbic acid, and flavonoid concentrations and 2, 2-diphenyl-1-picryhydrazyl scavenging activity were decreased in fruit covered with bags while still on the tree [0.01 μmol·m−2·s−1 photosynthetic photon flux density (PPFD)] compared with the untreated control (596.7 μmol·m−2·s−1 PPFD). The bagging treatment significantly decreased the temperatures on the surface in the bag. In addition, the bagging treatment decreased abscisic acid concentrations in the peel and pulp. However, the bagging treatment increased lycopene concentrations, upregulated phytoene synthase (CsPSY) and ζ-carotene desaturase (CsZDS) gene expressions; downregulated chromoplast-specific lycopene cyclase (CsβLCY), β-carotene hydroxylase (CsβCHX), and ε-ring hydroxylase (CsɛCHX); and decreased 9-cis-epoxycarotenoid dioxygenase (CsNCED1) gene expressions in the pulp. It is possible that maintaining a temperature of ≈25 °C in fruit covered with bags may increase the lycopene concentration in the pulp with the upregulation of CsPSY and CsZDS and the downregulation of CsβLCY, CsβCHX, CsɛCHX, and CsNCED1 gene expressions in the pulp.

Lycopene has been broadly studied in recent decades due to its health benefits including cancer prevention, anti-atherogenic and anti-obesity effects, and modulation of the immune system. To obtain efficient synthesis of lycopene, extensive researches have been conducted in various microbial cells, including Yarrowia lipolytica, to heterologously produce lycopene using various genetic and metabolic engineering methods. In this study, the effects of copy numbers of lycopene synthesis genes, a variety of key central metabolic genes (especially AMP deaminase-encoding gene AMPD), and 5-L fermenter cultivation on lycopene production in Y. lipolytica were investigated and the engineered strains with significantly enhanced lycopene content (46–60 mg/g DCW) were achieved. It is therefore possible to make use of the obtained strains to meet the industrial demand of lycopene production on the basis of further genetic and process optimization.

Fermented soybean is abundant in nutrients and bioactive ingredients. Lycopene has been reported to decrease oxidative damage, inhibit tumorigenesis, and protect cardiovascular system. In this study, three key genes (crtE, crtI, crtB) involved in lycopene synthesis were co-expressed in Bacillus amyloliquefaciens HZ-12, resulting in a lycopene producing strain HZ-12/pHYcrtEIB. This strain was used to ferment soybean, and the fermentation conditions were optimized. The highest lycopene concentration (7.3 mg/kg) was achieved at 37 °C and initial moisture content of 60%, and the lycopene endowed the red appearance for fermented soybean. Accordingly, the accumulated lycopene significantly improved the antioxidant activity of fermented soybean. Moreover, the fermented soybean showed potent anticoagulant activity, and the anticoagulant activity almost reached 100% when the concentration of soybean extract was 0.4 mg/mL. This study modified B. amyloliquefaciens to produce a novel fermented soybean food with appealing red color and multiple bioactivities, which provided a new and simple strategy for enhancing the functionality of soybean.

Lycopene is a potent antioxidant and has an anti-carcinogenic activity. However, it still remains technically challenging to formulate lipophilic lycopene as an anticancer drug. This issue was addressed by development of a bacterial carrier for targeted delivery of lycopene. First, Escherichia coli was engineered for lycopene synthesis by pathway engineering. A HER2/neu-affinity domain was subsequently displayed on the surface of the lycopene producer, rendering the strain selectively invasive. Finally, the bacterial carrier was fabricated by permeabilizing the constructed strain to facilitate release of the lycopene cargo. As a result of multiple infections with the bacterial carrier, the growth of HER2/neu-positive breast cancer cells was completely arrested. The result indicates that our proposed strategy is promising and may open up a new avenue of targeted cancer therapy using chemopreventive chemicals.

Grape and cherry tomatoes comprise about one quarter of retail tomato sales in the United States and are also important components in fresh-cut mixed vegetable trays. The latter require low temperatures and packaging which can produce a range of modified atmospheres (MA) to achieve 14 days of shelf-life. Postharvest handling recommendations for good tomato quality do not usually include low temperatures or MA. Storage studies were conducted to ascertain the effect of low temperatures and MA on grape tomato quality. Grape tomatoes (orange-red or more advanced color) can be stored in clamshells for up to 18 days at 5°C and still be of marketable quality if kept cold. Continuous storage at 5°C in air resulted in minimal weight loss (a significant cause of quality loss in grape tomato stored at warmer temperatures), and retention of vitamin C levels, but no lycopene synthesis, and decreased sugar concentrations. However, if fruit were transferred from 5 or 10°C to warmer temperatures (i.e., 20°C), typical chilling injury symptoms (decay, poor color formation) occurred on fruit stored at 5°C but not at 10°C. Controlled atmospheres (CA) of 3 or 10% O2 with 0, 7, 12 or 18% CO2 provided little or no benefit, but were tolerated by grape tomatoes for up to 21 days at 5°C. These results are based on evaluation of visual appearance, discoloration, decay, aroma, off-odors, flavor, and changes in concentrations of lycopene, sugars, vitamin C, ethanol and acetaldehyde. Although not ideal, near-ripe high quality grape tomatoes perform well as components of fresh-cut vegetable trays at low temperatures and under atmospheres not usually recommended for tomatoes.

Experiments were conducted to examine the individual and combined effect of two different electromagnetic energies, i.e., gamma ray viz 0.1, 0.5 and 1 kGy and static magnetic field (50 mT for 1 h) and their combination (0.5 kGy + 50 mT) on the shelf life of tomato and evaluates the biochemical attributes that influence the fruit ripening and fruit quality. Magnetic field application either alone or in combination with gamma irradiation was not effective in delaying the ripening process. Gamma ray exposed fruits at 0.5 and 1 kGy showed an extended shelf life due to delayed fruit ripening and reduced lycopene synthesis and ethylene production. Efficient ROS scavenging ability and consequent reduction in oxidative damage in the irradiated treatment may cause favorable biochemical changes to facilitate delayed ripening of the tomato fruits.

The aim of this study was to describe the physiology of fruit colour in tomato as affected by salinity and ripening on and off the plant. Chlorophyll and lycopene levels were repeatedly measured in ninety Raf tomatoes over a period of eight days using remittance spectroscopy. Fruits were subjected to three salinity levels and were measured either on or off the plant. The physiology of tomato colour was described by a kinetic model centred on the role of STAY-GREEN proteins (SGR) that was calibrated simultaneously on chlorophyll and lycopene data with a percentage variance explained for of 91%. Lycopene precursor and transcript SGR levels were estimated considerably higher for on-plant than for off-plant ripened fruits which indicates ongoing expression while attached to the plant. There is less inhibition of the lycopene precursor by SGR in on plant ripened tomatoes which results in higher maximum lycopene levels and less chlorophyll breakdown causing residual chlorophyll levels. Effects of salinity treatments on chlorophyll breakdown and lycopene synthesis are small, but higher salinity levels strongly diminish fresh weight. Ripening on and off the plant strongly affects colour physiology of tomato fruit and is described well by the proposed model.

The patterns of trisporoid synthesis in joint cultivation of Blakeslea trispora mates have been studied. The pair of the not-zygospore-forming carotenoid overproducer strains T(+) and T(−) was found to synthesize a large amount of trisporoids, which did not differ in biological activity from those in the wild type strains. While the β-carotene synthesis stimulator β-ionone increased the amount of trisporoids, the share of trisporic acids in their composition decreased considerably. The lycopene synthesis stimulator 2-amino-6-methylpyridine caused a decrease in the content of trisporoid which had no trisporic acids in their composition. Emergence of a new substance with the maximum absorption at 250 nm, which accounted for up to 45% of the sum of trisporoids, was a general regularity in the action of both stimulators. The combined action of these two effectors resulted in additional stimulation of lycopene synthesis and was accompanied by the disappearance of trisporic acids. The aggregate findings indicate that both carotenogenesis stimulators inhibit the synthesis of trisporic acids, i.e., their action is not mediated by stimulation of trisporoid synthesis.

During two seasons fruit of tomato (Lycopersicon esculentum Mill.) cv. Dominique (R593), harvested in early autumn at maturity stage turning, were subjected to different heat treatments before storage at 2 oC to evaluate progression of chilling injury and pigmentation. In the first season heat treatments in air (24 h at 38 oC, 6 h at 42 oC h) or in water (2 min at 48 oC, 2 min at 50 oC and 15 min at 40 oC) were compared with a control kept at 20 oC before storage. After 14 days at 2 oC and after additional 3 days at 20 oC, results showed significant differences in fruit pitting but other symptoms were unaffected and, overall, the best treatment (6 h at 42 oC) had only a marginal effect on inhibition of chilling injury. In the second season, heat treatments in air (6, 12, 24, 48 or 96 h at 42 oC) were compared with a control kept at 20 oC after different periods at 2 oC. Degradation of chlorophyll either during or after the heat treatments was unaffected while lycopene synthesis in relation to the control was arrested in all cases. Again, the overall effect of the heat treatments on progression of chilling injury at 2 oC was only marginal. Durante dos temporadas de estudios, frutos de tomate (Lycopersicon esculentum Mill.) cv. Dominique (R593), cosechados a inicios de otono en estado de madurez pinton, fueron sometidos a diferentes tratamientos termicos antes de su almacenamiento a 2 oC para evaluar la progresion del dano por enfriamiento y de la pigmentacion. En la primera temporada se compararon tratamientos termicos en aire (24 h a 38 oC, 6 h a 42 oC h) o en agua caliente (2 min a 48 oC, 2 min a 50 oC y 15 min a 40 oC), con un control mantenido a 20 oC antes del almacenamiento. Despues de 14 dias a 2 oC y despues de 3 dias adicionales a 20 oC, los resultados demostraron efectos significativos en el punteado de los frutos pero no en otros sintomas y, en general, el mejor tratamiento termico (6 h a 42 oC) solo demostro un efecto marginal en inhibicion del DPE. En la segunda temporada, tratamientos termicos en aire caliente (6, 12, 24, 48 o 96 h a 42 oC) fueron comparados con un control mantenido a 20 oC antes del almacenamiento. Despues de diferentes periodos a 2 oC, la degradacion de clorofila no se vio afectada mientras que la sintesis de licopeno en relacion al testigo disminuyo en todos los tratamientos. Nuevamente, el efecto general de los tratamientos termicos en la progresion del DPE a 2 oC fue solo marginal.

Tomato fruits are commercially harvested at earlier stages of ripeness for fresh market purpose. In the tropical climates like in India, when the temperature rises higher than 30 C especial, in summer, these fruits do not develop optimum red colour, remain yellow and become unmarketable. Surface colour is a major factor in marketing of fresh tomatoes (Garrett et al, 1960). Consumer preference for fresh tomatoes is highly correlated to the surface colour and firmness of tomatoes(Beattie et al, 1983, Jordan et al, 1985, Resurrecion and Shewfelt, 1985). Lycophene synthesis during ripening of tomatoes has been considered to be the principal factor in formation of surface colour (Meredith and Purcell, 1966). But the lycopene synthesis is temperature related. As reported by Koskitalo and Omrod (1972) normal ripening patterns do not occur below 12 C or above 30 C.At high temperatures, p-Carotene accumulates but lycopene synthesis is inhibited resulting in yellow fruit. The objective of this experiment was to obtain normal colour development and prolong the storage life of tomato fruits harvested at earlier stages of ripeness in summer, by storing them in the evaporative cool storage.

Fruits of the lutescent tomato genetic line were exposed to γ-radiation at different stages of maturity to determine the effect of ionizing radiation on carotenoid synthesis in the ripening fruit. Irradiation generally resulted in the inhibition of carotenogenesis. The effect was more pronounced at the higher dosage and in less mature fruit. Lycopene synthesis was inhibited more extensively than β-carotene synthesis. The total carotenoid content was also generally lower in irradiated fruits. It was proposed that the β-carotene in the tomato fruit is formed by a pathway not involving lycopene.

1. Seven different pigment strains of tomato were studied. In each type a number of excised fruits were matured at either 23.5⚬C. or 32.0⚬C. and the quantities of phytoene, phytofluene, α-carotene, β-carotene, ζ-carotene, ψ-carotene, prolycopene, δ-carotene, γ-carotene, neurosporene, and lycopene were determined. 2. With the exception of β-carotene and possibly prolycopene, production of all of the pigments and polyenes measured was reduced at 32⚬C. Some pigments appeared to be more sensitive to the higher temperature than others. Lycopene synthesis was drastically inhibited at 32⚬C. in every strain which produced this pigment. 3. Beta-carotene synthesis was not inhibited at 32⚬C. in the standard red tomato. When the pigments of this type were enhanced by the introduction of the high pigment factor (hp), the enlarged β-carotene fraction was not temperature sensitive. In the Tangerine type, where very little β-carotene is produced, no inhibition of its synthesis could be demonstrated. In these strains, β-c...

1. When excised normal red tomato fruits are ripened artificially at temperatures of 31.5⚬ or 32.5⚬ C., lycopene synthesis is inhibited, but β-carotene production appears not to be affected. This has suggested that in the tomato β-carotene is not formed from lycopene by isomerization as has been postulated. However, when strains which produce more than normal quantities of β-carotene, because they possess the gene B, are examined, it is found that a major portion of the β-carotene fraction is also temperature-sensitive. This, together with prior evidence, suggests that in strains carrying B, the action of this gene is to mediate the formation of the beta-ionone ring. 2. The quantitative data obtained from excised fruits were verified with quantitative data from fruits ripened on the vine under conditions of controlled temperature, light, and humidity.