Correlation between total phenolic and flavonoid contents and biological activities of 12 ethanolic extracts of Iranian propolis

The evaluation of L-arginine solution as a solvent for propolis extraction: The phenolic profile, antioxidant, antibacterial activity, and in vitro bioaccessibility

Ethanol has been widely used for the extraction of propolis. Due to its certain disadvantages, there has been an ongoing search to find alternative non-ethanolic extraction solvents. This study aimed to compare the phenolics, antioxidant, and antibacterial activity of propolis extracts prepared with 70% ethanol (EWE), propylene glycol (PGE), and L-arginine solution (BE). All extracts were subjected to an in vitro simulated digestion procedure, and the phenolic profile of non-digested and digested samples was determined by using LC-MS/MS. Additionally, the change in total phenolic (TPC), total flavonoid content (TFC), and antioxidant capacities were determined at each digestion phase. TPC and TFC of non-digested propolis extracts had similar values, although BE showed higher antioxidant capacity (p < .05). The amount of TPC reached or transformed at the intestinal stage was higher for BE and PG compared to EWE. BE also provided the highest antioxidant capacity assay in digested samples. The most common phenolics were pinocembrin, pinobanskin, galangin, and CAPE in non-digested extracts. However, their concentration was drastically reduced by digestion, and their recovery (R%) ranged from 0% to 9.38% of the initial amount detected in the non-digested extracts. Chrysin was the most bioaccessible flavonoid in all extracts. Among phenolic acids, the highest R% was determined for trans-cinnamic acid (22.14%) from BE. All extracts showed in vitro inhibitory activity against Escherichia coli and Staphylococcus aureus. This study suggests that an L-arginine solution could be used as an alternative solvent to ethanol and propylene glycol for propolis extraction.

The exogenous application of naringenin and rosmarinic acid modulates functional traits in Lepidium sativum

BACKGROUND

Phenolic modulators have attracted attention for their potential in shaping functional traits in plants. This work investigated the impact of naringenin (Nar) and rosmarinic acid (RA) on the functional properties of Lepidium sativum leaves and roots.

RESULTS

Untargeted metabolomics identified a diverse phenolic profile, including flavonoids, phenolic acids, low molecular weight phenolics, lignans, and stilbenes. Cluster, analysis of variance multiblock orthogonal partial least squares (AMOPLS), and orthogonal projection to latent structures discriminant analysis (OPLS-DA) multivariate analyses confirmed tissue-specific modulation of bioactive compounds. The tissue was the hierarchically most influential factor, explaining 27% of observed variability, while the treatment and their interaction were statistically insignificant. Thereafter, various in vitro assays were employed to assess antioxidant capacity, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radical scavenging activity, cupric ion reducing antioxidant capacity (CUPRAC), and ferric ion reducing antioxidant power (FRAP), metal chelating ability, and phosphomolybdenum (PMD) assays. Extracts were also tested for inhibitory effects on cholinesterase, amylase, glucosidase, and tyrosinase enzymes. RA application positively impacted antioxidant and enzyme inhibitory activities, holding valuable implications in shaping the health-promoting properties of L. sativum.

CONCLUSION

The untargeted metabolomics analysis showed a significant tissue-dependent modulation of bioactive compounds, determining no synergistic effect between applying phenolic compounds in combination. Specifically, the sole application of RA increased anthocyanins and hydroxyphenyl propanoic acid content on leaves, which was strictly related to enhancing the biological activities. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Biochemical Profile and Antioxidant Properties of Propolis from Northern Spain

The antioxidant, anti-inflammatory, and antimicrobial characteristics of propolis, a bioactive compound collected from hives, have prompted its use in the food sector in recent times. This study investigated the physicochemical characteristics, phenolic profile, and antioxidant capacity of 31 propolis extracts collected from Northern Spain. The physicochemical composition (resins, waxes, ashes mineral content, and heavy metals) was within the allowable regulatory limits. The analysis of bioactive compounds enabled the identification of 51 constituents: flavonoids (apigenin, catechin, chrysin, quercetin, and pinocembrin) and phenolic acids (caffeic, ferulic, and coumaric). The mean value of total polyphenols was 42.72 ± 13.19 Pinocembrin-Galangin Equivalents/100 g, whereas a range between 1.64 ± 0.04 and 4.95 ± 0.36 Quercetin Equivalents (QE) g/100 g was found for total flavonoids content. The determination of bioactivities revealed significant antioxidant capacity using DPPH (1114.28 ± 10.39 µM Trolox Equivalents and 3487.61 ± 318.66 µM Vitamin C Equivalents). Resin content in propolis samples was positively and significantly correlated with both polyphenols (rho = 0.365; p = 0.043) and flavonoid composition (rho = 0.615; p = 0.000) as well as the antioxidant capacity TEAC DPPH (rho = 0.415; p = 0.020). A multiple regression analysis modeled the correlation between resin composition, flavonoids, and TEAC DPPH values, yielding a significant regression equation (R2 = 0.618; F (2,28) = 22.629; p < 0.000; d = 2.299). Therefore, evaluating physicochemical parameters and biological activities provides a promising framework for predicting propolis' quality and antioxidant properties, thus suggesting its potential as a functional and bioactive compound for the food industry.

Synthesis of optimized propolis solid lipid nanoparticles with desirable antimicrobial, antioxidant, and anti-cancer properties

This study aimed to produce stable propolis nanoparticles with a size below 100 nm, suitable for various applications in industries such as pharmaceuticals, medicine, cosmetics, food, and packaging. To achieve this, propolis solid lipid nanoparticles (PSLNs) were synthesized using the hot homogenization method, and the optimized nanoparticles were analyzed using Design Expert software. The properties of the synthesized PSLN were characterized using UV-visible spectroscopy, FTIR, XRD, PSA, TEM, and zeta potential analysis. The results indicated that PSLNs with a size range of 57 ± 15 nm remained stable in an aqueous medium at pH 7.4. HPLC analysis showed that the active ingredient of phenols and flavonoids in the extract remained stable after the formation of PSLNs. Antioxidant and antibacterial properties of the extract and nanoparticles were also evaluated. The results demonstrated that the biological properties of the extract were effectively preserved in PSLNs, Additionally, the PSLN synthesized exhibited remarkable anticancer properties against the A549 cell line and with IC50 of 0.01 mg/ml after 72 h-treatment. In conclusion, the optimized PSLNs can be utilized as antioxidant and antibacterial additives and have the potential to be used as a drug or drug carrier for the treatment of lung cancer.

Comparison of the Chemical Composition and Antioxidant Properties of Propolis from Urban Apiaries

Bee products from urban apiaries are increasingly used. They are mainly used to promote local apiaries and cities in which they are located. The aim of the study was to compare the chemical composition and antioxidant activity of propolis from 6 Polish apiaries located in cities (Legionowo, Torun, Cracow, Warsaw, Katowice, Lodz). The chemical composition was analyzed using liquid chromatography (HPLC-DAD) and the analysis of antioxidant activity by scavenging free radicals (ABTS and DPPH) and FRAP. The obtained results showed the presence of 24 phenolic compounds in propolis extracts. The tested samples showed differentiation in terms of the content of individual chemical components, however, cinnamic acid and its derivatives were dominant. High antioxidant activity of the tested extracts was demonstrated (ABTS was in the range of 16.80-51.53 mg Te/mL, DPPH was in the range of 7.54-22.13 mg Te/mL, while FRAP reduction was in the range of 10.93-29.55 mg Te/mL). The obtained results compared with literature data on propolis from agricultural areas allow to conclude that propolis samples from both Poland types of areas are similar and can be classified as poplar propolis.

Chia Phenolic Extract Appear to Improve Small Intestinal Functionality, Morphology, Bacterial Populations, and Inflammation Biomarkers In Vivo (Gallus gallus)

Phenolic compounds can act as a substrate for colonic resident microbiota. Once the metabolites are absorbed and distributed throughout the body, they can have diverse effects on the gut. The objective of this study was to evaluate the effects of the intra-amniotic administration of a chia phenolic extract on intestinal inflammation, intestinal barrier, brush border membrane functionality, intestinal microbiota, and morphology in vivo (Gallus gallus model). Cornish-cross fertile broiler eggs, at 17 days of embryonic incubation, were separated into groups as follows: non-injected (NI; this group did not receive an injection); 18 MΩ H2O (H2O; injected with ultrapure water), and 10 mg/mL (1%) chia phenolic extract (CPE; injected with phenolic extract diluted in ultrapure water). Immediately after hatch (21 days), chickens were euthanized and their small intestine, cecum, and cecum content were collected and analyzed. The chia phenolic extract reduced the tumor necrosis factor-alpha (TNF-α) and increased the sucrose isomaltase (SI) gene expression, reduced the Bifidobacterium and E. coli populations, reduced the Paneth cell diameter, increased depth crypt, and maintained villus height compared to the non-injected control group. Chia phenolic extract may be a promising beneficial compound for improving intestinal health, demonstrating positive changes in intestinal inflammation, functionality, microbiota, and morphology.