• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.12
• /
• pp.1745-1752
• /
• 2010

This study was conducted to investigate the antimicrobial activity of 70% ethanol (EtOH) extract and the five fractions of the crude extract from Sasa borealis leaves against seven food poisoning bacteria, Staphylococcus aureus, Micrococus luteus, Listeria monocytogens, Bacillus subtilis, Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa. The yield of 70% EtOH extract was 11.4% and those of n-hexane, chloroform, ethyl acetate, n-butanol, and aqueous fractions were 3.0%, 1.1%, 0.6%, 1.3%, and 5.1%, respectively. The 70% EtOH extract and the four fractions except aqueous fraction demonstrated antimicrobial activity against all the seven food poisoning bacteria at a concentration of 0.5%, although it was less compared to benzoic acid. Minimal inhibitory concentration (MIC) of the 70% EtOH extract against all the food poisoning bacteria except S. aureus was $50{\mu}L$/disc. Moreover, chloroform fraction was $35{\mu}L$/disc against 3 food poisoning bacteria and $50{\mu}L$/disc against the other 4 food poisoning bacteria; ethyl acetate fraction was $50{\mu}L$/disc against all the food poisoning bacteria. In addition, n-butanol fraction was $50{\mu}L$/disc against all the food poisoning bacteria except S. aureus. Aqueous fraction, which did not show antimicrobial activity at 5%, was $200{\mu}L$/disc against only S. aureus and L. monocytogen. The 0.25%, and 0.5% of ethyl acetate fraction inhibited the growth of all the food poisoning bacteria 8 to 12 hours and 24 hours, respectively. These results indicate that the Sasa borealis leaves may be useful as a natural antimicrobial substance.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.3
• /
• pp.267-273
• /
• 2009

Antioxidative, antimicrobial activities and Raw 264.7 cell viability as cytotoxicity of various solvent extracts from leaf of Eriobotrya japonica Lindl. dried by different methods were investigated for processing as functional ingredient. In DPPH radical scavenging activity, RLE (80% EtOH extract of raw leaf) and FLE (80% EtOH extract of freeze-dried leaf) exhibited strong scavenging effect on $300{\mu}M$ DPPH radical solution (1.71 mg/mL and 2.11 mg/mL for RLE $SC_{50}$ and FLE $SC_{50}$). Also in nitric oxide scavenging activity, RLE and FLE showed strong activities (83.9% and 82.2% in 5 mg/mL sample concentration). Total phenolic compound contents of each extracts were found to be $73.7{\sim}215.4$ mg/g and RLE was showed the highest phenolic compound content. Also, total flavonoid contents were found to be $24.85{\sim}110.3$ mg/g and RLE was showed the highest flavonoid content. In antimicrobial activity, RLE was showed higher growth inhibition effect against all microbial strains. RLE, RLW (hot water extract of raw leaf), and FLW (hot water extract of freeze-dried leaf) exhibited strong antimicrobial activities against MRSA and S. aureus. In measurement of cytotoxicity by MTT assay, Raw 264.7 cell viabilities of 80% EtOH extracts showed better effect than water extracts. Especially viability of RLE was found be over 100% in every tested sample concentration.

• Food Science and Preservation
• /
• v.10 no.3
• /
• pp.421-426
• /
• 2003

Effects of acid, salt, heat treatment and natural antimicrobials on survival of E. coli O157:H7 CDF1, A. sobria CDF3 and S. aureus CDF2 isolated from surface of carcass in minced meat was investigated. The growth of E. coli O157:H7 CDF1 and A. sobria CDF3 inhibited in minced meat containing above 4％ NaCl but not in 1％ lactic acid. The growth of S. aureus CDF2 was not inhibited significantly by addition of 4％ NaCl but inhibited completely in minced meat containing 1％ lactic acid. Survival of A. sorbia CDF3 did not show any differences during storage at 4 and 10$^{\circ}C$. E. coli O157:H7 CDF10 and A. sobria CDF3 did not detect after heat treatment at 60$^{\circ}C$ for 10 min but S. aureus CDF2 decreased only 1 log after the same treatment. Viable cell of E. coli O157:H7 CDF1 decreased 2 log in TSB containing 0.5％ Oolong tea extract after incubation for 12 hr compared with control but A. sobria CDF3 and S. aureus CDF2 did not detect at the same condition. The growth of E. coli O157:H7 CDF1, A. sobria CDF3 and S. aureus CDF2 was not inhibited by addition of 0.3％ Oolong tea extract but inhibited by addition of 0.5％ Oolong tea extract in minced meat at 20$^{\circ}C$ for 24hr.