Chapter 9 Culture media for non-sporulating Gram positive, catalase positive food spoilage bacteria

The antiradical and antimicrobial activity of lignin and lignin-based films are both of great interest for applications such as food packaging additives. The polyphenolic structure of lignin in addition to the presence of O-containing functional groups is potentially responsible for these activities. This study used DPPH assays to discuss the antiradical activity of HPMC/lignin and HPMC/lignin/chitosan films. The scavenging activity (SA) of both binary (HPMC/lignin) and ternary (HPMC/lignin/chitosan) systems was affected by the percentage of the added lignin: the 5% addition showed the highest activity and the 30% addition had the lowest. Both scavenging activity and antimicrobial activity are dependent on the biomass source showing the following trend: organosolv of softwood > kraft of softwood > organosolv of grass. Testing the antimicrobial activities of lignins and lignin-containing films showed high antimicrobial activities against Gram-positive and Gram-negative bacteria at 35 °C and at low temperatures (0–7 °C). Purification of kraft lignin has a negative effect on the antimicrobial activity while storage has positive effect. The lignin release in the produced films affected the activity positively and the chitosan addition enhances the activity even more for both Gram-positive and Gram-negative bacteria. Testing the films against spoilage bacteria that grow at low temperatures revealed the activity of the 30% addition on HPMC/L1 film against both B. thermosphacta and P. fluorescens while L5 was active only against B. thermosphacta. In HPMC/lignin/chitosan films, the 5% addition exhibited activity against both B. thermosphacta and P. fluorescens.

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Antimicrobial Activity of neo-Clerodane Diterpenoids isolated from Lamiaceae Species against Pathogenic and Food Spoilage Microorganisms

Natural Product Communications ◽

10.1177/1934578x1501001101 ◽

2015 ◽

Vol 10 (11) ◽

pp. 1934578X1501001 ◽

Cited By ~ 1

Author(s):

Petko Bozov ◽

Tania Girova ◽

Natalia Prisadova ◽

Yana Hristova ◽

Velizar Gochev

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Food Spoilage ◽

Aerial Parts ◽

Spoilage Bacteria ◽

Microbial Strains ◽

Clerodane Diterpenoids ◽

Acetone Extracts ◽

And Staphylococcus Aureus ◽

Spoilage Microorganisms

Antimicrobial activity of nineteen neo-clerodane diterpenoids, isolated from the acetone extracts of the aerial parts of Scutellaria and Salvia species (Lamiaceae) were tested against thirteen strains belonging to nine different species of pathogenic and food spoilage bacteria Aeromonas hydrophila, Bacillus cereus, Escherichia coli, Listeria monocytogenes, Proteus vulgaris, Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella abony and Staphylococcus aureus as well as against two yeast strains belonging to species Candida albicans. Seven of the evaluated compounds scutalpin A, scutalpin E, scutalpin F, salviarin, splenolide A, splenolide B and splendidin demonstrated antimicrobial activity against used test microbial strains, the rest of the compounds were inactive within the studied concentration range. Among all of the tested compounds the highest antimicrobial activity was detected for scutalpin A against Staphylococcus aureus (MIC 25 μg/mL).

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