Development and evaluation of the exopolysaccharide-producing lactic acid bacteria on the biosorption of Pb(II)

• Main Authors: YANG, CHIEH-SHENG, 楊杰陞
• Other Authors: TSAI, CHEN-CHIH
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/3s9w88

碩士 === 弘光科技大學 === 食品科技所 === 106 === Lead is common heavy metal which is toxic to humans. Widely utilized in many industries, it can contaminate the environment by being discharged into the air and water, and then enters the human body through the respiratory tract, food, or skin contact. Lead possesses the phenomena of bioaccumulation and biomagnification, and is also regarded as a persistent environmental pollutant. Lead half-life in blood is about 30 days and can remain in the skeletal system of years. Lead damages the human nervous, hematopoietic, renal, and endocrine systems. Biosorption is increasingly valued. Many biological absorbents (such a bacteria, algae, yeast and fungi) can be used to remove heavy metals. The purpose of this project is to screen strains of lactic acid bacteria (LAB) with high extracellular polysaccharide production from the strain library and evaluate the ability of LAB to absorb and eliminate heavy metals and lead (II). We further evaluate the ability of LAB to probiotic properties. The results showed the strain screened by the strains library which ability to produce extracellular polysaccharides and the amount of biomass. Used eight kinds of disks for antibiotic susceptibility tests, the results showed three strains of lactic acid bacteria were not resistant to Neomycin, Kanamycin and Streptomycin. Through API 50, PCR identification, the results from analysis were identified as Pediococcus acidilactici. The adhesion of intestinal epithelial cells assays showed the strain 17064 exhibited stronger adherence to the Caco-2 cell line. The results of the binding assays by three bacteria scavenging lead (II) ranged from 14.09 ~ 14.56 %. The lactic acid bacteria powders scavenging ability was better than bacteria. The results showed scavenging capability being 42.55 ~ 48.69 % The strains screened in this test show that the LAB have the potential to bind to metals, prevent them from entering the body and protect the host.