ABSTRACT
OBJECTIVE: To analyze the antioxidant prenylflavonoids in different parts of Macaranga tanarius (M. tanarius) (Euphorbiaceae) including the leaf, petiole, stem, leaflet, flower and fruit (only in female plant), and to evaluate their antioxidant properties. METHODS: Methanol extracts of each part of M. tanarius were prepared and five prenylflavonoids in them were quantitatively analyzed using HPLC. The fruits from female plant were further separated into seed, pericarp, and glandular trichome. After the quantitative analyses of prenylflavonoids in each part of M. tanarius, antioxidant activity of the extracts was evaluated by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay. RESULTS: The leaf of M. tanarius contained two prenylflavonoids as main components in both male and female plants. Both flowers (male and female) contained five kinds of prenylflavonoids. In the petiole, stem and leaflet of both male and female plants, the prenylflavonoids were not detected or their amounts were very low. Five kinds of prenylflavonoids were detected in the seed, pericarp and glandular trichome of female M. tanarius. In particular, the glandular trichome had the highest level of total prenylflavonoids (235 mg/g of fresh plant). DPPH radical scavenging activity of all parts was more than 30%. CONCLUSIONS: We found that different parts of M. tanarius contained antioxidant prenylflavonoids. In particular, not only the glandular trichome but also the leaf contained prenylflavonoids, which indicated that M. tanarius may be developed as a functional plant, because the leaves of this plant can be easily collected.
Subject(s)
Antioxidants/analysis , Euphorbiaceae/chemistry , Flavonoids/analysis , Plant Components, Aerial/chemistry , Plant Extracts/analysis , Antioxidants/chemistry , Antioxidants/metabolism , Biphenyl Compounds/metabolism , Euphorbiaceae/metabolism , Female , Flavonoids/chemistry , Flavonoids/metabolism , Humans , Male , Picrates/metabolism , Plant Extracts/chemistry , Plant Extracts/metabolismABSTRACT
To directly identify the plant origin of propolis from Takebe-cho (Okayama, Japan), we observed the honeybee behavior. Honeybees scraped sap from the tree, Rhus javanica var. chinensis. We compared the constituents and radical-scavenging activity of this sap and propolis. Their chemical constituents and radical-scavenging activity were comparable. This indicates directly that the plant origin of this propolis is R. javanica var. chinensis.
Subject(s)
Rhus/classification , Animals , Bees/physiology , Chromatography, High Pressure Liquid , Japan , Plant Extracts/biosynthesis , Plant Extracts/chemistry , Rhus/chemistry , Rhus/metabolismABSTRACT
Propolis is a natural resinous product collected by honeybees from certain plants. It has gained popularity as a food and alternative medicine. Poplar and Baccharis are well known as the source plants of European and Brazilian propolis, respectively. However, the propolis from Okinawa, Japan, contains some prenylflavonoids not seen in other regions such as Europe and Brazil, suggesting that the plant origin of Okinawan propolis is a particular plant that grows in Okinawa. To identify the plant origin of Okinawan propolis, we observed the behavior of honeybees as they collected material from plants and caulked it inside the hive. Honeybees scraped resinous material from the surface of plant fruits of Macaranga tanarius and brought it back to their hive to use it as propolis. We collected samples of the plant and propolis, and compared their constituents by high-performance liquid chromatography with a photo-diode array detector. We also compared their 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity. The chemical constituents and biological activity of the ethanol extracts of the plant did not differ from those of propolis. This indicates directly that the plant origin of Okinawan propolis is M. tanarius.
