title: Secondary metabolites constituents and antioxidant, anticancer and antibacterial activities of Etlingera elatior (Jack) R.M.Sm grown in different locations of Malaysia.
abstract: BACKGROUND
  Etlingera elatior is a well-known herb in Malaysia with various pharmaceutical properties.
  
  
  METHODS
  E. elatior flowers grown in three different locations of Malaysia (Kelantan, Pahang and Johor), were investigated for differences in their content of secondary metabolites (total phenolics [TPC], total flavonoids [TFC], and total tannin content [TTC]) as well as for their antioxidant, anticancer, and antibacterial properties. Phenolic acids and flavonoids were isolated and identified using ultra-high performance liquid chromatography (UHPLC). Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used to evaluate the antioxidant activities. The anticancer activity of extracts was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay.
  
  
  RESULTS
  When extracted with various solvents (aqueous and ethanolic), samples from the different locations yielded significantly different results for TPC, TFC, and TTC as well as antioxidant activity. Aqueous extracts of E. elatior flowers collected from Kelantan exhibited the highest values: TPC (618.9 mg/100 g DM), TFC (354.2 mg/100 g DM), TTC (129.5 mg/100 g DM), DPPH (76.4 %), and FRAP (6.88 mM of Fe (II)/g) activity with a half-maximal inhibitory concentration (IC50) of 34.5 μg/mL compared with extracts of flowers collected from the other two locations. The most important phenolic compounds isolated in this study, based on concentration, were: gallic acid > caffeic acid > tannic acid > chlorogenic acid; and the most important flavonoids were: quercetin > apigenin > kaempferol > luteolin > myricetin. Extracts of flowers from Kelantan exhibited potent anticancer activity with a IC50of 173.1 and 196.2 μg/mL against the tumor cell lines MCF-7 and MDA-MB-231 respectively, compared with extracts from Pahang (IC50 = 204.5 and 246.2 μg/mL) and Johor samples (IC50 = 277.1 and 296.7 μg/mL). Extracts of E. elatior flowers also showed antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa with minimal inhibitory concentrations (MIC) ranging from 30 to >100 μg/mL.
  
  
  CONCLUSIONS
  In general, therefore, based on the potent antioxidant and anticancer activity of flower extracts, it appears that E. elatior grown in the North-east of Malaysia (Kelantan) is a potential source of therapeutic compounds with anti-cancer activity.
authors.affiliation: Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia. alighasemzadeh@upm.edu.my.
authors.forename: Ali
authors.initials: A
authors.lastname: Ghasemzadeh
authors.affiliation: Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia. hawazej@upm.edu.my.
authors.forename: Hawa Z E
authors.initials: HZ
authors.lastname: Jaafar
authors.affiliation: Department of Nutrition & Dietetics, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. asmah@upm.edu.my.
authors.forename: Asmah
authors.initials: A
authors.lastname: Rahmat
authors.affiliation: Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia. ashkani.sadegh@upm.edu.my.|Department of Agronomy and Plant Breeding, Shahr-e- Rey Branch, Islamic Azad University, Tehran, Iran. ashkani.sadegh@upm.edu.my.
authors.forename: Sadegh
authors.initials: S
authors.lastname: Ashkani
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology; D001713:Biphenyl Compounds; D005419:Flavonoids; D035264:Flowers / Q000737:chemistry; D005707:Gallic Acid; D006801:Humans; D062385:Hydroxybenzoates; D019684:Magnoliopsida / Q000737:chemistry*; D008296:Malaysia; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000494:pharmacology; D010851:Picrates; D010936:Plant Extracts / Q000494:pharmacology*; D011794:Quercetin / Q000032:analysis; D013211:Staphylococcus aureus / Q000187:drug effects; D013634:Tannins / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D005419:Flavonoids; D062385:Hydroxybenzoates; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D013634:Tannins; D005707:Gallic Acid; C040015:myricetin; D011794:Quercetin; C004931:1,1-diphenyl-2-picrylhydrazyl; C017616:phenolic acid