Isoprostanoids, Isofuranoids and Isoketals ‐ From Synthesis to Lipidomics

International audienceA huge diversity of oxygenated metabolites originatedfrom polyunsaturated fatty acids (PUFAs) had been discovereddiscovered. Radical cascades are involved in the biosynthesis ofthese metabolites, and the radical initiation can be performed eitherinside the active site of an enzyme in the extracellular medium, or inmembrane on phospholipids. The development of convergent andflexible chemical strategies to prepare these compounds by organicchemists, along with the development of sophisticated massspectrometry methods has boosted the knowledge regarding PUFAmetabolites. Also, isoprostanoids have emerged as indicators ofoxidative stress in humans and their environment. This reviewprovides a brief overview on the chemical strategies and analyticalmethods achieved over the past thirty years

First Total Syntheses of Novel Non‐Enzymatic Polyunsaturated Fatty Acid Metabolites and Their Identification in Edible Oils

International audienc

From MS/MS library implementation to molecular networks: Exploring oxylipin diversity with NEO-MSMS

Abstract Oxylipins, small polar molecules derived from the peroxidation of polyunsaturated fatty acids (PUFAs), serve as biomarkers for many diseases and play crucial roles in human physiology and inflammation. Despite their significance, many non-enzymatic oxygenated metabolites of PUFAs (NEO-PUFAs) remain poorly reported, resulting in a lack of public datasets of experimental data and limiting their dereplication in further studies. To overcome this limitation, we constructed a high-resolution tandem mass spectrometry (MS/MS) dataset comprising pure NEO-PUFAs (both commercial and self-synthesized) and in vitro free radical-induced oxidation of diverse PUFAs. By employing molecular networking techniques with this dataset and the existent ones in public repositories, we successfully mapped a wide range of NEO-PUFAs, expanding the strategies for annotating oxylipins, and NEO-PUFAs and offering a novel workflow for profiling these molecules in biological samples

IRRI upland rice ecosystem program: directions and achievements : directions and achievements

About 17 million hectares of upland rice are grown annually worldwide, with 10.5 million ha in Asia, 3.7 million ha in Latin America, and 2.8 million ha in Africa (IRRI 1993). Total upland production is about 20 million tons. Rice is a major staple crop for upland farmers in many parts of Asia, Africa, and Latin America. The total area supporting upland rice-based cropping is considerably larger because of rotation with fallow and other crops. The crop is grown alone or in diverse mixtures in shifting or permanent fields under a wide range of conditions of climate, slope, and soil type, often as a subsistence crop receiving few purchased inputs, although it is commonly a commercial crop receiving inputs in favourable areas such as Brazil, Indonesia, and the southern Philippines. Reported upland rice areas have remained stable or have increased in some countries, including the major Asian producers Bangladesh, India, and Indonesia, but have declined for others such as Thailand, the Philippines, and Myanmar (Table 1). Care needs to be taken, however, in interpreting upland rice area estimates, which can be unreliable. For example, the 1991 upland rice area in the Philippines was reported as 68,000 ha in the 1993 IRRI Rice Almanac (IRRI 1993), as 17 1,000 ha in the 1997 IRRI Rice Almanac (IRRI 1997), and as 126,000 ha by the Philippine Bureau of Agricultural Statistics (Pandey, unpublished 1997

Gérer collectivement la biodiversité cultivée

National audienceLes semences, avec la terre et l'eau, sont les ressources de l'agriculture. Conserver la maîtrise de ces ressources est un enjeu de souveraineté alimentaire. La biodiversité cultivée, dont les semences font partie, comme les autres ressources, n'échappe pas à la menace d'accaparement par des intérêts privés. Dans ce contexte, sont apparus en France depuis une dizaine d'années des projets de gestion collective de la biodiversité cultivée. Il s'agit de prendre en charge collectivement la gestion in situ des semences à un moment de notre histoire où celle-ci est principalement assurée ex situ par des sélectionneurs et des semenciers professionnels. C'est sur cette gestion collective dans les fermes et les jardins que porte cet ouvrage, une gestion collective qui vise à produire et diffuser des semences, à sélectionner de nouvelles populations de plantes et à conserver les anciennes.L'ouvrage cherche d'abord à susciter l'envie en donnant à voir quatre expériences collectives de gestion de la biodiversité cultivée, autour du maïs et des espèces fourragères, sans pour autant en occulter les difficultés. Ensuite, leur exposé et leur analyse aideront des collectifs qui souhaitent développer leurs propres initiatives à se poser des questions auxquelles ils n'auraient peut-être pas pensé, mais qui semblent déterminantes à prendre en compte pour monter un tel projet. Ce livre souhaite également porter à la connaissance d'un public plus large une thématique insuffisamment connue du grand public, et montrer que d'autres modes de gestion de la biodiversité sont possibles, dont pourraient s'emparer les formations agricoles et environnementales