Screening for natural inhibitors of penicillinase by copolymerization of hydrolyzed starch or glycogen in sodium dodecylsulfate polyacrylamide gels for detecting penicillinase activity

Wen Li Liang, Hui Man Huang, Rong Dih Lin, Wen Chi Hou

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6 Citations (Scopus)


The 0.08% hydrolyzed starch or glycogen were copolymerized in 7.5% or 10% sodium dodecylsulfate polyacrylamide gels. After electrophoresis and SDS removal, the commercial penicillinase in gels was reacted with penicillin G (100 mg in 50 mL, 0.1 M phosphate buffer, pH 7.0) for 30 min and then stained with 0.6% I 2 in 6% KI solutions. The clear zone of penicillinase activity bands stood out against purple or orange-red backgrounds, respectively, for hydrolyzed starch or glycogen used. This activity staining method was used successfully to detect commercial penicillinase activities from Bacillus cereus and the cultured methicillin-resistant Staphylococcus aureus ATCC 33591 strain. This activity staining method was also applied to penicillinase natural inhibitor screenings. It was found that anthraquinone-related compounds, such as aloe-emodin, emodin and rhein, could inhibit penicillinase activity. This fast and sensitive method can be used in the process of penicillinase purification, characterization and inhibitor screening.

Original languageEnglish
Pages (from-to)187-191
Number of pages5
JournalBotanical Bulletin of Academia Sinica
Issue number3
Publication statusPublished - Jul 2003



  • Activity staining
  • Anthraquinone
  • Copolymerization
  • Penicillinase

ASJC Scopus subject areas

  • Plant Science

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