Antioxidant, antibacterial, and antimutagenic activity of Piper nigrum seeds extracts

Effects of Piper betle Extracts against Biofilm Formation by Methicillin-Resistant Staphylococcus pseudintermedius Isolated from Dogs

Emergence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) isolated from dogs with cutaneous and wound infections has significantly impacted veterinary medicine. This study aimed to isolate S. pseudintermedius from canine pyoderma and investigate the effects of ethanolic extracts of Piper betle (PB), P. sarmentosum (PS), and P. nigrum (PN) on the bacterial growth and biofilm formation of S. pseudintermedius and MRSP. Of the isolated 152 isolates, 53 were identified as S. pseudintermedius using polymerase chain reaction, and 10 isolates (6.58%) were identified as MRSP based on the presence of mecA. Based on phenotype, 90% of MRSPs were multidrug-resistant. All MRSP had moderate (10%, 1/10) and strong (90%, 9/10) biofilm production ability. PB extracts were the most effective in inhibiting planktonic cells, and the minimum inhibitory concentration at which ≥50% of the isolates were inhibited (MIC₅₀) was 256 µg/mL (256-1024 µg/mL) for S. pseudintermedius isolates and 512 µg/mL (256-1024 µg/mL) for MRSP isolates. The MIC₉₀ for S. pseudintermedius and MRSP was 512 µg/mL. In XTT assay, PB at 4× MIC showed an inhibition rate of 39.66-68.90% and 45.58-59.13% for S. pseudintermedius and MRSP, respectively, in inhibiting biofilm formation. For PB at 8× MIC, the inhibition rates for S. pseudintermedius and MRSP were 50.74-81.66% and 59.57-78.33%, respectively. Further, 18 compounds were identified in PB using gas chromatography-mass spectrometry, and hydroxychavicol (36.02%) was the major constituent. These results indicated that PB could inhibit bacteria growth of and biofilm formation by S. pseudintermedius and MRSP isolated from canine pyoderma in a concentration-dependent manner. Therefore, PB is a potential candidate for the treatment of MRSP infection and biofilm formation in veterinary medicine.

Evaluation of Antimicrobial Activity and Cytotoxicity Effects of Extracts of Piper nigrum L. and Piperine

P. nigrum L. extracts and the piperine alkaloid have important antimicrobial, anti-inflammatory, and antioxidant properties. Therefore, in this study, we evaluated the antimicrobial activity and cytotoxicity of P. nigrum L. extracts and piperine, a compound isolated from the extracts of P. nigrum L. Extracts obtained via maceration, soxhlet, and purification steps, in addition to isolated piperine, were used in this study. Spectroscopic methods, such as nuclear magnetic resonance, scanning electron microscopy, X-ray diffraction, thermogravimetry, and differential scanning calorimetry, were used to characterize piperine. In the microbiological analyses, the extract obtained via maceration-derived sample showed high efficiency in inhibiting Salmonella spp. (MIC < 100 μg/mL). The extract obtained via a soxhlet-derived sample showed promising inhibitory activity against almost all microorganisms, with negligible inhibition of Pseudomonas aeruginosa. Favorable inhibition coefficients were also observed against Staphylococcus aureus and Salmonella spp. (MIC < 100 μg/mL) for the extract obtained via purification of the steps-derived sample. Piperine showed an excellent inhibition coefficient against most microorganisms, with inactivity only observed against P. aeruginosa. Cytotoxicity evaluation assays in cancer cell lines revealed that piperine exhibited inhibitory potential on all tested tumor cell lines, causing a decrease in cell viability and achieving an IC50 of less than 30 μg/mL. The analyzed extracts from P. nigrum L. seeds showed cytotoxic activity against tumor and non-tumor cell lines.

A perspective review on medicinal plant resources for their antimutagenic potentials

Mutagens present in the environment manifest toxic effects and are considered as serious threat for human health and healthcare. Recent reports reveal that medicinal plant resources are being explored for identifying potent antimutagenic as well as cancer preventing agents. There is mounting evidence that cancer and other mutation-related diseases can be prevented with the use of medicinal pant resources including crude extracts, active fractions, phytochemicals, and pure phytomolecules. These medicinal plant resources possessing antimutagenic potentials have been shown to target molecular mechanisms underlying the mutagenic impacts. Technological advents and high-throughput screening/activity methods have revolutionized this field, though several potent plants and their active principles have been reported as effective antimutagens. The translational success rate needs to be improved, but the trends are encouraging. In this review, we present the current understandings and updates on various mutagens in the environment, toxicities related/attributed to them, the resultant mutations (and cancer), and how medicinal plants come to the rescue. A perspective review has been presented on whether and how medicinal plant resources can be an effective approach for addressing mutagens in the environment. An account of medicinal plant resources used as antimutagenic agents has been given along with the underlying mechanism of action and their therapeutic potential in various models of cancer. Recent success stories, current challenges, and future prospects are discussed.

Evaluation of Anti-Candida Potential of Piper nigrum Extract in Inhibiting Growth, Yeast-Hyphal Transition, Virulent Enzymes, and Biofilm Formation

Due to the increased incidence of fungal infections and the emergence of antifungal resistance mainly by Candida species, the need for safe and effective novel therapies is imperative. Consequently, plants and herbs are a powerful source to combat infections. Here, we evaluated the anti-Candida potential of an ethanolic extract from Piper nigrum. The phytochemical analysis of P. nigrum revealed bioactive compounds such as alkaloids, terpenoids, and tannis. Our results showed that P. nigrum extract suppressed the virulence factors of C. albicans strains, including hyphae formation in both liquid and solid media, reduced secretion of phospholipases/proteinases, and affected biofilm formation. Furthermore, the P. nigrum extract showed no hemolytic effect in vitro and exhibited reduced cytotoxicity on Vero cells and G. mellonella larvae at concentrations that inhibited hyphae and biofilm in C. albicans. Moreover, the extract demonstrated antifungal activity against C. auris strains. In conclusion, the P. nigrum extract affected the growth and morphogenesis of Candida (even in resistant strains), demonstrating that this plant has an anti-candida activity and represents a promising resource for discovering novel antifungal compounds.

Isolation, characterization and in vitro antioxidant activity screening of pure compound from black pepper (Piper nigrum)

The present study's aims of isolation, characterization and in vitro antioxidant activity screening of pure compound from Black pepper (Piper nigrum) were investigated. Nowadays, scientific exploration of medicinal plants from natural sources has become the prime concern globally. All the crude drugs that have been isolated from natural plant origin (herbs, root, stem, bark, fruit and flower) have great significance in drug discovery as well as a lead compound to demonstrate great synergistic effect on pharmacology. For this research work, methanol was selected as a mother solvent, and the crude methanolic extract of black pepper was partitioned in between the solvent chloroform and di-ethyl-ether. A crystal fraction has been eradicated from the chloroform extract of black pepper (Piper nigrum). The crystal compound (C1) was isolated and purified by using thin layer chromatography (TLC) and recrystallization technique. The purified crystal compound (C1) isolated from black pepper possesses a strong in vitro antioxidant activity. The IC50 value of crystal compound (C1) was 4.1 µg/ml where the standard one had 3.2 µg/ml. Physical, phytochemical and chromatographical characterization of pure crystal compound (C1) has been explored, and from the analysis of all characteristics, it was found that, crystal compound (C1) might have resembling features of the standard Piperine of black pepper. The overall research work was really remarkable and introduced a convenient way of isolating pure compound from the natural source which will be a great referential resource in isolating crude drugs for future analysis.

Antimicrobial and anti-biofilm activities of polyphenols extracted from different Saudi Arabian date cultivars against human pathogens

BACKGROUND

Microbial diseases have emerged as a serious threat to the healthcare system globally and also in Saudi Arabia; various diseases are associated with higher mortality and increased spreading rates. Dietary sources are often entertained to improve the immune system of the body to fight against these infections. The date fruit (Phoenix dactylifera L) is one such functional food that is less explored for its actual potentials.

METHODS

The polyphenols isolated from the different cultivars of dates in Saudi Arabia (Ajwa, Safawi, Khalas, and Sukkary) was evaluated for their antibacterial, anti-fungal and anti-biofilm forming abilities. The anti-radical properties of the phenolic extract were conducted in terms of the scavenging of diphenyl-1-picrylhydrazyl radical, hydrogen peroxide radicals and ABTS radicals. The anti-inflammatory potential was analyzed in terms of lipoxygenase activity inhibition.

RESULTS

The phenolic compounds of different dates were spectrophotometrically estimated and cultivars such as Ajwa and Sukkary had the highest polyphenol content. It was also noteworthy that they exerted potent antibacterial activities against Staphylococcus aureus, Streptococcus pyogenes, and Pseudomonas aeruginosa as estimated by the least minimal inhibitory concentration (MIC) or minimal bactericidal concentration (MBC) values. Besides, these polyphenols reduced the biofilm formation by these bacterial pathogens; it is thus possible that the polyphenols from dates can be a promising antimicrobial agent against various pathogenic strains. Corroborating with these, the polyphenol extracts from different Saudi Arabian dates were found to inhibit the growth of mycelium in strains of Candida albicans and Aspergillus niger. Apart from these, the polyphenol isolates also exhibited significant anti-radical properties against different reactive radical systems.

CONCLUSION

Overall, the efficacy of phenolic compounds extracted from the dried date fruits are not only restricted to the functional food features; instead, these molecules are capable of preventing the growth of microbial pathogens of humans. Hence, it may emerge as potent antibacterial, anti-fungal and anti-biofilm forming candidates.