Nutritional composition and antioxidant activity of four tomato (Lycopersicon esculentum L.) farmer varieties in Northern Portugal homegardens
ABSTRACT The nutritional and antioxidant composition of four tomato Portuguese farmer' varieties widely cultivated in homegardens was determined. The analysed components included macronutrients, individual profiles of sugars and fatty acids by chromatographic techniques, hydrophilic antioxidants such as vitamin C, phenolics, flavonols and anthocyanins, and lipophilic antioxidants such as tocopherols, β-carotene and lycopene. Furthermore, the antioxidant activity was evaluated through DPPH scavenging activity, reducing power, β-carotene bleaching inhibition and TBARS formation inhibition. One of the four varieties, which is locally known as round tomato or potato tomato, proved to be the most powerful in antioxidant activity (EC50 values≤1.63 mg/ml), phenolic compounds (phenolics 31.23 mg ClAE/g extract, flavonols 6.36 mg QE/g extract and anthocyanins 3.45 mg ME/g extract) and carotenoids (β-carotene 0.51 mg/100 g and lycopene 9.49 mg/100 g), while the so-called yellow tomato variety revealed interesting nutritional composition, including higher fructose (3.42 g/100 g), glucose (3.18 g/100 g), α-linolenic acid (15.53%) and total tocopherols (1.44 mg/100 g) levels. Overall, these farmer' varieties of garden tomato cultivated in the Northeastern Portuguese region could contribute as sources of important antioxidants related to the prevention of chronic diseases associated to oxidative stress, such as cancer and coronary artery disease.
Full-textDOI: · Available from: José Pinela, Nov 25, 2014
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- "values such as carbohydrates and antioxidants, as presented in the study performed by Pinela et al. (2012) for four different Portuguese tomatoes. Branthome (2010) reported that around 70% of the total production, representing more than a hundred million tons of tomatoes is consumed in its fresh state and 30% (more than 48 million tons) after processing. "
ABSTRACT: The behavior of peeled and unpeeled cherry tomatoes was investigated during forced convective drying. The study showed that the drying process highly alters the shape of the samples. This alteration (shrinkage) was examined using a non-destructive X-ray microtomography imaging technique. For both cases (peeled and unpeeled tomatoes), the volume of the sample decreased linearly with its moisture content. Furthermore, the effects of the operating air temperature as well as the peel on the drying curves were explored. Accordingly, increasing the air temperature deceased drying time from 1200 ks at 50°C to 500 ks at 70°C for the unpeeled sample and from 80 ks at 60°C to 50 ks at 70°C for the peeled sample. The effect of the peel was substantial as the drying time of the unpeeled sample was five to ten times higher than that of the peeled sample. Based on the analytical solution of the diffusion model, a moisture diffusion coefficient was determined using two approaches. The first approach used a graphical representation and the moisture diffusion coefficient was directly deduced from the trend line of the curves. For the second approach, a correction factor was introduced into the analytical solution and the modeling results showed that the moisture diffusion coefficient was varying with the moisture content of the tested material. The comparison between the experimental data and the modeling results using the two approaches showed that the second approach, which included the effect of shrinkage, was more suitable for predicting the variations of the drying curves for the different operating conditions and for both peeled and unpeeled tomatoes. Using this second approach, the moisture diffusion coefficient for the unpeeled tomato was 2.0×10-11 m2/s at 50°C and 3.5×10-11 m2/s at 70°C. Similarly, the maximum values of the moisture diffusion coefficient for the peeled tomato varied from 3.0×10-10 m2/s at 50°C to 5.0×10-10 m2/s at 70°C. Moreover, performing modeling while neglecting shrinkage resulted in an over estimation of the moisture diffusion coefficient. In addition, operating conditions, dimensions of the samples and shrinkage had a direct effect on the external mass transfer coefficient.Food and Bioproducts Processing 04/2015; 94:114-123. DOI:10.1016/j.fbp.2015.02.006 · 2.47 Impact Factor
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- "Tomatoes are a very good source of antioxidants, vitamins C carotenoids (lycopene and βcarotene ) and phenolic compounds (Ilahy et al., 2011; Pinela et al., 2012). Organically grown fruits and vegetables have high levels of vitamin C, iron, magnesium, phosphorus and antioxidant activity (SOD, GR, APO, PO, phenols) and less lipid peroxidation level than conventional grown products (Worthington, 2001; Barron, 2010; Montalba et al., 2010). "
ABSTRACT: Nutrient management practices play a significant role in improving the nutritional quality of tomato. The present study deals with the evaluation of compost prepared using Effective microorganisms (EM), on antioxidant and defense enzyme activities of Tomato (Lycopersicon esculentum). A field experiment with five treatments (control, chemical fertilizer and EM compost alone and in combination) was conducted in randomized block design. An increment of 31.83% in tomato yield was recorded with the combined use of EM compost and half recommended dose of chemical fertilizers (N50P30K25 + EM compost at the rate of 5 t ha-1). Similarly, fruit quality was improved in terms of lycopene content (35.52%), antioxidant activity (24-63%) and defense enzymes activity (11-54%), in tomatoes in this treatment as compared to the application of recommended dose of fertilizers. Soil microbiological parameters also exhibited an increase of 7-31% in the enzyme activities in this treatment. Significant correlation among fruit quality parameters with soil microbiological activities reveals the positive impact of EM compost which may be adopted as an eco-friendly strategy for production of high quality edible products.Saudi Journal of Biological Sciences 11/2014; 22(3). DOI:10.1016/j.sjbs.2014.11.003 · 1.26 Impact Factor
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- "c Values without and in the parenthesis were calculated with reference to the extract and brown lead seed (dry weight), respectively J Food Sci Technol had the highest antioxidant properties (EC 50 values ≤0.15 mg/ml), whilst the sample with shade-drying had the decreases in antioxidant capacity and phenolic content (Pinela et al. 2011). The results obtained in the present study were also in accordance with Kahkonen et al. (1999) who found that total phenolic contents of vegetable extract prepared by oven drying were very low, compared with that of freeze-dried extract (P < 0.05). "
ABSTRACT: Extracts of brown lead (Leucaena leucocephala) seed prepared using different extraction solvents were determined for antioxidative activities using different assays. The highest yield (3.4–4.0%) was obtained when water was used as an extraction solvent, compared with all ethanolic extracts used (1.2–2.0 %) (P < 0.05). Much lower chlorophyll content was found in the water extract. When hot water was used, the resulting extract contained lower total phenolic and mimosine contents (P < 0.05). In general, 60–80 % ethanolic extracts had higher 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities, ferric reducing antioxidant power (FRAP) and metal chelating activity than water extracts (P < 0.05). When brown lead seed was dechlorophyllised prior to extraction, the water extract had slightly increased yield with lower chlorophyll content. Nevertheless, prior chlorophyll removal resulted in the increase in antioxidative activities but lower total phenolic and mimosine contents (P < 0.05). Generally, phenolic compounds and mimosine were more released when water was used as the extraction solvent, while the lower amount of chlorophyll was extracted. Oven-drying exhibited the negative effect on antioxidative activities and mimosine content. The higher antioxidative activities with concomitant higher total phenolic and mimosine contents were found in water extract dried by freeze drying. Thus, extraction solvent, dechlorophyllisation and drying methods directly influenced the yield and antioxidative activity of lead seed extract.Journal of Food Science and Technology -Mysore- 10/2012; 51(11). DOI:10.1007/s13197-012-0846-1 · 2.20 Impact Factor