Bankova, V (2009) Chemical diversity of propolis makes it a valuable source of new biologically active compounds. Journal of ApiProduct  & ApiMedical Science, Vol 1 (2) 23-28. DOI:  10.3896/IBRA.4.01.2.01

Propolis with its diverse pharmacological activities and low toxicity has attracted the attention of modern scientists since about 50 years. However, propolis, or bee glue, has demonstrated remarkable chemical variability, which is a serious obstacle to its standardization and consequently, to its official acceptance into the main stream of our healthcare system. On the other hand, the variation in the chemistry of propolis from different ecosystems has made it a source of new biologically active molecules, mainly antioxidative, antibacterial and anticancer agents. The most important recent findings concerning bioactive molecules isolated from propolis are reviewed and discussed here.

Keywords: propolis/ caffeic acid phenethyl ester/ artepillin C/ prenylated benzophenones/ propolins

Bankova, V., Boudourova-Krasteva, G., Sforcin, J. M., Frete, X. and Kujumgiev, A. (1999) Phytochemical evidence for the plant origin of Brazilian propolis from Sao Paulo state. Zeitschrift für Naturforschung, section C, 54(5/6), 401-405.

                GC-MS analysis of propolis was compared with analyses for secretions from three plants that are thought to be propolis sources in this region. The results showed that Baccharis dracunculifolia is the main source. (The other plants were Araucaria angustifolia and Eucalyptus citriodora.) The antibacterial and antifungal activities of all 4 materials were also tested, and the most active were propolis and Baccharis leaf exudate. Accession date: 23 February 2000. Call number: 638.178. Library code: X. Language: En. Author address: Inst. of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria. Apicultural Abstracts from IBRA: AA824/00

propolis/Baccharis/antibacterial properties/antifungal properties/composition/Araucaria/Eucalyptus/Brazil.

Bankova, V., Christov, R., Popov, S., Marcucci, M. C., Tsvetkova, I. and Kujumgiev, A. (1999) Antibacterial activity of essential oils from Brazilian propolis. Fitoterapia, 70(2), 190-193.

                Essential oils extracted from propolis samples from Melipona compressites [M. compressipes], Tetragona clavipes and M. quadrifasciata anthidioides collected in Piaui and Parana States were tested for antibacterial activity using the modified diffusion method. The oils showed weak activity against Staphylococcus aureus 209, but were inactive against Escherichia coli. Accession date: 23 February 2000. Call number: 595.799. Library code: X. Language: En. Author address: Inst. of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Bl. 9, Acad. G. Bonchev str., 1113 Sofia. Apicultural Abstracts from IBRA: AA621/00

propolis/antibacterial properties/Brazil/Meliponinae/Melipona/Trigona/Staphylococcus/ Escherichia coli

Bankova, V. and Marcucci, M. C. (2000) Standardization of propolis: present status and perspectives. Bee World, 81(4), 182-188.

                Methods for the analysis of propolis and the determination of its biological activity are reviewed, as well as the identifiaction of plant sources. The possible standardization of propolis is discussed. Accession date: 26 January 2001. Call number: 638.178. Library code: Bj. Language: En. P Walker. Author address: Inst. of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria. Apicultural Abstracts from IBRA: AA261/02

propolis/analytical methods/composition/plants/standards/reviews.

Bankova, V., Popova, M., Bogdanov, S. and Sabatini, A. G. (2002) Chemical composition of European propolis: expected and unexpected results. Zeitschrift für Naturforschung, C, 57(5/6), 530-533.

                Ten propolis samples from Bulgaria, Italy and Switzerland were analysed by GC-MS. As expected, most samples displayed the typical chemical pattern of 'poplar' propolis: they contained pinocembrin, pinobanksin and its 3-O-acetate, chrysin, galangin, prenyl esters of caffeic and ferulic acids. Two samples differed significantly: one from the Graubünden Alpine region, Switzerland, which was rich in phenolic glycerides, and one from Sicily which contained only a limited number of phenolics and was rich in diterpenic acids. Accession date: 7 January 2003. Call number: 638.178. Library code: X. Language: En. Author address: Inst. of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria. Apicultural Abstracts from IBRA: AA1171/02

propolis/composition/Populus/Switzerland/Bulgaria/Italy.

Bankova, V. S., Castro, S. L. d. and Marcucci, M. C. (2000) Propolis: recent advances in chemistry and plant origin. Apidologie, 31(1), 3-15.

                Information on propolis constituents and plant sources of propolis, published since 1995, is reviewed. Publications on propolis of native South American stingless bees are also reviewed. Some aspects of the chemical standardization of propolis are discussed. Accession date: 2 May 2000. Call number: 638.178. Library code: Bj. Language: En, de, fr. Author. Author address: Inst. of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria. Apicultural Abstracts from IBRA: AA293/00

propolis/composition/Apis mellifera/Meliponinae/South America/phenolic compounds/terpenes/plants/standards.

Banskota, A. H., Nagaoka, T., Sumioka, L. Y., Tezuka, Y., Awale, S., Midorikawa, K., Matsushige, K. and Kadota, S. (2002) Antiproliferative activity of the Netherlands propolis and its active principles in cancer cell lines. Journal of Ethnopharmacology, 80(1), 67-73. DOI: doi:10.1016/S0378-8741(02)00022-3    

The MeOH extract of the Netherlands propolis showed promising antiproliferative activity toward highly liver-metastatic murine colon 26-L5 carcinoma with an EC₅₀ value of 3.5 μg/ml. Further, antiproliferative activity-guided purification of the MeOH extract led us to isolate four flavonoids (1-4), seven cinnamic acid derivatives (5-11) and two new glycerol derivatives (12, 13), whose structures were elucidated on the basis of spectral analysis. The isolated compounds were tested for their antiproliferative activity against murine colon 26-L5, murine B16-BL6 melanoma, human HT-1080 fibrosarcoma and human lung A549 adenocarcinoma cell lines. The benzyl (9), phenethyl (10) and cinnamyl caffeates (11) possessed potent antiproliferative activities with EC₅₀ values of 0.288, 1.76 and 0.114 μM, respectively, toward colon 26-L5 carcinoma. These caffeates were considered to be active constituents of the Netherlands propolis in their antiproliferative activity. The antioxidative activity of these caffeates may play an important role in their antiproliferative activities.

                Accession date: 7 January 2003. Call number: 638.178. Library code: X. Language: En. Author address: Dept of Natural Products Chemistry, Inst. of Natural Medicine, Toyama Medical and Pharmaceutical Univ., 2630-Sugitani, Toyama 930-0194, Japan. Apicultural Abstracts from IBRA: AA1172/02

propolis/cancer/antioxidant activity/Antiproliferative activity/ DPPH radical scavenging activity/ Benzyl caffeate/ Phenethyl caffeate/ Cinnamyl caffeate

Banskota, A. H., Tezuka, Y., Adnyana, I. K., Ishii, E., Midorikawa, K., Matsushige, K. and Kadota, S. (2001) Hepatoprotective and anti-Helicobacter pylori activities of constituents from Brazilian propolis. Phytomedicine, 8(1), 16-23.

                Methanol extract of propolis from various sources was tested on D-galactosamine /tumour necrosis factor-alpha (TNF-alpha)-induced cell death in primary cultured mouse hepatocytes. Hepatoprotective activity was found to be due to phenolic compounds including flavonoids, and 4 isolated flavonoids possessed stronger inhibitory activity than silibinin on TNF-alpha-induced cell death. Labdane-type diterpenes isolated from the extract also exhibited significant hepatoprotective activity. Moreover, these diterpenes and some prenylated phenolic compounds possessed antibacterial activity against H. pylori. Accession date: 17 December 2001. Call number: 638.178. Library code: X. Language: En. Author address: Dept of Natural Products Chemistry, Inst. of Natural Medicine, Toyama Medical and Pharmaceutical Univ., 2630-Sugitani, Toyama 930-0194, Japan. Apicultural Abstracts from IBRA: AA543/02

Helicobacter pylori/propolis/antibacterial properties/flavonoids/diterpenes/tumours/mice/medicinal properties.

Banskota, A. H., Tezuka, Y., Adnyana, I. K., Midorikawa, K., Matsushige, K., Message, D., Huertas, A. A. G. and Kadota, S. (2000) Cytotoxic, hepatoprotective and free radical scavenging effects of propolis from Brazil, Peru, the Netherlands and China. Journal of Ethnopharmacology, 72(1/2), 239-246.

                The 1,1-diphenyl-2-picrylhydrazyl (DPPH)-free-radical-scavenging activity, cytotoxicity and hepatoprotective activity of methanol and water extracts of 9 propolis samples were studied. The water extracts of 6 Brazilian and a Chinese propolis possessed stronger DPPH-free-radical-scavenging activity than the corresponding methanol extract, but the reverse was found for Netherlands and Peruvian propolis. The methanol extracts of all propolis samples possessed stronger cytotoxicity than the corresponding water extracts towards murine colon 26-L5 carcinoma and human HT-1080 fibrosarcoma cells. The hepatoprotective activity of Brazilian propolis, assessed as inhibition of D-galactosamine/tumour necrosis factor-alpha-induced cell death in primary cultured mouse hepatocytes, was generally stronger for the methanol extracts. Accession date: 4 April 2001. Call number: 638.178. Library code: X. Language: En. Author address: Dept of Natural Products Chemistry, Inst. of Natural Medicine, Toyama Medical and Pharmaceutical Univ., 2630-Sugitani, Toyama 930-0194, Japan. Apicultural Abstracts from IBRA: AA1211/01

propolis/Brazil/Peru/Netherlands/China/cytotoxicity/hepatoprotective properties.

Banskota, A. H., Tezuka, Y., Midorikawa, K., Matsushige, K. and Kadota, S. (2000) Two novel cytotoxic benzofuran derivatives from Brazilian propolis. Journal of Natural Products, 63(9), 1277-1279.

                Two novel benzofuran derivatives, propolis-benzofurans A (1) and B (2), were isolated from the methanol extract of Brazilian propolis, together with two known isoprenylated compounds (E)-3-[2,3-dihydro-2-(1- methylethenyl)-7-prenyl-5-benzofuranyl]-2-propenoic acid and (E)- 3-{4-hydroxy-3-[( italic~E roman~)-4-(2,3-dihydrocinnamoyloxy)-3-methyl-2- butenyl]-5-prenylphenyl}-2-propenoic acid. The structures of these compounds were elucidated; both exhibited mild cytotoxicity toward highly liver-metastatic murine colon 26-L5 carcinoma and human HT-1080 fibrosarcoma cells. Accession date: 3 December 2001. Call number: 638.178. Library code: wf. Language: En. Author address: Inst. of Natural Medicine, Toyama Medical and Pharmaceutical Univ., 2630-Sugitani, Toyama 930-0194, Japan. Apicultural Abstracts from IBRA: AA544/02

propolis/composition/benzofurans/cytotoxic properties/cancer/medicinal properties.

Bastos, E. M. A. F., Oliveira, V. D. C. and Soares, E. E. (2000) [Microscopic characterization of the green propolis produced in Minais Gerais State, Brazil]. Honeybee Science, 21(4), 179-180.

                Microscopic analyses of propolis extracts confirmed that the main source of 'green' propolis collected by honey bees was Baccharis dracunculifolia. Accession date: 19 February 2001. Call number: 638.178. Library code: Bj. Language: Ja, en. Author address: Fundacão Ezequiel Dias, R. Conde Pereira carneiro 80, 31310-520, Belo Horizonte, MG, Brazil. Apicultural Abstracts from IBRA: AA262/02

propolis/composition/Baccharis/plants/Brazil.

Bedascarrasbure, E. L., Maldonado, L. M., Alvarez, A. R., Horst, A. v. d. and Rodriguez, E. (2001) [Content of flavonoids in Argentinian propolis]. Honeybee Science, 22(2), 75-78.

                Total flavonoid content in 5 samples from different areas ranged from 3.6% to 12.3%; contents of individual flavonoids and phenols varied between samples. Accession date: 31 October 2001. Call number: 638.178. Library code: Bj. Language: Ja, en. Author. Author address: INTA EEA, UNCPBA, PO Box 11, 4132 Famailla Tucumain, Argentina. Apicultural Abstracts from IBRA: AA545/02

propolis/composition/Argentina/flavonoids/phenols