Print Email Facebook Twitter Harvesting Tool for Sustainable Taxoid Extraction from Taxus Species Title Harvesting Tool for Sustainable Taxoid Extraction from Taxus Species Author Banerjee, S. Contributor Wever, R. (mentor) De Jonge, A.C. (mentor) Ursem, W.N.J. (mentor) Faculty Industrial Design Engineering Department Design Engineering Date 2010-08-24 Abstract Taxoid is a member of a class of anticancer drugs derived from Yew (Taxus species) trees. This includes paclitaxel and docetaxel, which have found wide commercial exploitation. Currently taxoids are extracted from the taxus species through chemical extraction from needles, barks and through cell culture. These are chemical intensive processes and destroy the tree in the process of extraction too. The concentration of taxoids in the trees is also very low. Thus to treat one patient (2 g of paclitaxel), six 60-100 year old trees are required. This has led the species to the verge of extinction. Also the cost of the drug is sky high at 36.5 per mg. Cheaper alternative to the natural paclitaxel do exist in the market but they have a much lower spectrum of curing ability. Hence doctors prefer to use the natural drug. Two researchers, Marijnissen & Roos (1998), who had been working on electrospraying over years, reported that when they applied a strong electrostatic field near the needles of the taxus species, they start oozing out taxoids. Due to the very nature of the extraction process, they named it as: Milking of Taxus. This technique of taxoid extraction provides a promise of sustainable, cheap and non-destructive (to the tree) cancer treatment. In order to develop this into a commercially viable process, Bob Ursem, Director of Botanical garden, alongwith Marijnissen and other researchers have initiated a multidisciplinary approach. The team includes experts from Biology, Electronics and Industrial Design. The aim of this thesis was to design a harvesting mechanism by bringing in coherence the knowledge and expertise of all the experts. The thesis begins with an analysis of current scenario of development. The following aspects of the milking process were known at the beginning of the project: - Electrospray based extraction of taxoids is possible - Creation of a strong enough electric field causes milking - Insulating the electrode will eliminate sparks and short-circuits - Seasonal variation of taxoid content in different taxus species - Multiple extraction from the same branch is possible after regular intervals The following aspects of the milking process were still to be established: - How to convert lab setup to milk an actual hedge? - How to increase the yield of electrospray from each needle? - Optimum electrode shape - The value of electric field that causes milking - Relationship between current and spraying - Properties of insulation material - Hedge shaping - Relationship between temperature, humidity, wind and spraying - How to ensure all needles in the hedge participate in spraying? - Farm system required - Exact recuperating time for the tree - Long term effect of milking on the tree - How long a needle can be milked? Project achievements - Designed an electrode more efficient than the lab instrument – a straight plate electrode - Designed a manually operated harvester and tested it successfully in the lab and the garden - Economic analysis conducted - Software aided calculations and experiments helped to establish an optimum electric field value - Insulation material suitable to the process identified - Indications for optimum time for a single needle harvesting obtained Salient features of the designed harvester are: - No hedge trimming required - Visually 80-90% needles appear to be participating in milking - Geometry of electrode more efficient than straight plate lab equipment - Entire branch can be milked at one go - Different needle and branch configurations present in 9 species of taxus can be addressed - Sparks, discharges and needle burning eliminated Subject taxuscancer treatmentharvestersustainable To reference this document use: http://resolver.tudelft.nl/uuid:0500bcc5-c263-4fe3-a428-87beac9ac806 Embargo date 2011-08-24 Access restriction Campus only Part of collection Student theses Document type master thesis Rights (c) 2010 Banerjee, S.