The Study of Chemical Profile and Antioxidant Properties of Poplar-Type Polish Propolis Considering Local Flora Diversity in Relation to Antibacterial and Anticancer Activities in Human Breast Cancer Cells

Abstract

Nine samples of ethanolic extracts of poplar-type propolis (EEP) originated from South-Eastern Poland were analyzed in terms of the diversity of the flora around the apiary. The mineral composition, antioxidant properties, polyphenolic profile (HPTLC), and main polyphenolic constituents (HPLC-DAD) were determined. Only minor differences in chemical composition and antioxidant capacity between tested EEPs were found regardless of their botanical origin. However, the biological activity of the EEPs was more diversified. The tested EEPs showed stronger antibacterial activity against Gram-negative bacteria (Escherichia coli) compared to Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis). Staphylococci biofilm inhibition occurred as a result of exposure to the action of four out of nine EEPs (P1–P4). Due to the various compositions of individual EEPs, a different MCF-7 cellular response was observed according to inhibition of cells migration and proliferation. Almost every sample inhibited the migration of breast cancer cells at a low concentration (0.04 µg/mL) of propolis. Even at the lowest concentration (0.02 µg/mL), each EEP inhibited the proliferation of MCF-7 cells, however, the level of inhibition varied between samples.

Correlation between Chemical Profile of Georgian Propolis Extracts and Their Activity against Helicobacter pylori

“…One of the natural products known as a natural remedy for various infectious diseases, among them H. pylori infection, is propolis [ 19 , 20 , 21 ]. Propolis, known also as “bee glue” is a resinous mixture that different species of honeybees produce from plant exudates gathered from tree buds and flowers, as well as other botanical sources, and bee salivary secretions, wax, and pollen [ 22 ].…”

A novel black poplar propolis extract with promising health-promoting properties: focus on its chemical composition, antioxidant, anti-inflammatory, and anti-genotoxic activities

“…The TPC of BPP extract S1 was found to be among the highest measured so far for alcoholic and hydro-alcoholic extracts from black poplar-type propolis. 64–66 Moreover, the BPP extract S1 exhibited a TPC more than twice higher than that measured in our laboratory in two similar extracts available on the Italian market (BPP extracts S2 and S3).…”

“…As previously anticipated (section 3.1), the TPC of BPP extract S1 was found to be among the highest measured so far for similar extracts. 64–66…”

Do ultrasonic field effects upon the polyphenolics profile of propolis extracts improve their antioxidant and antimicrobial activity?

“…Numerous studies revealed the amazing and complex mechanism of the propolis action to preserve/improve human health through the activity of the polyphenolic derivatives [1] , [2] , [3] , [4] , [5] , [6] . Propolis compounds also inhibit some proteins responsible for cancer cells proliferation (e.g., cyclin B, Claudin-2) or activate others involved in the apoptosis process stopping cell division and enhancing the action of cancer drugs [7] .…”

“…While most investigations report on results obtained using hydroalcoholic mixtures in the 70–99 % range [2] , [3] , [4] , [22] , [23] , [31] , larger proportions of water were also tested [32] , [33] , demonstrating that water-based solvents tend to extract more phenolic acids than flavonoids. Extraction yield peaks around 40–60 % (v/v) ethanol, when a plateau is reached.…”