Potential Application of Luteolin as an Active Antibacterial Composition in the Development of Hand Sanitizer Products

Biological potential, chemical profiling, and molecular docking study of Morus alba L. extracts

Morus alba L. is a plant with a long history of dietary and medicinal uses. We hypothesized that M. alba possesses a significant biological potential. In that sense, we aimed to generate the chemical, antimicrobial, toxicological, and molecular profile of M. alba leaf and fruit extracts. Our results showed that extracts were rich in vitamin C, phenols, and flavonoids, with quercetin and pterostilbene concentrated in the leaf, while fisetin, hesperidin, resveratrol, and luteolin were detected in fruit. Extracts exhibited antimicrobial activity against all tested bacteria, including multidrug-resistant strains. The widest inhibition zones were in Staphylococcus aureus ATCC 33591. The values of the minimum inhibitory concentration ranged from 15.62 μg/ml in Enterococcus faecalis to 500 μg/ml in several bacteria. Minimum bactericidal concentration ranged from 31.25 μg/ml to 1000 μg/ml. Extracts impacted the biofilm formation in a concentration-dependent and species-specific manner. A significant difference in the frequency of nucleoplasmic bridges between the methanolic extract of fruit (0.5 μg/ml, 1 μg/ml, 2 μg/ml), as well as for the frequency of micronuclei between ethanolic extract of leaf (2 μg/ml) and the control group was observed. Molecular docking suggested that hesperidin possesses the highest binding affinity for multidrug efflux transporter AcrB and acyl-PBP2a from MRSA, as well as for the SARS-CoV-2 Mpro. This study, by complementing previous research in this field, gives new insights that could be of great value in obtaining a more comprehensive picture of the Morus alba L. bioactive potential, chemical composition, antimicrobial and toxicological features, as well as molecular profile.

Antibacterial and Antioxidant Activity of Synthetic Polyoxygenated Flavonoids

Flavonoids are an abundant class of naturally occurring compounds with broad biological activities, but their limited abundance in nature restricts their use in medicines and food additives. Here we present the synthesis and determination of the antibacterial and antioxidant activities of twenty-two structurally related flavonoids (five of which are new) by scientifically validated methods. Flavanones (FV1-FV11) had low inhibitory activity against the bacterial growth of MRSA 97-7. However, FV2 (C5,7,3',4' = OH) and FV6 (C5,7 = OH; C4' = SCH3) had excellent bacterial growth inhibitory activity against Gram-negative E. coli (MIC = 25 µg/mL for both), while Chloramphenicol (MIC = 25 µg/mL) and FV1 (C5,7,3' = OCH3; 4' = OH) showed inhibitory activity against Gram-positive L. monocytogenes (MIC = 25 µg/mL). From the flavone series (FO1-FO11), FO2 (C5,7,3',4' = OH), FO3 (C5,7,4' = OH; 3' = OCH3), and FO5 (C5,7,4' = OH) showed good inhibitory activity against Gram-positive MRSA 97-7 (MIC = 50, 12, and 50 µg/mL, respectively), with FO3 being more active than the positive control Vancomycin (MIC = 25 µg/mL). FO10 (C5,7= OH; 4' = OCH3) showed high inhibitory activity against E. coli and L. monocytogenes (MIC = 25 and 15 µg/mL, respectively). These data add significantly to our knowledge of the structural requirements to combat these human pathogens. The positions and number of hydroxyl groups were key to the antibacterial and antioxidant activities.

Determination of Luteolin and Apigenin in Herbal Teas by Online In-Tube Solid-Phase Microextraction Coupled with LC-MS/MS

Herbal teas have attracted attention as functional beverages containing luteolin and apigenin, which exhibit antioxidant and anti-inflammatory effects. The objective of this study was to develop a sensitive online automated method to determine these flavones' contents in herbal teas using in-tube solid-phase microextraction (IT-SPME) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). These compounds were extracted and concentrated by IT-SPME using a Supel Q PLOT capillary column and then separated and detected within 6 min using a CAPCELL PAK C18 MG III analytical column and a negative electrospray ionization-mode multiple-reaction monitoring system by LC-MS/MS. The detection limits (S/N = 3) for luteolin and apigenin were 0.4 and 0.8 pg mL-1, respectively, and the calibration curves were linear in the range of 2-2000 pg mL-1 with correlation coefficients above 0.9995, and intra-day and inter-day precisions with relative standard deviations below 2.9 and 3.6% (n = 6), respectively. The luteolin and apigenin in herbal tea were quantified using IT-SPME/LC-MS/MS following the acid hydrolysis of their glycosides. Among the 10 herbal teas tested, luteolin was detected in peppermint and sage at concentrations of 375 and 99 µg mL-1, respectively, while apigenin was detected in German chamomile at 110 µg mL-1, which were higher than in the other herbal teas. The method is expected to be a useful method for evaluating the efficacy of luteolin and apigenin in herbal teas as functional beverages.

Identification of Phytochemicals with Inhibitory Potential Against Beta-lactamase Enzymes via Computer-aided Approach

INTRODUCTION

Antibacterial drugs have been widely used for the past century to treat diseases, but their efficacy has been limited by multi-resistant pathogens, particularly those that utilize beta-lactamase enzymes. The inhibition of beta-lactamase enzymes holds great promise for reducing the influence of such pathogens.

OBJECTIVE

This study aims to evaluate the mechanism of inhibition of phytochemicals with antibacterial activity against two classes of beta-lactamases using computational methods.

METHODS

To achieve this objective, a total of thirty phytochemicals were docked against SHV-1 beta-lactamase and AmpC beta-lactamase after procurement from Protein Data Bank. The pharmacokinetics (ADMET) and density functional theory (DFT) analysis study were also conducted to unravel the nature of the top six most promising compounds on each protein.

RESULTS

The results showed that a significant percentage of the compounds had binding affinities greater than that of avibactam, the positive control. Quercetin-3-O-rutinoside showed the most promising results against SHV-1 beta-lactamase with an affinity of -9.4 kcal/mol, while luteolin was found to be the most promising candidate against AmpC beta-lactamase with an affinity of -8.5 kcal/mol. DFT analysis demonstrated the reactivity of these compounds, and the ADMET study indicated that they were relatively safe.

CONCLUSION

In conclusion, the study's findings suggest that the selected compounds have significant potential to inhibit beta-lactamase and may be used in combination with antibiotics against organisms that produce beta-lactamase. This study provides a basis for further research in a wet-lab setting to validate the results.

Flavonoids and phenolic acids from sugarcane: Distribution in the plant, changes during processing, and potential benefits to industry and health

Sugarcane (Saccharum sp.) plants are grown in warmer climates throughout the world and processed to produce sugar as well as other useful byproducts such as molasses and bagasse. Sugarcane is rich in (poly)phenols, but there has been no attempt to critically evaluate the published information based on the use of suitable methodologies. The objective of this review is to evaluate the quantitative and qualitative (poly)phenolic profiles of individual parts of the sugarcane plant and its multiple industrial products, which will help develop new processes and uses for sugarcane (poly)phenols. The quantitative analysis involves the examination of extraction, concentration, and analytical techniques used in each study for each plant part and product. The qualitative analysis indicates the identification of various (poly)phenols throughout the sugarcane processing chain, using only compounds elucidated through robust analytical methodologies such as mass spectrometry or nuclear magnetic resonance. In conclusion, sugarcane (poly)phenols are predominantly flavonoids and phenolic acids. The main flavonoids, derivatives of apigenin, luteolin, and tricin, with a substantial proportion of C-glycosides, are consistently found across all phases of sugarcane processing. The principal phenolic acids reported throughout the process include chlorogenic acids, as well as ferulic and caffeic acids mostly observed after hydrolysis. The derivation of precise quantitative information across publications is impeded by inconsistencies in analytical methodologies. The presence of multiple (poly)phenols with potential benefits for industrial applications and for health suggests sugarcane could be a useful provider of valuable compounds for future use in research and industrial processes.

Bioactive compounds from Actinidia arguta fruit as a new strategy to fight glioblastoma

In recent years, there has been a significant demand for natural products as a mean of disease prevention or as an alternative to conventional medications. The driving force for this change is the growing recognition of the abundant presence of valuable bioactive compounds in natural products. On recent years Actinia arguta fruit, also known as kiwiberry, has attracted a lot of attention from scientific community due to its richness in bioactive compounds, including phenolic compounds, organic acids, vitamins, carotenoids and fiber. These bioactive compounds contribute to the fruit's diverse outstanding biological activities such as antioxidant, anti-inflammatory, neuroprotective, immunomodulatory, and anti-cancer properties. Due to these properties, the fruit may have the potential to be used in the treatment/prevention of various types of cancer, including glioblastoma. Glioblastoma is the most aggressive form of brain cancer, displaying 90 % of recurrence rate within a span of 2 years. Despite the employment of an aggressive approach, the prognosis remains unfavorable, emphasizing the urgent requirement for the development of new effective treatments. The preclinical evidence suggests that kiwiberry has potential impact on glioblastoma by reducing the cancer self-renewal, modulating the signaling pathways involved in the regulation of the cell phenotype and metabolism, and influencing the consolidation of the tumor microenvironment. Even though, challenges such as the imprecise composition and concentration of bioactive compounds, and its low bioavailability after oral administration may be drawbacks to the development of kiwiberry-based treatments, being urgent to ensure the safety and efficacy of kiwiberry for the prevention and treatment of glioblastoma. This review aims to highlight the potential impact of A. arguta bioactive compounds on glioblastoma, providing novel insights into their applicability as complementary or alternative therapies.

Avian safety guardian: Luteolin restores Mycoplasma gallisepticum-induced immunocompromise to improve production performance via inhibiting the IL-17/NF-kB pathway

Mycoplasma gallisepticum (MG) is a major pathogen causing chronic respiratory disease (CRD) in chickens. Exposure to MG poses a constant threat to chicken health and causes substantial economic losses. Antibiotics are the main treatment for MG infections, but have to struggle with antibiotic residues and MG resistance. To date, no safe and more effective prevention or treatment for MG infections has been identified. Luteolin (Lut) is a natural flavonoid compound known for its excellent anti-viral, anti-bacterial, immunoregulatory, and anti-inflammatory pharmacological activities. Herein, we established an MG-infected model using partridge shank chickens and chicken-like macrophages (HD11 cells) to investigate the effect and potential mechanism of Lut against MG-induced immune damage. According to our findings, Lut significantly inhibited the expression of MG adhesion protein (pMGA1.2) in vivo and in vitro. Lut effectively mitigated the MG-induced decrease in body weight gain, feed conversion ratio, survival rate, and serum IgG and IgA levels. Lut directly repaired MG-induced spleen and thymus damage by histopathological analysis. Furthermore, network pharmacology analysis revealed that Lut most probably resisted MG infection through the IL-17/NF-kB pathway. In vivo and in vitro experiments, Lut significantly suppressed the increase in key protein IL-17A, TRAF6, p-p65, and p-IkBα in the IL-17/NF-kB pathway. Meanwhile, Lut markedly alleviated MG-induced the increase of pro-inflammatory cytokines TNF-α, IL-6, IL-1β, pro-apoptotic genes caspase3 and caspase9, while promoting the expression of anti-apoptotic genes Bcl-2 and Bcl-XL. In summary, Lut effectively suppressed MG colonization, alleviated MG-induced the production performance degradation, inflammatory responses, and immune damage by inhibiting the IL-17/ NF-kB pathway. This study indicates Lut can serve as a safe and effective antibiotic alternative drug for preventing and treating MG-induced CRD. It also provides new evidence to explore the molecular mechanisms of MG infection.

Hand Sanitizer Gels: Classification, Challenges, and the Future of Multipurpose Hand Hygiene Products

Hand hygiene is a crucial measure in the prevention and control of infections, and there is a growing awareness among individuals who are making a conscious effort to maintain hand cleanliness. With the advent of the SARS-CoV-2 outbreak, the demand for hand hygiene products has also gradually shifted towards those with antimicrobial properties. Among these products, hand sanitizer gels (HSGs) have gained considerable popularity as an efficient method of hand cleaning, due to their rapid drying and sustained antimicrobial efficacy. Concurrently, there has been a growing interest in novel HSGs that offer additional functions such as skin whitening, moisturizing, and anti-inflammatory effects. These novel HSGs effectively address concerns associated with the ingestion of antimicrobial ingredients and demonstrate reduced skin irritation, thereby alleviating hand dermatological issues. This review provides an extensive overview of the application scenarios, classification, and challenges associated with HSGs while emphasizing the emergence of novel components with biological functions, aiming to contribute to the advancement of hand hygiene practices and offer novel insights for the development of novel HSGs with outstanding antimicrobial properties with other multiple biological functions and desirable biosafety profiles.