A new prenylflavonoid isolated from propolis collected in the Solomon Islands.

The new prenylflavonoid, solophenol A (1), together with three known compounds, bonannione A (2), sophoraflavanone A (3) and (2S)-5,7-dihydroxy-4'-methoxy-8-prenylflavanone (4), were isolated from propolis collected from Malaita Island in The Solomon Islands. The structure of each compound was determined by spectroscopic methods, including mass spectrometry and 2D NMR. Compound 1 exhibited potent 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity.

Identification of the plant origin of propolis from Jeju Island, Korea, by observation of honeybee behavior and phytochemical analysis.

Propolis collected on Jeju Island, Korea, contains characteristic components not present in propolis from other regions. Hence, the plant origin of the propolis from Jeju Island can be expected to be a novel plant. To identify the plant origin of this propolis, first we observed honeybee behavior, and found them collecting the resin from Angelica keiskei. Then comparative analyses of chemical and biological properties of the resin from the plant and propolis from hives of nearby apiaries were performed. Alcoholic extracts showed entirely identical HPLC profiles and closely similar antioxidant activities. These results indicate that A. keiskei is the plant origin of the propolis from Jeju Island, Korea.

Phytochemical and anti-inflammatory properties of Senegalese propolis and isolated compounds.

Propolis is a chemically complex resinous product collected from various plant sources by honeybees that has been used historically a traditional folk medicine in many parts of the world. The main constituents of propolis are beeswax and plant resins. We recently obtained Senegalese propolis, which, to our knowledge, has not been previously reported. The purpose of this study was to analyze the composition of Senegalese propolis and evaluate its anti-inflammatory activity. Ten known phenolic compounds with phenanthrene or stilbene skeletons were isolated. Nitric oxide (NO) production assay revealed that Senegalese propolis suppresses lipopolysaccharide (LPS)-stimulated production of NO in J774.1 cells in a dose-dependent manner. The anti-inflammatory potency of Senegalese propolis was higher than that of other previously reported propolis. Furthermore, the eight compounds isolated from Senegalese propolis showed high anti-inflammatory activity by inhibiting the LPS-induced expression of inducible NO synthase (iNOS). These results suggest that Senegalese propolis and its components have potential applications as anti-inflammatory agents.

Hawaiian propolis: comparative analysis and botanical origin.

Propolis is a resinous mixture of substances collected and processed from various botanical sources by honeybees (Apis mellifera). We recently obtained Hawaiian propolis, the study of which, to our knowledge, has not been reported. The purpose of this study was to analyze the composition of Hawaiian propolis and to identify its botanical origin. A comparative analysis of Hawaiian and Okinawan propolis and of the glandular trichomes on Macaranga tanarius fruit (the botanical origin of Okinawan propolis) was performed using reversed-phase high-performance liquid chromatography coupled with high resolution-electrospray mass spectrometry. Hawaiian propolis contained nine prenylflavonoids that were also isolated from Okinawan propolis. In conclusion, we suggest that the botanical origin of Hawaiian propolis is M. tanarius, the same as that of Okinawan propolis.

Identification of the phenolic compounds contributing to antibacterial activity in ethanol extracts of Brazilian red propolis.

The purpose of this study is to identify the quantity and antibacterial activity of the individual phenolic compounds in Brazilian red propolis. Quantitative analysis of the 12 phenolic compounds in Brazilian red propolis was carried out using reversed-phase high-performance liquid chromatography. The main phenolic compounds in Brazilian red propolis were found to be (3S)-vestitol (1), (3S)-neovestitol (2) and (6aS,11aS)-medicarpin (4) with quantities of 72.9, 66.9 and 30.8 mg g of ethanol extracts(- 1), respectively. Moreover, the antibacterial activities of each compound against Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa were evaluated by measuring the minimum inhibitory concentrations. In particular, compound 4 exhibited the most potent antibacterial activity among all the assayed compounds against selected bacteria, indicating that 4 is the most active compound in Brazilian red propolis extracts. Thus, Brazilian red propolis may be used as food additives and pharmaceuticals to protect against bacteria.

Solophenols B-D and solomonin: new prenylated polyphenols isolated from propolis collected from the Solomon Islands and their antibacterial activity.

Three new prenylated flavonoids, namely, solophenols B (1), C (2), and D (3), as well as a new prenylated stilbene, solomonin (4), were isolated from propolis collected from the Solomon Islands. In addition, 17 known compounds were identified. The structures of the new compounds were determined by a combination of methods, including mass spectrometry and NMR. These new compounds and several known compounds were tested for antibacterial activity against Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa. Most of them exhibited potent antibacterial activity. These findings may indicate that propolis from the Solomon Islands has potential applications as an ingredient in food additives or pharmaceuticals.