A micro-method for the estimation of oil content and fatty acid composition in seeds with special reference to cyclopropenoic acids

A micro-method is described for the routine estimation of oil content and fatty acid composition in seeds containing cyclopropenoic fatty acids (CPEFA) by determination of the total and component long-chain fatty acids. The oil was transmethylated without prior extraction using 1.17% sodium methoxide in methanol at 80°C for 45 min. The resultant fatty acid methyl esters were separated and measured by gas-liquid chromatography using a glass capillary column coated with Carbowax 20 M at 170°C. The method was shown to be applicable to a wide range of seeds including cottonseed (Gossypium hirsutum), kapok (Ceiba pentandra), paka (Urena lobata), baobab (Adansonia grandidieri and A. suarezensis). Individual seeds can be used with this method which needs only 50 to 150 mg for analysis. Results obtained with this micro-method were reproducible and good recoveries of oil and individual fatty acids were observed. The micro-method was compared for the determination of CPEFA (malvalic plus sterculic acids) to the nuclear magnetic resonance quantitation and gas-liquid chromography after derivatisation of CPEFA in more stable compounds.     

Fully automated attenuation measurement and motion correction in FLIP image sequences

Fluorescence loss in photobleaching (FLIP) is a method to study compartment connectivity in living cells. A FLIP sequence is obtained by alternatively bleaching a spot in a cell and acquiring an image of the complete cell. Connectivity is estimated by comparing fluorescence signal attenuation in different cell parts. The measurements of the fluorescence attenuation are hampered by the low signal to noise ratio of the FLIP sequences, by sudden sample shifts and by sample drift. This paper describes a method that estimates the attenuation by modeling photobleaching as exponentially decaying signals. Sudden motion artifacts are minimized by registering the frames of a FLIP sequence to target frames based on the estimated model and by removing frames that contain deformations. Linear motion (sample drift) is reduced by minimizing the entropy of the estimated attenuation coefficients. Experiments on 16 in vivo FLIP sequences of muscle cells in Drosophila show that the proposed method results in fluorescence attenuations similar to the manually identified gold standard, but with standard deviations of approximately 50 times smaller. As a result of this higher precision, cell compartment edges and details such as cell nuclei become clearly discernible. The main value of this method is that it uses a model of the bleaching process to correct motion and that the model based fluorescence intensity and attenuation estimates can be interpreted easily. The proposed method is fully automatic, and runs in approximately one minute per sequence, making it suitable for unsupervised batch processing of large data series.     

Agricultural biodiversity, nutrition, and health: making a difference to hunger and nutrition in the developing world

BACKGROUND: In spite of the strides made globally in reducing hunger, the problems of micronutrient deficiencies and coexisting obesity and related cardiovascular and degenerative diseases constitute a formidable challenge for the future. Attempts to reverse this trend with single-nutrient intervention strategies have met with limited success, resulting in renewed calls for food-based approaches. The deployment of agricultural biodiversity is an approach that entails greater use of local biodiversity to ensure dietary diversity. OBJECTIVE: To outline a new strategy proposed by the International Plant Genetic Resources Institute (IPGRI) that employs agricultural biodiversity as the primary resource for food security and health. METHODS: The authors carried out a meta-analysis to review and assemble existing information on the nutritional and healthful properties of traditional foods based on a diverse set of case studies and food composition and nutritional analysis studies. The methods highlight particular examples of foods where analysis of nutrient and non-nutrient composition reveals important traits to address the growing problems of malnutrition associated with the rise of chronic diseases. Finally, the authors analyze social, economic, and cultural changes that undermine the healthful components of traditional diets. RESULTS: Based on this multidisciplinary and comparative approach, the authors suggest a holistic food-based approach that combines research to assess and document nutritional and healthful properties of traditional foods, investigating options in which nutritionally valuable traditional foods can contribute to better livelihoods, and ways that awareness and promotional campaigns can identify healthful components of traditional diets that fit the needs of urban and market-oriented consumers. CONCLUSIONS: There is an urgent need for agricultural research centers, national agricultural research systems, universities, and community-based organizations to work together under a shared policy framework with the aim of developing a strong evidence base linking biodiversity, nutrition, and health. Although these initiatives are still ongoing, the gains realized in small-scale and local pilot efforts have encouraged IPGRI to work with local partners toward the implementation of scale-up efforts in various regions.