Chemical Composition and Pharmacological Effects of Geopropolis Produced by Melipona quadrifasciata anthidioides

Analysing chemical composition and antimicrobial activity of geopropolis from Melipona scutellaris: HPLC-DAD and in vitro/in silico investigations

This study evaluated the chemical profile, antimicrobial activity, and the presence of potentially toxic elements in geopropolis extracts produced by Melipona scutellaris in the Recôncavo region of Bahia, Brazil. It was found that the major chemical compounds belong to the class of phenolic compounds, with emphasis on the presence of gallic acid. In this study, no potentially toxic elements were found in the analysed geopropolis. Regarding the antimicrobial potential, gram-positive bacteria were susceptible to the action of geopropolis extract at concentrations of 0.25 to 2.5 mg.mL-1, highlighting its microbiological activity against Streptococcus mitis (ATCC 00456) and Candida albicans (CCMB 251). Thus, this geopropolis extract can be used as a bacteriostatic rather than a bactericide. Our results suggest the potential for the economic and therapeutic use of M. scutellaris geopropolis, adding value to one of the meliponiculture products.

Recent Update on the Anti-Inflammatory Activities of Propolis

In recent years, research has demonstrated the efficacy propolis as a potential raw material for pharmaceuticals and nutraceuticals. There is limited report detailing the mechanisms of action of propolis and its bioactive compounds in relation to their anti-inflammatory properties. Thus, the aim of the present review is to examine the latest experimental evidence (2017-2022) regarding the anti-inflammatory properties of propolis. A systematic scoping review methodology was implemented. After applying the exclusion criteria, a total of 166 research publications were identified and retrieved from Scopus, Web of Science, and Pubmed. Several key themes related to the anti-inflammatory properties of propolis were subsequently identified, namely in relation to cancers, oral health, metabolic syndrome, organ toxicity and inflammation, immune system, wound healing, and pathogenic infections. Based on the latest experimental evidence, propolis is demonstrated to possess various mechanisms of action in modulating inflammation towards the regulatory balance and anti-inflammatory environment. In general, we summarize that propolis acts as an anti-inflammatory substance by inhibiting and downregulating TLR4, MyD88, IRAK4, TRIF, NLRP inflammasomes, NF-κB, and their associated pro-inflammatory cytokines such as IL-1β, IL-6, IFN-γ, and TNF-α. Propolis also reduces the migration of immune cells such as macrophages and neutrophils, possibly by downregulating the chemokines CXCL9 and CXCL10.

Chemical Composition and Biological Activity of Argentinian Propolis of Four Species of Stingless Bees

The chemical composition of propolis of four species of stingless bees (SLBs) from Argentina was determined, and its antibacterial and anticancer activity was evaluated on selected types of microbes and cancer cell lines. Volatile secretions of all propolis samples are formed by 174 C₂-C₁₅ organic compounds, mainly mono- and sesquiterpenes and their derivatives. The chromatograms of ether extracts showed 287 peaks, of which 210 were identified. The most representative groups in the extracts of various propolis samples were diterpenoids (mainly resin acids), triterpenoids and phenolic compounds: long-chain alkenyl phenols, resorcinols and salicylates. The composition of both volatile and extractive compounds turned out to be species-specific; however, in both cases, the pairwise similarity of the propolis of Scaptotrigona postica and Tetragonisca fiebrigi versus that of Tetragona clavipes and Melipona quadrifasciata quadrifasciata was observed, which indicated the similarity of the preferences of the respective species when choosing plant sources of resin. The composition of the studied extracts completely lacked flavonoids and phenolcarboxylic acids, which are usually associated with the biological activity and medicinal properties of propolis. However, tests on selected microbial species and cancer cell lines showed such activity. All propolis samples tested against Paenibacillus larvae, two species of Bacillus and E. coli showed biofilm inhibition unrelated to the inhibition of bacterial growth, leading to a decrease in their pathogenicity. Testing the anticancer activity of ether extracts using five types of cell cultures showed that all four types of propolis studied inhibit the growth of cancer cells in a dose- and time-dependent manner. Propolis harvested by T. clavipes demonstrated the highest cytotoxicity on all tested cell lines.

Propolis of stingless bees: A phytochemist's guide through the jungle of tropical biodiversity

BACKGROUND

Stingless bees (Meliponini), like honeybees Apis mellifera, collect plant resins in order to produce propolis (cerumen, geopropolis). This type of propolis has long been used in traditional medicine in Mexico, Brazil, Argentina, India, and Vietnam, as a remedy for improving health and treating various diseases. The scientific and commercial interest in stingless bee propolis has been steadily increasing over the last few years. The new and growing knowledge in this field requires systematising, as a basis for further work. Recent reviews of Meliponini propolis deal only with the South American and Mesoamerican species, while reviews of the Asian, Australian and African species are missing. Furthermore, the chemical composition has not been thoroughly reviewed since 2007.

PURPOSE

This review summarises and discusses the available data about the chemical composition of propolis from the stingless bee species (Meliponinae) of the Americas, Asia and Australia, published after 2007. The published information on the biological action of chemically characterised Meliponini propolis, and of individual constituents, is addressed. The plant sources of this propolis are also considered.

CONCLUSION AND PERSPECTIVES

Chemical studies of Meliponini propolis has resulted in the discovery of new natural molecules, some of them with valuable bioactivity. Moreover, finding known molecules in propolis stimulates the study of their pharmacological properties. The enormous chemical variability of stingless bee propolis is a challenge to chemists, entomologists and pharmacologists. It is essential to perform pharmacological studies with only chemically characterised propolis of stingless bees. Further studies are required to chemically characterise and scientifically support the medicinal properties of stingless bee propolis and to clarify the potential for its commercial use. This could lead to increased prices for Meliponinae propolis and provide an additional source of income for farmers in rural communities with most serious social needs.

Propolis Extract and Its Bioactive Compounds-From Traditional to Modern Extraction Technologies

Propolis is a honeybee product known for its antioxidant, anti-inflammatory, anticancer, and antimicrobial effects. It is rich in bioactive molecules whose content varies depending on the botanical and geographical origin of propolis. These bioactive molecules have been studied individually and as a part of propolis extracts, as they can be used as representative markers for propolis standardization. Here, we compare the pharmacological effects of representative polyphenols and whole propolis extracts. Based on the literature data, polyphenols and extracts act by suppressing similar targets, from pro-inflammatory TNF/NF-κB to the pro-proliferative MAPK/ERK pathway. In addition, they activate similar antioxidant mechanisms of action, like Nrf2-ARE intracellular antioxidant pathway, and they all have antimicrobial activity. These similarities do not imply that we should attribute the action of propolis solely to the most representative compounds. Moreover, its pharmacological effects will depend on the efficacy of these compounds’ extraction. Thus, we also give an overview of different propolis extraction technologies, from traditional to modern ones, which are environmentally friendlier. These technologies belong to an open research area that needs further effective solutions in terms of well-standardized liquid and solid extracts, which would be reliable in their pharmacological effects, environmentally friendly, and sustainable for production.

Cytotoxicity and Pro-Apoptotic, Antioxidant and Anti-Inflammatory Activities of Geopropolis Produced by the Stingless Bee Melipona fasciculata Smith

Geopropolis is produced by some stingless bee species, such as Melipona fasciculata Smith, a native species from Brazil. This study aims to investigate the antioxidant and anti-inflammatory activities and cytotoxicity effects of geopropolis hydroethanolic extracts against lung (H460 and A549) and ovarian (A2780 and ES2) cancer cell lines and non-tumor (HUVEC) cell lines using chemical identification by LC/MS/MS analysis and in silico assays to determine which compounds are associated with bioactivity. The antioxidant activity of extracts and inhibitory activity against COX enzymes were assessed by in vitro assays; cytotoxicity effect was evaluated by the MTT assay; cell cycle was assessed by flow cytometry and apoptosis by Western blotting. The geopropolis extracts showed great radical scavenging potential, preferential inhibition of COX-2, decreased cancer cell viability, non-cytotoxic effects against the non-tumoral cell line, besides modulating the cell cycle and inducing cancer cell apoptosis through the activation of caspase-3 and PARP protein cleavage. The in silico study suggests that corilagin, typhaneoside, taraxerone and marsformosanone, identified by LC/MS/MS, can be associated with anti-inflammatory activity and cytotoxic effects. Thus, the current study suggests the potential of geopropolis concerning the research field of new pharmacological alternatives regarding cancer therapy.

A comprehensive characterization of polyphenols by LC-ESI-QTOF-MS from Melipona quadrifasciata anthidioides geopropolis and their antibacterial, antioxidant and antiproliferative effects

The geopropolis is a unique type of propolis produced by some stingless bee species. This product is known in folk medicine for its pharmacological properties, mainly antimicrobial and antioxidant, but there are few scientific studies that prove these properties. The objective of this study was to evaluate the phenolic composition and the antimicrobial, antioxidant and antiproliferative activities of Melipona quadrifasciata geopropolis. The phenolic characterization of the geopropolis ethanolic extract was evaluated by LC-ESI-QTOF-MS. The antimicrobial activity was carried out against Gram-positive (including multiresistant microorganisms), negative and yeast. The synergistic effect was evaluated in association with Sulfamethoxazole + Trimethoprim. DPPH, ABTS, FRAP, ORAC and HPLC on-line were used to evaluate the antioxidant activity. Antiproliferative activity was assessed by the sulforhodamine B assay. Flavonoids and phenolic acids were identified in the extract, which showed promising antimicrobial activity, partially synergistic effect and antioxidant activity.