Antimicrobial properties of lichen extracts against food-borne pathogens /
by Franzeska L. Mojica, Patricia Cecilia R. Peralta and Ma. Petrecia Sofia R. Sesma.
- Indang, Cavite : Cavite State University- Main Campus, 2015.
- ix, 42 pages : illustrations ; 28 cm.
Research Study (Science High School) Cavite State University
Includes bibliographical references.
College of Education (CED) College of Education (CED)
MOJICA, FRANZESKA MARIE L., PERALTA, PATRICIA CECILIA R, & SESMA, MA. PETRECIA SOFIA R. Antimicrobial Properties of Lichen Extracts against Food-borne Pathogens. Research Study (General Science Curriculum). Science High School, College of Education, Cavite State University, Indang, Cavite. April 2015. Adviser: Prof. Dulce L. Ramos.
The study entitled “Antimicrobial Properties of Lichen Extracts against Food- borne Pathogens” was conducted at the Biological Science Department Laboratory, College of Arts and Sciences, Cavite State University in Indang, Cavite and at the Singapore Pharmawealth Lifesciences Inc., Brgy. San Jose, San Pablo City, Laguna. The Study was conducted to describe the antimicrobial properties of lichen extracts. Specifically, this study aimed to: (1) determine the identity of the lichens; (2) determine the percent yield of the crude extracts in lichens; (3) determine which treatment is the best in terms of zones of inhibition of the pathogens; and (4) determine which type of bacteria can be greatly inhibited by lichen extract.
Lichens were collected from a private lot in San Pablo City, Laguna. Sample species were then sent to the University of the Philippines- Los Banos for identification. The lichens were then powdered and extracted using three different solvents- acetone, chloroform and ethanol. Pure lichen extracts were evaluated. The gram positive pathogens used in the bactericidal analysis were Bacillus subtilis, Listeria monocytogenes and Staphylococcus aureus, while the gram negative pathogens used were Escherichia coli and Salmonella typhimurium. The zones of inhibition on each pathogen were measured while the activeness of the lichen extracts were determined. Lichen species were identified as Ramalina nervulosa. Acetone lichen extract has the highest percent yield of 4.4%, followed by the chloroform lichen extract that yields 4%. Ethanol lichen extract has the lowest percent yield of 3.2%. Lichen extracts exhibited inhibitory activity against Bacillus subtilis. On the other hand, acetone lichen extract exhibited the greatest zone of inhibition compared to chloroform lichen extract and ethanol lichen extract.