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L'huile de ricin est extraite du haricot de la plante tropicale Ricinus communis. Ses applications sont multiples soit dans le domaine industriel ou cosmétique. Toutefois, ses effets oculaires sont mal connus. L'objectif de ce travail est d'étudier à travers ce cas et la revue de la littérature, la toxicité oculaire de l'huile de ricin. Nous rapportons le cas d'une patiente de 32 ans sans antécédents pathologiques particuliers, admise aux urgences pour œil rouge douloureux après application d'huile de ricin à but esthétique (favoriser la repousse des sourcilles). L'examen ophtalmologique trouve une atteinte oculaire bilatérale faite de kératite ponctuée superficielle diffuse avec une inflammation conjonctivale responsable d'une baisse de l'acuité visuelle, le reste de l'examen est normal. La patiente était mise sous collyres et pommade antibiotiques, des larmes artificielles et des soins biquotidiens. L'évolution était marquée par une amélioration totale des signes oculaires sans séquelle. Les applications de l'huile de ricin dans le domaine industriel ou cosmétique sont multiples, toutefois, peu d'études ont été publiées concernant la toxicité oculaire à l'huile de ricin, la plupart des auteurs démontrent peu d´effets toxiques oculaire. Cependant cette observation illustre une atteinte oculaire grave justifiant l'intérêt de la prévention.

Seed oil of Castor bean (Ricinus communis L) grown in Morocco were analyzed for their main chemical composition and for their oxidative stability. Gas chromatography revealed that the major fatty acids were ricinoleic, linoleic, and oleic acids (75.0%, 9.7%, and 7. 7% respectively). Seed oil was also found to be rich in sterols (2210 mg/kg) with a predominance of β-sitosterol (1041 mg/kg). The tocopherols marker δ-tocopherol accounted for 43.1 mg/kg. Oxidative stability of castor oil was measured at 110 °C at the air flow rate of 20 L/hw, castor oil was more stable than many other oils with 35.5 h. The results achieved suggest that the castor bean might be an important source of vegetable oil for industrial uses., Moroccan Journal of Chemistry, Vol 4, No 2 (2016)

An enzymatic membrane reactor based on an enzymatic membrane elaborated by immobilizing a lipase on a ceramic support was used to perform interesterification between castor oil triglycerides and methyl oleate. As substrates solution is highly viscous, viscosity was reduced by injecting supercritical CO2. After the validation of the concept, the influence of different operating parameters as regards performance has been checked. The effect of the pore size of the ceramic support on which the enzyme is deposited has been looked at. Operating pressure was proved to be a key parameter as it highly influences productivity. The objective of this work is to report attractive results on this process which opens interesting prospects in a field where at the present time there are very few valuable technologies. © 2007 Elsevier B.V. All rights reserved.

A chemoenzymatic process for the production of structured triacylglycerols (TAG) containing CLA at sn2 position and lauric acid at external ones is proposed. First, castor bean oil was chemically dehydrated and isomerised to obtain a new modified oil with very high proportion of CLA (>95%). Then, this new oil was used for enzymatic transesterification allowing the grafting of lauric acid at external positions of the TAG backbone by using 1,3 regioselective enzymes. Among these, Aspergillus niger lipase was not satisfactory giving very low lauroyl incorporation (

γ-Decalactone production from ricinoleic acid biotransformation by Yarrowia lipolytica has drawn the attention of many authors and, in the last years, molecular and physiological developments were made through the use of engineered strains in novel culture conditions. The purpose of this work was to monitor the performance of modified Y. lipolytica strains in their lipid metabolism specifically at the β-oxidation pathway (MTLY40-2P strain, disrupted in the native genes POX2-5 and expressing an ectopic Aox2p-encoding gene) or at the triglyceride hydrolysis (JMY3010 strain, Lip2p overexpressed) using castor oil as substrate, in a lab-scale bioreactor. Using step-wise fed-batch cultures of MTLY40-2P strain, a γ-decalactone concentration of 7 g L−1 was reached. γ-Decalactone reconsumption was prevented and hydroxylactone production was reduced by Y. lipolytica MTLY40-2P strain. Moreover, substantial increase in the initial rate of aroma production was obtained with strain overexpressing LIP2 gene due to the fast hydrolysis of castor oil., Project ‘BioInd – Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028’ co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER and FCT Strategic Project PEst-OE/EQB/LA0023/2013.

Correspondance : villeneuve@supagro.inra.fr; International audience; The possibility of combining dehydration and isomerization of castor bean oil as a means to obtain CLA as TAG forms was studied.First, dehydration was carried out using various catalysts and reaction parameters. Best results were obtained using phosphoric acid (0.1% w/w) at 280°C for 5 h. Under such conditions, satisfactory proportions of CLA were obtained (54% of total FA) with a majority of 9-cis, 11-trans isomer (61% of total CLA). Other catalysts such as bisulfate-bisulfite, sulfuric acid, tungstic and phosphotungstic acids, or resins and zeolites were also tested. With the exception of resins and zeolites, these catalysts also led to CLA production but in limited amounts in comparison with phosphoric acid. In a second step, an isomerization reaction was carried out to transform the residual nonconjugated linoleic acid also produced during dehydration into CLA. Using Wilkinson catalyst [RhCl(PPh3)3] in ethanol solvent, dehydrated castor bean oil was isomerized in high yields (>98%), allowing a complete disappearance of nonconjugated linoleic acids. The resulting dehydrated/isomerized oil contained more than 87% CLA with the 9-cis, 11-trans isomer being predominant (40% of CLA fraction). Finally, urea fractionation was also applied on dehydrated/isomerized castor bean oil FA to obtain FFA products containing about 93% CLA

La présente invention concerne un procédé de préparation d'ester d'acide ricinoléique à partir d'une huile végétale pure en mélange, notamment l'huile de ricin, ledit procédé comprenant au moins une étape de transestérification enzymatique réalisée en présence d'un alcool léger et au moyen d'une lipase typosélective, et conduisant à l'obtention d'une fraction enrichie en ester d'acide riciloléique. Le procédé de production d'ester d'acide ricinoléique selon l'invention comprend les étapes suivantes : i) une première réaction de transestérification effectuée en présence d'un alcool léger et de la lipase extraite de Geotrichum candidum, conduisant à l'obtention d'un mélange M comprenant des mono-, di- et triglycérides d'AR, esters d'acides gras autres que l'AR, alcool ; ii) une étape de séparation dudit mélange M en au moins deux fractions, dont une fraction A enrichie en glycérides d'AR, et une fraction B riche en esters d'acides gras autres que l'AR ; iii) une étape de transformation desdits glycérides d'AR en esters d'AR formant une fraction C riche en esters et une fraction en alcools.

International audience; Objective: The present study was performed to evaluate the preventive and curative antidiarrheal effects of the methanol extract, fractions and compound from the stem bark of Trilepisium madagascariense in rats. Materials and Methods: The methanol extract from the stem bark of T. madagascariense, its fractions (n-hexane, ethyl acetate, n-butanol and aqueous residue) and compound (obtained from further column chromatography of the ethyl acetate fraction) were evaluated for the antidiarrheal activity in rats. These test samples (at 100, 200 and 400 mg/kg for the extract and fractions and 2.5 mg/kg for compound) were assayed on the latent periods, purging indices and fecal frequencies in castor oil-induced diarrhea. Gastrointestinal transit and castor oil-induced enteropooling assays were conducted. Shigella-induced diarrhea was assayed. Blood chemistry and fecal Shigella load were examined. Results: The fractionation of the ethyl acetate fraction from the methanol extract of T. madagascariense afforded a known compound [ isoliquiritigenin (1)]. Compound 1 increased the latent period of diarrhea induction (179.40 min) compared to the saline control (60.80 min). The purging indices, fecal frequencies and intestinal enteropooling decreased with an increase in the dose of test samples. The blood cell counts, sera creatinine and fecal Shigella load decreased significantly (P

The goal of this study was to produce conjugated linoleic acid (CLA) monoacylglycerols (MAGs). A chemicoenzymatic process was employed starting from castor bean oil, which was chemically dehydrated and isomerized to obtain new modified triacylglycerols (TAGs) with a very high proportion of CLA fatty acids (>95%). Such TAGs were then used in enzymatic glycerolysis reaction using Candida antarctica B lipase at 55C in tert-butyl alcohol as a solvent. The effect of enzyme load and substrate molar ratio on the production yield of MAGs was evaluated and optimized using response surface methodology with a two-factor and three-level factorial design. A satisfactory linear correlation existed between experimental results and predicted values (R2 = 0.97 and R2adj. = 0.94). Using the contour plot generated from the model for MAG production yield, optimum parameters could be obtained corresponding to an 11/1 glycerol/TAG molar ratio and an enzyme load of 2% (% w/w of both substrates). (Resume d'auteur)

International audience; This study deals with the enzymatic modification of vegetable oils with the help of a newreactor design. Basically, the newreactor is a porous membrane contactor along and through which substrates are flowing. It is constituted from an enzymatic membrane and uses supercritical carbon dioxide (SC CO2) to fluidify the highly viscous substrates. The interesterification between castor oil triglycerides and methyl oleate catalysed by a lipase was chosen as a model reaction. It was preliminary tested and characterized in a batch reactor. Then the feasibility of the new process was demonstrated on a cross-flow filtration unit operating under SC CO2 conditions. The stability of the immobilized enzymes was checked and the influence of the transmembrane pressure on the reaction rate was observed.

Membranes with specific enzymatic activities and low pore sizes (a few nanometers) have been recently developed at the European Membrane Institute. They represent "natural" assemblies of multiple microreactors placed in parallel, on which it is easy to favour the meeting between substrates -that one can force to cross the pores using the transmembane pressure- and catalyst -deposited onto the surface of material-. One can thus optimise the performance of reactions, as demonstrated with various low viscosity solvents (water, organic or even supercritical CO2 solutions). With highly viscous liquids such as oils, classical filtration is much more difficult. In this work the idea to decrease oil viscosity by injecting supercritical CO2 following a technique recently developed by the French Nuclear Commission, and then to modify oil characteristics through an active membrane, has been tested. The interesterification between castor oil triglycerides (TG) and methyl oleate, using a lipase as catalyst, in the presence of SC CO2 has been chosen as model system. A specific analytic method has been set up which uses planar chromatography for product separation, and clearly shows disappearance of methyl oleate as well as formation of methyl ricinoleate. The first experimental results make it possible to validate the new concept and show that the technology opens very interesting prospects for the biotransformation of biological products with a high viscosity. (Texte intégral)

Le CIRAD-FLHOR a été sollicité par l'ONUDI à participer à INDIA INVESMART, Forum International des Investissements Industriels, car il venait d'initier, en collaboration avec l'INRA et l'Université de Nottingham, la première collaboration de Recherche et Développement dans le domaine de la technologie fruitière avec l'un des plus importants centres de recherches indiens : le CFTRI (Central Food Technological Research Institute). Ce rapport dresse l'état de l'Industrie agro-alimentaire en Inde : libéralisation du secteur, production agricole fruitière et légumière (produits frais et transformés), potentiel humain, biens d'équipements, organisations régionales de transferts en Recherche et Développement, transformation de grains, brasserie et boissons alcoolisées. Un chapitre est consacré aux très nombreux contacts établis avec les industriels indiens de l'agro-alimentaire sur la base des projets identifiés par l'ONUDI. Ces contacts ont été essentiellement des demandes de coopération en agronomie et en technologie : banane, orange, ananas, mangue, champignons, séchage raisin, chimie huiles essentielles, distillation, huile de ricin, agronomie et technologie

Problématique : Un grand nombre des transferts prénatals de la maison de naissance de la Roseraie est dû à une absence de mise en travail chez les femmes enceintes, suite à une rupture prématurée des membranes à terme ou lors d’un dépassement de terme. Les sages-femmes utilisent régulièrement l’huile de ricin pour favoriser la mise en travail mais son efficacité et son utilisation sont contestées à travers le monde. Objectif : Trouver des preuves Evidence-Based Medicine (EBM) quant aux effets thérapeutiques et indésirables de l’huile de ricin, ainsi que ses modalités d’utilisation. Méthode : Une revue de littérature est effectuée à partir de 7 articles sélectionnés depuis les bases de données CINAHAL, MIDIRS, PUBMED et diverses lectures grises. Résultats : L’efficacité de l’huile de ricin dans le cadre de l’aide à la mise en travail est globalement reconnue mais les résultats ne sont pas unanimes. En effet, les auteurs ne s’accordent pas sur la fréquence des effets indésirables maternels et foetaux. Conclusion : En pratique, l’huile de ricin pourrait être proposée à des femmes enceintes menant une grossesse à bas risque, en les informant de l’état actuel des recherches et des effets indésirables potentiels. Des études supplémentaires sont requises afin d’étayer les connaissances sur l’efficacité et la sécurité de l’huile de ricin. Il nous semblerait pertinent de réaliser ces nouvelles études en uniformisant leurs critères d’évaluation, pour permettre une comparaison et ainsi obtenir des résultats plus significatifs.