為提升Serratia marcescens FM 115胞外黏性物質凍乾粉末(lyophilized extracellular mucilage, LEM)之產量，本研究改變培養基組成對S. marcescens FM 115生產LEM之產量與其蛋白質含量和總醣量變化進行探討。首先，將黏液篩選 基礎培養基（mucous screening basal broth, MSBB)組成中分別以不同糖類、氮源取 代以及額外添加不同之磷酸鹽和微量金屬離子等四種單一因子對S. marcescens FM 115 LEM之產量及其蛋白質含量和總醣量變化進行探討。結果發現分別以八 種不同之糖類取代MSBB中之蔗糖進行實驗，其中以5%麥芽糖取代組所得之LEM 產量最高，可達075 g/1，約為對照組的1.19倍，其LEM中的蛋白質含量和總醣量 分別為2.89%和78.15% ;其次，以八種常用之有機或無機氮源取代MSBB之 氮源[0.5% polypeptone (PP) + 0.1% yeast extract (YE)]進行實驗後，則發現 LEM 產量仍以控制組（MSBB中原氮源組合0.5% PP +0.1% YE)最佳；分別將三種磷 酸鹽 disodium- /3 -glycerophosphate(DSGP)、KH2P04 和 K2HP04 以不同濃度添力口 至MSBB之實驗中，結果以添加2% DSGP者可獲得最高的LEM產量0.79 g/1 (約 為對照組之1.25倍），而四種微量金屬離子Fe3+，Mn2+, Mg2+, Ca2+的添加試驗 中，則以添加1.0 mg/1 Fe3+組，可獲得LEM達0.73 g/1，而其LEM之蛋白量與 總醣量則前三组之結果無明顯差異(P <0.05)。根據上述結果，將黏液篩選基礎培 養基之组成調整為5%麥芽糖、0.5% PP + 0.1 %YE，採其他組成不變、額外添加 2% DSGP與1.0 mg/1 Fe3+的方式用於以下試驗，並名之為修飾黏液篩選基礎培養基。將S. marcescens FM 115以修飾黏液篩選基礎培養基進行培養，培養液起始pH 值7.2、振邊培養轉速為150 rpm及培養溫度26°C，經56小時培養之S. marcescens FM 115發酵所得之LEM產量可得到每公升發酵液中得到U2 g，為MSBB培養 者對照組(0.63 g/1)的1.78倍。

In order to increase the of lyophilized extracellular mucilage (LEM) yield from S. marcescens FM 115, the effects of change medium composition on the production of LEM and their protein and total carbohydrate content in the fermentation were investigated. First, eight saccharides, the five monosaccharides and three disaccharides studied, was used to substitute the caron source (sucrose) of mucous screening basal broth (MSBB). It was found that 5% maltose substitute showed the greatest LEM yield of 0.75 g/1 among nine sets and about 1.19 multiples of the control (MSBB) of 0.69 g/1, while the LEM had 78.15% and 2.89% sugar and protein content, respectively. Second，eight organic or inorganic nitrogen subjected to substitute the nitrogen source (sucrose) of MSBB were executed to study. The control (0.5% PP + 0.1% YE) gave the greast LEM yield in the eight sets of nitrogen source combinations tested. Third, three phosphates, disodium- (3 -glycerophosphate (DSGP), KH2P04 and K2HP04, were extra added to MSBB with different concentration, respectively to perform the experiment. 2% disodium- /3 -glycerophosphate (DSGP) resulted in the highest LEM yield of 0.79 g/1 among the three phophates at various concentration studied. Finally，four metal irons，Fe3+，Mn2+，Mg2+，Ca2+，with different concentration were also used additionally to MSBB to stuy, respectively. The 1 mg/1 Fe3+ set obtained the best result of LEM yield with 0.73 g/1 among the four metal ions tested. There was no significantly different in the sugar and protein content of LEM from those of the control.