Fatty Acid Composition, Phytochemistry, Antioxidant Activity on Seed Coat and Kernel of Paeonia ostii from Main Geographic Production Areas

Abstract

Paeonia ostii is an important woody oil plant cultivated in China on a large scale. Its seed oil is enriched with unsaturated fatty acids and a high content of alpha-linolenic acid (ALA), which are beneficial to human health. The aim of this research is to determine the qualitative traits characteristic of P. ostii seed from various production areas in China. In this study, seed quality traits were evaluated on the basis of proximate composition, content of fatty acids, tocopherol, secondary metabolites, and the antioxidant activity of seed coat (PSC) and kernel (PSK). A high content of total fatty acids (298.89-399.34 mg g −1 ), crude protein (16.91%-22.73%), and total tocopherols (167.83-276.70 µg g −1 ) were obtained from PSK. Significant differences were found in the content of palmitic acids (11.31-14.27 mg g −1 ), stearic acids (2.42-4.24 mg g −1 ), oleic acids (111.25-157.63 mg g −1 ), linoleic acids (54.39-83.59 mg g −1 ), and ALA (99.85-144.71 mg g −1 ) in the 11 main production areas. Eight and seventeen compounds were detected in PSC and PSK, respectively. A significantly higher content of total phenols was observed in PSC (139.49 mg g −1 ) compared with PSK (3.04 mg g −1 ), which was positively related to antioxidant activity. This study indicates that seeds of P. ostii would be a good source of valuable oil and provides a basis for seed quality evaluation for the production of edible oil and potential ALA supplements from the promising woody oil plant.

Integrated Profiling of Fatty Acids, Sterols and Phenolic Compounds in Tree and Herbaceous Peony Seed Oils: Marker Screening for New Resources of Vegetable Oil

“…Paeoniflorin was also reported in the seeds of P. rockii and P. ostii , which were in higher quantities than the aforementioned phenolic compounds (15.03 mg/g dry and 15.57 mg/g dry seeds [ 27 ], respectively) as we also observed in the oils. Albiflorin, paeoniflorin and suffruticosol A and C were also found in the seed coat and kernel of P. ostii , which explains their presence in the oil [ 28 ]. Moreover, as for phenolic glycosides, mudanoside A (1.55–7.35 μg/g) and paeonol (1.30–5.84 μg/g) were the main compounds.…”

Ecotopic over‐expression of PoCHS from Paeonia ostii altered the fatty acids composition and content in Arabidopsis thaliana

“…However, long‐chain fatty acids (>C20:0) were not detected in P. ostii seeds, therefore, in future studies, we would try to overcome tree peony transformation problem and use it for endogenous functional analysis of the PoCHS genes. In addition, the seed oil of P. ostii has a high ALA content (42% of total seed fatty acids), which demonstrated an obvious advantage compared with the common vegetable oil such as soybean and oliver oil for human consumption and health requirement (Li et al, 2015; Peng et al, 2020). The metabolic engineering of flavonoid biosynthesis, especially by manipulating PoCHS expression, would be an effective way to further increase the content of ALA making peony tree a superstar of healthy vegetable oil for dietary supplements.…”

“…Mature seeds from transgenic Arabidopsis plants were collected for fatty acids characterization using the established method in our laboratory. Seeds collected from one plant (3.0 mg) were used for lipid extraction, and fatty acid methyl ester (FAMEs) analyses were performed according to Peng et al (2020). The total flavonoids analysis was performed according to the previously described method of Li et al (2009).…”

“…P. ostii is one of the most important species that is widely but sporadically cultivated in China as traditional medicine. Recently, it has been reported that the seeds of P. ostii contain a lot of oil (22%) that is high in unsaturated fatty acids (>92%), especially α‐linolenic acid (ALA, ≥42%) and has a low ratio (<1) of n‐6:n‐3 (Peng et al, 2020). As a high‐quality edible oil with a good source of ALA, P. ostii seed oil has greater therapeutic potential and health‐promoting effects compared with those of animal‐derived fats (Bhat & Reddy, 2017).…”

Transcriptomic analysis of a-linolenic acid content and biosynthesis in Paeonia ostii fruits and seeds

“…In castor beans and oil palms, transcriptome analyses showed that differences in FAs among seed tissues were associated with certain genes and transcription factors (TFs) [22,23]. Interestingly, previous studies have showed that FA composition and relative abundance differ among wild P. ostii trees [6,9], as well as among seed kernels and testas [6,24].…”