Chemical and structural composition of black pigmented supragingival biofilm of bovines with periodontitis

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Contents lists available atScienceDirect

Food Research International

journal homepage:www.elsevier.com/locate/foodres

Chemical and nutritional characterization of raw and hydrothermal

processed jambu (Acmella oleracea (L.) R.K. Jansen)

Daniela Andrade Neves

a,⁎

, Marcio Schmiele

b

, Juliana Azevedo Lima Pallone

a

,

Eduardo Adilson Orlando

a

, Eder Müller Risso

c

, Elenice Carla Emidio Cunha

a

,

Helena Teixeira Godoy

a

a_{Department of Food Science, Faculty of Food Engineering, University of Campinas (UNICAMP), Campinas 13083-852, Brazil} b_{Institute of Science and Technology, Federal University of Jequitinhonha and Mucuri Valleys (UFVJM), Diamantina 39100-000, Brazil} c_{Department of Food and Nutrition, Faculty of Food Engineering, University of Campinas (UNICAMP), Campinas 13083-852, Brazil}

A R T I C L E I N F O Keywords: Spilanthes oleracea Composition Neglected vegetable Cooking process Nutritional value A B S T R A C T

Jambu (Acmella oleracea (L.) R.K. Jansen) is a neglected plant native to the Amazon Biome. Although it is very consumed in the north of Brazil, little is known about its chemical and nutritional composition. Thus, this study aimed to characterize jambu and to evaluate the effects of the boiling process on its chemical composition. The proximate composition, minerals, total amino acids, fatty acids levels, and phytosterols were determined. In comparison with conventional vegetables jambu presented higher levels of protein (24.01%), ash (10.92%), total fiber (62.61%) some mineral such as Ca (2551.56 mg/100 g), Mg (734 mg/100 g) and Cu (2.09 mg/100 g), and amino acids such as asparagine (32.01 mg/g), glutamic acid (28.26 mg/g), valine (14.55 mg/g) and isoleucine (14.19 mg/g). A significant reduction was observed in carbohydrates, total dietary fibers, minerals, unsaturated fatty acids, and in some amino acid levels after the boiling process, with an increase in ash content, protein, and saturated fatty acids in the heat-treated jambu. Lipids, phytosterols, and some amino acid levels were not sig-nificantly affected by the hydrothermal process. Thus, this study has shown that raw and processed jambu may be good alternatives for conventional vegetables, even with nutrients losses during boiling.

1. Introduction

Fruits and vegetables are important components of a healthy diet and are essential to prevent cardiovascular diseases, diabetes, obesity, and micronutrients deficiency. Green leaves may provide a balanced diet since they contain essential components such as minerals, vitamins and dietaryfibers (WHO, 2003). Nevertheless, only a small portion of edible plant species are the basis of the world agriculture and food security (IPGRI, 2002). In Brazil, the leafy vegetables most known and consumed include lettuce, rocket, watercress, kale, chicory, cabbage, and spinach, which are not native to this country (Kawashima & Valente Soares, 2003). Several vegetables are restricted to some re-gions, thus they are not well known and are poorly consumed. Those plants are considered neglected plants (also known as unconventional food plants) and many of them contain higher contents of minerals, fiber, and protein when compared to the conventional plants. The ne-glected plants are native to the regions in which they are consumed, thus they are adapted to the edaphoclimatic conditions and have

natural protection against the region plagues. Therefore, they require fewer pesticides and less handling during cultivation (IPGRI, 2002).

Acmella oleracea (L.) R.K. Jansen (bas. Spilanthes oleracea; sin. Spilanthes acmella var. oleracea), popularly named as jambu belongs to Asteraceae family and is native to the Amazon region. In the north of Brazil, jambu is much consumed, mainly cooked, as an ingredient in typical dishes such as duck in tucupi sauce (abrothmade by the fer-mentation of the liquid extracted from wildmanioc) and tacacá (asoup

common made with jambu,tucupianddried shrimps). Besides the cu-linary use, jambu is also used in folk medicine for the treatment of mouth, throat, and teeth diseases, rheumatism, anemia, inﬂuenza, among others, probably due to bioactive compounds such as spilanthol. However, jambu is not well known in the rest of the world (Nascimento et al., 2013).

The great majority of the studies on jambu has focused on the bioactive compound spilanthol, which presents several biological ac-tivities, such as anesthetic and anti-inﬂammatory properties (Nomura et al., 2013). However, few studies have investigated the chemical

https://doi.org/10.1016/j.foodres.2018.09.060

Received 13 March 2018; Received in revised form 30 August 2018; Accepted 26 September 2018

⁎_{Corresponding author.}

E-mail address:danielaandradeneves@gmail.com(D.A. Neves).

Available online 05 October 2018

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composition and nutritional properties of jambu. To the best of our knowledge, no study has been carried out on the eﬀect of the hydro-thermal processing of jambu, which is the most common preparation form.

The lack of studies on neglected plants shows that the potential value of these species is little explored. Therefore, chemical studies on neglected plants are important to identify those with high nutritional value, inserting them as alternatives to conventional vegetables in-creasing the availability of species contributing to food security. The increased consumption of the neglected plants can preserve the cultural and genetic diversity, and increase the income of the rural population (IPGRI, 2002). Thus, the aim of this study was to characterize the raw and processed jambu and to evaluate the eﬀect of the hydrothermal process on the jambu chemical properties.

2. Materials and methods 2.1. Chemicals and reagents

The chemicals and solvents were purchased from Synth (Diadema, Brazil). Chromatographic grade solvents were purchased from J.T. Baker (Phillipsburg, USA). HPLC grade formic acid and sodium nitrite were purchased from Merck (Darmstadt, Germany). Analytical stan-dards, pancreatin, nitric acid, phenyl isothiocyanate, boron triﬂuoride, dithiothreitol (DTT) and celite acid-washed were purchased from Sigma-Aldrich, Inc. (St. Louis, USA). 4-Dimethylaminobenzaldehyde (DAB) was purchased from Vetec (Xerém, Brazil). Water used in the experi-ment was puriﬁed in the Milli-Q system (Millipore, Darmstadt, Germany).

2.2. Samples

Jambu samples (around 7 Kg) were purchased in local markets of Belém, Pará, Brazil. For botanical identiﬁcation, a jambu portion was deposited at the herbarium of “Embrapa Amazônia Oriental”, Belém, Pará, Brazil. Jambu was collected and selected by eliminatingﬂowers, roots, and damaged leaves. Then, it was washed in running water and cooked in boiling water for 8 min (124 g jambu: 1 L water). The raw and processed jambu samples were freeze-dried (Terroni®, model LS3000), milled (Quimis, model Q-298A21), and stored in a vacuum sealed aluminum package at−18 °C until analysis.

2.3. Proximate composition

The proximate composition of raw and processed jambu was de-termined as follows: moisture, protein, ash, lipids, and total dietary fiber contents according toAOAC (2012). The moisture was determined in an oven at 105 °C until constant weight (930.04). The protein was determined by Kjeldahl method using a conversion factor of 6.25 (940.26). The ash content was determined in a muffle at 550 °C over-night (920.152). The lipid content was determined by an extraction with hexane by Soxhlet (948.22). The total fiber content was de-termined by an enzymatic method (991.43).Total carbohydrates con-tent was calculated by subtracting the protein, lipids, ash, and moisture from 100. Energy value (EV) was calculated as follows: EV (Kcal/ 100 g) = [4*([carbohydrates - total dietary fibers] + pro-teins)] + [9*(lipids)] (Petropoulos et al., 2017).

2.4. Minerals levels

The contents of Ca, Mg, Fe, Zn, K, Cu, Mg, and Na of raw and processed jambu were determined as reported by Silva, Orlando, Rebellato, and Pallone (2017). For the mineralization, sample (0.5 g) was rested overnight at room temperature in nitric acid (6 mL). Then, the tubes remained for 2 h at 100 °C in a digester block (Marconi, model 4025). After, nitric acid (2 mL) and hydrogen peroxide 30% (2 mL) was

added, and the tubes were heated at 130 °C for 2 h. The samples solu-bilization was performed in an ultrasound bath (Unique, model 14,000) for 5 min. The digested extract was mixed with 25 mL ultrapure water (Sartorius, model Arium Comfort) andﬁltered through ash-free ﬁlter paper (Nalgon, 9 cm in diameter). The samples were diluted as neces-sary to suit the linear range for each mineral. Lanthanum (1%) was added to the samples for Ca and Mg determination.

A flame atomic absorption spectrometer (FAAS) (Perkin Elmer, USA, model AAnalyst-200) equipped with deuterium lamp, for back-ground radiation correction, and hollow cathode lamp were used for the determination of Ca (422.67 nm), Mg (285.21 nm), Fe (248.33 nm), Zn (213.86 nm), K (766.49 nm), Cu (324.75 nm), Mn (279.48 nm), and Na (589.00 nm). Air-acetyleneflame at a flow rate of 10 L/h of acet-ylene and 2.5 L/h of air was used. Quantification was carried out using external standard calibration curves withfive points. The calibration curve presented R2_{higher than 0.99 and ranged of 0.25 to 3 mg/L for} Fe, 0.05 to 0.5 mg/L for Zn, 0.025 to 0.25 mg/L for Mg, 0.1 to 1.50 mg/ L for K, 0.08 to 1 mg/L for Na, 0.5 to 5 mg/L for Ca, 0.04 to 0.6 mg/L for Cu, and 0.05 to 0.6 mg/L for Mn.

2.5. Total amino acid proﬁle

The following total amino acids were determined according to

White, Hart, and Fry (1986)in raw and processed jambu: alanine, as-partic acid, glutamic acid, serine, hydroxyproline, arginine, glycine, cysteine, proline, tyrosine, valine, threonine, methionine, histidine, isoleucine, leucine, phenylalanine, tryptophan and lysine and the aminosulfonic acid taurine. Brieﬂy, the samples were subjected to acid digestion with hydrochloric acid (6 N) under vacuum at 110 °C for 24 h, and derivatization was carried out with phenylisothiocyanate.

The derivatized amino acids (phenylthiocarbamyl amino acids) were analyzed by high-performance liquid chromatography (HPLC) TSP (Thermo Separation Products), equipped with a quaternary pump (P 4000) and a UV-VIS detector (UV 2000- WATERS). For the separa-tion of the derivatized amino acids, a Kinetex C18 column, 100 mm, 4.6 mm i.d. (OOD-461-EO– Phenomenex, USA) was used. The mobile phase was pumped at 1.5 mL/min and was composed of sodium acetate buffer in triethylamine (A), and an aqueous solution containing 60% acetonitrile and 0.4 g/mL EDTA (B). The linear gradient elution was: 0–3.10 min from 100% to 86% A; 3.10–6.12 min from 86% to 56% A; 6.12–6.5 min from 56% to 0% A (held for 2.61 min); 9.11–9.2 min from 100% A, and held for 5.8 min. The chromatograms were processed at 254 nm. Then, the derivatized amino acids were identified by com-paring the retention time with the standards at the same chromato-graphic conditions. Quantification was carried out by internal stan-dardization, usingα-aminobutyric acid as an internal standard, and a seven-point calibration curve ranging from 0.006 to 99.99 g/100 g. The calibration curves presented R2_{higher than 0.99.}

Tryptophan was determined by a colorimetric analysis according to

Spies (1967). Brieﬂy, raw and processed jambu were digested with a

pancreatin solution (pH 7.5) at 40 °C for 24 h. Then, the extract reacted with a DAB solution for 6 h at room temperature. The extracts were derivatized with a sodium nitrite solution (0.045%), and the absor-bance was measured at 545 nm in a spectrophotometer (Becker Coulter, DU 640) after 30 min. Quantiﬁcation was carried out using a trypto-phan calibration curve ranging from 0.05 to 99.99 g/100 g. The cali-bration curve presented R2higher than 0.99.

2.6. Fatty acid proﬁle

For the determination of fatty acid proﬁle in raw and processed jambu, lipids were extracted according to Bligh and Dyer (1959). Brieﬂy, 6 g of sample were extracted with chloroform: methanol: water (1: 2: 0.8). Then, 20 mL of chloroform and 20 mL of a sodium sulfate anhydrous (1.5%) were added. The extract obtained was dried at 40 °C in a rotary evaporator (Fisatom, model 801) until solvent dried

D.A. Neves et al. Food Research International 116 (2019) 1144–1152

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completely.

Afterward, the lipids obtained were esterified as reported byJoseph and Ackman (1992). Briefly, the extracted fat (25 mg), sodium hydro-xide (0.5 M in methanol) and 5 mg of C23:0(IS) were heated at 100 °C for 20 min. After, the extract was derivatized with boron trifluoride solution (12% in methanol) at 100 °C for 5 min, and saturated sodium chloride solution was added. Then, two consecutive partition steps were performed with hexane. Finally, the upper layers were dried under nitrogenflow, re-dissolved in hexane, and stored at −80 °C until ana-lysis.

The chromatographic conditions were based onJoseph and Ackman (1992). The separation of methyl esters was performed in a 7890A gas chromatograph (GC - Agilent, Germany) equipped with aflame ioni-zation detector (FID). The methyl esters were separated using a DB 23 capillary column (60 m, 0.25 mm d.i., 0.25μm film thickness, Agilent, USA). An aliquot of the extract (1 uL) was injected at a 1:50 split ratio. The injector and detector temperatures were maintained at 250 °C and 280 °C, respectively. The oven temperature ramp was 50 °C (1 min, hold time), increasing to 175 °C at a 25 °C/min,finally to 230 °C at 4 °C/min and held for 25 min. Theflow rate of the carrier gas (He), make-up gas (N2),flame gases H2 and synthetic air were 1 mL/min, 30 mL/min, 30 mL/min, and 300 mL/min, respectively. The methyl esters were identified by comparing their retention times with those obtained with standards (FAME mix C4-C24) under the same chromatographic con-ditions. Quantification was carried out by internal standardization, using C23:0 as an internal standard. The FAME mix C4-C24 was in-jected ten times.

The correction factors (FEC) and the fatty acid concentration (mg/g lipids) were calculated according to the Eqs.(1), (2), and (3)(Joseph & Ackman, 1992), where: = F A W A . . W EC p x x p (1) = FA A W F A W F . . . . x p EC p x CAE (2) = F Molecularweight Molecularweight CAE

fatty acid methyl esters

fatty acid (3)

Apis the internal standard area, Wpis the internal standard weight, Wxis the fatty acid methyl esters weight, Axis fatty acid methyl esters area. FA is the fatty acid concentration in mg/g lipids, Axis fatty acid methyl esters area, Wpis internal standard weight, FECis the experi-mental correction factors, Apis internal standard area, Wxis the fatty acid methyl esters weight, and FCAEis the correction factor for the conversion of fatty acid methyl esters into fatty acids.

2.7. Phytosterols levels

The contents of brassicasterol, campesterol, stigmasterol, β-sitos-terol, and stigmastanol in raw and processed jambu were determined according toMäättä et al. (1999). First, the lipids were extracted ac-cording toBligh and Dyer (1959). Then, lipids were dissolved in 3% KOH (10 mL) in methanol and rested for 3 h at 50 °C. Next, deionized water (10 mL) was added, and three consecutive partitions were per-formed with hexane. The upper layer was dried at 40 °C in a rotary evaporator and re-dissolved in isopropanol. Finally, 1μL of the extract was injected into the GC-FID at a 1:50 split ratio.

Phytosterols were separated in an HP-5 capillary column with 5% phenyl-methylpolysiloxane (30 m, 0.25 mm d.i., 0.25μm film thickness, Agilent, USA). The column temperature was 150 °C for 0.1 min, in-creasing to 300 °C at 20 °C/min and held for 23 min. The injector and detector temperatures were 250 °C and 300 °C, respectively. Theflow rate of the carrier gas (He), make-up gas (N2), flame gases H2and synthetic air were 1 mL/min, 30 mL/min, 30 mL/min, and 300 mL/min, respectively. The compounds were identified by comparing the

retention time with the standard at the same chromatographic condi-tions. Quantiﬁcation was carried out using a seven-point calibration curve ranging from 20 to 100μg/mL.

2.8. Statistical analyses

All jambu plants purchased (around 7 Kg) were mixed and three different aliquots were taken to perform each of the analyzes, therefore all analyses were carried out in triplicate. Statistical analyses were performed using the Shapiro-Wilk test to evaluate the data normal distribution, and the Hartley test to determine the homogeneity of variances. Then, a paired t-test at 95% of confidence level were per-formed since the objective was to investigate the significant differences between the sample before and after processing. Principal component analysis (PCA), using the software Pirouette 3.11 (InfoMetrix, USA), with cross-validation (leave-one-out), was applied to verify the che-mical components with a higher contribution in the discrimination of the samples. The data were autoscaled to allow an equal influence in the model.

3. Results and discussion 3.1. Proximate composition

The moisture content of raw jambu of this study (Table 1) was in agreement with the results published by IBGE (1981). Lower energy value, lipids, ash, and carbohydrates contents were observed, while the protein and total dietaryfiber levels were higher when compared to data published in 1981 which presented a moisture content of 89 g/ 100 g, ashes content of 1.6 g/100 g, energy value of 32 kcal, lipid tent of 0.3 g/100 g, carbohydrates content of 1.3 g/100 g, protein con-tent of1.9 g/100 g and total dietary fiber content of1.3 g/100 g. In contrast, higher lipids and carbohydrates levels were observed when compared to those reported bySeal, Chaudhuri, and Pillai (2013)for jambu cultivated in India (lipids: 0.57% and carbohydrates: 53.83%). However, the content of moisture (87.64%), ash (12.58%), and protein (27.00%) of the jambu analyzed in India was similar to the levels found in the present study. These differences may be due to the edaphocli-matic conditions and agronomic practice in which the plants may have been cultivated (Kawashima & Valente Soares, 2003).

The Brazilian Food Composition Table (NEPA, 2011) is re-commended by Food and Agriculture Organization of the United Na-tions (FAO). According to this table, the protein content of raw jambu found in this study (Table 1) is higher when compared to some con-ventional plants such as cabbage,red leaf lettuce, crispy lettuces, chard, butterhead lettuce, rocket, red cabbage, and spinach (ranging from 0.9 to 2.0 g/100 g in wet basis). In contrast, lower protein contents were found when compared to watercress and kale, and some neglected crops such as Ocimum basilicum (alfavaca), Xanthosoma sagittifolium (taioba), and Pereskia aculeate (ora pro nobis) (rangin g from 2.7 to 3.1 g/100 g in wet basis)(NEPA, 2011; Takeiti, Antonio, Motta, Collares-Queiroz, & Park, 2009).

Although the lipids content of jambu was similar to the content of conventional vegetables, which varies from 0.1 to 0.2 g/100 g in wet basis, it was lower than those found in neglected plants such as Pereskia aculeata, Ocimum basilicum, and Xanthosoma sagittifolium (ranging from 0.4 to 0.9 g/ 100 g in wet basis). In addition, raw jambu showed a lower energy value when compared with other leaf vegetables (between 9 and 31 kcal)(NEPA, 2011;Takeiti et al., 2009). Higher ash contents were observed in raw jambu when compared to cabbage, red cabbage, and lettuce rocket (ranging from 0.4 to 0.7 g/100 g in wet basis), which was similar to kale, spinach, and rocket (ranging from 1.1 to 1.3 g/100 g in wet basis), and lower in neglected crops such as Ocimum basilicum, Xanthosoma sagittifolium, and Pereskia aculeata(ranging from 1.4 to 1.7 g/100 g in wet basis)(NEPA, 2011;Takeiti et al., 2009).

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were observed for both components. Higher total ﬁber levels were observed in jambu when compared to lettuce, watercress, spinach, kale, Ocimum basilicum, Xanthosoma sagittifolium, and Pereskia aculeate (ran-ging from 1.8 to 4.5 g/100 g in wet basis) (NEPA, 2011;Takeiti et al.,

2009). Spinach and Pereskia aculeate are considered vegetables with high dietaryﬁber content, and jambu can also be considered as rich in this compound.

The cooking process led to a signiﬁcant reduction (p < .05) of

Table 1

Proximate (%) and mineral (mg/100 g) composition on a dry and wet basis of raw and processed jambu (mean ± standard deviation).

Raw Jambu Processed Jambu p-value

Dry basis Wet basis Dry basis Wet basis

Energetic value (kcal/100 g) 113.36 ± 1.92 11.18 ± 0.42 149.74 ± 2.89 8.68 ± 0.70 0.007⁎

Moisture (%) 89.87 ± 0.44 94.16 ± 0.18 0.006⁎ Lipids (%) 1.54 ± 0.08 0.16 ± 0.01 1.94 ± 0.22 0.11 ± 0.02 0.193⁎ Protein (%) 24.10 ± 0.99 2.44 ± 0.12 32.77 ± 1.99 1.91 ± 0.14 0.000⁎ Ashes (%) 10.92 ± 0.10 1.11 ± 0.01 17.55 ± 0.12 1.03 ± 0.01 0.013⁎ Carbohydrates (% 63.38 ± 1.20 6.50 ± 0.62 47.88 ± 2.58 2.79 ± 0.05 0.000⁎ Totalﬁber (%) 62.61 ± 0.45 6.35 ± 0.06 47.23 ± 0.79 2.76 ± 0.05 0.004⁎ Minerals (mg/100 g) Ca 2551.56 ± 73.62 260.00 ± 7.50 2627.13 ± 17.03 153.42 ± 0.99 0.268 Mg 734.63 ± 4.65 74.86 ± 0.47 474.92 ± 12.02 27.74 ± 0.70 0.000⁎ Fe 19.05 ± 0.38 1.94 ± 0.04 9.60 ± 0.35 0.56 ± 0.02 0.001⁎ Zn 9.30 ± 0.16 0.95 ± 0.02 8.16 ± 0.06 0.48 ± 0.00 0.008⁎ K 5833.52 ± 392.71 594.44 ± 40.02 4857.52 ± 56.41 283.68 ± 3.29 0.053 Cu 2.09 ± 0.04 0.21 ± 0.00 2.12 ± 0.03 0.12 ± 0.00 0.498 Mn 10.42 ± 0.50 1.06 ± 0.05 4.10 ± 0.10 0.24 ± 0.01 0.003⁎ Na 15.94 ± 1.45 1.62 ± 0.15 32.12 ± 4.76 1.88 ± 0.28 0.020⁎

⁎ _{signiﬁcant diﬀerence (p < 0.05) between the sample (dry basis) in the same line. The statistical compasion was only done in the dry basis since the sample}

absorbs water during the boiling process, which causes the decrease in the content of the nutrient and makes it impossible to evaluate the change in the nutrient content of the plant during processing.

Table 2

Amino acids content on a dry and wet basis (mg/g protein) and in mg/g sample in raw and processed jambu (mean ± standard deviation).

Amino acids Raw Jambu Processed Jambu p-value

mg/g sample mg/g sample mg/g protein mg/g sample mg/g sample mg/g protein

(Dry basis) (Wet basis) (Dry basis) (Wet basis)

Non essential amino acids

Ala 12.13 ± 0.90 1.23 ± 0.09 56.51 ± 4.17 16.73 ± 0.38 0.98 ± 0.02 62.23 ± 1.43 0.073 Asp 32.01 ± 0.33 3.26 ± 0.03 149.13 ± 1.53 31.78 ± 0.69 1.86 ± 0.04 118.23 ± 2.57 0.001⁎ Glu 28.26 ± 0.40 2.88 ± 0.04 131.69 ± 1.88 35.06 ± 0.42 2.05 ± 0.02 130.46 ± 1.57 0.271 Ser 9.44 ± 0.17 0.96 ± 0.02 43.96 ± 0.77 11.98 ± 0.04 0.70 ± 0.00 44.58 ± 0.17 0.217 Hyp 1.36 ± 0.07 0.14 ± 0.01 6.33 ± 0.34 2.05 ± 0.07 0.12 ± 0.00 7.64 ± 0.26 0.041⁎ Tau n.d. n.d. n.d. n.d. n.d. n.d. TotalNEAA 83.2 8.47 387.63 97.61 5.7 363.15

Conditionally Essential amino acids

Arg 16.09 ± 0.70 1.64 ± 0.07 74.94 ± 3.28 20.81 ± 0.33 1.22 ± 0.02 77.41 ± 1.22 0.185 Gly 10.28 ± 0.09 1.05 ± 0.01 47.88 ± 0.43 13.61 ± 0.22 0.79 ± 0.01 50.64 ± 0.82 0.007⁎ Cys 0.73 ± 0.05 0.07 ± 0.01 3.42 ± 0.25 0.60 ± 0.01 0.04 ± 0.00 2.24 ± 0.03 0.012⁎ Por 9.70 ± 0.91 0.99 ± 0.09 45.194.25 13.37 ± 0.35 0.78 ± 0.02 49.76 ± 1.31 0.116 Tyr 7.91 ± 0.06 0.81 ± 0.01 36.87 ± 0.27 11.26 ± 0.38 0.66 ± 0.02 41.90 ± 1.41 0.024⁎ TotalCEAA 44.7 4.55 208.29 56.66 3.48 221.96

Essential amino acids

Val 14.55 ± 0.26 1.48 ± 0.03 67.78 ± 1.21 18.01 ± 0.24 1.05 ± 0.01 67.00 ± 0.89 0.306 Tre 9.68 ± 0.49 0.99 ± 0.05 45.10 ± 2.29 12.23 ± 0.26 0.71 ± 0.02 45.52 ± 0.96 0.678 Met 1.25 ± 0.16 0.13 ± 0.02 5.81 ± 0.76 1.99 ± 0.05 0.12 ± 0.00 7.39 ± 0.20 0.042⁎ His 3.64 ± 0.07 0.37 ± 0.01 16.94 ± 0.33 5.06 ± 0.09 0.30 ± 0.01 18.84 ± 0.33 0.036⁎ Ile 14.19 ± 0.39 1.44 ± 0.04 66.10 ± 1.82 18.23 ± 0.40 1.06 ± 0.02 67.83 ± 1.48 0.329 Leu 16.46 ± 0.36 1.68 ± 0.04 76.67 ± 1.69 21.73 ± 0.31 1.27 ± 0.02 80.84 ± 1.16 0.102 Phe 11.48 ± 0.15 1.17 ± 0.02 53.47 ± 0.69 14.04 ± 0.21 0.83 ± 0.01 52.350.77 0.268 Trp 1.29 ± 0.22 0.13 ± 0.02 6.03 ± 1.00 n.d. n.d. 0.009⁎ Lys 14.20 ± 0.25 1.45 ± 0.03 66.17 ± 1.16 20.22 ± 0.43 1.18 ± 0.03 75.23 ± 1.62 0.002⁎ TotalEAA 86.73 8.83 404.08 111.51 6.51 414.89 Phe + TyrPHE+TYR 19.39 1.97 90.33 25.3 1.48 94.15 Cys + MetCYS+MET 1.98 0.2 9.23 2.59 0.15 9.63 Total AAa _214.63 _21.85 ₁₀₀₀ _268.78 _15.7 ₁₀₀₀ n.d.: not detected.

⁎ _signi_{ﬁcant diﬀerence (p < 0.05) between the sample in mg/g protein in the same line.}

a _{TOTAL AA: total amino acid. Alanine (Ala), aspartic acid Asp), glutamic acid (Glu), serine (Ser), hydroxyproline (Hyp), taurine (Tau), arginine (Arg), glycine}

(Gly), cysteine (Cys), proline (Pro), tyrosine (Tyr), valine (Val), threonine (Tre), methionine (Met), histidine (His), isoleucine (Ile), leucine (Leu), phenylalanine (Phe), tryptophan (Trp) and lysine (Lys).

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carbohydrates and total ﬁber (Table 1) of jambu, probably due to leaching losses. However, the content of these components was com-parable to the ones found in raw watercress and raw spinach (NEPA, 2011). During cooking, there was also a signiﬁcant increase (p < 0.05) in moisture, protein, and ash contents. The increase in moisture was probably due to water absorption, while the higher protein and ash contents were due to carbohydrate loss during the processing, leading to the concentration of these components. After the cooking process, the proximate composition of jambu was similar to other green leaves (NEPA, 2011). Therefore, cooked jambu can also be an alternative to conventional vegetables.

Based in an adult diet of 2000 kcal and considering a portion of 80 g of jambu, according toWHO/FAO (2003)the daily value reached (VD) would be: carbohydrate 1.73% and 0.74% for raw and processed jambu, respectively; total ﬁber 20.32% and 8.83% for raw and processed jambu, respectively; lipids 0.23% and 0.16% for raw and processed jambu, respectively; and proteins 2.60% and 2.04% for raw and

processed jambu, respectively (WHO/FAO, 2003). Therefore, raw jambu presented a high content of totalﬁber, on the other hand the jambu VD of carbohydrate, lipids, and proteins are not high (lower than 5%), just as for other vegetables (Food And Drug Administration (Fda)., 2004)., Therefore, jambu is a good alternative to increase the number of ve-getables in which the food security is based.

3.2. Minerals levels

Calcium and potassium were the most abundant minerals in jambu, while the smaller content was observed for copper (Table 1). A vege-table containing high Ca may be an alternative to people with no access to milk and dairy products (Salazar, Velàsquez, Quesada, Piccinelli, & Rastrelli, 2006). Jambu is only a modest zinc source since it contains levels lower than 10 mg/kg (WHO/FAO, 2004).

Lower magnesium level was observed in raw jambu when compared to spinach (82 mg/100 g in wet basis). However, it was higher than that

Table 3

Fatty acids contents on a dry and wet basis (μg/g sample) and in mg/g lipids in raw and processed jambu (mean ± standard deviation).

Fatty acid Raw Jambu Processed Jambu p-value

μg/g sample μg/g sample mg/g lipid μg/g sample μg/g sample mg/g lipid

C12:0 10.36 ± 0.70 1.05 ± 0.07 0.63 ± 0.04 17.33 ± 0.73 1.01 ± 0.04 0.83 ± 0.03 0.010⁎ C14:0 16.23 ± 0.67 1.65 ± 0.07 0.99 ± 0.04 21.98 ± 0.93 1.28 ± 0.05 1.05 ± 0.04 0.043⁎ C16:0 937.12 ± 35.52 95.40 ± 3.62 57.20 ± 2.17 1255.18 ± 58.60 73.30 ± 3.42 60.00 ± 2.80 0.094 C18:0 55.66 ± 1.98 5.67 ± 0.20 3.40 ± 0.12 79.78 ± 2.51 4.66 ± 0.15 3.81 ± 0.12 0.000⁎ C20:0 7.05 ± 0.13 0.72 ± 0.01 0.43 ± 0.01 11.95 ± 0.61 0.70 ± 0.04 0.57 ± 0.03 0.009⁎ C22:0 18.57 ± 0.31 1.89 ± 0.03 1.13 ± 0.02 26.77 ± 1.03 1.56 ± 0.06 1.28 ± 0.05 0.051 C24:0 32.17 ± 0.46 3.28 ± 0.05 1.96 ± 0.03 43.91 ± 1.69 2.56 ± 0.10 2.10 ± 0.08 0.048⁎ TotalSFA 1077.17 109.66 65.75 1456.9 85.08 69.65 C14:1 n.d. n.d. n.d. n.d. n.d. n.d. C16:1 19.55 ± 0.90 1.99 ± 0.09 1.19 ± 0.06 22.85 ± 1.04 1.33 ± 0.06 1.09 ± 0.05 0.017⁎ C20:2 2.13 ± 0.15 0.22 ± 0.02 0.13 ± 0.01 1.9 ± 0.143 0.11 ± 0.01 0.09 ± 0.01 0.048⁎ C22:2 2.08 ± 0.08 0.21 ± 0.01 0.13 ± 0.01 2.19 ± 0.17 0.13 ± 0.01 0.10 ± 0.01 0.097 TotalMUFA 23.75 2.42 1.45 26.97 1.58 1.29 C18:1n9t 0.94 ± 0.04 0.10 ± 0.00 0.06 ± 0.00 3.03 ± 0.23 0.18 ± 0.01 0.1 ± 0.01 0.007⁎ C18:1n9c 116.57 ± 2.99 11.87 ± 0.30 7.74 ± 1.09 177.44 ± 11.44 10.36 ± 0.67 8.48 ± 0.55 0.267 C18:2n6t n.d. n.d. n.d. n.d. n.d. n.d. C18:2n6c 854.51 ± 35.16 86.99 ± 3.58 52.16 ± 2.15 810.39 ± 36.62 47.33 ± 2.14 38.74 ± 1.75 0.003⁎ C18:3n6 n.d. n.d. n.d. n.d. n.d. n.d. C18:3n3 2361.4 ± 98.513 240.39 ± 10.03 144.14 ± 6.01 1412.77 ± 71.84 82.51 ± 4.20 67.54 ± 3.43 0.001⁎ C20:1n9 3.33 ± 0.06 0.34 ± 0.01 0.20 ± 0.00 3.95 ± 0.18 0.23 ± 0.01 0.19 ± 0.01 0.082 C20:3n6 1.04 ± 0.07 0.11 ± 0.01 0.06 ± 0.00 n.d. n.d. n.d. 0.002⁎ C20:4n6 1.13 ± 0.12 0.12 ± 0.01 0.07 ± 0.01 1.96 ± 0.08 0.11 ± 0.00 0.09 ± 0.00 0.032⁎ C20:3n3 2.81 ± 0.07 0.29 ± 0.01 0.17 ± 0.00 2.07 ± 0.10 0.12 ± 0.01 0.10 ± 0.00 0.000⁎ C20:5n3 n.d. n.d. n.d. n.d. n.d. n.d. C22:1n9 n.d. n.d. n.d. n.d. n.d. n.d. C22:6n3 n.d. n.d. n.d. n.d. n.d. n.d. TotalPUFA 3340.73 336.13 204.6 2411.61 140.84 115.29 TOTALFA 4441.64 448.2 271.8 3895.49 227.5 186.22 n.d.: not detected.

⁎ _signi_{ﬁcant diﬀerence (p < 0.05) between the sample in mg/g lipids in the same line.}

Table 4

Phytosterols content on a dry and wet basis (mg/100 g sample and mg/100 g lipids) in raw and processed jambu (mean ± standard deviation).

Phytosterols Raw Jambu Processed Jambu p-value⁎

mg/100 g sample mg/100 g sample mg/g lipid mg/100 g sample mg/100 g sample mg/g lipid

Brassicasterol n.d. n.d. n.d. n.d. n.d. n.d. –

Campesterol 1.45 ± 0.13 0.15 ± 0.01 87.48 ± 8.09 1.37 ± 0.02 0.08 ± 0.00 65.61 ± 1.17 0.352

Stigmasterol 5.02 ± 0.76 0.51 ± 0.08 302.41 ± 46.06 5.62 ± 0.24 0.32 ± 0.01 265.86 ± 11.26 0.117 β-sitosterol 12.42 ± 0.54 1.26 ± 0.05 747.86 ± 32.43 13.57 ± 1.25 0.76 ± 0.07 622.08 ± 59.78 0.424

Stigmastanol n.d. n.d. n.d. n.d. n.d. n.d. –

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found in other green vegetables such as kale, cabbage, and lettuce (ranging from 6 to 35 mg/100 g in wet basis)(NEPA, 2011). The iron level of raw jambu was smaller than the level found in watercress (3.1 mg/100 g in wet basis) and higher than the values found in lettuce, kale, and spinach (ranging from 0.3 to 0.5 mg/100 g in wet basis) (NEPA, 2011). Sodium is the only mineral with lower levels in jambu when compared to the conventional vegetables such as kale, cabbage, and lettuce (ranging from 6 to 94 mg/100 g in wet basis)(NEPA, 2011). Concerning the mineral levels of jambu harvested in India, lower K (38 mg/g in dry basis), Ca (8.77 mg/g in dry basis) and Mg (0.791 mg/g in dry basis) levels, and higher Na (0.26 mg/g in dry basis), Fe (0.410 mg/g in dry basis), and Zn (0.217 mg/g in dry basis) levels were observed, when compared with jambu evaluated in the present study, with similar levels of the elements Mn (0.115 mg/g in dry basis) and Cu (0.025 mg/g in dry basis)(Seal et al., 2013).Kawashima and Valente Soares (2003)reported that this variation is probably due to the dif-ferent climate, soil and agronomic practice. Those authors investigated butter lettuce, ruccola, watercress, cabbage, and spinach, and found lower or similar K (271 to 537 mg/100 g in wet basis), Ca (47 to 127 mg/100 g in wet basis), Mg (18 to 55 mg/100 g in wet basis), Fe (0.5 to 1.1 mg/100 g in wet basis), Mn (0.2 to 1 mg/100 g in wet basis),

Cu (0.04 to 0.2 mg/100 g in wet basis), and Zn (0.3 to 0.8 mg/100 g in wet basis) levels when compared to the present results.

The samples of Xanthosoma sagittifolium studied bySefa-Dedeh and Agyir-Sackey (2004) presented lower Ca (7.7–24.3 mg/100 g in dry basis), Mg (58.9–85 mg/100 g in dry basis), K (769–1525 mg/100 g in dry basis), and Fe (2.81–3.89 mg/100 g in dry basis) and higher Na (21.1–49.1 mg/100 g in dry basis) and Zn (20.9–51.1 mg/100 g in dry basis) levels than those found in the present study. However, Pereskia aculeate showed higher Ca (3.420 mg/100 g of wet basis), Mg (1.900 mg/100 g of wet basis), Mn (46.4 mg/100 g of wet basis) and Zn (26.7 mg/100 g of wet basis) contents and lower K (1.632 mg/100 g of wet basis), Fe (14.2 mg/100 g of wet basis) and Cu (1.4 mg/100 g of wet basis) contents than the raw and processed jambu of this study (Takeiti et al., 2009). Jambu can be an eﬀective alternative to improve mineral intake, once it contained higher Ca, Zn, K, Mn, Cu, Mg and Fe contents when compared with common vegetables.

Signiﬁcant losses (p < 0.05) in Mn (60.65%), Fe (49.61%), Mg (35.35%), and Zn (12.25%) were observed after the cooking process (Table 1). According to Barciela-Alonso and Bermejo-Barrera (2015), boiling is the cooking process that causes the highest mineral loss, probably due to the mineral migration to the cooking water. On the

Fig. 1. Scores (A) and loadings (B) of principal component analysis. (B) I– Proximate composition (g/100 g dry basis); II – Minerals (mg/100 g dry basis); III – Fatty acids (mg/g lipids); IV– Amino Acids (mg/g protein); V Phytosterols (mg/g lipid). EV: Energy value, M: Moisture, L: Lipids, P: Protein, A: Ash, C: Carbohydrates, TF: Totalﬁber.

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other hand, a signiﬁcant increase (p < .05) was observed in Na level (100%), probably due to the migration of Na found in the tap water to jambu during cooking (WHO, 2011). The minerals content of the ve-getable and the percentage loss of this compounds during thermal process depend on the vegetable, cultivar, and processing conditions (Barciela-Alonso & Bermejo-Barrera, 2015). Even with a mineral loss (p < 0.05) after the cooking process, jambu still showed higher Ca, Mg, and Cu levels than the conventional vegetables, and comparable Fe, Zn, K and Mn contents with conventional green leaves (NEPA, 2011). Therefore, the consumption of processed jambu may be a good alter-native for mineral intake when compared with the conventional vege-tables.

Based in an adult diet of 2000 kcal and considering a portion of 80 g of jambu, according toWHO/FAO (2003)the daily value reached (VD) would be for Ca 20.80% and 12.27% for raw and processed jambu, respectively; Mg 23.03% and 8.54% for raw and processed jambu, spectively; Fe 11.09% and 3.20% for raw and processed jambu, spectively; Zn 10.86% and 5.49% for raw and processed jambu, re-spectively; Cu 18.67% and 10.67% for raw and processed jambu, respectively; Mn 36.87% and 8.35% for raw and processed jambu, spectively; and Na 0.05% and 0.06% for raw and processed jambu, re-spectively (WHO/FAO, 2004). Therefore, raw jambu is an interesting source of Ca, Mg, Cu and Mn, however, after the boiling process there was a big reduction on the VD of all the minerals, but most minerals VD were still higher than 5%, indicating that jambu did not preset very low amounts of minerals even after the thermal process. Nevertheless, since raw and processed jambu presents higher or equivalent content of mi-nerals than conventional vegetables it is still a good alternative mineral intake (Food And Drug Administration (Fda)., 2004).

3.3. Total amino-acid proﬁle

The total amino acids content (Table 2) was lower than the protein content inTable 1, probably due to the chlorophyll content found in jambu, which contributes to the total nitrogen determined through the Kjeldahl method used to estimate the total protein (Jackix, Monteiro, Raposo, Vanzela, & Amaya-Farfan, 2013). Almost all amino acids analyzed were detected in jambu, including all nine essential amino acids which constitute 40.41% of total amino acids. Only the amino-sulfonic acid taurine were not detected in jambu samples. The pre-dominant amino acids in jambu were aspartic acid and glutamic acid followed by arginine, and the essential amino acids leucine, valine, isoleucine, and lysine. According to Lisiewska, Kmiecik, Gębczyński,

and Sobczyńska (2011) aspartic acid and glutamic acid are also the predominant amino acids in several vegetables. Glutamic acid and as-partic acid contribute to energy production, other amino acids forma-tion, pyrimidine syntheses, transaminaforma-tion, and insulin regulaforma-tion, be-sides acting as a neurotransmitter (Murray, Granner, Mayes, & Rodwell, 2003).

Higher amino acid levels were observed in jambu when compared to purple lettuce (NEPA, 2011). Spinach presents equivalent glutamic acid (284 mg/100 g of wet basis), threonine (113 mg/100 g of wet basis), and phenylalanine (124 mg/100 g of wet basis) content to jambu, however, spinach presents lower contents of valine (139 mg/100 g of wet basis), arginine (157 mg/100 g of wet basis) and isoleucine (102 mg/100 g of wet basis)(Lisiewska et al., 2011). According to

Jackix et al. (2013), Xanthosoma sagittifolium leaves exhibited similar contents of alanine (1.51 g/100 g in dry basis), arginine (1.52 g/100 g in dry basis), serine (0.95 g/100 g in dry basis), cysteine (0.08 g/100 g in dry basis), proline (1.05 g/100 g in dry basis), methionine (0.18 g/ 100 g in dry basis), histidine (0.44 g/100 g in dry basis), lysine (1.58 g/ 100 g in dry basis), and valine (1.31 g/100 g in dry basis) to jambu, and lower content of aspartic acid (1.90 g/100 g in dry basis), glutamic acid (2.37 g/100 g in dry basis), and isoleucine (1.00 g/100 g in dry basis) levels. The Pereskia aculeate contained higher histidine (0.59 g/100 g in dry basis), leucine (2.00 g/100 g in dry basis), methionine (0.23 g/100 g

in dry basis), tyrosine (1.21 g/100 g in dry basis), cysteine (0.35 g/ 100 g in dry basis), glycine (1.31 g/100 g in dry basis), alanine (1.36 g/ 100 g in dry basis), and tryptophan (5.52 g/100 g in dry basis) levels when compared to jambu. However, the content of arginine (1.44 g/ 100 g in dry basis), isoleucine (1.07 g/100 g in dry basis), valine (1.28 g/100 g in dry basis), aspartic acid (1.71 g/100 g in dry basis) and glutamic acid (2.67 g/100 g in dry basis)was lower in ora-pro-nobis than in jambu(Takeiti et al., 2009).

No significant differences (p > 0.05) were observed for alanine, glutamic acid, serine, arginine, proline, valine, threonine, isoleucine, leucine, and phenylalanine after the boiling process (Table 2), with a significant decrease (p < 0.05) in the content of aspartic acid, cysteine, and tryptophan during cooking, due to the hydrothermal degradation, leaching, or interaction with other compounds in the plant matrix (Lisiewska et al., 2011). The content of hydroxyproline, glycine, tyr-osine, methionine, histidine, and lysine significantly increased (p < 0.05) after the boiling process. Studies have shown that the de-composition of some amino acids may increase the content of others amino acids (Ziena, Youssef, & El-Mahdy, 1991).

By dividing the amino acid content (mg/g protein) for the amino acid scoring pattern (mg/g protein) recommended by FAO/WHO (1985)it is obtained the amino acids scores. Scores lower than 1 de-termine the limiting amino acids (FAO/WHO, 1985). Raw and pro-cessed jambu contained all nine essential amino acids. However, the total sulfur amino acids (methionine and cysteine), tryptophan, and histidine were the limiting amino acids for children from 2 to 12 years, while total sulfur amino acids are the limiting amino acids for adults. Methionine and cysteine are also the limiting amino acids in spinach and kale (Lisiewska et al., 2011;Lisiewska, Kmiecik, & Korus, 2008). Therefore, since the protein contained in vegetables is not high and that jambu also presents some limiting amino acids, to achieve the amino acid requirements in human nutrition, jambu needs to be combined with other protein sources.

3.4. Fatty acid proﬁle

Twenty fatty acids were found in raw and processed jambu (Table 3). The fatty acid proﬁle of raw jambu is composed of 74% of polyunsaturated fatty acids (PUFA), 25% of saturated fatty acids (SFA), and 0.6% of monounsaturated fatty acids (MUFA). The main fatty acids in jambu are the unsaturated fatty acid, thus it can be stated that jambu is mainly composed of high-quality fatty acids.

The palmitic acid (C16) was the main SFA in jambu, while linoleic acid (C18:2n6c), linolenic acid (C18:3n3), and oleic acid (C18:1n9c) were the most abundant among the unsaturated fatty acid. The fatty acids C18:3n3 and C18:2n6c corresponded to 53% and 19% of the total fatty acids, respectively. (Murray et al., 2003). Although palmitic acid is a SFA, studies have shown its structural and functional role in preg-nancy and childhood, besides being essential for the transport and se-cretion of lipids (Agostoni, Moreno, & Shamir, 2016). Thus, even though jambu lipid content is very low to present nutritional beneﬁts when ingested in a meal, jambu oil contains an interesting lipid fraction from the nutritional point of view.

The fatty acid proﬁle of jambu changed (p < 0.05) after the cooking process. Basically, there was an increase (p < 0.05) in SFA (C12, C14, C18, C20, and C24), and a decrease (p < 0.05) in MUFA (C16:1 and C20:2) and PUFA (C18:2n6c, C18:3n3, C20:3n6, and C20:3n3) (Table 3), probably due to the oxidation of MUFAs and PUFAs (Damodaran, Parkin, & Fennema, 2008). Although a reduction (p < 0.05) was observed in fatty acids levels (MUFAs and PUFAs), the unsaturated fatty acids (62%) were still predominant in processed jambu, with the predominance of C18:3n3 and C18:2n6c, demon-strating that jambu can be nutritionally interesting after the boiling process.

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3.5. Phytosterols levels

The phytosterol β-sitosterol stood out in jambu with the highest contents, followed by stigmasterol and campesterol (Table 4). The total phytosterol levels were 18.89 mg/100 g and 20.56 mg/100 g for the raw and processed jambu, respectively. According toDamodaran et al. (2008), these three phytosterols are predominant in foods. Although the phytosterols are practically unabsorbed in the humans gut, they can inhibit the absorption of total cholesterols and LDL-cholesterol, thus decreasing the risks of cardiovascular diseases (Damodaran et al., 2008).

Kaloustian et al. (2008) have reported the predominance of β-si-tosterol in cabbage and celery. In romaine lettuce, coriander leaves, celery, spinach, and cabbage the content ofβ-sitosterol (5.4–16.7 mg/ 100 g edible portion), stigmasterol (1.2–7.9 mg/100 g edible portion), and campesterol (0.5–3.3 mg/100 g edible portion) were higher when compared with the jambu in the present study(Han, Yang, & Feng, 2008).

No significant difference (p > 0.05) was observed in phytosterols content after the boiling process performed in the present study (Table 4).Kaloustian et al. (2008) found almost no changes in β-si-tosterol, stigmasterol, and campesterol contents of cabbage and celery after 30 min of boiling. In addition, the phytosterols may also have been protected by the presence of unsaturated fatty acids, which presents a higher degree of instauration and compete with the oxygen present and is preferably oxidized (Barriuso, Astiasarán, & Ansorena, 2016).Since jambu oil content is very low, its consumption may not bring the phy-tosterols benefits. However, jambu oil contains interesting phytosterols, which can present health benefits.

3.6. Principal component analysis

The principal component analysis (PCA) was used to determine the main variables responsible for the differentiation of the chemical properties of raw and processed jambu. Fig. 1 shows the first two components of the PCA model of the chemical analyses of raw and processed jambu. Thefirst and second principal component (PC1 and PC2) explained 87.47 of the total variation. The scores plot (Fig. 1a) showed that PC1 (72.88%) was responsible for the formation of two groups, consistent with the discrimination of processed and raw jambu. A loading vector of a PCA defines the linear combination of the vari-ables of a particular component.Fig. 1b shows the loadings of the PC1 that were ranked in three ranges, taking into account the variables contribution for the PC1 formation. Variables with higher contribution are farthest from zero (Fig. 1b).

Variable loadings with opposite signs indicate that they are anti-correlated. The raw jambu replicates had negative loadings in thefirst PC, while the processed jambu replicates had positive loadings. Thus, the raw jambu replicates were positively correlated with carbohydrates, total fiber, some amino acids (tryptophan, threonine, and glutamic acid), some unsaturated fatty acids (C20:2, C22:2, C18:2n6c, C18:3n3, C20:3n3, and C20:3n6) and minerals, with the exception of Na (Fig. 1b). Likewise, the processed jambu replicates were positively correlated with energy value, moisture, ash, protein, some amino acids (lysine, arginine, cysteine, glycine, methionine, proline, and leucine), and SFA (C:12, C:18, C:20, C:22, and C:24). Lipids content, Na, most amino acids, and some fatty acids presented a medium correlation with raw and processed jambu. The phytosterols and the amino acids hy-droxyproline, tyrosine, valine and total amino acids were near zero, presenting a smaller correlation. Therefore, the PCA demonstrated that the greatest losses in jambu during boiling concerned the carbohydrates levels, total dietaryfiber, minerals, and unsaturated fatty acids. 4. Conclusion

The chemical and nutritional characterization of jambu shows that

the content of protein, ash, carbohydrates, totalﬁber, minerals, phy-tosterols and some amino acids (asparagine, valine, glutamic acid and isoleucine) levels are interesting and that even if nutrient loss during the hydrothermal process the nutrients content were still higher or si-milar to the ones of conventional vegetables. Therefore, both raw and processed jambu have proven to be good alternatives for the conven-tional vegetables even with nutrients loss after the boiling process. Thus, jambu might increase the diversity of vegetables consumed im-proving the food security.

Acknowledgment

The authors would like to thank the National Counsel of Technological and Scientiﬁc Development (CNPq, Brazil, Grant number 140470/2014-0) for the research ﬁnancial support and the Ph.D. scholarship.

References

Agostoni, C., Moreno, L., & Shamir, R. (2016). Palmitic Acid and Health: Introduction. Critical Reviews in Food Science and Nutrition, 56(12), 1941–1942.https://doi.org/10. 1080/10408398.2015.1017435.

Association of Oﬃcial Analytical Chemists (AOAC) (2012). Oﬃcial Methods of Analysis of AOAC INTERNATIONAL. Gaithersburg: AOAC.

Barciela-Alonso, C., & Bermejo-Barrera, P. (2015). Variation of food mineral content during industrial and culinary processing. In M. de la Guardia, & S. Garrigues (Eds.). Handbook of mineral elements in food (pp. 163–176). West Sussex: John Wiley & Sons. Barriuso, B., Astiasarán, I., & Ansorena, D. (2016). Unsaturated lipid matrices protect

plant sterols from degradation during heating treatment. Food Chemistry, 196, 451–458.https://doi.org/10.1016/j.foodchem.2015.09.074.

Bligh, E. G., & Dyer, W. J. (1959). A rapid method of total lipid extraction and pur-iﬁcation. Canadian Journal of Biochemistry and Physiology, 37(8), 911–917.https:// doi.org/10.1139/o59-099.

Brazilian Institute of Geography and Statistics (IBGE) (1981). The National Brazilian Food Composition Table. Rio de Janeiro: IBGE.

Damodaran, S., Parkin, K. L., & Fennema, O. R. (2008). Fennema's Food Chemistry (4 ed.). Boca Raton: CRC Press.

Food and Agriculture Organization of the United Nations and World Health Organization (FAO/WHO) (1985). Energy and protein requirements. Genebra: FAO/WHO.

Food And Drug Administration (Fda). (2004). How to undersantd and use the nutrition facts label. USA: Food and Drug Administration.

Han, J.-H., Yang, Y.-X., & Feng, M.-Y. (2008). Contents of Phytosterols in vegetables and Fruits Commonly consumed in China. Biomedical and Environmental Sciences, 21(6), 449–453.https://doi.org/10.1016/S0895-3988(09)60001-5.

International Plant Genetic Resources Institute (IPGRI) (2002). Neglected and underutilized plant species strategic action plan of the International Plant Genetic Resources Institute. Rome: IPGRI.

Jackix, E. A., Monteiro, E. B., Raposo, H. F., Vanzela, E. C., & Amaya-Farfan, J. (2013). Taioba (Xanthosoma sagittifolium) leaves: Nutrient composition and physiological eﬀects on healthy rats. Journal of Food Science, 78(12), H1929–H1934.https://doi. org/10.1111/1750-3841.12301.

Joseph, J., & Ackman, R. (1992). Capillary column gas chromatographic method for analysis of encapsulatedﬁsh oils and ﬁsh oil ethyl esters: Collaborative study. Journal of AOAC International, 75(3), 488–506.

Kaloustian, J., Alhanout, K., Amiot-Carlin, M. J., Lairon, D., Portugal, H., & Nicolay, A. (2008). Eﬀect of water cooking on free phytosterol levels in beans and vegetables. Food Chemistry, 107(4), 1379–1386.https://doi.org/10.1016/j.foodchem.2007.09. 061.

Kawashima, L. M., & Valente Soares, L. M. (2003). Mineral proﬁle of raw and cooked leafy vegetables consumed in Southern Brazil. Journal of Food Composition and Analysis, 16(5), 605–611.https://doi.org/10.1016/S0889-1575(03)00057-7.

Lisiewska, Z., Kmiecik, W., Gębczyński, P., & Sobczyńska, L. (2011). Amino acid proﬁle of raw and as-eaten products of spinach (Spinacia oleracea L.). Food Chemistry, 126(2), 460–465.https://doi.org/10.1016/j.foodchem.2010.11.015.

Lisiewska, Z., Kmiecik, W., & Korus, A. (2008). The amino acid composition of kale (Brassica oleracea L. var. acephala), fresh and after culinary and technological pro-cessing. Food Chemistry, 108(2), 642–648.https://doi.org/10.1016/j.foodchem. 2007.11.030.

Määttä, K., Lampi, A. M., Petterson, J., Fogelfors, B. M., Piironen, V., & Kamal-Eldin, A. (1999). Phytosterol content in seven oat cultivars grown at three locations in Sweden. Journal of the Science of Food and Agriculture, 79(7), 1021–1027.https://doi.org/10. 1002/(SICI)1097-0010(19990515)79:7<1021::AID-JSFA316>3.0.CO;2-E.

Murray, R. K., Granner, D. K., Mayes, P. A., & Rodwell, V. W. (2003). Harper's illustrated biochemistry. United States: Mcgraw-hill.

Nascimento, A. M., de Souza, L. M., Baggio, C. H., Werner, M. F., Maria-Ferreira, D., da Silva, L. M., ... Cipriani, T. R. (2013). Gastroprotective eﬀect and structure of a rhamnogalacturonan from Acmella oleracea. Phytochemistry, 85, 137–142.https://doi. org/10.1016/j.phytochem.2012.08.024.

NEPA (2011). The National Brazilian Food Composition Table. Campinas: NEPA-UNICAMP. Nomura, E. C. O., Rodrigues, M. R. A., da Silva, C. F., Hamm, L. A., Nascimento, A. M., de

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Souza, L. M., ... Werner, M. F. (2013). Antinociceptive eﬀects of ethanolic extract from theﬂowers of Acmella oleracea (L.) R.K. Jansen in mice. Journal of Ethnopharmacology, 150(2), 583–589.https://doi.org/10.1016/j.jep.2013.09.007. Petropoulos, S. A., Levizou, E., Ntatsi, G., Fernandes, A., Petrotos, K., Akoumianakis, K., ...

Ferreira, I. C. (2017). Salinity eﬀect on nutritional value, chemical composition and bioactive compounds content of Cichorium spinosum L. Food Chemistry, 214, 129–136.https://doi.org/10.1016/j.foodchem.2016.07.080.

Salazar, J., Velàsquez, R., Quesada, S., Piccinelli, A. L., & Rastrelli, L. (2006). Chemical composition and antinutritional factors of Lycianthes synanthera leaves (chomte). Food Chemistry, 97(2), 343–348.https://doi.org/10.1016/j.foodchem.2005.05.015. Seal, T., Chaudhuri, K., & Pillai, B. (2013). Evaluation of proximate and mineral

com-position of wild edible leaves, traditionally used by the local people of Meghalaya State in India. Asian Journal of Plant Sciences, 12, 171–175.https://doi.org/10.3923/ ajps.2013.171.175.

Sefa-Dedeh, S., & Agyir-Sackey, E. K. (2004). Chemical composition and the eﬀect of processing on oxalate content of cocoyam Xanthosoma sagittifolium and Colocasia es-culenta cormels. Food Chemistry, 85(4), 479–487. https://doi.org/10.1016/S0308-8146(02)00244-3.

Silva, J. G. S., Orlando, E. A., Rebellato, A. P., & Pallone, J. A. L. (2017). Optimization and validation of a simple method for mineral potential evaluation in citrus residue. Food Analytical Methods, 10(6), 1899–1908.https://doi.org/10.1007/s12161-016-0748-3. Spies, J. R. (1967). Determination of tryptophan in proteins. Analytical Chemistry, 39(12),

1412–1416.https://doi.org/10.1021/ac60256a004.

Takeiti, C. Y., Antonio, G. C., Motta, E. M. P., Collares-Queiroz, F. P., & Park, K. J. (2009). Nutritive evaluation of a non-conventional leafy vegetable (Pereskia aculeata Miller). International Journal of Food Sciences and Nutrition, 60(Suppl. 1), 148–160.https:// doi.org/10.1080/09637480802534509.

White, J. A., Hart, R. J., & Fry, J. C. (1986). An evaluation of the waters Pico-Tag system for the amino-acid analysis of food materials. The Journal of Automatic Chemistry, 8(4), 170–177.https://doi.org/10.1155/S1463924686000330.

World Health Organization (WHO) (2003). Fruit and vegetable promotion initiative. Geneva: WHO.

World Health Organization (WHO) (2011). Guidelines for drinking-water quality § 564. (Geneva WHO).

World Health Organization/ Food and Agricultural Organization of the United Nations (WHO/FAO) (2003). Joint WHO/FAO Expert Consultation on diet, nutrition and the prevention of chronic diseases § 160. Geneva: WHO.

World Health Organization/ Food and Agricultural Organization of the United Nations (WHO/FAO) (2004). Vitamin and mineral requirements in human nutrition § 341. Rome: World Health Organization.

Ziena, H. M., Youssef, M. M., & El-Mahdy, A. R. (1991). Amino acid composition and some antinutritional factors of cooked Faba beans (Medammis): Eﬀects of cooking temperature and time. Journal of Food Science, 56(5), 1347–1349.