Development of simple separation method of lactopholin from cheese whey and their functional evaluation

2000 Fiscal Year Final Research Report Summary

• Project/Area Number: 10556057
• Research Category: Grant-in-Aid for Scientific Research (B).
• Allocation Type: Single-year Grants
• Section: 展開研究
• Research Field: Zootechnical science/Grassland science
• Research Institution: Utsunomiya University
• Principal Investigator: KANNO Choemon Utsynomiya University, Agriculture, Professor, 農学部, 教授 (30011969)
• Co-Investigator(Kenkyū-buntansha): MOTOSHIMA Hideo Yotsuba Milk Co., Research Center, Senior researcher, リサーチセンター, 主任研究員 ; AMETANI Michiko Utsynomiya University, Agriculture, Research Associate, 農学部, 助手 (80240688) ; AZUMA Norihiro Utsynomiya University, Agriculture, Associate Professor, 農学部, 助教授 (30151062) ; KURIKI Hitoshi Yotsuba Milk Co., Research Center, Researcher, リサーチセンター, 主任研究員
• Project Period (FY): 1998 – 2000
• Keywords: bovine milk / lactophoein / cheese whey / emulsification / ultrafiltration / simple separation / lipoprotein lipase

Research Abstract

Lactophorin(LP)is a major glycoprotein in the proteose-peptone fraction of whey fraction from bovine milk and constituted of two major glycopeptides(27 and 17 kDa)with other 3 to 5 minor peptides. From high content and localization in hydrophobic amino acid residues on the basis of the primary structure of 27 k peptide in LP, it is considered that LP may have a higher emulsifying functionality. This study was to develop a simple isolation method of LP from whey of cheese manufacturing and to evaluate the emulsifying activity and inhibitory activity to milk lipoprotein lipase of the obtained LP specimen. The following results were obtained in this study.
1. We have established a simplified and economic isolation method of LP from cheese whey in the pilot plant scale. Cheese whey(363 kg)was concentrated to about 1/16 in its volume by passing through ultra-filter-membrane(corresponding to 500 k molecular weight)and reversed osmosis to about 1/60-70 of whey in volume, and then the concentrates containing LP were adjusted to pH4.0, heated for 30min at 95-100°C and centrifuged for 15min at 3000 rpm and the supernatant was freeze-dried. The obtained LP-enriched fraction was 54g.
2. The highly purified LP was prepared by gel filtration on Sephacryl S-300 of the isolated LP-enriched fraction.
3. LP-enriched fraction had the highest emulsifying activity, emulsion stability, specific surface areas and smallest median diameter of globules in emulsions prepared from 1% LP and 25% milk fat at pH7.0.
4. LP-enriched fraction and purified LP had the inhibitory activity of 52% and 70%, respectively, to milk lipoprotein lipase in partly injured milk fat globule and synthetic emulsion as the substrate. Increasing purified LP increased inhibitory effect to 90%.