title: Antioxidant and antiproliferative activities of protein hydrolysate from the rhizomes of Zingiberaceae plants.
abstract: Plant proteins have been investigated for their antioxidant activities, but there are still no reports detailing the antioxidant activity levels of plants in the Zingiberaceae family, which are popular food agents and used in folklore medicine. In this study, the crude rhizome protein extract and associated pepsin/pancreatin protein hydrolysate of 15 plants in the Zingiberaceae family were screened using the DPPH method for antioxidant activity. The protein hydrolysate of C. zedoaria possessed the highest antioxidant activity (IC50of 25.7±6.3µg/mL), which was close to that of the reference ascorbic acid (IC50of 22.3±1.8µg/mL). After enrichment by Q Sepharose ion exchange chromatography using a five step elution gradient of increasing NaCl concentration (0, 0.25, 0.5, 0.75 and 1M), the fraction eluting in the 0.5M NaCl (F50) showed the highest antioxidant activity (IC50of 41.78±2.9µg/mL), and was found to have weak in vitro cytotoxicity against the HEP-G2 and SW620 cell lines (IC50of 200.8±11.8 and 241.0±9.3µg/mL, respectively), but not the BT474, CHAGO and KATO-3 cell lines. F50 had an estimated molecular weight by MALDI-TOF mass spectrometry of 12,400-12,800 Da.
authors.affiliation: Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, Thailand.
authors.forename: Kanok
authors.initials: K
authors.lastname: Inthuwanarud
authors.affiliation: Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, Thailand.
authors.forename: Polkit
authors.initials: P
authors.lastname: Sangvanich
authors.affiliation: The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, Thailand.
authors.forename: Songchan
authors.initials: S
authors.lastname: Puthong
authors.affiliation: The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, Thailand.
authors.forename: Aphichart
authors.initials: A
authors.lastname: Karnchanatat
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D001713:Biphenyl Compounds / Q000737:chemistry; D049109:Cell Proliferation / Q000187:drug effects*; D002852:Chromatography, Ion Exchange; D004305:Dose-Response Relationship, Drug; D056945:Hep G2 Cells; D006801:Humans; D020128:Inhibitory Concentration 50; D008970:Molecular Weight; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008517:Phytotherapy; D010851:Picrates / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010940:Plant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010946:Plants, Medicinal; D011492:Protein Hydrolysates / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D027343:Rhizome / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D030521:Zingiberaceae / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D001713:Biphenyl Compounds; D010851:Picrates; D010936:Plant Extracts; D010940:Plant Proteins; D011492:Protein Hydrolysates; C004931:1,1-diphenyl-2-picrylhydrazyl; D001205:Ascorbic Acid