In this study the effect of pollen source (mesquite and catclaw) on the sensory characteristics (appearance, color, aroma, taste, consistency and visible impurities), and physicochemical properties of raw propolis, and the phenolic content and biological activities of propolis extracts (PEs) was determined. The phenolic composition of PEs was determined by the total phenolic (TPC), flavone and flavonol (FFC), and flavanone and dihydroflavonol content (FDC). The individual phenolic components were analyzed by HPLC-DAD. The antioxidant activity was determined by the ferric-reducing power (FRAP) and free-radical scavenging activity (FRS). The antibacterial activity was evaluated against Gram-positive (Staphylococcus aureus and Listeria innocua) and Gram-negative (Echerichia coli and Salmonella thyphimurium) bacteria. The results showed that sensory characteristic and physicochemical properties of mesquite and catclaw propolis complied with international quality regulations. Fifteen phenolic compounds were identified, of which pinocembrin, naringenin, galangin, chrysin and quercetin were found a high concentration (> 3 mg/g). Mesquite propolis had the highest phenolic content (TFC and FDC), as well as antioxidant activity (> 2.5 mg Fe (II) equivalent/g; > 40% of DPPH radical inhibition) and antibacterial activity against Gram-positive bacterias in the order S. aureus > L. innocua (> 50% of inhibition for both bacterias at 500 µg/mL). These results indicating that pollen source affect the sensory characteristics and physicochemical properties of propolis, as well as the biological activity of their extracts.

The present manuscript reviews the findings of different research studies that evaluate the use of fungal solid-state (SSF) and submerged culture fermentation (SCF) with agro-industrial residues as substrates to enhance the production of polyphenols and their possible uses as food additives. Some agro-industrial residues (peels, pulps and seeds) are an important source of phenolic acids (p-coumaric, p-hydroxybenzoic, chlorogenic, cinnamic, ferulic, gallic, gentisic, protocatechuic, rosmarinic, salycilic, syringic, and vanillic acids) and flavonoid compounds (apigenin, chrysin, (+)-catechin, kaempferol, myricetin, quercetin, rutin, hesperetin, and naringin). In addition, the utilization of these residues as substrates in SCF and SSF enhances polyphenol production, improves biological function by increasing antioxidant and antimicrobial activities, and provides a potential alternative to synthetic antioxidant uses in the meat and meat products industry.

This study describes the thermal effect on physicochemical properties, phenolic content, as well as antioxidant and antibacterial activity of edible mushroom extracts (EME) from Agaricus brasiliensis, Ganoderma lucidum, and Pleurotus ostreatus in aqueous-ethanolic solution. The heating of EME resulted in a reduction of pH and total soluble solids and changes in color values in time dependence (p < 0.05). In addition, total phenolic and flavonoid contents, antiradical activity (DPPH• and ABTS•+ inhibition), and reducing power were enhanced with increasing temperature (90 °C, for 6 h), mainly in the P. ostreatus extract (p < 0.05). In contrast, the results indicate that high temperatures reduced (p < 0.05) the antibacterial effect against all pathogens tested. In conclusion, the thermal treatment affected physicochemical and antibacterial properties of EME and enhanced phenolic composition and antioxidant activity.