{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/106241"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/106241","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Bacteriostatic and bactericidal effects of antibiotics on Bacteroides","abstract":"The bacteriostatic or bactericidal action of metronidazole, clindamycin, tetracycline, chloramphenicol, cefoxitin and penicillin were determined against sixteen Bacteroides fragilis strains and six B. thetaiotaomicron strains. Drugs were considered bactericidal when minimal bactericidal concentration (MBC) to minimal inhibitory concentration (MIC) ratios were less than or equal to four. As expected, metronidazole, cefoxitin and penicillin were bactericidal. However, clindamycin and chloramphenicol, which other investigators have considered as bacteriostatic antibiotics, were bactericidal. Tetracycline was irregularly bactericidal. When tested against Escherichia coli, tetracycline and chloramphenicol were bacteriostatic as reported by others. The MBCs of metronidazole, clindamycin and tetracycline were well within the clinically achievable levels of each drug. Death rate data confirmed these findings. With tetracycline, chloramphenicol and metronidazole MICs and MBCs increased as inocula sizes increased, however, with clindamycin and cefoxitin only MBCs increased. Clindamycin was administered to mice which had pure B. fragilis abscesses. Over 8 h cell numbers in the pus remained relatively constant even though, during this same period, the concentration of clindamycin in the pus was above the MBC of this drug for the strain used.","abstract_html":"The bacteriostatic or bactericidal action of metronidazole, clindamycin, tetracycline, chloramphenicol, cefoxitin and penicillin were determined against sixteen Bacteroides fragilis strains and six B. thetaiotaomicron strains. Drugs were considered bactericidal when minimal bactericidal concentration (MBC) to minimal inhibitory concentration (MIC) ratios were less than or equal to four. As expected, metronidazole, cefoxitin and penicillin were bactericidal. However, clindamycin and chloramphenicol, which other investigators have considered as bacteriostatic antibiotics, were bactericidal. Tetracycline was irregularly bactericidal. When tested against Escherichia coli, tetracycline and chloramphenicol were bacteriostatic as reported by others. The MBCs of metronidazole, clindamycin and tetracycline were well within the clinically achievable levels of each drug. Death rate data confirmed these findings. With tetracycline, chloramphenicol and metronidazole MICs and MBCs increased as inocula sizes increased, however, with clindamycin and cefoxitin only MBCs increased. Clindamycin was administered to mice which had pure B. fragilis abscesses. Over 8 h cell numbers in the pus remained relatively constant even though, during this same period, the concentration of clindamycin in the pus was above the MBC of this drug for the strain used.","abstract_has_math":false,"creators":["Veltri, Benjamin James"],"institution":"Virginia Polytechnic Institute and State University","degree_name":"M.S.","degree_level":"masters","degree_discipline":"Microbiology","degree_department":"Microbiology","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1978,"date_issued":"1978","date_published":"1978","updated_at":"2026-07-22T22:19:07Z","subjects":[],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/106241","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Microbiology"]},{"key":"dc:creator","label":"Author","values":["Veltri, Benjamin James"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2021-10-26T20:10:48Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2021-10-26T20:10:48Z"]},{"key":"dc:date.issued","label":"Date","values":["1978"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Polytechnic Institute and State University"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Microbiology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/106241"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The bacteriostatic or bactericidal action of metronidazole, clindamycin, tetracycline, chloramphenicol, cefoxitin and penicillin were determined against sixteen Bacteroides fragilis strains and six B. thetaiotaomicron strains. Drugs were considered bactericidal when minimal bactericidal concentration (MBC) to minimal inhibitory concentration (MIC) ratios were less than or equal to four. As expected, metronidazole, cefoxitin and penicillin were bactericidal. However, clindamycin and chloramphenicol, which other investigators have considered as bacteriostatic antibiotics, were bactericidal. Tetracycline was irregularly bactericidal. When tested against Escherichia coli, tetracycline and chloramphenicol were bacteriostatic as reported by others. The MBCs of metronidazole, clindamycin and tetracycline were well within the clinically achievable levels of each drug. Death rate data confirmed these findings. With tetracycline, chloramphenicol and metronidazole MICs and MBCs increased as inocula sizes increased, however, with clindamycin and cefoxitin only MBCs increased. Clindamycin was administered to mice which had pure B. fragilis abscesses. Over 8 h cell numbers in the pus remained relatively constant even though, during this same period, the concentration of clindamycin in the pus was above the MBC of this drug for the strain used."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["M.S."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Bacteriostatic and bactericidal effects of antibiotics on Bacteroides"]}]}],"canonical_facts":{"dc:contributor.department":["Microbiology"],"dc:creator":["Veltri, Benjamin James"],"dc:date.accessioned":["2021-10-26T20:10:48Z"],"dc:date.available":["2021-10-26T20:10:48Z"],"dc:date.issued":["1978"],"dc:description.abstract":["The bacteriostatic or bactericidal action of metronidazole, clindamycin, tetracycline, chloramphenicol, cefoxitin and penicillin were determined against sixteen Bacteroides fragilis strains and six B. thetaiotaomicron strains. Drugs were considered bactericidal when minimal bactericidal concentration (MBC) to minimal inhibitory concentration (MIC) ratios were less than or equal to four. As expected, metronidazole, cefoxitin and penicillin were bactericidal. However, clindamycin and chloramphenicol, which other investigators have considered as bacteriostatic antibiotics, were bactericidal. Tetracycline was irregularly bactericidal. When tested against Escherichia coli, tetracycline and chloramphenicol were bacteriostatic as reported by others. The MBCs of metronidazole, clindamycin and tetracycline were well within the clinically achievable levels of each drug. Death rate data confirmed these findings. With tetracycline, chloramphenicol and metronidazole MICs and MBCs increased as inocula sizes increased, however, with clindamycin and cefoxitin only MBCs increased. Clindamycin was administered to mice which had pure B. fragilis abscesses. Over 8 h cell numbers in the pus remained relatively constant even though, during this same period, the concentration of clindamycin in the pus was above the MBC of this drug for the strain used."],"dc:description.degree":["M.S."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/106241"],"dc:language.iso":["en"],"dc:publisher":["Virginia Polytechnic Institute and State University"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Bacteriostatic and bactericidal effects of antibiotics on Bacteroides"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Microbiology"],"thesis:degree_level":["masters"],"thesis:degree_name":["M.S."],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:07Z"}