Phytochemical Analysis and Biological Evaluation of Selected African Propolis Samples from Cameroon and Congo

Abstract

The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their structures were elucidated on the basis of spectral evidence. Three triterpenes and two diprenyl-flavonoids were identified from Congo propolis, which has been investigated for the first time, while thirteen triterpenes, three diprenyl-flavonoids, two monoterpenic alcohols and one fatty acid ester have been identified from Cameroon propolis samples. To our knowledge, the identified diprenyl-flavonoids, as well as five of the isolated and determined triterpenes, are reported for the first time in propolis. Moreover, the total polyphenol content was estimated in all extracts and the antimicrobial activities of all four extracts were studied against six Gram-positive and-negative bacteria and three pathogenic fungi, showing an interesting antibacterial profile.

Biological Properties and Therapeutic Applications of Propolis

“…In subtropical eastern Australia, pentacyclic triterpenoids and C ‐prenylated flavonoids, including abyssinoflavanone VII, propolin C and nymphaeol C, were identified (Massaro et al ., ). In Africa, three triterpenes and two diprenyl‐flavonoids were identified in Congo propolis, while thirteen triterpenes, three diprenyl‐flavonoids, two monoterpenic alcohols and one fatty acid ester have been identified in Cameroon propolis samples (Papachroni et al ., ).…”

Determination and Quantification of Gallic Acid in Raw Propolis by High-performance Liquid Chromatography–Diode Array Detector in Burundi

“…Previous studies conducted in sub-Saharan Africa have revealed propolis from this region to contain a high terpenoid content. 26,30 This has been confirmed by researchers, such as Zhang et al, 30 who investigated propolis samples from Uganda, Tanzania, Malawi, Zambia, South Africa, Cameroon, Nigeria, and The Gambia. They concluded that African propolis was rich in diterpenoids and triterpenoids.…”

“…Papakroni et al 26 found, for the first time, triterpenes, such as lupennon, β-amirin and lupeol, diprenyl-flavonoid lonchocarpol, and 6,8-diprenyl-eriodictyol in propolis samples from the Democratic Republic of Congo. Rushdi et al 27 found α-amyrin, β-amyrin, α-amyryl acetates, β-amyryl acetates, n-alkanes, n-alkenes, methyl n-alkanoates, and long-chain wax esters in propolis samples from Ethiopia.…”

“…Nevertheless, research on propolis in sub-Saharan Africa has shown that, in general, African propolis -like the propolis found in other tropical regions -is rich in terpenoids, including α-amyrine, β-amyrin, α-amyryl acetates, β-amyryl acetates, n-alkanes, n-alkenes, methyl n-alkanoates, and long-chain wax esters, among other compounds. [25][26][27][28][29][30] The price of propolis varies according to its source and quality. For example, Chinese propolis is offered for sale at about €25 to €50 euros per kg, while the Brazilian propolis is offered at higher prices (€100 to €150 euros per kg).…”

Chemical Profiles and Bioactive Molecules of Propolis: A Review

“…In addition, as contribution to the chemical profiling of selected samples of African propolis using dereplication (LC-HRMS), a sample of propolis from Cameroon was proven to be significantly rich in triterpenoids [21]. Another detailed study revealed three diprenyl-flavonoids, thirteen triterpenes, one fatty acid ester and two monoterpenic alcohols in Cameroonian propolis samples from Oku (North-west Region), Ngaoundal and Tekel (Adamawa region) [22].…”