bioactive compounds in lipid fractions of pumpkin (cucurbita sp) seeds for use in food

5
C: Food Chemistry Bioactive Compounds in Lipid Fractions of Pumpkin (Cucurbita sp) Seeds for Use in Food Carolina M´ edici Veronezi and Neuza Jorge Abstract: Seeds are considered to be agro-industrial residues, which can be used as source of macronutrients and/or raw material for extraction of vegetable oils, since they present great quantities of bioactive compounds. This study aimed to characterize the lipid fractions and the seeds of pumpkin (Cucurbita sp) varieties Nova Caravela, Mini Paulista, Menina Brasileira, and Moranga de Mesa aiming at using them in food. The chemical composition of the seeds was performed according to the official methods of American Oil Chemists’ Society and Association of Official Analytical Chemists. Total carotenoids and phenolic compounds were determined by spectrophotometry, while the levels of tocopherols were analyzed by high efficiency liquid chromatography. It was noted that the seeds contain high amounts of macronutrients that are essential for the functioning of the human organism. As to total carotenoids, Mini Paulista and Menina Brasileira pumpkin varieties presented significant amounts, 26.80 and 26.03 μg/g, respectively. Mini Paulista and Nova Caravela pumpkin varieties showed high amounts of total phenolic compounds in the lipid fractions and in the seeds. It was also found that γ -tocopherol is the isomer that stood out in the lipid fractions and in the seeds, mainly in Menina Brasileira. Finally, the consumption of these seeds and use of lipid fractions provide the supply of large quantities of compounds that are beneficial for health and that may be potentially used in food, besides representing an alternative to better use of agro-industrial residues. Keywords: carotenoids, Cucurbitaceae, macronutrients, phenolic compounds, tocopherols Practical Application: Bioactive compounds, besides presenting basic nutritional functions, provide metabolic and phys- iological health benefits when consumed as part of the usual diet. Therefore, there is a growing interest in vegetable oils of special composition, such as the ones extracted from fruit seeds. The seeds of Cucurbita sp are shown to be promising sources of oils, and especially the Cucurbita moschata and maxima species have not yet been fully elucidated. For this reason, it becomes important to investigate the chemical composition and lipid fractions of these seeds, aiming to use them in food. Introduction The food processing industry makes use of 40% to 50% of the fruit and considers the rest to be agro-industrial residues. Thus, greater attention has been given to the use of these residues, espe- cially the seeds, since they contribute to the formulation of new food products and help reduce environmental pollution (Schieber and others 2001). The pumpkins (Cucurbita sp) were domesticated in the New World and planted long ago by the Amerindians. Cucurbita moschata is the most important species in Tropical America, due to the area where it has expanded and its variability, and has Central America and Mexico as its center of diversity. C. maxima comes from South America, where it was cultivated in Pre-Columbian times, and is considered one of the oldest species. Both have high nutritional and agro economic value and are considered to be rich sources of nutrients that are essential to human health (Gonzaga and others 1999). MS 20111463 Submitted 10/7/2011, Accepted 2/07/2012. Authors are with the Dept. of Food Engineering and Technology, S˜ ao Paulo State Univ., S˜ ao Jos´ e do Rio Preto 15054–000, Brazil. Direct inquiries to author Jorge (E-mail: [email protected]). The seeds of pumpkins are promising sources of lipid, protein, and ash. Studies have shown that they found 31% to 39% and 24% to 42% of lipids in seeds of C. moschata and maxima pumpkin species, respectively. They are also rich in mono- and polyunsatu- rated fatty acids, and have low levels of sugars, starches, and other substances still unknown (Applequist and others 2006). The seeds of Cucurbita sp have been used for a long time in Chinese medicine, with reports on combating intestinal parasites and treating biliary vesicle and prostate problems. In addition, nongerminated seeds have hypoglycemic effect; they also act as antioxidant, anticancer, and anti-inflammatory (Adams and others 2011). Edible oils are involved in the steroid hormones formation, they are important sources of liposoluble vitamins and they present high amounts of compounds that are capable of providing health bene- fits, preventing diseases, or promoting the functioning of the body. Among these beneficial compounds, there are the carotenoids, phenolic compounds, and tocopherols (Alv´ ıdrez-Morales and others 2002). Carotenoids have pro-vitamin A activity, especially β -carotene, which presents 100% of this activity. This vitamin is essen- tial for night vision, growth, development, and maintenance of the epithelial tissue, besides having immunologic function (Mel´ endez-Mart´ ınez and others 2004). Carotenoids also present Journal of Food Science C 2012 Institute of Food Technologists R No claim to original US government works doi: 10.1111/j.1750-3841.2012.02736.x Vol. 77, Nr. 6, 2012 Journal of Food Science C653 Further reproduction without permission is prohibited

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Bioactive Compounds in Lipid Fractionsof Pumpkin (Cucurbita sp) Seeds for Use in FoodCarolina Medici Veronezi and Neuza Jorge

Abstract: Seeds are considered to be agro-industrial residues, which can be used as source of macronutrients and/or rawmaterial for extraction of vegetable oils, since they present great quantities of bioactive compounds. This study aimed tocharacterize the lipid fractions and the seeds of pumpkin (Cucurbita sp) varieties Nova Caravela, Mini Paulista, MeninaBrasileira, and Moranga de Mesa aiming at using them in food. The chemical composition of the seeds was performedaccording to the official methods of American Oil Chemists’ Society and Association of Official Analytical Chemists.Total carotenoids and phenolic compounds were determined by spectrophotometry, while the levels of tocopherols wereanalyzed by high efficiency liquid chromatography. It was noted that the seeds contain high amounts of macronutrientsthat are essential for the functioning of the human organism. As to total carotenoids, Mini Paulista and Menina Brasileirapumpkin varieties presented significant amounts, 26.80 and 26.03 μg/g, respectively. Mini Paulista and Nova Caravelapumpkin varieties showed high amounts of total phenolic compounds in the lipid fractions and in the seeds. It was alsofound that γ -tocopherol is the isomer that stood out in the lipid fractions and in the seeds, mainly in Menina Brasileira.Finally, the consumption of these seeds and use of lipid fractions provide the supply of large quantities of compoundsthat are beneficial for health and that may be potentially used in food, besides representing an alternative to better use ofagro-industrial residues.

Keywords: carotenoids, Cucurbitaceae, macronutrients, phenolic compounds, tocopherols

Practical Application: Bioactive compounds, besides presenting basic nutritional functions, provide metabolic and phys-iological health benefits when consumed as part of the usual diet. Therefore, there is a growing interest in vegetable oilsof special composition, such as the ones extracted from fruit seeds. The seeds of Cucurbita sp are shown to be promisingsources of oils, and especially the Cucurbita moschata and maxima species have not yet been fully elucidated. For this reason,it becomes important to investigate the chemical composition and lipid fractions of these seeds, aiming to use them infood.

IntroductionThe food processing industry makes use of 40% to 50% of the

fruit and considers the rest to be agro-industrial residues. Thus,greater attention has been given to the use of these residues, espe-cially the seeds, since they contribute to the formulation of newfood products and help reduce environmental pollution (Schieberand others 2001).

The pumpkins (Cucurbita sp) were domesticated in the NewWorld and planted long ago by the Amerindians. Cucurbita moschatais the most important species in Tropical America, due to thearea where it has expanded and its variability, and has CentralAmerica and Mexico as its center of diversity. C. maxima comesfrom South America, where it was cultivated in Pre-Columbiantimes, and is considered one of the oldest species. Both havehigh nutritional and agro economic value and are considered tobe rich sources of nutrients that are essential to human health(Gonzaga and others 1999).

MS 20111463 Submitted 10/7/2011, Accepted 2/07/2012. Authors are withthe Dept. of Food Engineering and Technology, Sao Paulo State Univ., SaoJose do Rio Preto 15054–000, Brazil. Direct inquiries to author Jorge (E-mail:[email protected]).

The seeds of pumpkins are promising sources of lipid, protein,and ash. Studies have shown that they found 31% to 39% and24% to 42% of lipids in seeds of C. moschata and maxima pumpkinspecies, respectively. They are also rich in mono- and polyunsatu-rated fatty acids, and have low levels of sugars, starches, and othersubstances still unknown (Applequist and others 2006).

The seeds of Cucurbita sp have been used for a long timein Chinese medicine, with reports on combating intestinalparasites and treating biliary vesicle and prostate problems.In addition, nongerminated seeds have hypoglycemic effect;they also act as antioxidant, anticancer, and anti-inflammatory(Adams and others 2011).

Edible oils are involved in the steroid hormones formation, theyare important sources of liposoluble vitamins and they present highamounts of compounds that are capable of providing health bene-fits, preventing diseases, or promoting the functioning of the body.Among these beneficial compounds, there are the carotenoids,phenolic compounds, and tocopherols (Alvıdrez-Morales andothers 2002).

Carotenoids have pro-vitamin A activity, especially β-carotene,which presents 100% of this activity. This vitamin is essen-tial for night vision, growth, development, and maintenanceof the epithelial tissue, besides having immunologic function(Melendez-Martınez and others 2004). Carotenoids also present

Journal of Food Science C© 2012 Institute of Food Technologists R©No claim to original US government worksdoi: 10.1111/j.1750-3841.2012.02736.x Vol. 77, Nr. 6, 2012 � Journal of Food Science C653Further reproduction without permission is prohibited

C:FoodChemistry

Bioactive compounds in seeds. . .

antioxidant activity, which may reduce the rates of photooxidationand low-density lipoproteins oxidation, thus, elevated relationshipbetween high carotenoid concentrations in human plasma andlower level of oxidative DNA damage is observed (Møller andLoft 2004).

Phenolic compounds have been receiving attention in recentyears due to their antioxidant activity, which inhibits lipid per-oxidation and lipoxygenase in vitro (Haslam 1996). Studies haveshown that grain roasting and vegetable whitening decreases theamount of phenolic compounds present in them, damaging theantioxidant and antidiabetic activities (Kunyanga and others 2012).

Besides carotenoids and phenolic compounds, tocopherols havea system of self-protection against oxidation, preserving the qualityof oil through donation of hydrogen to peroxide radicals, and theyalso delay the production of undesirable flavors (Henry and others1998). They are responsible for vitamin E action in vivo and actas liposoluble antioxidants; this is the only antioxidant that has theability to regenerate continuously by the action of vitamin C orof reduced glutathione (Traber 2007).

This study aimed to characterize the lipid fractions and the seedsof pumpkin (Cucurbita sp) cultivated in Brazil through chemicalcomposition and quantification of bioactive compounds, such asthe carotenoids, phenolic compounds, and levels of tocopherols,aiming at using them in food.

Materials and Methods

Preparation of the seedsSeeds of the pumpkin varieties Nova Caravela, Mini Paulista,

Menina Brasileira (Cucurbita moschata), and Moranga de Mesa(Cucurbita maxima) were used, for being the most appreciated onesby consumers.

All seeds were purchased in Sao Paulo State. Nova Caravelapumpkins were given as a courtesy by Silvana Doces company(Engenheiro Schmidt, Sao Jose do Rio Preto – SP) and the otherones were purchased from the local market. The seeds were col-lected monthly, between September 2009 and February 2010.After being extracted from the fruits, the seeds were selected andonly the ones that were completely and totally formed were used.Then, they were dried in a dark place at room temperature. In themoment of analysis and lipid fraction extraction, the seeds werecrushed in a grinder knife (Marconi MA340).

Lipid fraction extractionFor the extraction of lipid fraction from pumpkin seeds, the

method of Bligh and Dyer (1959) was used, since it is effectivein total lipids extraction, because polar and apolar classes are ex-tracted. Ten grams of seeds, previously dried, were weighed and25 mL of chloroform, 50 mL of methanol, and 10 mL of distilledwater were added. After that, they were stirred in a shaker for30 min. Then, 25 mL of chloroform and 25 mL of 1.5% sodiumsulfate solution were added. Once again, the mixture was stirredin a shaker for 2 min and transferred into a separating funnel.After separation of the phases, the lower phase was filtered in aflat-bottomed flask with filter paper containing anhydrous sodiumsulfate. The solvent was recovered in a rotary evaporator, at 40 ◦C.The oil was placed in amber glass, inerted with gaseous nitrogen,and stored at −18 ◦C until the moment of analysis.

Chemical composition of seedsThe levels of moisture, crude fat, and ash were determined ac-

cording to the official methods of American Oil Chemists’ Society

(AOCS 2009); crude protein content was determined according tothe official methods of Association of Official Analytical Chemists(AOAC 2005) and total carbohydrate content was obtained bydifference. The energy value was estimated by multiplying thepercentages of crude protein, crude fat, and carbohydrates by theirrespective Atwater factors, which are 17, 37, and 17 (FAO 2003).

Total carotenoidsFor the analysis of carotenoids, the lipid fraction was previously

saponified by the method of Rodriguez-Amaya and others (1988)to remove interfering substances, such as chlorophyll. After that,quantification was performed in a scanning spectrophotometer, ina 300 to 550 nm wavelength range, using the value A of 2592,in petroleum ether, to calculate the amount of total carotenoids,expressed as β-carotene, in micrograms per gram of oil (μg/g), ac-cording to methodology described by Rodriguez-Amaya (1999).

Total phenolic compoundsTotal phenolic compounds were extracted from the lipid frac-

tion according to the method proposed by Parry and others (2005).Quantitative analyses were performed spectrophotometrically, us-ing the Folin-Ciocalteau reagent and gallic acid standard curve,as the method described by Singleton and Rossi (1965). Thismethod is based on the reduction of phosphomolybdic and phos-photungstic acids in alkaline solution, to form a blue color com-plex. The results were expressed as milligrams of gallic acid equiv-alents per gram of oil (mg EAG/g).

Levels of tocopherolsTocopherol composition was determined by AOCS method

Ce 8–89 (2009). The analysis was performed by high-performanceliquid chromatography (HPLC) with fluorescence detection underthe following conditions: silica column 4.6 × 250 mm with pore of5 μm; as mobile phase, the mixture of n-hexane and isopropanol(99.5:0.5, v/v); flow of 1.2 mL/min, excitation wavelength of290 nm and emission wavelength of 330 nm. The quantificationof each isomer was performed by external standardization based onpeak areas, using standards of α-, β-, γ -, and δ-tocopherol, whoseresults were expressed as milligram per kilogram of oil (mg/kg).

Statistical AnalysisThe results obtained from analytical determinations, in tripli-

cate, were subjected to analysis of variance and differences betweenmeans were tested at 5% probability by Tukey’s test (Gacula andothers 2008), through the ESTAT program, version 2.0.

Results and Discussion

Chemical compositionThe results of the chemical composition of pumpkin seeds are

shown in Table 1. During drying, the rupture of cell walls occurs,due to the loss of moisture, which helps in the process of oilextraction by solvent and is of great importance for the yield. Inpractice, the seeds are dried in order to obtain humidity below10%, because the seeds with low moisture content, when stored,maintain most of their chemical and nutritional characteristicsunchanged for several months (Schwartzberg 1987).

All varieties showed high percentages of lipids (from 30.68to 42.29%), indicating that these seeds are good sources ofoil, especially when compared to other ones, such as soy-bean, which presents an average of 18% to 22% of lipid and

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Bioactive compounds in seeds. . .

is the most used seed in Brazilian production of vegetable oils(Bagger and others 1998).

The seeds also showed high ash and crude protein content:the variety Menina Brasileira stood out, with 4.53% and 34.89%,respectively. As for total carbohydrates, the values obtained rangedfrom 15.48% to 26.43%, since they are mainly connected with theamounts of lipids and crude proteins present in seeds of differentpumpkin varieties.

The energy value was calculated to determine the relationshipbetween the composition and energy available in the seeds (FAO1981). Among the seeds, the ones from Moranga de Mesa stoodout, with 2400.62 kJ/100 g, followed by Nova Caravela, MiniPaulista, and Menina Brasileira seeds.

Total carotenoidsThe results of bioactive compounds (total carotenoids, total phe-

nolic compounds, and tocopherols) in the lipid fractions and inthe pumpkin seeds are listed in Table 2.

As to total carotenoids, it can be noticed that high amountswere found in the lipid fraction as well as in the seeds fromMini Paulista pumpkin variety, followed by Menina Brasileira,Moranga de Mesa, and Nova Caravela. Parry and others (2006)obtained 70.59 μmol/kg of carotenoids studying roasted pumpkinseed oils, extracted in cold. Tuberoso and others (2007) quanti-

fied β-carotene in several conventional vegetable oils and found5.7 mg/kg in pumpkin seed oil. These authors concluded thatsuch oil serves as an important dietary source of carotenoids.

The different values of carotenoid concentration are affectedby the genotype and stage of fruit maturation, and also by theirextraction and storage conditions. Oils extracted from seeds ofmature fruits may contain higher amounts of carotenoid pigments,while those obtained from partially mature fruits present higherconcentrations of chlorophyll (Shi and others 2010).

Total phenolic compoundsLipid fractions are important sources of total phenolic com-

pounds and they are present in decreasing order in Mini Paulista(3.62 mg EAG/g), Nova Caravela (3.56 mg EAG/g), MeninaBrasileira (2.39 mg EAG/g), and Moranga de Mesa (1.35 mgEAG/g) pumpkin varieties. Regarding the seeds, the variety NovaCaravela stands out, followed by Mini Paulista, Menina Brasileira,and Moranga de Mesa. Values, lower than those above, werefound by other researchers who have analyzed the seed oils fromCucurbita pepo L. pumpkin (Andjelkovic and others 2010). Parryand others (2008) analyzed the content of total phenolic com-pounds in oil extracted from roasted pumpkin seeds (C. pepo L.),using the Folin-Ciocalteau reagent and verified the presence of1.58 mg EAG/g of these compounds.

Table 1–Chemical composition (%) of pumpkin seeds.

Varieties

Components Nova Caravela Mini Paulista Menina Brasileira Moranga de mesa

Moisture 6.80 ± 0.01b 6.04 ± 0.04c 7.38 ± 0.02a 5.16 ± 0.01d

Crude fat 40.63 ± 0.17b 33.52 ± 0.06c 30.68 ± 0.01d 42.29 ± 0.09a

Ash 4.11 ± 0.02b 4.46 ± 0.01a 4.53 ± 0.04a 3.39 ± 0.04c

Crude protein 32.98 ± 0.30b 29.56 ± 0.23c 34.89 ± 0.20a 32.09 ± 0.28b

Total carboydrates∗ 15.48 26.43 22.53 17.08Energy value∗∗ 2327.13 2192.07 2111.30 2400.62

The results represent the mean ± standard deviation of the analysis performed in triplicate.a,bMeans followed by the same letter do not differ by Tukey’s test (P < 0.05).∗Calculated by difference, ∗∗kJ/100 g.

Table 2–Bioactive compounds present in lipid fractions and seeds of pumpkin.

Varieties

Bioactive compounds Nova Caravela Mini Paulista Menina Brasileira Moranga de Mesa

Total carotenoids (μg/g)Lipid fraction 7.67 ± 1.16c 26.80 ± 0.93a 26.03 ± 1.70a 11.53 ± 1.84b

Seeds 3.12 ± 0.47c 8.98 ± 0.31a 7.99 ± 0.52a 4.88 ± 0.77b

Total phenolic compounds (mg EAG/g)Lipid fraction 3.56 ± 0.12a 3.62 ± 0.07a 2.39 ± 0.15b 1.35 ± 0.05c

Seeds 1.45 ± 0.05a 1.21 ± 0.02b 0.73 ± 0.04c 0.57 ± 0.02d

Composition tocopherols (mg/kg)α-Tocopherol

Lipid fraction 9.87 ± 0.31c 10.97 ± 0.22b 23.97 ± 0.18a 4.27 ± 0.04d

Seeds 4.01 ± 0.10b 3.68 ± 0.10c 7.35 ± 0.10a 1.81 ± 0.01d

β-TocopherolLipid fraction nd nd 2.23 ± 0.04a 1.37 ± 0.04b

Seeds nd nd 0.68 ± 0.01a 0.58 ± 0.01b

γ -TocopherolLipid fraction 225.73 ± 1.96b 36.00 ± 1.00d 352.40 ± 1.20a 144.60 ± 0.73c

Seeds 91.71 ± 0.80b 12.08 ± 0.30d 108.1 ± 0.36a 61.15 ± 0.30c

δ-TocopherolLipid fraction 8.87 ± 0.36a 7.90 ± 0.00b 7.83 ± 0.04b 7.93 ± 0.04b

Seeds 3.60 ± 0.10a 2.65 ± 0.01b 2.40 ± 0.01b 3.35 ± 0.01a

TotalsLipid fraction 244.47 ± 2.18b 54.87 ± 0.82d 386.43 ± 1.24a 158.17 ± 0.82c

Seeds 99.33 ± 0.90b 18.41 ± 0.30d 118.56 ± 0.38a 66.89 ± 0.30c

The results represent the mean ± standard deviation of the analysis performed in triplicate.a,bMeans followed by the same letter do not differ by Tukey’s test (P < 0.05).nd = not detected.

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Bioactive compounds in seeds. . .

The variation in the amount of phenolic compounds may occurdue to differences in the extraction method and solvent used, sincethe solvent polarity interferes in the type of extracted compounds,also due to the intrinsic (species) and extrinsic (environmentalconditions) factors and the treatment given to the seeds beforelipid extraction (Kalt 2001; Kunyanga and others 2012).

Levels of tocopherolsMost foods of vegetable origin contain low levels of vitamin E.

However, due to the abundance of foods derived from plants andthat constitute the diet, the ingestion of a significant amount ofthis vitamin, which is of high nutritional importance, is possible.The isomer α-tocopherol is the one that shows highest vitamin Eactivity (Schmidt and Pokorny 2005).

The amount of α-tocopherol found in lipid fraction of pump-kin seeds ranged from 4.27 to 23.97 mg/kg, while in the seeds itwas found between 1.81 to 7.35 mg/kg, showing that they con-tain considerable amounts of vitamin E. These values are similarto those observed by Ryan and others (2007) in seeds of pump-kins originated in Ireland. However, these values are lower thanthose found by Sant’Anna (2005) when she studied seeds fromthe pumpkin Cucurbita pepo grown in Santa Catarina, and higherthan those obtained by Murkovic and others (2004) when theyinvestigated some chemical changes that occurred in pumpkin (C.pepo L.) seeds, during the roasting process for obtaining oil.

The isomer β-tocopherol was not detected in the lipid fractionand in the seeds from Nova Caravela and Mini Paulista pumpkinvarieties. Stevenson and others (2007) analyzed the seed oils of12 pumpkin varieties, from C. maxima species, and also noticedthe absence of this isomer. However, Vidrih and others (2010)analyzed commercial oils of pumpkins originated in Slovenia andfound low amounts of β-tocopherol (2.90 to 5.90 mg/kg).

The isomer γ -tocopherol has great antioxidant potential, whichhelps protect the unsaturated fatty acids from lipid oxidation. Inthis study, high amounts of γ -tocopherol were found in the lipidfraction, as well as in the seeds of Menina Brasileira, followed byNova Caravela, Moranga de Mesa, and Mini Paulista pumpkinvarieties.

Parry and others (2006) obtained 216.30 mg/kg of γ -tocopherol from oils of roasted pumpkin seeds. Rafalowski andothers (2008) analyzed vegetable oils from local market in Polandand found 48.57 mg/kg of γ -tocopherol in pumpkin seed oil.Aued-Pimentel and others (2004), while studying pumpkin seedoil found values of γ -tocopherol similar to those reported in thisstudy. However, Tuberoso and others (2007) obtained lower val-ues, while examining Cucurbita pepo L seed oil. High percentageof γ -tocopherol makes pumpkin seed oil similar to others of highantioxidant potential, such as sesame, soy, and corn oils.

The isomer δ-tocopherol was found in all pumpkin varieties,and mostly in Nova Caravela, 8.87 mg/kg in total lipid fractionand 3.60 mg/kg in seeds. Stevenson and others (2007), researchingon the seed oils of 12 C. maxima pumpkin varieties, detected thepresence of high amount of δ-tocopherol (35.3 to 1109.7 mg/kg),while Vidrih and others (2010), studying commercial oil frompumpkins seeds, obtained from 7.90 to 20.9 mg/kg.

The amount of total tocopherols ranged from 54.87 to 386.43mg/kg in lipid fraction and from 18.41 to 118.56 mg/kg in seeds.Szterk and others (2010) obtained approximately 1500 mg/kg oftotal tocopherols in seed oils of pumpkins from Poland. Stevensonand others (2007) detected from 589.4 to 1234.2 mg/kg in C. max-ima seed oils. Different contents, found by different studies, mightbe related to the amount of polyunsaturated fatty acids present in

each pumpkin species and variety and also to the processing andextraction conditions (Rabascall and Riera 1987).

ConclusionThe consumption of pumpkin seeds, especially of Moranga de

Mesa, Menina Brasileira, and Mini Paulista varieties, provides thesupply of important amounts of nutrients necessary for humandiet, especially lipids, proteins, and total carbohydrates.

All lipid fractions analyzed are composed of high amounts ofbioactive compounds. Mini Paulista pumpkin variety showed tobe rich in total carotenoids and total phenolic compounds. As tothe levels of tocopherols, the lipid fraction of Menina Brasileiraseeds stood out and showed to be a good source vitamin E andantioxidant, mainly due to the amount of α- and γ -tocopherol.

Finally, it was found that the seeds, instead of being discardedand contaminating the environment, may be employed in theformulation and/or development of new food products or be usedas raw material for the extraction of special oils.

AcknowledgmentsThe National Council of Scientific and Technological Devel-

opment – CNPq, for sponsoring the research and its productivity;Foundation for the Development of UNESP – FUNDUNESP,for financial support.

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