Phytochemical Screening, Antioxidant and Antibacterial Activities of Pollen Extracts from Micromeria fruticosa, Achillea fragrantissima, and Phoenix dactylifera

Abstract

Pollen is a male flower gametophyte located in the anthers of stamens in angiosperms and a considerable source of compounds with health protective potential. In the present work, phytochemical screening was carried out as well as analysis of the antioxidant and antibacterial properties of pollen extracts from Micromeria fruticosa, Achillea fragrantissima, and Phoenix dactylifera growing wild in Palestine. Phytochemical screening examined the total flavonol, flavone and phenolic content. The DPPH (1,2-Diphenyl-1-Picrylhydrazyl) and FRAP (ferric reducing antioxidant power) methods were used to assess antioxidant propriety, and disc diffusion, minimum inhibitory and bactericidal concentration tests were used to test the pollen extract’s antibacterial activity against multidrug-resistant (MDR) clinical isolates. The highest level of total phenolic was found in the extract of Micromeria fruticosa (56.78 ± 0.49 mg GAE (Gallic Acid Equivalent)/g). The flavone and flavonol content of samples ranged from 2.48 ± 0.05 to 8.03 ± 0.01 mg QE (Quercetin Equivalent)/g. Micromeria fruticosa pollen with IC50 values of 0.047 and 0.039 mg/mL in the DPPH and FRAP assays, respectively, showed the greatest radical scavenging action. In addition, this pollen showed a mild antibacterial action against the microorganisms studied, with MICs varying from 0.625 to 10 mg/mL and inhibition diameters ranging from 13.66 ± 1.5 to 16.33 ± 1.5 mm.

Antimicrobial and Antioxidant Properties of Total Polyphenols of Anchusa italica Retz

“…The determination of (2,2-diphenyl-1-picrylhydrazyl) was performed according to the following protocol [44]. We mixed 200 µL of each series dilution of the two extracts with 750 µL of DPPH (0.004%).…”

“…This test is based on the following method described by Sadiq et al [44], with a slight modification. MH agar plates were prepared from standardized bacterial suspensions (10 8 CFU/mL) and inoculated by swabbing.…”

Polysaccharides, Total Phenolic, and Flavonoid Content from Different Kenaf (Hibiscus cannabinus L.) Genotypes and Their Antioxidants and Antibacterial Properties

“…Plant bioactive constituents have been a major area of interest to scientists in recent years due to their great potential in human health. Phenolic and flavonoid compounds are part of the plant bioactive substances exhibiting antioxidant and antibacterial properties [5][6][7] and are widely distributed in vegetables, fruits, and herbaceous medicinal plants [8]. Similarly, polysaccharides from plants have been proven to possess a good biological activity, such as immunity regulation, antitumor activity [9], antioxidant activity [10], and antibacterial activity [11].…”

Chemical Composition, Antibacterial and Antifungal Activity of the Essential Oil from Cistus ladanifer L.

“…At the same time, A. baumannii demonstrated complete resistance to all tested antibiotics. This may be due to the higher resistance of Gram-negative bacteria due to the complexity of their cell wall, containing a double membrane in opposition to the single glycoprotein/teichoic acid membrane of Gram-positive bacteria [35]. 2 represent the results of the agar disk-diffusion method for C. ladanifer essential oil against the selected bacterial strains after 24 h at 37 • C. The agar disk diffusion method results indicated that the essential oil of C. ladanifer has a remarkable antibacterial activity compared to the concentration used (5 µL).…”