title: Antibacterial Properties and Effects of Fruit Chilling and Extract Storage on Antioxidant Activity, Total Phenolic and Anthocyanin Content of Four Date Palm (Phoenix dactylifera) Cultivars.
abstract: Phoenix dactylifera or date palm fruits are reported to contain natural compounds that exhibit antioxidant and antibacterial properties. This research aimed to study the effect of fruit chilling at 4 °C for 8 weeks, extract storage at -20 °C for 5 weeks, and extraction solvents (methanol or acetone) on total phenolic content (TPC), antioxidant activity and antibacterial properties of Saudi Arabian P. dactylifera cv Mabroom, Safawi and Ajwa, as well as Iranian P. dactylifera cv Mariami. The storage stability of total anthocyanin content (TAC) was also evaluated, before and after storing the extracts at -20 °C and 4 °C respectively, for 5 weeks. Mariami had the highest TAC (3.18 ± 1.40 mg cyd 3-glu/100 g DW) while Mabroom had the lowest TAC (0.54 ± 0.15 mg cyd 3-glu/100 g DW). The TAC of all extracts increased after storage. The chilling of date palm fruits for 8 weeks prior to solvent extraction elevated the TPC of all date fruit extracts, except for methanolic extracts of Mabroom and Mariami. All IC50 values of all cultivars decreased after the fruit chilling treatment. Methanol was a better solvent compared to acetone for the extraction of phenolic compounds in dates. The TPC of all cultivars extracts decreased after 5 weeks of extract storage. IC50 values of all cultivars extracts increased after extract storage except for the methanolic extracts of Safawi and Ajwa. Different cultivars exhibited different antibacterial properties. Only the methanolic extract of Ajwa exhibited antibacterial activity against all four bacteria tested: Staphylococcus aureus, Bacillus cereus, Serratia marcescens and Escherichia coli. These results could be useful to the nutraceutical and pharmaceutical industries in the development of natural compound-based products.
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. azizan_12@siswa.um.edu.my.
authors.forename: Muhammad Azizan
authors.initials: MA
authors.lastname: Samad
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. hajarhashim93@gmail.com.
authors.forename: Siti Hajar
authors.initials: SH
authors.lastname: Hashim
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. hanom_ss@um.edu.my.
authors.forename: Khanom
authors.initials: K
authors.lastname: Simarani
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. jamilahsyafawati@um.edu.my.|Centre for Research in Biotechnology for Agriculture (CEBAR), Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. jamilahsyafawati@um.edu.my.
authors.forename: Jamilah Syafawati
authors.initials: JS
authors.lastname: Yaacob
mesh_terms: D000872:Anthocyanins / Q000737:chemistry / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D001409:Bacillus cereus / Q000187:drug effects; D003080:Cold Temperature; D004926:Escherichia coli / Q000187:drug effects; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification; D005638:Fruit / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D065749:Phoeniceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D012706:Serratia marcescens / Q000187:drug effects; D013048:Specimen Handling; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000872:Anthocyanins; D000900:Anti-Bacterial Agents; D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts
keywords: Phoenix dactylifera; antibacterial activity; antioxidant activity; storage; total anthocyanin content; total phenolic content