Isolation of phenolic compounds from eco-friendly white bee propolis: Antioxidant, wound-healing, and anti-Alzheimer effects

This study presents the first findings regarding extraction, isolation, enzyme inhibition, and antioxidant activity. The oral mucosal wound-healing process was investigated using propolis water extract (PWE) incubation with gingival fibroblast cells and concluded that propolis was effective on the oral mucosal wound-healing pattern compared to untreated controls. Additionally, phenolic compounds (fraxetin, apigenin, galangin, pinobanksin, chrysin, etc.) were isolated from propolis, and their chemical structures were elucidated using comprehensive spectroscopic methods. The antioxidant and anti-Alzheimer potential activities of PWE and some isolated compounds were screened and revealing their inhibitory effects on acetylcholinesterase (AChE) with IC50 values ranging from 0.45 ± 0.01 to 1.15 ± 0.03 mM, as well as remarkable free-radical scavenging and metal reduction capacities. The results suggest that these compounds and PWE can be used as therapeutic agents due to their antioxidant properties and inhibitory potential on AChE. It can also be used for therapeutic purposes since its wound-healing effect is promising.

Iranian propolis efficiently inhibits growth of oral streptococci and cancer cell lines

Background

Propolis is a natural bee product with a wide range of biological activities that are related to its chemical composition. The present study investigated the quantification of quercetin (Q) in Ardabil ethanol extract of propolis (AEEP), and then compared its anti-bacterial, anti- biofilm and cytotoxic effects on cancer and normal cell lines.

Method

In the present study, the chemical composition of AEEP was determined through the high-performance liquid chromatography (HPLC). The AEEP and its main component, quercetin (Q), were evaluated in vitro against 57 oral streptococci by a broth micro-dilution method. The biofilm formation was assessed through the crystal violet staining and MTT assays. The impact of AEEP and Q anti-proliferative effect were evaluated on the fibroblast as normal and cancer cell lines (KB and A431).

Results

The Q concentration in the composition of AEEP was 6.9% of all its components. The findings indicated that the AEEP and Q were efficient against the cariogenic bacteria and were able to inhibit the S.mutans biofilm adherence at a sub-MIC concentration. Moreover, electron micrographs indicated the inhibition of biofilms compared to control biofilms. In addition, the AEEP and Q indicated a dose-dependent cytotoxic effect on A431 and KB cell lines. On the contrary, they had no cytotoxic effect on fibroblast cells.

Conclusion

The results indicated that the synergistic impact of main components of AEEP was related to the inhibition of the cancer cell proliferation, cariogenic bacteria and oral biofilm formation. It may play a promising role in the complementary medicine and, it is suggested to be used as food additives.

Propolis attenuates lipopolysaccharide-induced inflammatory responses through intracellular ROS and NO levels along with downregulation of IL-1β and IL-6 expressions in murine RAW 264.7 macrophages

Propolis had a wide spectrum of biological activities. In the current study, antioxidative and the immunomodulatory effects of the Polur ethanol extract of propolis (PEEP) in murine macrophage (RAW 264.7) cells were investigated. Bioactive composition of the PEEP was determined by HPLC analysis. Cells were treated with different concentrations of PEEP and LPS, then cell viability, NO levels, and expression of inflammatory factors were evaluated. HPLC analysis of PEEP indicated the presence of flavonoids and phenolic acid. The PEEP inhibited the proliferation of RAW 264.7 cells with IC₅₀ 15 ± 3.2 µg/ml. Reactive oxygen species (ROS) and NO production was significantly reduced by 0.15 µg/ml of PEEP. Additionally, expression of Cox-2, IL-1β and IL-6 significantly decreased. The obtained results supported the PEEP anti-inflammatory effects on RAW 264.7 cells may be applied via reducing ROS and NO production along with COX-2, IL-1β, and IL-6 expression. PRACTICAL APPLICATIONS: Propolis is a resinous substance produced by the honeybee that has been adopted as a form of traditional medicine since ancient times. The main compounds found in propolis are typically various and depend on the type of plants and climatic region. In this respect, a wide spectrum of biological activities for propolis has been identified including antioxidant, antimicrobial, anticarcinogenic, anti-inflammatory, as well as antifungal properties. This extraordinary substance is rich in flavonoids and antioxidants. Therefore, it is now widely used in foods and drinks with the claim that it can maintain or improve human health.