CELLULOSE CHEMISTRY AND TECHNOLOGY Cellulose Chem. Technol., 47 (1-2), 61-68(2013) IMPROVEMENT OF BACTERIAL CELLULOSE PRODUCTION BY ACEOBACTER XYILINUM DSMZ-2004 ON POOR QUALITY HORTICULTURAL SUBSTRATES USING THE TAGUCHI METHOD FOR MEDIA OPTIMIZATION. PART I ANGELA CASARICA, GHEORGHE CAMPEANU, * MIŞU MOSCOVICI, ALEXANDRA GHIORGHITA and VASILICA MANEA National Institute for Chemical Pharmaceutical Research and Development, Bucharest, Romania * University of Agricultural Sciences and Veterinary Medicine, Marasti Blvd., Bucharest Received October 19, 2011 The present paper investigates bacterial cellulose (BC) biosynthesis by Acetobacter xylinum DSMZ-2004, a source of microbial exploitation for cellulose obtainment, using poor quality apple extract and glycerol as carbon source. The objective of this research was to determine the influence of some significant biosynthesis medium parameters on bacterial cellulose production by enhancing the value of inadequate quality apples in a substrate combined with glycerol, leading to their superior conversion. Significant cost reduction is possible, along with an improvement in production efficiency and profitability, the lower limit of microbial cellulose cost being determined by the price of the raw matter used as a substrate. Inadequate quality apples and glycerol as a by-product of biodiesel production are not only cheap, but also abundant. It has been proven that bacterial cellulose production has been improved by applying the Taguchi experimental model of culture medium optimization, the maximum BC yield being of 8.6 g/L. Keywords: bacterial cellulose, poor quality apples, medium optimization, Taguchi method INTRODUCTION Most of the time, fruits are sold and consumed in their natural state, but most of the ones that are deteriorated or do not correspond to size standards, are processed into jams and sauces. Bad weather and other natural disasters lead to fruits presenting inadequate quality and, implicitly, to low prices and fruit waste. The great majority of these fruits end up being thrown away. Apples are popular fruits cultivated in our country, available most of the year. Considering their rich content of carbohydrates, proteins and oligoelements, we have in view to use such fruit of poor quality as a natural substrate for useful products fermentation. In comparison with other natural plant cellulose sources, bacterial cellulose (BC) is one of the most promising basic biological material, which presents many unique properties, including high purity and crystallization, high polymeri- zation degree, water absorption and retention capacity, high resistance to stretching and strong biological adaptability. 1-6 This type of material with wide application perspectives brings extraordinary economic benefits in various fields, such as food, textiles, paper, composite membranes, medicine, artificial skin and blood vessels, binders, diaphragms, speakers. 7-14 In recent years, the predominant applications of bacterial cellulose have been in the biomedical field, being extremely useful for wound dressings, artificial skin, dental implants, vascular grafts, covering catheter, membrane dialysis, coating for cardiovascular and cranial stent, membranes for guided tissue regeneration, tissue replacement, drug carrier for controlled release, vascular prosthetic devices, tissue engineering matrix and artificial blood vessels. 15