Is the Profile of Fatty Acids, Tocopherols, and Amino Acids Suitable to Differentiate Pinus armandii Suspicious to Be Responsible for the Pine Nut Syndrome from Other Pinus Species?

Abstract

Pinus armandii is suspicious to be responsible for the Pine Nut Syndrome, a long lasting bitter and metallic taste after the consumption of pine nuts. To find chemical characteristic features for the differentiation of P. armandii from other Pinus species, 41 seed samples of the genus Pinus from 22 plant species were investigated regarding the content and the composition of fatty acids, tocopherols, and amino acids. The predominant fatty acids in the seed oils were linoleic acid (35.2 -58.2 g/100 g), oleic acid (14.6 -48.5 g/100 g), and pinolenic acid (0.2 -22.4 g/100 g), while the vitamin-E-active compounds were dominated by c-tocopherol. The amino acid composition was mainly characterized by arginine and glutamic acid with amounts between 0.9 and 8.9 g/100 g as well as 2.1 g/100 g and 8.3 g/100 mg. On the basis of this investigation, a Principle Component Analysis has been used to identify the most important components for the differentiation of P. armandii from other Pinus species. Using the data for glutamic acid, 20:2D 5,11 , 18:3D 5,9,12 , 18:1D 9 , and oil content, a classification of the 41 samples into four different groups by cluster analysis was possible, but the characteristic features of P. armandii were too close to some other members of the genus Pinus, making a clear differentiation of this species difficult. Nevertheless, the investigation showed the similarities of different members of the genus Pinus with regard to fatty acids, vitamin-E-active compounds, and amino acids.

Morphological and Chemical Differentiation between Tunisian Populations of Pinus halepensis, Pinus brutia, and Pinus pinaster

“…However, these studies were conducted on few samples collected from only one population that could not reveal the effect of genetic and environmental factors on the vitamin E contents of P. halepensis in Tunisia. In turn, P. pinaster collected from France, Italy and Spain showed variable contents of α ‐tocopherol (55, 2 and 2 mg/kg, respectively), γ ‐tocopherol (286, 93 and 140 mg/kg), and γ ‐tocotrienol (40, 40 and 60 mg/kg) [35] . These values differ from those obtained in our current study.…”

“…The nine seed lipid fractions were characterized by their richness in polyunsaturated (61.0 to 65.7 %) and monounsaturated (22.8 to 27.9 %) fatty acids, where linoleic and oleic (60.5–64 and 21.7–27.1 %, respectively) acids were the major compounds. Our results are in accordance with those reported on several Pinus species, where unsaturated fatty acids constitute more than 90 % of the composition of seed oils, with oleic and linoleic acids being the main components [1,7,9,35,36] …”

A review of the functional effects of pine nut oil, pinolenic acid and its derivative eicosatrienoic acid and their potential health benefits

“…PNO is rich in NMIFAs and LA. PLA is the most abundant NMIFA comprising of 14-19% of the total FAs present in the oil from nuts of P. koraiensis and P. sibirica as well as in a number of other PNOs [3,25]. Furthermore, PLA is known to be metabolised to ETA in several cell types and species [6,8,9,11,13,29,30].…”

“…PLA is the most prevalent NMIFA, typically comprising 14-19% of total FAs in P. koraiensis and P. sibirica (Table 1). Taxoleic and sciadonic acids are reported to comprise approximately 2% and 1 to 1.2% of total FAs in P. koraiensis and P. sibirica [25]. ETA is only found in small quantities (1-3%) in PNOs [26,27].…”

“…Table 1 summarises the FA composition of P. sibirica and P. koraiensis oils as reported in several studies. Matthaus et al [25] report that the fatty acid composition, including the contents of PLA, taxoleic and sciadonic acids, in the nut oils of P. aristate, P. armandii, P. cembra, P. echinata, P. jeffreyi, P. massoniana, P. monticola, P. mugo, P. pinaster, P. pumila, P. resinosa, P. roxburghii, P. sylvestris, P. tabuliformis and P. yunnanensis is very similar to those of P. subirica and P. koraiensis. In contrast, the nut oils from P. eldarica, P. excelsa, P. pinea and P. torreyana are much lower in PLA (very low in the case in P. pinea) and are higher in LA or oleic acid [25].…”