1,721,075 research outputs found
Nutritional and antioxidant value of horticulturae products
No full textThe recent growing interest towards the nutraceutical and antioxidant value of fruit and vegetables has arisen from their content of phytochemicals, which provide desirable health benefits, beyond basic nutrition, to reduce the risk of major chronic diseases [1]. For this reason, it is necessary for the human diet to contain a good proportion of plant antioxidant compounds. Therefore, horticultural science must dedicate more attention to satisfy the expectations of consumers who are demanding more and more high-quality functional foods.
The Special Issue on the “Nutritional and Antioxidant Value of Horticultural Products” has provided readers with novel insights into some ‘unusual’ types of foods. In fact, the articles published included information about edible flowers, Italian green tea, and stinging nettle, along with potato and sweet potato.
Demasi et al. [2] investigated the sensory profile of 17 edible flowers (Figure 1) at harvest, and their shelf life and bioactive compound dynamics during cold storage, providing the characteristics and requirements of the different flowers. The authors evaluated the aroma of the flower with 10 sensory descriptors (intensity of sweet, sour, bitter, salt, smell, specific flower aroma, and herbaceous aroma; spiciness, chewiness, and astringency), and, both at harvest and during 14 d of storage at 4 °C, the flower visual quality, polyphenol and anthocyanin content, and antioxidant activity were evaluated. The paper presents a lot of information concerning flowers’ sensory profiles, phytochemical characteristics, and shelf life, which are very useful to select suitable species for the edible flower market; for example, a strong aroma was revealed for Allium ursinum, Dianthus carthusianorum, Lavandula angustifolia, and Leucanthemum vulgare, while the flowers with the longest shelf life were Rosa pendulina (14 days) and Rosa canina (10 days)
Peroxisomal activities in attached senescing leaves
No full textRecently it has been demonstrated that detached leaves show glyoxysomal enzyme activities when incubated in darkness for several days. In this report glyoxylate-cycle enzymes have been detected in leaves of rice (Oryza sativa L.) and wheat (Triticum durum L.) from either naturally senescing or dark-treated plants. Isolated peroxisomes of rice and wheat show isocitrate lyase (EC 4.1.3.1), malate synthase (EC 4.1.3.2) and β-oxidation activities. Leaf peroxisomes from dark-induced senescing leaves show glyoxylic-acid-cycle enzyme activities two to four times higher than naturally senescing leaves. The glyoxysomal activities detected in leaf peroxisomes during natural foliar senescence may represent a reverse transition of the peroxisomes into glyoxysomes
Evidences of glyoxylate cycle in peroxisomes of senescent cotyledons.
No full textThe metabolic pathway of the glyoxylate cycle has been investigated in peroxisomes isolated from senescent pumpkin (Cucurbita sp.) cotyledons. beta-oxidation activity, as well as activities of glyoxylate cycle enzymes isocitrate lyase (EC 4.1.3.1), malate synthase (EC 4.1.3.2), malate dehydrogenase (EC 1.1.1.37) and citrate synthase (EC 4.1.3.7) were detected. In order to establish if there is a channelling of acetyl CoA into the glyoxylate cycle, peroxisomes have been incubated with various substrates. The incubations show acetyl CoA utilization by the glyoxylate cycle. When the incubation medium for citrate formation is used, all the label from [1-C-14]acetyl CoA is recovered in citrate, whereas only 18% of the added radioactivity is recovered in malic acid (by isocitrate lyase and malate synthase) after a long incubation time (3 h). Only by feeding peroxisomes with [1,5-C-14]citric acid and exogenous aconitase (EC 4.2.1.3) can a weak formation of other organic acids (glyoxylate and succinate) be noted. The requirement for exogenous aconitase to carry out the peroxisomal glyoxylate cycle points towards the isocitric acid step as a crucial factor for the operation of the global cycle
Aconitase: To be or not to be inside plant glyoxysomes, that is the question
No full textAfter the discovery in 1967 of plant glyoxysomes, aconitase, one the five enzymes involved in the glyoxylate cycle, was thought to be present in the organelles, and although this was found not to be the case around 25 years ago, it is still suggested in some textbooks and recent scientific articles. Genetic research (including the study of mutants and transcriptomic analysis) is becoming increasingly important in plant biology, so metabolic pathways must be presented correctly to avoid misinterpretation and the dissemination of bad science. The focus of our study is therefore aconitase, from its first localization inside the glyoxysomes to its relocation. We also examine data concerning the role of the enzyme malate dehydrogenase in the glyoxylate cycle and data of the expression of aconitase genes in Arabidopsis and other selected higher plants. We then propose a new model concerning the interaction between glyoxysomes, mitochondria and cytosol in cotyledons or endosperm during the germination of oil-rich seeds
Attività proteolitiche, ciclo fogliare e degradazione della ribulosio bisfosfato carbossilasi (RuBisCo) in erba medica (Medicago sativa L.)
No full textarabidopsis thaliana mRNA for 2-isopropylmalate synthase (ipms gene) GenBank: AJ421793.1
No full textLOCUS AJ421793 1767 bp mRNA linear PLN 13-DEC-2001
DEFINITION Arabidopsis thaliana mRNA for 2-isopropylmalate synthase (IPMS
gene).
ACCESSION AJ421793
VERSION AJ421793.1 GI:17826794
KEYWORDS 2-isopropylmalate synthase; IPMS gene.
SOURCE Arabidopsis thaliana (thale cress
Cell fine structure and some enzyme activities in rice coleoptiles grown in air and in anoxia.
No full textEditorial for special issue “heavy metals accumulation, toxicity, and detoxification in plants”
No full text"Heavy metals" is a collective term widely applied for the group of metals and metalloids with an atomic density above 4 g/cm3 [...]
- …
