Abstract Paeonia ostii is an industrial crop with broad prospects, and folks have habit of drinking its stamen tea in China, but its beneficial healthy effects remain largely unclear. Here, we identified its main active components, evaluated its antioxidant activity, and examined its safety property and its beneficial effects in the model animal Caenorhabditis elegans. The results showed that P. ostii stamen (POS) contained many active components with high antioxidant activity. Moreover, POS tea did not cause lethality, influence growth, locomotion behavior and reproduction, and induce intestinal autofluorescence in C. elegans. Furthermore, 1.2 mg·mL-1 of POS tea treatment significantly extended the lifespan and improved growth, locomotion behavior and intestinal autofluorescence of C. elegans, while its reproduction and Escherichia coli OP50 growth were not affected. In addition, POS tea treatment significantly induced stress resistance to extend the lifespan of C. elegans under heat stress and oxidative stress conditions. All these suggested that POS tea was safe and had beneficial healthy effects, which could provide a theoretical basis for its production and popularization.

Resumo: Sementes de muitas espécies de peônia contêm grande conteúdo de lipídios. No entanto, a exploração de seu potencial para a produção de óleo é dificultada pela falta de informações básicas sobre a biologia do desenvolvimento das sementes. Objetivou-se determinar o acúmulo de vários compostos de reserva durante o desenvolvimento de sementes da espécie Paeonia lactiflora ‘Hangshao’. As sementes foram coletadas em cinco estádios de desenvolvimento: 30 dias após a floração (DAF), 45 DAF, 60 DAF, 75 DAF e 90 DAF. Foram realizadas análises anatômicas e histológicas e o peso de sementes, conteúdo de água, proteínas, amido e ácidos graxos foram determinados. O período de tempo para o completo desenvolvimento das sementes foi de 90 DAF. As sementes estavam fisiologicamente maduras aos 75 DAF. Durante o desenvolvimento das sementes, o conteúdo de amido e de lipídio aumentaram para, em seguida, diminuir, atingindo o conteúdo máximo aos 60 DAF e aos 75 DAF, respectivamente. O teor de proteínas apresentou uma ligeira diminuição e, em seguida, aumentou. Lipídio foi o principal composto de reserva presente nas sementes maduras. Um total de 26 tipos de ácidos graxos foram detectados entre os quais, sete tipos atingiram mais de 100 mg.Kg-1 em sementes de todos os estádios de desenvolvimento. Esses sete ácidos graxos foram ácido palmítico, ácido esteárico, ácido oleico, ácido trans-oleico, ácido linoleico, ácido α-linolenic e ácido erécico. Além disso, o teor de ácido α-linolenic representou mais de 40% do teor total de ácidos graxos em cada estádio.

Abstract: Seeds of many peony species contain a large amount of oil. However, the exploiting of its potential for oil production is hampered by a lack of basic information regarding the developmental biology of the seeds. Our aim was to obtain a detailed relationship between seed development and accumulation of various storage compounds of Paeonia lactiflora ‘Hangshao’ seed. Seeds were collected at five developmental stages including 30 days after flowering (DAF), 45 DAF, 60 DAF, 75 DAF and 90 DAF. Anatomical and histological analysis, seed weight and water content, proteins, starch, and fatty acids contents were determinated. The time span of seed development for P. lactiflora ‘Hangshao’ was 90 DAF. Seeds were physiologically mature by 75 DAF, with maximum dry matter content. During seed development, the starch and lipid content showed an increased and then decrease pattern, while they reached their maximum content differed with starch for 60 DAF and lipid for 75 DAF. Protein content showed a slight decreased and then increased pattern. Lipid was the main storage reserve of mature seeds. A total of 26 kinds of fatty acid were detected and among which, seven kinds was all more than 100 mg.Kg-1 in all developmental seeds. Those seven fatty acids were palmitic acid, stearic acid, oleic acid, trans-oleic acid, linoleic acid, α-linolenic acid, and erucic acid. Besides, the content of α-linolenic acid accounted for more than 40% of the total fatty acid content in each stage.

Herbaceous peony (Paeonia lactiflora Pall.) is an excellent material for studying the formation of flower colour because of its abundant colour. The full-length cDNA of a UDP-glucose: Flavonoid 5-O-glucosyltransferase gene (UF5GT) containing 1629 bp nucleotides was obtained from P. lactiflora. The expression patterns of nine related anthocyanin biosynthetic genes (PlPSY, PlCHS, PlCHI, PlF3H, PlF3'H, PlDFR, PlANS, PlUF3GT and PlUF5GT) in diurnal variation petals showed that their expression peaks were basically at 15:00 and the expression patterns were consistent with the trend of sampling conditions except individual gene. And the highest expression levels were in PlCHS, PlDFR and PlUF3GT, which could be the candidates to regulate P. lactiflora flower colour by means of genetic engineering.