title: Quantitative Determination of Alkaloids in Lotus Flower (Flower Buds of Nelumbo nucifera) and Their Melanogenesis Inhibitory Activity.
abstract: A quantitative analytical method for five aporphine alkaloids, nuciferine (1), nornuciferine (2), N-methylasimilobine (3), asimilobine (4), and pronuciferine (5), and five benzylisoquinoline alkaloids, armepavine (6), norarmepavine (7), N-methylcoclaurine (8), coclaurine (9), and norjuziphine (10), identified as the constituents responsible for the melanogenesis inhibitory activity of the extracts of lotus flowers (the flower buds of Nelumbo nucifera), has been developed using liquid chromatography-mass spectrometry. The optimum conditions for separation and detection of these 10 alkaloids were achieved on a πNAP column, a reversed-phase column with naphthylethyl group-bonded silica packing material, with CH₃CN-0.2% aqueous acetic acid as the mobile phase and using mass spectrometry equipped with a positive-mode electrospray ionization source. According to the protocol established, distributions of these 10 alkaloids in the petal, receptacle, and stamen parts, which were separated from the whole flower, were examined. As expected, excellent correlations were observed between the total alkaloid content and melanogenesis inhibitory activity. Among the active alkaloids, nornuciferine (2) was found to give a carbamate salt (2'') via formation of an unstable carbamic acid (2') by absorption of carbon dioxide from the air.
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. morikawa@kindai.ac.jp.|Antiaging Center, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. morikawa@kindai.ac.jp.
authors.forename: Toshio
authors.initials: T
authors.lastname: Morikawa
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. kitagawa@koshiroseiyaku.co.jp.|Koshiro Company Ltd., 2-5-8 Doshomachi, Chuo-ku, Osaka 541-0045, Japan. kitagawa@koshiroseiyaku.co.jp.
authors.forename: Niichiro
authors.initials: N
authors.lastname: Kitagawa
authors.affiliation: Faculty of Pharmacy, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. g-tanabe@phar.kindai.ac.jp.
authors.forename: Genzoh
authors.initials: G
authors.lastname: Tanabe
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. ninomiya@phar.kindai.ac.jp.|Antiaging Center, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. ninomiya@phar.kindai.ac.jp.
authors.forename: Kiyofumi
authors.initials: K
authors.lastname: Ninomiya
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. okugawa_kameokanousan@koshiroseiyaku.co.jp.|Koshiro Company Ltd., 2-5-8 Doshomachi, Chuo-ku, Osaka 541-0045, Japan. okugawa_kameokanousan@koshiroseiyaku.co.jp.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Okugawa
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. motai@koshiroseiyaku.co.jp.|Koshiro Company Ltd., 2-5-8 Doshomachi, Chuo-ku, Osaka 541-0045, Japan. motai@koshiroseiyaku.co.jp.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Motai
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. i.regretful.168.strike-swallow@docomo.ne.jp.
authors.forename: Iyori
authors.initials: I
authors.lastname: Kamei
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. m-yoshikawa@leto.eonet.ne.jp.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yoshikawa
authors.affiliation: National Research Institute of Chinese Medicine, 155-1, Sec. 2, Linong St., Beitou District, Taipei 11221, Taiwan. lily@nricm.edu.tw.
authors.forename: I-Jung
authors.initials: IJ
authors.lastname: Lee
authors.affiliation: Pharmaceutical Research and Technology Institute, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. muraoka@phar.kindai.ac.jp.|Antiaging Center, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. muraoka@phar.kindai.ac.jp.|Faculty of Pharmacy, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. muraoka@phar.kindai.ac.jp.
authors.forename: Osamu
authors.initials: O
authors.lastname: Muraoka
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D002219:Carbamates / Q000737:chemistry; D045744:Cell Line, Tumor; D002853:Chromatography, Liquid; D004789:Enzyme Activation / Q000187:drug effects; D035264:Flowers / Q000737:chemistry*; D006801:Humans; D000070116:Lotus / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008543:Melanins / Q000096:biosynthesis; D008546:Melanoma, Experimental; D051379:Mice; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D002219:Carbamates; D008543:Melanins; D010936:Plant Extracts; D014442:Monophenol Monooxygenase; C070766:carbamic acid
keywords: Nelumbo nucifera; carbamate salt; lotus flower; melanogenesis inhibitor; nornuciferine; nuciferine; quantitative analysis