Composition of Chilean jojoba seeds

Composition of Chilean jojoba seeds

Industrial Crops and Products 17 (2003) 177 /182 www.elsevier.com/locate/indcrop Composition of Chilean jojoba seeds Patrick Cappillino a,*, Robert ...

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Industrial Crops and Products 17 (2003) 177 /182 www.elsevier.com/locate/indcrop

Composition of Chilean jojoba seeds Patrick Cappillino a,*, Robert Kleiman a, Claudia Botti b a

International Flora Technologies Ltd., 1151 N. Fiesta Blvd., Gilbert, AZ 85233-2238, USA b Casilla 1004, Facultad de Ciencias Agrono´micas, Universidad de Chile, Santiago, Chile Received 5 June 2002; accepted 1 December 2002

Abstract Liquid wax ester extracted from the seeds of the jojoba plant (Simmondsia chinensis ) is used commercially in the cosmetics industry. For this reason, it is a potentially profitable crop for the arid regions of Chile. This study evaluates the yields, and physical and chemical properties of jojoba seeds grown experimentally in Chile, compared with literature values and commercial sources in the United States, Israel, Peru, and Argentina. Cuttings from promising jojoba plants were gathered from abandoned plantations in various arid regions of Chile and propagated for study at a Chilean research station. Seed samples originating from 17 selected clones were analyzed for oil content, weight per 1000 seeds, and protein and simmondsin contents. The seed oil was analyzed for acid value, wax ester profile, fatty acid profile and fatty alcohol profile. The Chilean seeds had physical properties similar to commercial sources and literature values. However, there were differences in the chemical composition. The molecular weights of the wax esters and their fatty acid moieties were significantly higher than the literature values and commercial seed samples. The wax ester profile of the Chilean seeds had higher C42 and lower C38 content than the commercial sources. In addition, the total simmondsins content in the Chilean seed was higher than literature values and the simmondsin content with respect to its analogs (simmondsin ferulate, demethylsimmondsin (DMS), and didemethylsimmondsin (DDMS)) was considerably lower. # 2003 Elsevier Science B.V. All rights reserved. Keywords: Jojoba; Chile; Composition; Wax ester; Simmondsin; Molecular weight

1. Introduction Jojoba has become an attractive alternative crop because of the promising commercial applications for its seed oil in cosmetics. Many countries are looking toward developing jojoba culture to solve

* Corresponding author. Tel.: /1-480-545-7000; fax: /1480-892-3000. E-mail address: [email protected] (P. Cappillino).

overproduction and low price for their food and other traditional crops (Ayerza, 1996). In the late 1970s, several attempts were made by Chilean farmers to break into the market (Botti, 1992), but because of various agricultural and economical problems, many of these plantations failed (Ayerza and Coates, 1992). A growing demand for jojoba oil production has renewed interest in establishing the jojoba crop in the arid, high-salinity soils of Chile. Ceron and Delatorre (1984) and Botti et al. (1998) indicates

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that jojoba plantations now have a better chance for economic and agricultural success. This paper evaluates the commercially relevant physical and chemical properties of seed grown experimentally in Chile. These include the molecular weight of the wax esters, fatty acids and fatty alcohols, seed oil content, weight per 1000 seeds, and the protein and simmondsin contents of the seed meal. Simmondsin is a cyanoglycoside found in jojoba seed meal, which is of particular interest because of its activity in food intake reduction in animals (International Flora Technologies and Ltd., 2001). Simmondsin content represents an important seed attribute because it provides a commercial use for the meal, which otherwise has limited value. The seed samples used for analysis include many of the same clones presented in an earlier study of the effect of water and salinity stresses on seed yield (Botti et al., 1998).

Table 1 Location of abandoned jojoba plantations Sample Number

Region

Latitude

Longitude

4.15.63 4.13.1 4.11.32 4.16.28 74 16 CN42 CA 35 CN 3 CA 20 CN 11 CA 37 CN 22 CN 14 4.8 1.2.4 3.60.21

Chaca Chaca Chaca Chaca Curacavi Curacavi H. Camarones H. Camarones H. Camarones H. Camarones H. Camarones H. Camarones H. Camarones H. Camarones Las Cardas Lluta 1 Lluta 2

178 178 178 178 338 338 308 308 308 308 308 308 308 308 308 188 188

708 708 708 708 718 718 718 718 718 718 718 718 718 718 718 708 708

50? 50? 50? 50? 23? 23? 17? 17? 17? 17? 17? 17? 17? 17? 13? 24? 24?

S S S S S S S S S S S S S S S S S

8? W 8? W 8? W 8? W 8? W 8? W 24? W 24? W 24? W 24? W 24? W 24? W 24? W 24? W 15? W 12? W 12? W

content. The seed oil was analyzed for wax ester, fatty alcohol and acid profile, and acid value. 2. Materials and methods 2.1. Jojoba seed 2.1.1. Plant source Jojoba cuttings were collected from plantations that were established 16/20 years ago and had been abandoned for several years. The plantation locations are listed in Table 1. The jojoba plants were continuously selected over 3 years based on foliage color, plant vigor, seed yield, and growth habit (erectness, shape). 2.1.2. Plant establishment The most promising clones, based on the selection criteria, were propagated by cuttings and planted at the Las Cardas Experimental Station (30813? S, 71815? W, 260 m above sea level). The climatic conditions at the research station are listed in Table 2. Six replicates of each clone were planted in random locations, with 4 m between rows and 2.5 m between plants. They were drip-irrigated at 4 l/week and fertilized with 50 g per plant of urea. Seeds from 17 clones were taken and analyzed for moisture content, weight per 1000 seeds, and oil, protein and simmondsin

2.1.3. Simmondsin Simmondsins were extracted from the defatted jojoba seed meal using methanol, after glucose was added as an internal standard. Simmondsin, simmondsin ferulate, demethylsimmondsin (DMS), and didemethylsimmondsin (DDMS) contents were determined by HPLC, using a Varian (Harbor City, CA, USA) Dynamax Microsorb 60 Table 2 Climatic conditions at the Las Cardas research station Parameter

Value

Frost-free days Summer thermic value (September /February, threshold 10 8C) Maximum temperature (January) Minimum temperature (October /March) Solar radiation (January)

355 day 1.372 8day

27 8C 18.5 8C 550 cal/cm per day Accumulated chilling hours (threshold 7 8C) 500 h Potential evapotranspiration (December / 410 mm February) Rainfall range (1992 /2002) 16 /1500 mm Rainfall average (1992 /2002) 70 mm

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˚ silica column, a Spectra-Physics (Paloalto, CA, A USA) 8800/8810 HPLC pump, a Varex (Burtonsville, MD, USA) MK III Evaporative Light Scattering Detector (ELSD), and an SRI Data Acquisition System for integration. Simmondsin samples from an interlaboratory research project on simmondsin analysis (Abbott et al., 2000) were used for verification. Values within 95% confidence of the means were obtained. The HPLC analysis consisted of a solvent gradient from 90% acetonitrile and 10% water to 94% acetonitrile and 6% water in 5 min. This ratio was then held for 15 min. The mobile phase flow rate was 1.5 ml/min. The ELSD drift tube temperature was 100 8C. Nitrogen with a head pressure of 0.55 MPa and a flow rate of 1.75 l/ min, was used as the ELSD nebulizer gas. Solvents were degassed with helium prior to and during the analysis. 2.1.4. Protein Protein content of the defatted seed meal was determined from the nitrogen content using AOAC method 984.13 (AOAC, 1990) and is reported as percent of dehulled, whole seed. 2.2. Jojoba seed oil 2.2.1. Moisture and volatile matter, oil content, acid value The seed was ground and passed through a 1000 m sieve. Seed moisture and volatile matter were determined using AOCS method Ba 2a-38 (American Oil Chemists’ Society, 1998). The oil was extracted for 16 h with hexane with a Soxhlet apparatus. The extracted oil and defatted meal were used in subsequent analyses. Acid value was determined with the AOCS method Ci 4-91 (American Oil Chemists’ Society, 1998). 2.2.2. Chemical composition Methyl esters were prepared by reacting the extracted jojoba oil with methanolic sodium methoxide and extracting the esters and alcohols from the aqueous phase with hexane. Wax ester, fatty acid and fatty alcohol composition were determined with a Hewlett Packard (Avondale, PA, USA) HP 5890A gas chromato-

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Table 3 Properties of experimental jojoba seed and literature and commercial values Chilean

Oil content, db(%) Moisture (%) Weight per 1000 (g) Acid value Crude protein (%) C42 content (%) C38 content (%) Wax ester MW (amu) Fatty acid MW (amu) Fatty alcohol MW (amu)

Wisniak (1987)

53.29/2.1 53.8 2.99/0.4 4.3 951.09/120 / 0.129/0.08 B/2 15.29/1.8 14.9 56.49/2.4 50.0 4.69/1.2 6.8 610.39/2.7 606

Commercial

52.89/2.9 3.69/0.9 / 0.489/0.03 / 52.39/2.4 6.09/0.9 608.09/1.5

312.89/1.3

311.1

/

313.79/2.4

314.0

/

graph, using split injection and a flame ionization detector. The detector output was digitized and integrated by an SRI (Torrance, CA, USA) Model 203 data system. A Hewlett Packard HP 7673A automatic sampler was used to inject samples to determine the wax ester profile. A Quadrex (New Haven, CT, USA) 25 m, bonded methyl, 5% phenyl silicone column, temperature programmed from 240 to 320 8C at 10 8C/min was used. Fatty acid (as methyl esters) and alcohol profiles were then determined simultaneously on an SGE (Austin, TX, USA) 30 m BPX70 column. The column was temperature controlled from 175 to 190 8C at 1 8C/min.

3. Results and discussion The oil content of the Chilean seed is statistically similar to the average of 30 samples of commercial seed grown in various regions (Table 3). This is slightly lower than the value reported by Wisniak (1987) as typical of jojoba seed. However, this difference is within the standard deviation of the 17 clones analyzed. Our low moisture content was probably due to handling and storage conditions after the seed was harvested. The low acid value of the seed oil is evidence that the seeds were in good condition when the oil was extracted. The protein content of the Chilean

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Fig. 1. Negative relation between oil content and protein content in jojoba seed meal.

seeds is close to literature values. The indirect proportionality between protein and oil content of the experimental seed, following the normal trend of jojoba seed, is illustrated in Fig. 1. There were discrepancies between the result of oil content analysis of these seeds and the results earlier Table 4 Oil contents of selected clones compared with Botti et al. (1998) Clone

Oil (%)

Oil (%)a

4.11.32 4.8 4.13.1 1.2.4 74

53.4 47.9 50.9 56.3 52.7

48.4 49.2 50.1 50.3 51.1

a

Botti et al. (1998).

reported by Botti et al. (1998) at the Las Cardas site (Table 4). Due to the large variability of seed size among the Chilean clones, comparison with seeds grown at different locations was not possible. Seeds from different clones collected from the same plantations varied in the weight per 1000 seeds by more than 50% (Table 3), and thus, it appears that factors other than geographic location were responsible for the diversity in seed size. The wax ester molecular weight of the oil of the 17 Chilean clones is slightly higher than that reported by Wisniak (1987), (Table 3), and the commercial seed samples, which were grown on plantations in the United States, Israel, Peru and Argentina, (Table 6).

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Table 5 Total simmondsins and simmondsin/analogs fractions of experimental jojoba seed and literature values Total simmondsins Chilean seed, dehulled (%) Chilean seed, defatted (%) Purcell et al. (2000), defatted (%)

11.09/1.9 22.79/4.0 12.2

Simmondsin

Simmondsin ferulate

2.49/0.8 5.09/1.7 1.8

2.09/0.7 4.19/1.3 5.9

dms 4.09/1.0 8.29/1.9 1.7

ddms 2.69/0.3 5.49/0.6 2.8

dms, demethylsimmondsin; ddms, didemethylsimmondsin.

Table 6 Average molecular weight of wax esters from jojoba seed grown in different regions Chile MW (amu) Count

610.39/2.7 17

US 606.29/1.7 13

Higher C42 wax ester and lower C38 wax ester content was found in the Chilean seed (Table 3), compared with the literature and commercial seed samples, which is consistent with the elevated average molecular weight. T -tests comparing the Chilean samples with the commercial samples assert systematic differences at a 99.97% confidence level for the wax ester molecular weight and near 100% for C42 and C38 wax ester content. Further, the average molecular weight of the fatty alcohol moiety of the Chilean wax esters was slightly lower than Wisniak (1987), whereas the average molecular weight of the fatty acid moiety was higher. This suggests that the longer chain fatty acids may be responsible for the observed increase in wax ester molecular weight. Many factors affect wax ester, fatty acid and fatty alcohol molecular weight, including genetics, geographical location, and environmental factors such as temperature and salinity. Ayerza (2001) reported that oil from seed grown in Argentina and Peru had a molecular weight greater than the commercial value, with larger C42 and lower C40 content and suggested that this might be attributed to the low temperatures in these regions. Another factor possibly affecting molecular weight is salinity. The seeds for this study were obtained from plants grown under non-saline conditions at the Las Cardas research station. However, the parent plants from which the

Israel 607.49/0.98 11

Peru and Argentina 607.49/1.5 10

cuttings originated were grown under conditions of extremely high salinity. The soil of the plantations from which the parent plants were collected had an average electrical conductivity of 38 dS/m and the water had an average conductivity of 5 /7 dS/m. Benzioni and Vaknin (2002) found that the chain-lengths of wax esters, fatty acids and fatty alcohols of salt-sensitive plants decreased in response to high salinity. Therefore, the Chilean plants either have high resistance to salinity or the effect of high salinity was not present once the stress was removed. It is also possible that the effect of high salinity experienced by the parent plants was eclipsed by other factors. This property of the Chilean seed should not affect its suitability for current commercial applications. The simmondsin data are summarized in Table 5. A higher concentration of simmondsins (simmondsin plus its analogs) is present in the experimental Chilean seed than in commercial jojoba seed. The relative concentrations of the four simmondsin species are also different. In the Chilean seed, DMS comprised more of the total simmondsins and simmondsin comprised less than the commercial seed (Purcell et al., 2000). These contrasting results could be attributed to many factors, and whether Chilean growing conditions contributed to the higher total simmondsins yield will require further investigation when commercial jojoba plantations are established in this region.

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4. Conclusion

References

The experimental Chilean jojoba seed had physical properties similar to literature values and comparison samples from various regions of the world, including the weight per 1000 seeds, oil and protein contents, and acid value. However, there were differences in the chemical composition. The molecular weight of the wax esters comprising the Chilean oil, as well as the fatty acid moiety of the wax esters were greater than the literature values and comparison samples. Further, the wax ester profile of the Chilean seed oil had a greater C42 and a lower C38 content than the jojoba oil from seeds grown in the United States, Peru, Argentina, and Israel. In addition to these differences, the total simmondsins content (the combined content of simmondsin, simmondsin ferulate, DMS, and DDMS) of the Chilean seed meal was greater than values previously reported (Purcell et al., 2000). The ratio of simmondsin content to that of its analogs (simmondsin ferulate, DMS, and DDMS) was also considerably lower in the Chilean seed than the values reported in the literature. The differences in chemical composition of the Chilean jojoba seed should not reduce its usefulness as a commercial seed oil. Most cosmetic applications would be unaffected by a minor increase in molecular weight. A high simmondsins content should not impact most cosmetic applications, and instead could be beneficial to pharmaceutical or nutritional applications where the appetite-suppressing properties of jojoba meal are involved.

Abbott, T., Flora, G., Frank, L., Holser, R., Kolodziejczyk, P., York, D., Nelsen, T., 2000. Interlaboratory comparison of simmondsin analysis. Ind. Crops Prod. 12, 209 /213. American Oil Chemists’ Society, 1998. Official Methods and Practices of the AOCS, 5th ed. Champaign, IL. Ba 2a-38 and Ci 4-91. AOAC, 1990. Protein (Crude) Determination in Animal Feed: Copper Catalyst Kjeldahl Method. (984.13) Official Methods of Analysis, 1990. Association of Official Analytical Chemists. 15th edition. Ayerza, R., 1996. Neuvos cultivos industriales en sudamerica. Jojoba: Proceedings of 9th International Conference on Jojoba and its Uses. AAIC, Peoria, IL. pp. 187 /191. Ayerza, R., 2001. Wax /ester composition of ten jojoba clones growing in two arid ecosystems of South America. Trop. Sci. 41, 168 /171. Ayerza, R., Coates, W., 1992. International reports highlight symposium: an update on the status of jojoba in Latin America. Jojoba Happenings 20(4) July /August, 1 /2, 6. Benzioni, A., Vaknin, Y., 2002. Effect of female and male genotypes and environment in wax composition in jojoba. J. Am. Oil Chem. 79 (3), 297 /302. Botti, C., 1992. Chile takes another look at jojoba. Jojoba Happenings 20 (2), 1. Botti, C., Prat, L., Palzkill, D., Canaves, L., 1998. Evaluation of jojoba clones grown under water and alkalinity stresses in chile. Ind. Crops Prod. 9, 39 /45. Ceron, W., Delatorre, J., 1984. Jojoba experimental planting in Chile. Jojoba: Proceedings of 6th International Conference on Jojoba and its Uses, October 21 /26, Beer-Sheva, Israel, pp. 43 /51. International Flora Technologies, Ltd., 2001. Weight Reduction Method for Cats and Other Pets. U.S. Patent No. 6,245,364. Purcell, H., Abbott, T., Holser, R., Phillips, B., 2000. Simmondsin and wax ester levels in 100 high-yielding jojoba clones. Ind. Crops Prod. 12, 151 /157. Wisniak, J., 1987. The Chemistry and Technology of Jojoba Oil. American Oil Chemists’ Society, Champaign, IL, p. 43.