Tài liệu Optimization of some factors influencing lycopene extraction from tomato processing waste using response surface methodology

VIETNAM NATIONAL UNIVERSITY OF AGRICULTURE NGUYEN THI KIM THANH OPTIMIZATION OF SOME FACTORS INFLUENCING LYCOPENE EXTRACTION FROM TOMATO PROCESSING WASTE USING RESPONSE SURFACE METHODOLOGY Major: Food Technology Code: 24 18 05 57 Suppevisors: 1. Assoc. Prof. Tran Thi Dinh 2. Prof. Marie-Louise Scippo AGRICULTURAL UNIVERSITY PRESS - 2017 DECLARATION I hereby declare that the data and results of research in my thesis are honest. There is no material that has been accepted for the award of any other degrees or diploma in any educational institution and, to the best of my knowledge and belief, it contains no material previously published or written by another person, except where due reference is made in the text of the thesis I hereby declare that, all the help to carry out of my thesis was thanked and the cited information in this thesis has been written clearly the source. Hanoi, May 10th, 2017 Master candidate Nguyen Thi Kim Thanh i ACKNOWLEDGEMENTS This thesis was realized at Department of Food Processing Technology and Central laboratories of Food technology-Vietnam national university of Agriculture under the supervisor of Assoc. Prof. Tran Thi Dinh and Prof. Marie-Louise Scippo. To complete this thesis, besides the effort of myself, I have received encouragement and great help of many individuals and groups. Foremost, I would like express my deep gratitude to my supervisor Assoc. Prof. Tran Thi Dinh and Prof. Marie-Louise Scippo for their valuable advices and continuous guidance, encouragement and time sharing during my study. I would like to express my sincere thanks to Msc. Nguyen Thi Hoang Lan and Dr. Hoang Hai Ha for enthusiasm, insightful comments, teaching me on the HPLC analytical technique and useful laboratory skills. I am grateful to Research and Teaching Higher Education Academy – Committee on Development Cooperation (ARES – CCD) for awarding the scholarship grant. I give my thanks to Dr. Nguyen Thi Thanh Thuy for her great support during my study. My sincere thanks are also sent to my friends especially, special thanks to my juniors Than Thi Huong, Nguyen Thi Hien and Pham Thi Bich for their assistance in the experimental work of this thesis. Last but not least, I owe more than thanks to my family, my parents, my elder sister and my younger brother for their love, support, patience and inspiration. Hanoi, May 10th, 2017 Master candidate Nguyen Thi Kim Thanh ii TABLE OF CONTENTS Declaration ......................................................................................................................... i Acknowledgements ........................................................................................................... ii Table of contents .............................................................................................................. iii List of abbreviations ......................................................................................................... v List of tables..................................................................................................................... vi List of figures .................................................................................................................. vii List of figures .................................................................................................................. vii Thesis abstract................................................................................................................ viii Chapter 1. Introduction ................................................................................................. 1 1.1. Introduction ........................................................................................................ 1 1.2. AIM .................................................................................................................... 2 1.2.1. General objective ................................................................................................ 2 1.2.2. Specific objectives ............................................................................................... 2 Chapter 2. Literature review ......................................................................................... 3 2.1. Tomato ................................................................................................................ 3 2.1.1. Origin and distribution of tomato ....................................................................... 3 2.1.2. Tomato composition ............................................................................................ 5 2.1.3. Tomato processing waste .................................................................................... 6 2.2. Lycopene ............................................................................................................ 7 2.2.1. Source of lycopene .............................................................................................. 7 2.2.2. Role of lycopene in the human health ............................................................... 10 2.2.3. Physical and chemical properties of lycopene .................................................. 11 2.3. Lycopene extraction ......................................................................................... 14 2.3.1. Solvent extraction method ................................................................................. 15 2.3.2. Other methods of lycopene extraction............................................................... 17 Chapter 3. Materials and methods .............................................................................. 20 3.1. Materials ........................................................................................................... 20 3.1.1. Sample collection and preparation .................................................................... 20 3.1.2. Equipment ......................................................................................................... 20 3.1.3. Chemical............................................................................................................ 21 iii 3.2. Research contents ............................................................................................. 21 3.3. Methodology..................................................................................................... 21 3.3.1. Experimental design .......................................................................................... 21 3.3.2. Analytical methods ............................................................................................ 25 3.3.3. Data analysis ..................................................................................................... 28 Chapter 4. Results and discussion ............................................................................... 29 4.1. Selection of the suitable organic solvent for lycopene extraction .................... 29 4.2. Selection of treatment regime of tomato waste for lycopene extraction .......... 31 4.3. Response surface methodology for optimization of lycopene extraction......... 36 Chapter 5. Conclusions and recommendations .......................................................... 42 5.1. Conclusions ...................................................................................................... 42 5.2. Recommendations ............................................................................................ 42 References ....................................................................................................................... 43 Appendix ......................................................................................................................... 48 iv LIST OF ABBREVIATIONS Abbreviation Description DPPH 1,1-diphenyl-2-picrylhydrazyl_C18H12N5O6 DW Dry weight HPLC High performance liquid chromatography w/v Weight/ volume v LIST OF TABLES Table 2.1. World tomato area, production and productivity, 2013 ............................... 3 Table 2.2. World leading tomato producing countries in the world ............................. 4 Table 2.3. Tomato area, production and productivity of some region in Viet Nam, 2009 ........................................................................................ 4 Table 2.4. Typical composition in 100 gram of a ripe tomato fruit .............................. 5 Table 2.5. Carotenoid composition of tomato fruit, tomato processing wastes and tomato paste (mg/100g wet sample) ..................................................... 7 Table 2.6. Lycopene content of common fruit and vegetables ..................................... 9 Table 2.7. Lycopene content in common tomato –based food ................................... 10 Table 2.8. Physical properties of lycopene ................................................................. 11 Table 2.9. Total lycopene and Cis-isomer content in the dehydrated tomato............. 14 Table 3.1. Effect of solvent system on lycopene extraction from tomato waste ........ 21 Table 3.2. Experimental design for drying of tomato waste ....................................... 22 Table 3.3. Box- Behnken experimental design for lycopene extraction ..................... 23 Table 4.1. Results of optimization treatment regimens for tomato waste .................. 31 Table 4.2. Summary of effect of independent factors to the output variables ............ 32 Table 4.3. Results of the analysis of variance on lycopene content ........................... 32 Table 4.4. Result of the analysis of variance antioxidant capacity of lycopene extract ......................................................................................... 34 Table 4.5. Results of optimization condition for lycopene extraction ........................ 37 Table 4.6. Summary of effect of independent factors to the output variables ............ 38 Table 4.7. Results of the analysis of variance of lycopene content ............................ 38 Table 4.8. Result of the analysis of variance of antioxidant capacity of lycopene extract ......................................................................................... 39 vi LIST OF FIGURES Figure 2.1. Structure of trans and cis isomeric forms of lycopene .............................. 13 Figure 3.1. A. Tomato ‘Chanoka F1’ fruit, B. Fresh tomato waste, C. Dried tomato waste ............................................................................... 20 Figure 3.2. HPLC chromatogram of (A) lycopene analytical standard at 0.25mg/ml and (B) CT5 sample in section 3.3.1.2 .................................... 26 Figure 3.3. HPLC calibration curve for lycopene standards dissolved in n-hexan and dichloromethane (1:1) ......................................................................... 27 Figure 3.4. Trolox calibration curve............................................................................. 28 Figure 4.1. Effect of solvents systems on lycopene concentration .............................. 29 Figure 4.2. Effect of solvents systems on antioxidant capacity of lycopene extract.... 30 Figure 4.3. Profiler showing the optimal drying conditions of tomato waste .............. 35 Figure 4.4. Profiler showing the optimal extracting conditions of lycopene extraction ................................................................................................... 40 vii THESIS ABSTRACT Master candidate: Nguyen Thi Kim Thanh Thesis title: Optimization of some factors influencing lycopene extraction from tomato processing waste using response surface methodology Major: Food technology Code: 24180557 Educational organization: Vietnam National University of Agriculture (VNUA) Research Objectives: The aim of this research is to optimize some factor (solvent/material ratio, temperature and time) influencing lycopene extraction process from tomato waste which could be used to produce functional foods. Materials and Methods: - Materials: The red ripe tomato cv. Chanoka F1 was harvested in Bac Ninh province. Tomato waste was obtained by removing the juice. Tomato paste was passed through a fruit pulper to obtain waste. Tomato waste was dried by a convective oven after that they were ground to use as material for lycopene extraction - Methods: Suitable organic solvent for lycopene extraction from tomato waste was studied ranging from single solvent (acetone, ethanol, ethyl acetate), double solvent (acetone: ethanol) and triple solvent system (acetone: ethanol: ethyl acetate). The treatment regime (moisture content and drying temperature) of tomato waste for lycopene extract also investigated. Tomato waste, which was dried in the oven at the optimal temperature and moisture content, was used to optimize of several factors (ratio of solvent/dried tomato waste, temperature, time) influencing extraction of lycopene with the most suitable solvent by response surface methodology. - Analytical methods: Moisture content of tomato waste (%) was measured using fast moisture detector (MA37, Germany). Lycopene content was quantified by HPLC. Antioxidant capacity of lycopene content was quantified by DPPH radical scavenging test. Main findings and conclusions The results of the present study indicated that ethyl acetate solvent proved to be the most efficient compared to other solvents for lycopene extraction. The optimal conditions for drying of tomato waste is temperature of 65oC until the moisture content of the material reached 23%. The optimal extraction conditions for lycopene were: + Ratio of solvent/waste 40/1 (v/w), + Temperature 55oC and viii + Extraction time 120 min. Under this optimization condition lycopene content in the extract was 7.391 mg/g DW and antioxidant capacity of extract was 10.384 µmol TE/g DW. ix CHAPTER 1. INTRODUCTION 1.1. INTRODUCTION Lycopene is one of 750 carotenoids found in nature and is responsible for the red color of fruits. It is present in high concentration in red fruit and vegetable, such as tomato, gac, carrot, watermelon… (Britton, 2004). In the food industry, lycopene is used as a natural pigment in the dyeing of food product. Besides, lycopene is also known as a potential antioxidant which is believed to be responsible for protecting cell against oxidative damage and thereby decreasing the risk of chronic diseases (Rao et al., 2006). Thus, lycopene demands on using in pharmaceutical, food, feed and cosmetic industries calls more attention nowadays. Tomato, Lycoperisicon esculentum, is one of the most widely cultivated vegetable in worldwide and known as one of fruits which are rich in lycopene. World tomato production in 2013 was about 163 million tons of fresh fruit from an estimated 4.7 million hectares (Faostat, 2014). Tomato contains a wide variety of antioxidants including vitamin E, ascorbic acid, carotenoids, flavonoids, phenolic compounds (Sathish et al., 2009). Lycopene represents about 80-90% of total carotenoids in tomato. Lycopene is located in different fractions of tomato such as tomato skin, water insoluble fraction, and fibrous fraction including fiber and soluble solids. Tomato processing industry produces large amounts of solid waste. It is about 10–40% of the total tomato processed in the facility and includes 33% seeds, 27% skin and 40% pulp (Topal et al., 2006). Toor and Savage (2005) indicated that 70–90% of the lycopene was associated with the water insoluble fraction and the skin. In Vietnam and other countries, the waste is usually used for animal feed or for organic fertilizer but it is not used for human consumption (Knoblich et al., 2005). Therefore, large quantity of carotenoids is lost as waste. In addition, this waste has a high moisture content that makes it susceptible to microbial proliferation and spoilage. Therefore, it can be preserved by drying or other methods and then for lycopene extraction. Tomato carotenoids are liposoluble. Recently, there are several methods used for lycopene extraction. Sabio et al. (2003) studied a lycopene extraction process based on supercritical CO2, which allows the extraction of over 60% of 1 the lycopene from tomato waste. Xi (2006) reported that the lycopene yield from high pressure processing treatment of tomato paste waste for 1 min was much higher than from solvent extraction for 30 min. However, lycopene is commonly extracted with organic solvents due to the cheap cost of technology and better recovery as compared to other methods. There are a lot of organic solvents, which are usually used in several studies to non-polar carotenoid extraction such as ethyl acetate, ethanol, acetone, etc. However, their parameters (solvent/material ratio, temperature and time) are largely influence on lycopene extraction. Therefore in the current study, we conduct research entitled “Optimization of some factors influencing lycopene extraction from tomato processing waste using response surface methodology”. 1.2. AIM 1.2.1. General objective The aim of this research is to optimize some factors (solvent/material ratio, temperature and time) influencing lycopene extraction process from tomato waste which could be used to produce functional foods. 1.2.2. Specific objectives - To select suitable organic solvent for lycopene extraction process from dried tomato waste; - To optimize the moisture content and drying temperature by convective drying of tomato waste for lycopene extraction; - To optimize several factors (ration of solvent/material, temperature, time) influencing on extraction of lycopene from dried tomato waste; - To characterize the extracted lycopene in term of lycopene content and anti-oxidant activity. 2 CHAPTER 2. LITERATURE REVIEW 2.1. TOMATO 2.1.1. Origin and distribution of tomato Tomato (Lycopersicon esculentum Mill.) is one of the most widely cultivated vegetable worldwide. Tomatoes are members of the family Solanaceae (also known as the nightshade family), genus Lycopersicon, subfamily Solanoideae and tribe Solanceae (Taylor, 1986). It was originated in the coastal highlands of Andean region that includes parts of Chile, Colombia, Ecuador, Bolivia and Peru (Sims, 1979). The Spanish introduced tomato into Europe in the early 16th century (Harvey et al., 2002). European acceptance of tomato as a cultivated crop and its inclusion in the cuisine were relatively slow. Tomatoes were initially grown only as ornamental plants: the fruits were considered to be poisonous, because of the closely related deadly nightshade (Solanum dulcamara). Since the mid-16th century tomatoes have been cultivated and consumed in southern Europe, though they only became widespread in northwestern Europe by the end of the 18th century (Harvey et al., 2002). In 17th century, European took the tomato to South, Southeast Asia and China. In the 18th century, tomato came to Japan and the USA. The production and consumption of tomato expanded rapidly in the USA in the 19th century, and by the end of that century, processed products such as soups, sauces and ketchup were regularly consumed (Harvey et al., 2002). Table 2.1. World tomato area, production and productivity, 2013 Location Africa America Asia Europe Ocean World Area (1000 ha) Production (1000 tons) Productivity (tons/ha) 902.16 455.84 2 821.82 500.87 7.64 4 688.34 18 118.82 24 264.84 99 205.50 20 965.20 554.36 163 108.72 20.08 53.23 35.16 41.86 72.56 34.79 Source: FAOSTAT (2014) 3 Nowadays, tomatoes become the most important vegetable in the world. According to Faostat (2014) tomato grows more than 175 countries around the world. World tomato production in 2013 was about 163 million tons of fresh fruit from an estimated 4.7 million hectares (Faostat, 2014) (Table 2.1). China leads world tomato production with about 50 million tons with 30.1% of world production followed by India with 18.2 million tons (11.1% global production) (Table 2.2). Table 2.2. World leading tomato producing countries in the world No. Country Tomato production (tons) Share of world production (%) 1 2 3 4 5 China India United States Turkey Egypt 50 552 200 18 227 000 12 574 550 11 820 000 8 533 803 30.10 11.10 7.70 7.20 5.20 Source: FAOSTAT (2014) In Vietnam, tomato was first cultivated about 100 years ago, from the French colonial period. Until now, tomato is still the main crop which prioritized for development by United State. In the 2010, tomato is estimated to be grown on more than 23,000ha with a production of nearly 460,000 tons per year (FAO, 2010). Table 2.3. Tomato area, production and productivity of some region in Viet Nam, 2009 Regions Red River Delta North Eastern North Western North Central South Central Tay Nguyen South Eastern Mekong River Delta Area (ha) Production (tons) Productivity (tons/ha) 7 828 2 670 248 1 636 1 650 4 879 1 142 3 080 172 304 33 026 3 079 13 991 18 599 145 590 10 368 52 224 22.01 14.62 12.42 8.55 11.27 29.84 9.08 16.96 Source: FAO (2010) 4 Tomatoes are mainly cultivated in the winter season. Besides, it is also grown in the summer- autumn, autumn-winter, spring-summer season on the rice land in order to bring high profit to farmers. Tomatoes are grown popularly in Red Delta region (Table 2.3), concentrated in Ha Noi, Hai Duong, Hung Yen, Bac Ninh… also in the Southern such as An Giang, Tien Giang, Lam Dong provinces…) (Dang, 2014). 2.1.2. Tomato composition Tomato is a kind of vegetable which had high nutrition value to human diet and subsequent importance in human health. They are rich in minerals, vitamines, essential amino acids, sugars and dietary fibers. Tomato contains much vitamin B and C, iron and phosphorus (Ayandiji et al., 2011). The Table 2.4 gives the main nutrients and their quantities that can be derived from consuming 100 gram of ripened tomatoes. Table 2.4. Typical composition in 100 gram of a ripe tomato fruit Nutrient Unit Amount Water Energy Fat Protein Carbohydrates Dietary fiber Potassium Phosphorus Magnesium Calcium Vitamin C Vitamin A Vitamin E Niacin β- Carotene α-carotene Lycopene G Kcal G G G G Mg Mg Mg Mg Mg IU Mg Mg µg µg µg 93.76 21.00 0.33 0.85 4.46 1.10 223.00 24.00 11.00 5.00 19.00 623.00 0.38 0.63 449.00 101.00 2573.00 Source: USDA nutrition database (2010) 5 Tomatoes are widely known for their outstanding antioxidant content, including their high concentration of lycopene and excellent amounts of other conventional antioxidants like vitamin C and tocopherols, additional carotenoid (β- carotene, lutein, and zeaxanthin) (Arab and Steck, 2000). According to Naika et al. (2005), yellow tomatoes have higher vitamin A content than red tomato, but red tomato contain lycopene, an anti-oxidant that may contribute to protection against carcinogenic substances. 2.1.3. Tomato processing waste According to FAOSTAT (2014), world tomato productions are huge about 163 million tons of fresh fruit in 2012 and on the rise in recent years. More than a third of these were used for processing industry such as juice, soup, concentrate, dry- concentrate, sauce, salsa, puree, dry-tomato, ketchup or paste (Kaur et al., 2008). Commercial processing of tomato produces large amounts of solid waste or by-products, namely tomato seeds and peels, representing 10-40% of total processed tomato (Al-Wandawi et al., 1985; Topal et al., 2006). The importance of utilization of the waste is no revenue from the sale and dumping of this processing waste at the nearest landfill site will add to the processing cost. On the other hand, if this waste remains unutilized, they not only add to the disposal problem but also aggravate environmental pollution (AlWandawi et al., 1985). These wastes can be used for animal feed. Wet tomato processing wastes can be ensiled with corn plants and the resulting silage supported good milk production (Weiss, 1997). One way of avoiding this problem would be to re-use the tomato processing wastes to take advantage of the large quantity of potentially beneficial compounds they contain. Tomato processing waste contain a variety of biologically active substances being a promising source of dietary fibers, proteins, carotenoids, tocopherols, polyphenols and other compounds (Vagi et al., 2007). Among these bioactive compound polyphenol, carotenoid and vitamins have a lot of physiological properties such as anti-inflammatory, antiallergenic, antimicrobial, anti-thrombotic, cardio-protective anti antioxidant effects (Yang et al., 2008). The results of Al-Wandawi‘s (1985) research showed that tomato skins yield about 71% of the lycopene found in tomato pastes. Finally it is clear that a large quantity of nature color is normally disposed in tomato processing “as waste” (Al-Wandawi et al., 1985). The Table 2.5 gives 6 carotenoid composition of tomato fruit, tomato processing waste and tomato paste that can be derived from consuming a 100 gram of wet sample (AlWandawi et al., 1985). Table 2.5. Carotenoid composition of tomato fruit, tomato processing wastes and tomato paste (mg/100g wet sample) Carotenoid phytoene Phytofluene β-carotene Lycopene Tomato processing wastes Whole mature fruit Tomato skin Tomato seed Tomato paste Trace Trace 0.13 3.35 Trace Trace 0.30 11.98 0 0 0 0 2.29 1.86 1.06 16.79 Source: Al-Wandawi et al. (1985) In recent years, a number of food scientists proposed that utilization of tomato processing waste can be as source of lycopene for food, in order to increase the intake of this carotenoid in the diet. Calvo et al. (2008) indicated that tomato peel could be added to dry fermented sausages to produce a meat product enriched in lycopene. Dry tomato peel was added to the meat mixture used in sausage manufacture with ratio from 0.6 to 1.2% (w/w). After 21 days ripening, lycopene level remained between 0.26 and 0.58 milligram per 100 gram of sausage (Calvo et al, 2008). Garcia et al. (2009) also indicated that the direct adding of dry tomato peel to hamburger could be useful both to obtain a new product enriched in lycopene and to provide a use for this by-product from the tomato industry. The addition of dry tomato peel to 4.5% w/w in hamburgers with good overall acceptability and a lycopene content of 4.9 mg/100 g of cook hamburger (Garcia et al. 2009). In addition, dry tomato waste is not only added to meat product (sausage, hamburger, minced meat, dry-cured, beef patties and frankfurters) but also add to bread to enrich in lycopene and other bioactive compounds (Nour et al., 2015). 2.2. LYCOPENE 2.2.1. Source of lycopene Lycopene belongs to carotenoid family that is a natural pigment synthesized exclusively by plant and microorganisms. Lycopene is a natural pigment widely used in the food industry as a food additive due to its strong color and non- 7 toxicity. It is approved for food use with registering as 160d (i) - synthetic lycopene, 160d (ii) – lycopene extract from tomato, 160d (iii) – lycopene Blakeslea trispora (tracuuphugia.vfa.gov.vn).  Chemical synthesis Synthetic lycopene is the final product of a series of reactions, starting from synthetic reagents and using chemical solvents. The final product often contains trace of chemical solvents, impurities and by-products, which could be toxic and very dangerous for health. This industrial production of synthetic lycopene has a negative environmental impact due to high amount of chemical solvents utilized (Lycopene, 2015). Synthetic lycopene is highly concentrated, it has a purity of 90-95% and it could not be directly used for human consumption. It is used for soaps, creams and cosmetics. In fact, it has a very low bio-availability and is very labile to air and light. The dietary supplements including this kind of lycopene are obtained by diluting lycopene up to 1-10% with vegetable oils, preservatives and other exogenous chemicals (Lycopene, 2015).  Biological sources Lycopene belongs to a group of naturally-occurring pigments known as carotenoids. Lycopene is a natural constituent of red fruits and vegetables and of certain algae and fungi (Olempska – Beer, 2005) Microbial source: Blakeslea trispora is a fungal plant pathogen. It is known as a source to produce lycopene and is also the microbe used for producing commercial βcarotene for dietary supplements and food additives (Wikipedia: Blakeslea trispora, 2016). Lycopene from B. trispora is produced by mating and co-fermentation of two non-pathogenic and non-toxigenic strains. Lycopene is extracted by isopropanol and isobutyl acetate from the biomass and purified by filtration and crystallization. Pure lycopene crystals are unstable when exposed to oxygen and light so lycopene is stored under nitrogen or other inert gases in light-proof containers. Olempska-Beer (2005) indicated that lycopene from B. trispora contains at least 90% of all-trans-lycopene and minor quantities of 13-cislycopene and β- and γ-carotene. 8 Plant sources: Lycopene and other carotenoid are responsible for red color of many kinds of fruit and vegetable in nature. Many fruit and vegetables are known to contain lycopene such as tomato, watermelon, pink guava, pink grapefruit, papaya, apricot and so on (Table 2.6). Table 2.6. Lycopene content of common fruit and vegetables Fruit/ vegetables Lycopene (µg/g of weight) Tomatoes Watermelon Pink guava Pink grapefruit Papaya Apricot 8.8-42.0 23.0-72.0 54.0 33.6 20.0-53.0 <0.1 Source: Rao and Agarwal (1999) Tomatoes, especially deep-red fresh tomato fruits, are considered the most important source of lycopene in many human diets (Schwartz et al., 2002). Lycopene can represent about 80-90% of total carotenoids in tomatoes. The amount of lycopene in tomato fruits depend on variety, maturity, and the environmental conditions under which the fruit matured (George, 2004). Most of lycopene compound (70-90%) is located in the insoluble fraction of the tomato such as peel. According to Al- Wandawi et al. (1985) tomato skin contains 12 mg lycopene per 100 gram skin (wet basis), while whole mature tomato contain only 3.4 mg lycopene per 100 gram (wet basis). Skin tomato is a rich source of lycopene, as they contain about five times more lycopene than the whole tomato pulp (Sharma and Le Maguer, 1996). Besides, the product was made from in tomato also contain large amount of lycopene (Table 2.7). They are also mainly source of lycopene in human diets. 9 Table 2.7. Lycopene content in common tomato –based food Tomato product Lycopene (µg/g dry matter) Fresh tomato Cooked tomato Tomato sauce Tomato paste Tomato soup (condensed) Tomato powder Tomato juice Pizza sauce Ketchup 8.8 -42.0 37.0 62.0 54.0 - 1500.0 80.0 1126.3 -1264.9 50.0 – 116.0 127.1 99.0-134.4 Source: Rao and Agarwal (1999) 2.2.2. Role of lycopene in the human health Human and animals cannot synthesize lycopene, and thus amount of lycopene in their body depends on dietary sources (Shi and Magure, 2000). Of more than 700 carotenoids in nature, there are 50 type may be absorbed and metabolized by the human body. Only 14 carotenoids have been identified in human serum, and lycopene is the most abundant (Xianquan et al., 2005). Lycopene is particularly high concentration in the prostate gland, adrenal glands, skin, liver and kidneys (Shi and Magure, 2000). Unlike other carotenoids, lycopene cannot be converted into vitamin A (Rao and Agrawal, 1999). The ability of lycopene to act as a potent antioxidant is thought to be responsible for protecting cells against oxidative damage and thereby decreasing the risk of chronic diseases (Rao and Agrawal, 1999). Several recent studies have been shown that dietary intake of tomatoes and tomato products containing lycopene associated with a decreased risk of chronic diseases (Agrawal and Rao, 2000). Dorgan et al. (1998) also indicated that serum and tissue lycopene levels have been found to be inversely related to the incidence of several types of cancer, including breast cancer and bladder cancer. Lower serum lycopene levels were found associated with increased risk and mortality from coronary heart disease (Kristenson et al., 1997). Similarly, Coodle et al. (1995) and Periquet et al. (1995) also reported that lower serum lycopene levels were in human immunodeficiency virus (HIV) positive women and also in children infected with HIV. 10