ÿþ<HTML><HEAD><TITLE>25º Congresso Brasileiro de Microbiologia </TITLE><link rel=STYLESHEET type=text/css href=css.css></HEAD><BODY aLink=#ff0000 bgColor=#FFFFFF leftMargin=0 link=#000000 text=#000000 topMargin=0 vLink=#000000 marginheight=0 marginwidth=0><table align=center width=700 cellpadding=0 cellspacing=0><tr><td align=left bgcolor=#cccccc valign=top width=550><font face=arial size=2><strong><font face=Verdana, Arial, Helvetica, sans-serif size=3><font size=1>25º Congresso Brasileiro de Microbiologia </font></font></strong><font face=Verdana size=1><b><br></b></font><font face=Verdana, Arial,Helvetica, sans-serif size=1><strong> </strong></font></font></td><td align=right bgcolor=#cccccc valign=top width=150><font face=arial size=2><strong><font face=Verdana, Arial, Helvetica, sans-serif size=1><font size=1>ResumoID:1051-1</font></em></font></strong></font></td></tr><tr><td colspan=2><br><br><table align=center width=700><tr><td>Área: <b>Fermentação e Biotecnologia ( Divisão J )</b><p align=justify><strong><P><STRONG><FONT SIZE=4>REDUCTION OF COSTS IN NISIN PRODUCTION USING DILUTED SKIMMED MILK IN BIOREACTOR</FONT></STRONG></P></strong></p><p align=justify><b><u>Luciana Juncioni de Arauz </u></b> (<i>FCF/USP</i>); <b>Angela Faustino Jozala </b> (<i>FCF/USP</i>); <b>Priscila Gava Mazzola </b> (<i>FCM/UNICAMP</i>); <b>Júlia Baruque-ramos </b> (<i>EACH/USP</i>); <b>Adalberto Pessoa Júnior </b> (<i>FCF/USP</i>); <b>Thereza Christina Vessoni Penna </b> (<i>FCF/USP</i>)<br><br></p><b><font size=2>Resumo</font></b><p align=justify class=tres><font size=2><P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US">Nisin is widely used natural food preservative due to its antimicrobial activity and has potential applications in numerous fields (pharmaceutical, veterinary and health care products). However, the high cost of producing nisin by batch cultures of <I style="mso-bidi-font-style: normal">L. lactis</I>, is a limiting factor. This study aims to optimize large-scale nisin production utilizing diluted skimmed milk as alternative growth media to reduce process costs and stimulate its use. </SPAN><I style="mso-bidi-font-style: normal"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US">Lactococcus lactis</SPAN></I><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US"> subsp. <I style="mso-bidi-font-style: normal">lactis</I> ATCC 11454 precultures were growth in 150 mL MRS broth for 36 h at 30ºC. It was poured into 1500 mL of diluted skimmed milk with 25% of standard concentration (2.27 g <SUB>total solids</SUB>) in 2L bioreactor (New Brunswick Scientific), at 30ºC for 52 h. The operation conditions were, 100 or 200 rpm, and 0.5 L. min<SUP>-1</SUP> air flow or without air injection. The nisin activity expressed in culture media was quantified by agar diffusion assay, utilizing <I style="mso-bidi-font-style: normal">Lactobacillus sakei</I> ATCC 15521 as sensitive indicator microorganism. </SPAN><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US">The highest and the lowest nisin activity were detected in conditions with 0.5 L.min</SPAN><SUP><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US">-1</SPAN></SUP><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US"> air injection: (i) 100rpm, after 16 h (8.38x10<SUP>3</SUP> AU.mL<SUP>-1</SUP>) of cultive, (ii) 200rpm, after 20h (1.04x10<SUP>3 </SUP>AU.mL<SUP>-1</SUP>) of microbial growth. On the other hand, the assays without air injection reached the best nisin activity after 36 h/100rpm (2.0x10<SUP>3</SUP> AU.mL<SUP>-1</SUP>) and 12 h/200rpm (2.88x10<SUP>3</SUP> AU.mL<SUP>-1</SUP>) of batch cultures. The results showed that the dilution of skimmed milk supplied nisin expression from cells into media in a short-time process (16h). From an industrial point of view, diluted </SPAN><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US">skimmed milk can be used as an alternative economical medium for production of this biomolecule high value-added.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US"><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US"><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US"><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US">Acknowledgments:<B style="mso-bidi-font-weight: normal"><SPAN style="mso-spacerun: yes">&nbsp; </SPAN></B>CNPq, FAPESP, CAPES and Instituto Adolfo Lutz (IAL/SP)<o:p></o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US"><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US"><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: normal; TEXT-ALIGN: justify"><SPAN lang=EN-US style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-bidi-font-family: Calibri; mso-ansi-language: EN-US"><o:p>&nbsp;</o:p></SPAN></P> <P>&nbsp;</P></font></p><br><b>Palavras-chave: </b>&nbsp;Nisin, Bioreactor, Skimmed milk, Batch cultures, Lactococcus lactis</td></tr></table></tr></td></table></body></html>