TY - JOUR A1 - Shi, Jiang A1 - Xie, Dongchao A1 - Qi, Dandan A1 - Peng, Qunhua A1 - Chen, Zongmao A1 - Schreiner, Monika A1 - Lin, Zhi A1 - Baldermann, Susanne T1 - Methyl jasmonate-induced changes of flavor profiles during the processing of Green, Oolong, and Black Tea JF - Frontiers in plant science N2 - Tea aroma is one of the most important factors affecting the character and quality of tea. Here we describe the practical application of methyl jasmonate (MeJA) to improve the aroma quality of teas. The changes of selected metabolites during crucial tea processing steps, namely, withering, fixing and rolling, and fermentation, were analyzed. MeJA treatment of tea leaves (12, 24, 48, and 168 h) greatly promotes the aroma quality of green, oolong, and black tea products when comparing with untreated ones (0 h) and as confirmed by sensory evaluation. MeJA modulates the aroma profiles before, during, and after processing. Benzyl alcohol, benzaldehyde, 2-phenylethyl alcohol, phenylacetaldehyde, and trans-2-hexenal increased 1.07- to 3-fold in MeJA-treated fresh leaves and the first two maintained at a higher level in black tea and the last two in green tea. This correlates with a decrease in aromatic amino acids by more than twofold indicating a direct relation to tryptophan- and phenylalanine-derived volatiles. MeJA-treated oolong tea was characterized by a more pleasant aroma. Especially the terpenoids linalool and oxides, geraniol, and carvenol increased by more than twofold. KW - methyl jasmonate KW - aroma quality KW - volatile compounds KW - amino acids KW - tea processing Y1 - 2019 U6 - https://doi.org/10.3389/fpls.2019.00781 SN - 1664-462X VL - 10 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Yadav, Heena A1 - Dreher, Dorothée A1 - Athmer, Benedikt A1 - Porzel, Andrea A1 - Gavrin, Aleksandr A1 - Baldermann, Susanne A1 - Tissier, Alain A1 - Hause, Bettina T1 - Medicago TERPENE SYNTHASE 10 is involved in defense against an oomycete root pathogen JF - Plant physiology : an international journal devoted to physiology, biochemistry, cellular and molecular biology, biophysics and environmental biology of plants N2 - In nature, plants interact with numerous beneficial or pathogenic soil-borne microorganisms. Plants have developed various defense strategies to expel pathogenic microbes, some of which function soon after pathogen infection. We used Medicago truncatula and its oomycete pathogen Aphanomyces euteiches to elucidate early responses of the infected root. A. euteiches causes root rot disease in legumes and is a limiting factor in legume production. Transcript profiling of seedlings and adult plant roots inoculated with A. euteiches zoospores for 2 h revealed specific upregulation of a gene encoding a putative sesquiterpene synthase (M. truncatula TERPENE SYNTHASE 10 [MtTPS10]) in both developmental stages. MtTPS10 was specifically expressed in roots upon oomycete infection. Heterologous expression of MtTPS10 in yeast led to production of a blend of sesquiterpenes and sesquiterpene alcohols, with NMR identifying a major peak corresponding to himalachol. Moreover, plants carrying a tobacco (Nicotiana tabacum) retrotransposon Tnt1 insertion in MtTPS10 lacked the emission of sesquiterpenes upon A. euteiches infection, supporting the assumption that the identified gene encodes a multiproduct sesquiterpene synthase. Mttps10 plants and plants with reduced MtTPS10 transcript levels created by expression of an MtTPS10-artificial microRNA in roots were more susceptible to A. euteiches infection than were the corresponding wild-type plants and roots transformed with the empty vector, respectively. Sesquiterpenes produced by expression of MtTPS10 in yeast also inhibited mycelial growth and A. euteiches zoospore germination. These data suggest that sesquiterpene production in roots by MtTPS10 plays a previously unrecognized role in the defense response of M. truncatula against A. euteiches. Y1 - 2019 U6 - https://doi.org/10.1104/pp.19.00278 SN - 0032-0889 SN - 1532-2548 VL - 180 IS - 3 SP - 1598 EP - 1613 PB - American Society of Plant Physiologists CY - Rockville ER - TY - JOUR A1 - Frede, Katja A1 - Schreiner, Monika A1 - Baldermann, Susanne T1 - Light quality-induced changes of carotenoid composition in pak choi Brassica rapa ssp. chinensis N2 - Carotenoids as part of the photosystems are crucial for their assembly, light-harvesting, and photoprotection. Light of different wavelengths impacts the composition and structure of photosystems, thus offering the possibility to influence the carotenoid concentrations and composition in photosystems by illumination with specific narrow-banded light spectra. Key components involved in the regulation of gene transcription are still poorly characterized, particularly in leafy vegetables as compared to model plants. In particular, the effect of different light qualities and its connection to redox control mechanisms, which also determine the photosystem composition and structure, is not yet well understood. Furthermore, light quality effects are species-dependent, and thus, increase the need to perform research on individual vegetable species such as pak choi Brassica rapa ssp. chinensis. Here, we investigated the carotenoid concentrations and composition of pak choi sprouts grown for 6 days under blue, red, or white light emitting diodes (LEDs) as light source. After 6 days, the total carotenoid content was the highest under white and slightly reduced under blue or red LEDs. Blue, red, and white light differently affected the carotenoid composition mainly due to variations of the beta-carotene content which could be correlated to changes in the transcript levels of beta-carotene hydroxylase 1 (beta-OHASE1). Further investigations implied a redox controlled gene expression of beta-OHASE1. In addition, transcription factors related to light signaling and the circadian clock differed in their transcriptional abundance after exposure to blue and red light. RNA-Seq analysis also revealed increased transcript levels of genes encoding the outer antenna complex of photosystem II under red compared to blue light, indicating an adjustment of the photosystems to the different light qualities which possibly contributed to the alternations in the carotenoid content and composition. KW - Brassica rapa ssp. chinensis KW - beta-carotene hydroxylase KW - Carotenoids KW - LEDs KW - Light quality KW - Redox control Y1 - 2019 U6 - https://doi.org/10.1016/j.jphotobiol.2019.02.001 SN - 1011-1344 VL - 193 SP - 18 EP - 30 PB - Elsevier CY - Lausanne ER - TY - JOUR A1 - Olayide, Priscilla A1 - Large, Annabel A1 - Stridh, Linnea A1 - Rabbi, Ismail A1 - Baldermann, Susanne A1 - Stavolone, Livia A1 - Alexandersson, Erik T1 - Gene expression and metabolite profiling of thirteen Nigerian cassava landraces to elucidate starch and carotenoid composition JF - Agronomy N2 - The prevalence of vitamin A deficiency in sub-Saharan Africa necessitates effective approaches to improve provitamin A content of major staple crops. Cassava holds much promise for food security in sub-Saharan Africa, but a negative correlation between beta-carotene, a provitamin A carotenoid, and dry matter content has been reported, which poses a challenge to cassava biofortification by conventional breeding. To identify suitable material for genetic transformation in tissue culture with the overall aim to increase beta-carotene and maintain starch content as well as better understand carotenoid composition, root and leaf tissues from thirteen field-grown cassava landraces were analyzed for agronomic traits, carotenoid, chlorophyll, and starch content. The expression of five genes related to carotenoid biosynthesis were determined in selected landraces. Analysis revealed a weak negative correlation between starch and beta-carotene content, whereas there was a strong positive correlation between root yield and many carotenoids including beta-carotene. Carotenoid synthesis genes were expressed in both white and yellow cassava roots, but phytoene synthase 2 (PSY2), lycopene-epsilon-cyclase (LCY epsilon), and beta-carotenoid hydroxylase (CHY beta) expression were generally higher in yellow roots. This study identified lines with reasonably high content of starch and beta-carotene that could be candidates for biofortification by further breeding or plant biotechnological means. KW - carotenoid biosynthesis KW - ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) KW - provitamin A KW - biofortification Y1 - 2020 U6 - https://doi.org/10.3390/agronomy10030424 SN - 2073-4395 VL - 10 IS - 3 SP - 1 EP - 16 PB - MDPI CY - Basel ER - TY - JOUR A1 - Odongo, Grace Akinyi A1 - Schlotz, Nina A1 - Baldermann, Susanne A1 - Neugart, Susanne A1 - Ngwene, Benard A1 - Schreiner, Monika A1 - Lamy, Evelyn T1 - Effects of Amaranthus cruentus L. on aflatoxin B1- and oxidative stress-induced DNA damage in human liver (HepG2) cells JF - Food bioscience N2 - Amaranth is presently an underutilized crop despite its high content of micronutrients/bioactive phytochemicals and its capacity to thrive in harsh environmental condition. The present study aimed at determining the health benefits of Amaranthus cruentus L. in terms of protection against DNA damage induced by the mycotoxin aflatoxin B1 (AFB1) and oxidative stress using comet assay. The antioxidant potential was further investigated using electron paramagnetic resonance spectroscopy (EPR) and an ARE/Nrf2 reporter gene assay in vitro in a human liver model using the HepG2 cell line. Ethanolic extracts from fresh leaves grown under controlled conditions were used and additionally analyzed for their phytochemical content using liquid chromatography-mass spectrometry (LC-MS). The extracts inhibited both AFB1- and oxidative stress-induced DNA damage in a concentration dependent way with a maximum effect of 57% and 81%, respectively. Oxidative stress triggered using ferrous sulfate was blocked by up to 38% (EPR); the potential to induce antioxidant enzymes using ARE/Nrf2-mediated gene expression was also confirmed. Based on these in vitro findings, further studies on the health-protecting effects of A. cruentus are encouraged to fully explore its health promoting potential and provide the scientific basis for encouraging its cultivation and consumption. KW - African indigenous vegetables KW - Aflatoxin B1 KW - Amaranthaceae KW - Amaranth KW - Aspergillus KW - Cancer prevention Y1 - 2018 U6 - https://doi.org/10.1016/j.fbio.2018.09.006 SN - 2212-4292 SN - 2212-4306 VL - 26 SP - 42 EP - 48 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Klopsch, Rebecca A1 - Baldermann, Susanne A1 - Hanschen, Franziska S. A1 - Voss, Alexander A1 - Rohn, Sascha A1 - Schreiner, Monika A1 - Neugart, Susanne T1 - Brassica-enriched wheat bread: Unraveling the impact of ontogeny and breadmaking on bioactive secondary plant metabolites of pak choi and kale JF - Food chemistry N2 - Consumption of Brassica vegetables is linked to health benefits, as they contain high concentrations of the following secondary plant metabolites (SPMs): glucosinolate breakdown products, carotenoids, chlorophylls, and phenolic compounds. Especially Brassica vegetables are consumed as microgreens (developed cotyledons). It was investigated how different ontogenetic stages (microgreens or leaves) of pak choi (Brassica rapa subsp. chinensis) and kale (Brassica oleracea var. sabellica) differ in their SPM concentration. The impact of breadmaking on SPMs in microgreens (7 days) and leaves (14 days) in pak choi and kale as a supplement in mixed wheat bread was assessed. In leaves, carotenoids, chlorophylls, and phenolic compounds were higher compared to those of microgreens. Breadmaking caused a decrease of SPMs. Chlorophyll degradation was observed, leading to pheophytin and pyropheophytin formation. In kale, sinapoylgentiobiose, a hydroxycinnamic acid derivative, concentration increased. Thus, leaves of Brassica species are suitable as natural ingredients for enhancing bioactive SPM concentrations in bread. KW - Ontogeny KW - Brassica KW - Glucosinolate breakdown product KW - Flavonoid KW - Carotenoid KW - Thermal processing Y1 - 2019 U6 - https://doi.org/10.1016/j.foodchem.2019.05.113 SN - 0308-8146 SN - 1873-7072 VL - 295 SP - 412 EP - 422 PB - Elsevier CY - Oxford ER -