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991.
Chemodiversity in the Fingerprint Analysis of Volatile Organic Compounds (VOCs) of 35 Old and 7 Modern Apple Cultivars Determined by Proton‐Transfer‐Reaction Mass Spectrometry (PTR‐MS) in Two Different Seasons
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Flavio Ciesa Irene Höller Walter Guerra Jennifer Berger Josef Dalla Via Michael Oberhuber 《化学与生物多样性》2015,12(5):800-812
Volatile organic compounds (VOCs) are chemical species that play an important role in determining the characteristic aroma and flavor of fruits. Apple (Malus × domestica Borkh .) cultivars differ in their aroma and composition of VOCs. To determine varietal differences in the aroma profiles, VOCs emitted by 7 modern and 35 old apple cultivars were analyzed using Proton Transfer Reaction Mass Spectrometry (PTR‐MS). PTR‐MS is a rapid, reproducible, and non‐destructive spectrometric technique for VOC analysis of single fruits, developed for direct injection analysis. In the present study, we analyzed the differences in the emission of VOCs from single fruits at harvest and after a storage period of 60±10 days, followed by 3 d of shelf life. Our results show that VOC profile differences among apple cultivars were more pronounced after storage than at harvest. Furthermore, chemodiversity was higher in old cultivars compared to modern cultivars, probably due to their greater genetic variability. Our data highlight the importance of storage and shelf life are crucial for the development of the typical aroma and flavor of several apple cultivars. The validity of the method is demonstrated by comparison of two different harvest years. 相似文献
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Madhav P. Thakur Helen R. P. Phillips Ulrich Brose Franciska T. De Vries Patrick Lavelle Michel Loreau Jerome Mathieu Christian Mulder Wim H. Van der Putten Matthias C. Rillig David A. Wardle Elizabeth M. Bach Marie L. C. Bartz Joanne M. Bennett Maria J. I. Briones George Brown Thibaud Decaëns Nico Eisenhauer Olga Ferlian Carlos Antnio Guerra Birgitta Knig‐Ries Alberto Orgiazzi Kelly S. Ramirez David J. Russell Michiel Rutgers Diana H. Wall Erin K. Cameron 《Biological reviews of the Cambridge Philosophical Society》2020,95(2):350-364
Soil is one of the most biodiverse terrestrial habitats. Yet, we lack an integrative conceptual framework for understanding the patterns and mechanisms driving soil biodiversity. One of the underlying reasons for our poor understanding of soil biodiversity patterns relates to whether key biodiversity theories (historically developed for aboveground and aquatic organisms) are applicable to patterns of soil biodiversity. Here, we present a systematic literature review to investigate whether and how key biodiversity theories (species–energy relationship, theory of island biogeography, metacommunity theory, niche theory and neutral theory) can explain observed patterns of soil biodiversity. We then discuss two spatial compartments nested within soil at which biodiversity theories can be applied to acknowledge the scale‐dependent nature of soil biodiversity. 相似文献
994.
Faria Daniele Vidal de Freitas Correia Ludmila Nayara Batista Diego Silva Vital Camilo Elber Heringer Angelo Schuabb De-la-Peña Clelia Costa Marcio Gilberto Cardoso Guerra Miguel Pedro Otoni Wagner Campos 《Plant Cell, Tissue and Organ Culture》2020,142(2):425-434
Plant Cell, Tissue and Organ Culture (PCTOC) - Bixa orellana L. seeds are an important source of the liposoluble apocarotenoid bixin and the natural hydrosoluble dye norbixin. These natural dyes... 相似文献
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998.
Lessa JA Guerra JC de Miranda LF Romeiro CF Da Silva JG Mendes IC Speziali NL Souza-Fagundes EM Beraldo H 《Journal of inorganic biochemistry》2011,105(12):1729-1739
Complexes [Au(H2Ac4DH)Cl]?MeOH (1) [Au(H22Ac4Me)Cl]Cl (2) [Au(H22Ac4Ph)Cl]Cl?2H2O (3) and [Au(H22Bz4Ph)Cl]Cl (4) were obtained with 2-acetylpyridine thiosemicarbazone (H2Ac4DH), its N(4)-methyl (H2Ac4Me) and N(4)-phenyl (H2Ac4Ph) derivatives, as well as with N(4)-phenyl 2-benzoylpyridine thiosemicarbazone (H2Bz4Ph). The compounds were cytotoxic to Jurkat (immortalized line of T lymphocyte), HL-60 (acute myeloid leukemia), MCF-7 (human breast adenocarcinoma) and HCT-116 (colorectal carcinoma) tumor cell lines. Jurkat and HL-60 cells were more sensitive than MCF-7 and HCT-116 cells. Upon coordinating to the gold(I) metal centers in complexes (2) and (4), the cytotoxic activity of the H2Ac4Me and H2Bz4Ph ligands increased against the HL-60 and Jurkat tumor cell lines. 2 was more active than auranofin against both leukemia cells. Most of the studied compounds were less toxic than auranofin to peripheral blood mononuclear cells (PBMC). All compounds induced DNA fragmentation in HL-60 and Jurkat cells indicating their pro-apoptotic potential. Complex (2) strongly inhibited the activity of thioredoxin reductase (TrxR), which suggests inhibition of TrxR to be part of its mechanism of action. 相似文献
999.
Background and Aims
Secondary somatic embryogenesis has been postulated to occur during induction of peach palm somatic embryogenesis. In the present study this morphogenetic pathway is described and a protocol for the establishment of cycling cultures using a temporary immersion system (TIS) is presented.Methods
Zygotic embryos were used as explants, and induction of somatic embryogenesis and plantlet growth were compared in TIS and solid culture medium. Light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to describe in vitro morphogenesis and accompany morpho-histological alterations during culture.Key Results
The development of secondary somatic embryos occurs early during the induction of primary somatic embryos. Secondary somatic embryos were observed to develop continually in culture, resulting in non-synchronized development of these somatic embryos. Using these somatic embryos as explants allowed development of cycling cultures. Somatic embryos had high embryogenic potential (65·8 ± 3·0 to 86·2 ± 5·0 %) over the period tested. The use of a TIS greatly improved the number of somatic embryos obtained, as well as subsequent plantlet growth. Histological analyses showed that starch accumulation precedes the development of somatic embryos, and that these cells presented high nucleus/cytoplasm ratios and high mitotic indices, as evidenced by DAPI staining. Morphological and SEM observations revealed clusters of somatic embryos on one part of the explants, while other parts grew further, resulting in callus tissue. A multicellular origin of the secondary somatic embryos is hypothesized. Cells in the vicinity of callus accumulated large amounts of phenolic substances in their vacuoles. TEM revealed that these cells are metabolically very active, with the presence of numerous mitochondria and Golgi apparatuses. Light microscopy and TEM of the embryogenic sector revealed cells with numerous amyloplasts, large nuclei and nucleoli, and numerous plasmodesmata. Plantlets were obtained and after 3 months in culture their growth was significantly better in TIS than on solid culture medium. However, during acclimatization the survival rate of TIS-grown plantlets was lower.Conclusions
The present study confirms the occurrence of secondary somatic embryos in peach palm and describes a feasible protocol for regeneration of peach palm in vitro. Further optimizations include the use of explants obtained from adult palms and improvement of somatic embryo conversion rates. 相似文献1000.
Santos-Aberturas J Vicente CM Guerra SM Payero TD Martín JF Aparicio JF 《The Journal of biological chemistry》2011,286(11):9150-9161