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A novel combination of transcription factors and chromatin modifiers supporting naïve pluripotency in rabbit stem cells
No full textInternational audienceEmbryo-derived and induced pluripotent stem cells (ESCs and iPSCs, respectively) exist in two different states, designated naive and primed. Naïve and primed states differ by the signalling pathways, transcription factors and epigenetic regulators that hold the cells in one of either state. In rabbits, ESCs and iPSCs only exist in the primed state of pluripotency. We developed a strategy that led to identify factors capable of reprogramming rabbit iPSCs to a naïve-like state. Using rabbit iPSCs as a model system, we conducted an unbiased screening of a cDNA library encoding a panel of 36 factors, including transcription factors, epigenetic regulators and signalling molecules associated with naïve-state pluripotency in rodents and primates. All the factors were randomly introduced into rabbit primed iPSCs by means of lentivector infection, followed by clonogenic growth in a new culture media designated VALGöX.The three transgenes most frequently detected and associated with naive-state pluripotency include an arginine methyl transferase, a GTPase, and a transcription factor of the KLF family (designated KEP transgene combination). In order to confirm their action, these three genes were overexpressed in rabbit iPSC cells. Remarkably, the reprogrammed cells underwent epigenetic reconfiguration typical of naïve-state pluripotency including reactivation of the 2nd X-chromosome, and produced chimeric embryos with a high efficiency. Overall, our findings underscore a synergy between the VALGöX culture regimen and the KEP transgenes, enabling rabbit iPSCs to acquire the molecular and functional characteristics of naïve pluripotency
La « viande de culture » : ce que nous savons et ce qu’il faudrait savoir. Volet A : principes et qualités intrinsèques
No full textInternational audienceProduced from proliferating cells cultivated in bioreactors, “cultured meat” is touted as a solution to the growing demand for animal protein without the drawbacks of livestock. This first article aims to describe its health, nutritional and organoleptic properties based on available knowledge. Particular attention is paid to the composition and the cost of the culture medium, in particular concerning the alternatives to foetal calf serum. The safety of this new food is a matter of debate among scientists, with some affirming that the consumption of “cultured meat” would be safer than that of conventional meat, and others considering that the health risks are not fully known. In view of our current knowledge, it seems unlikely that we will be able to reproduce meat given the complexity of the biological process. Even if the enrichment of the culture medium with micronutrients (iron, vitamin B12, etc.) is envisaged by various startups, the nutritional properties of this new food remain to be studied, especially as the bioavailability of these nutrients extracted from their original matrix is still unknown.Produite à partir de cellules en prolifération dans des bioréacteurs, la « viande de culture » est présentée comme une solution à la demande grandissante en protéines animales sans certains des inconvénients de l’élevage. Ce premier article décrit les qualités sanitaires, nutritionnelles et organoleptiques à partir des connaissances disponibles. Un point d’attention concerne la composition et le coût du milieu de culture, notamment concernant les alternatives au sérum de veau fœtal. L’innocuité de ce nouvel aliment fait débat entre les scientifiques, avec, d’un côté ceux qui affirment que la consommation de la « viande de culture » sera plus sûre que celle de la viande conventionnelle, et ceux qui, au contraire, sont plus prudents, considérant que les risques sanitaires ne sont pas entièrement connus. Au regard de nos connaissances actuelles, il semble peu probable que l’on puisse reproduire de la viande vu la complexité du processus biologique. Et même si l’enrichissement du milieu de culture en micronutriments (fer, vitamine B12, etc.) est envisagé par différentes jeunes entreprises innovantes, les propriétés nutritionnelles de ce nouvel aliment restent à préciser, d’autant plus que la biodisponibilité de ces nutriments apportés en dehors de leur matrice originale est encore inconnue
Inclusion of microbiological food safety as a novel aspect in life cycle assessments of food production
No full textInternational audienceThe life cycle assessment (LCA) methodology currently covers a limited number of human health-related impact categories. Microbiological food safety is an essential aspect for the selection of an appropriate food production system and has been neglected in the LCA so far. A framework for the inclusion of a microbiological food safety indicator, expressed as disability-adjusted life year (DALY) value of the consumed food product to the human health damage category (end-point) was created, and applied in a case study model on the cooked-chilled meals as the ready-to-eat meals can be associated with the occurrence of foodborne illness cases and outbreaks. This study suggests a framework for the inclusion of microbiological risk caused by Bacillus cereus associated with the consumption of ready-to-eat meals (in Belgium) in the LCA. The results indicated that the microbiological risk of one package of the investigated ready-to-eat meal was 1.95 × 10−6 DALY, and the obtained DALY value was included as an impact category in the LCA methodology. Inclusion of other categories of food safety (including chemical safety hazards, pesticide residues, heavy metals, and mycotoxins) in LCA could be done in the same fashion
The environmental impact of permanent meadows-based farms: A comparison among different dairy farm management systems of an Italian cheese
No full textInternational audienceThe environmental impact of dairy production is heavily influenced by milk farm efficiency, farm characteristics, and farming activities, such as feed management. The existing research on the environmental impacts of the differently managed dairy farm systems is often in contrast and difficult to be compared. Thus, the present study aimed to assess the environmental impacts of milk used for the same cheese by comparing four dairy farm systems different for feed management choices, geographical area, herd size and milk productivity. A Life Cycle Assessment was performed following the Product Environmental Footprint methodology using primary data collected in 70 farms and one average cheese factory. The results showed that the raw milk production phase was the most significant contributor to the environmental impacts of cheese production. The self-produced feed and purchased feed resulted as the main hotspot processes, covering 64–77 % of the total impact. In fact, among the four different farm systems, the Permanent Meadows Farms showed the best environmental performance, with the lowest values registered for 14 of 19 impact indicators. Similar impacts were observed for the North Italy Representative Farms, while Small Plain Farms disclosed the highest outcomes, resulting most impacting than the Mountain Farms. Results demonstrate that different feed management choices can affect the final cheese impact and could be considered by private and public policies focused on green transformation objectives
Méthode d'analyse des stratégies en faveur de la biodiversité. Analyse de la capacité à initier un changement transformateur. Application à la troisième stratégie nationale pour la biodiversité (SNB3)
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/604244/)International audienc
Consumer perception of the challenges facing livestock production and meat consumption
No full textInternational audienceWith the global meat market growing and intensive livestock farming systems increasing, the impacts of livestock are a growing concern among consumers, further influencing their meat consumption. Understanding consumer perceptions of livestock production is therefore a key issue. This study surveyed 16,803 respondents in France, Brazil, China, Cameroon and South Africa to investigate the different perceptions of the ethical and environmental impacts of livestock production among consumer segments in different countries based on their sociodemographic characteristics. On average, the current respondents in Brazil and China and/or who consume little meat, are female, not in the meat sector and/or more educated, are more likely to think that livestock meat production causes serious ethical and environmental problems; while those in China, France and Cameroon and/or who consume little meat and/or are women, younger, not in the meat sector, and/or more educated, are more likely to agree that reducing meat consumption could be a good solution to these problems. Additionally, an affordable price and sensory quality are the main drivers of food purchases for the current respondents. In conclusion, sociodemographic factors have significant effects on consumer perception of livestock meat production and meat consumption habits. Perceptions of the challenges facing livestock meat production differ between countries in different geographic regions based on social, economic, cultural contexts and dietary habits
Microencapsulation de composés phénoliques extraits de feuilles, de fruits et de graines d'okra (Abelmoschus esculentus L.)
No full textInternational audienceSeveral plants rich in phenolic compounds have many uses in the food and pharmaceutical fields. However, after extraction, these active biomolecules are susceptible to degradation. Microencapsulation is a possible solution to prevent this rapid degradation. In this study, phenolic compounds from the okra Abelmoschus esculentus L’s leaves, fruits and seeds were extracted using microwave-assisted extraction and then microencapsulated via the spray drying technique using maltodextrin combined with pectin (in a ratio of 10:1) as an encapsulation material. The total phenolic content, DPPH scavenging and antimicrobial activities of okra extracts and encapsulated samples were evaluated to verify the encapsulation efficiency. Particle size distribution determination and scanning electron microscopy of the microcapsules were also carried-out. The ethanolic leaf extract showed higher significant levels of total phenolic compounds (162.46 ± 4.48 mg GAE/g DW), and anti-oxidant (75.65%) and antibacterial activities compared to those of other aqueous and ethanolic extracts from fruits and seeds. Furthermore, the spray-dried ethanolic leaf extract had the highest total phenolic content. However, the encapsulated ethanolic fruit extract had the highest percentage of DPPH scavenging activity (30.36% ± 1.49). In addition, antibacterial activity measurements showed that the addition of ethanolic and aqueous seed microcapsules provided a significant zone of inhibition against the bacterium Brochotrix thermosphacta (38 mm and 30 mm, respectively). Okra aqueous leaf microcapsules showed the smallest Sauter mean diameter values (7.98 ± 0.12 µm). These data are applicable for expanding the use of okra leaves, fruits and seeds as food additives and/or preservatives in the food industry.Plusieurs plantes riches en composés phénoliques ont de nombreuses utilisations dans les domaines alimentaire et pharmaceutique. Cependant, après extraction, ces biomolécules actives sont susceptibles de se dégrader. La microencapsulation est une solution possible pour empêcher cette dégradation rapide. Dans cette étude, les composés phénoliques des feuilles, fruits et graines du gombo Abelmoschus esculentus L ont été extraits par extraction assistée par micro-ondes, puis microencapsulés par la technique de séchage par atomisation en utilisant de la maltodextrine combinée à de la pectine (dans un rapport de 10:1) comme matériau d'encapsulation. La teneur phénolique totale, l'activité de piégeage du DPPH et les activités antimicrobiennes des extraits de gombo et des échantillons encapsulés ont été évaluées pour vérifier l'efficacité de l'encapsulation. La détermination de la distribution de la taille des particules et la microscopie électronique à balayage des microcapsules ont également été effectuées. L'extrait éthanolique de feuilles a montré des niveaux significatifs plus élevés de composés phénoliques totaux (162,46 ± 4,48 mg GAE/g DW), et des activités antioxydantes (75,65%) et antibactériennes comparées à celles d'autres extraits aqueux et éthanoliques de fruits et de graines. En outre, l'extrait éthanolique de feuilles séché par pulvérisation présentait la teneur phénolique totale la plus élevée. Cependant, l'extrait éthanolique de fruit encapsulé avait le pourcentage le plus élevé d'activité de piégeage de DPPH (30,36 % ± 1,49). En outre, les mesures de l'activité antibactérienne ont montré que l'ajout de microcapsules de graines éthanoliques et aqueuses fournissait une zone d'inhibition significative contre la bactérie Brochotrix thermosphacta (38 mm et 30 mm, respectivement). Les microcapsules aqueuses de feuilles d'okra ont montré les plus petites valeurs de diamètre moyen de Sauter (7,98 ± 0,12 µm). Ces données permettent d'élargir l'utilisation des feuilles, des fruits et des graines de gombo en tant qu'additifs alimentaires et/ou conservateurs dans l'industrie alimentaire
Consumer expectations for beef in the French region Auvergne-Rhône-Alpes
No full textSession 72, Poster 13International audienceIn France, beef consumption has been steadily decreasing for many years. The reasons are multifactorial, linked tothe: (1) controversial image of beef (its environmental impact, the competition between feed and food, the respectof animal welfare); (2) the modification of consumption patterns (decrease of daily time dedicated to cooking andeating); (3) its high price; and finally (4) its variable sensory quality. Thus, consumers are not always satisfied withthe organoleptic quality of beef. In this context, the scientific project OABov-AURA (2022-2024) was conducted. Anonline survey was carried out to study consumer expectations regarding the intrinsic and extrinsic qualities of beef, inthe region Auvergne-Rhône-Alpes (AURA) (the 2nd largest beef cattle breeding region in France). This study involved509 respondents, mostly female (62%), young (52%45 years old), students (28%) and executives (38%),with a good knowledge of farming (57%), and preferring to buy beef in butcher shops (31%). Among those surveyed,52% say that eating beef for pleasure is their primary motivation. The majority of consumers are not disappointedwith raw (86%) or cooked (58%) beef. Origin (89%), proximity (83%) and SIQO (Identification signs of quality andorigin) (82%) are the most important extrinsic criteria. However, taste, tenderness and freshness are the most intrinsicimportant criteria of beef for the respondents. Consumers also prefer meat that is bright red (50.7%) and rather fatty(57%). The two main reasons for the decrease in beef consumption are economic (28% of responses) and environmental(27%). In conclusion, it is important that consumers in the AURA region have access to a varied supply of meat inbutcher shops, of French origin and under quality signs