Comparative fingerprint and extraction yield of Diospyrus ferrea (willd.) Bakh. root with phenol compounds (gallic acid), as determined by uv–vis and ft–ir spectroscopy

SPE of gallic acid and ascorbic acid in fruits using polymerized deep eutectic solvent-modified substrate

Aim: Novel substrates were synthesized by porous and nonporous polymerization of deep eutectic solvents on magnetic silica nanoparticles and introduced for dispersive solid-phase extraction of two analytes. Materials & methods: The prepared substrates were characterized, and an extraction procedure was implemented to select the best substrates and eluent. The central composite design acted to optimize the effects of parameters that influenced the extraction efficiencies. Results: For gallic and ascorbic acids, the limits of detection were obtained at 0.136 and 0.165 μM, respectively, with linear ranges of 0.6-125.2 and 0.5-106.8 μM, respectively. Conclusion: The substrate produced good extractions even after being used three-times and was successfully applied for the analysis of real samples.

The Genus Diospyros: A Review of Novel Insights into the Biological Activity and Species of Mozambican Flora

Species of the Diospyros L. genus (Ebenaceae family) have been largely used in traditional medicine for the treatment of several diseases, especially infectious ones. To date, active major compounds such as naphthoquinones, triterpenoids, and tannins have been isolated and pharmacologically validated from Diospyros species. The present study summarizes the information available in the literature on the species described in the Flora of Mozambique. To do so, scientific databases (e.g., PubMed, Scopus, Web of Science, and Google Scholar) were searched using various keywords and Boolean connectors to gather and summarize the information. Of the 31 native and naturalized species in the Flora of Mozambique, 17 are used in different regions of Africa and were described for their traditional uses. They were reported to treat more than 20 diseases, mostly infectious, in the gastrointestinal and oral cavity compartments. This work provides an overview of the therapeutical potential of Diospyros species and explores novel insights on the antimicrobial potential of extracts and/or isolated compounds of these Mozambican species.

Hierarchical tungsten-doped bimetallic selenides nanosheets arrays/nickel foam composite electrode as efficient gallic acid electrochemical sensor

The development of effective and accurate gallic acid (GA) electrochemical sensors is critical for food and pharmaceutical industry and health perspectives. Multi-step hydrothermal treatments of bimetallic (Ni/Co) flaky bimetallic hydroxides (NiCo FBHs) were employed to prepare tungsten-doped cobalt-nickel selenides nanosheets arrays (W-Co_0.5Ni_0.5Se₂ NSAs) serving  as the main active substance of GA detection. The morphology and composition of the W-Co_0.5Ni_0.5Se₂ NSAs/NF were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The GA electrochemical sensor constructed by the W-Co_0.5Ni_0.5Se₂ NSAs/NF composite electrode exhibits two linear concentration ranges of 1.00-36.2 μM and 36.2-1.00×10³ μM for GA electrochemical detection with a limit of detection of  0.120 μM (S/N=3) at the working potential of 0.05 V (vs. SCE). The W-Co_0.5Ni_0.5Se₂ NSAs/NF shows high selectivity, good long-term stability, high recovery in the range 97.9-105%, and a relative standard deviation (RSD) between 0.60 and 2.7%.

Microfluidics as a Ray of Hope for Microplastic Pollution

Microplastic (MP) pollution is rising at an alarming rate, imposing overwhelming problems for the ecosystem. The impact of MPs on life and environmental cycles has already reached a point of no return; yet global awareness of this issue and regulations regarding MP exposure could change this situation in favor of human health. Detection and separation methods for different MPs need to be deployed to achieve the goal of reversing the effect of MPs. Microfluidics is a well-established technology that enables to manipulate samples in microliter volumes in an unprecedented manner. Owing to its low cost, ease of operation, and high efficiency, microfluidics holds immense potential to tackle unmet challenges in MP. In this review, conventional MP detection and separation technologies are comprehensively reviewed, along with state-of-the-art examples of microfluidic platforms. In addition, we herein denote an insight into future directions for microfluidics and how this technology would provide a more efficient solution to potentially eradicate MP pollution.

Stability, Toxicity, and Antibacterial Potential of Gallic Acid-Loaded Graphene Oxide (GAGO) Against Methicillin-Resistant Staphylococcus aureus (MRSA) Strains

Background

The impetuous usage of antibiotics has led to the perpetual rise of methicillin-resistant Staphylococcus aureus (MRSA), which has garnered the interest of potential drug alternatives, including nanomaterials.

Purpose

The present study investigates the stability, toxicity, and antibacterial potential of gallic acid-loaded graphene oxide (GAGO) on several MRSA strains.

Methods

The stability of a synthesized and characterized GAGO was monitored in different physiological media. The toxicity profile of GAGO was evaluated in 3T3 murine fibroblast cells and the embryonic zebrafish model. The antibacterial activity of GAGO against MRSA, methicillin-susceptible S. aureus (MSSA), and community-acquired MRSA; with or without Panton-valentine leucocidin gene (MRSA-pvl+ and MRSA-pvl-) was investigated through disk diffusion, CFU counting method, time-kill experiment, and high-resolution transmission electron microscopy (HRTEM) observation.

Results

A stable GAGO nanocomposite has shown an improved toxicity profile in 3T3 murine fibroblast cells and zebrafish embryos, besides exhibiting normal ROS levels than graphene oxide (GO) and GA (gallic acid). The nanocomposite inhibited the growth of all bacterial strains employed. The effectiveness of the GAGO nanocomposite was comparable to cefoxitin (CFX), at ≥150 µg/mL in MRSA and MSSA. GAGO exhibited a significantly delayed response towards MRSA-pvl+ and MRSA-pvl-, with increased inhibition following 8 to 24 h of exposure, while comparable activity to native GA was only achieved at 24 h. Meanwhile, for MRSA and MSSA, GAGO had a comparable activity with native GA and GO as early as 2 h of exposure. HRTEM observation further reveals that GAGO-exposed cells were membrane compromised.

Conclusion

In summary, the present study indicates the antibacterial potential of GAGO against MRSA strains, but further study is warranted to understand the mechanism of action of GAGO and its resistance in MRSA strains.

Parameter Effects and Optimisation in Supercritical Fluid Extraction of Phenolic Compounds from Labisia pumila

Labisia pumila, locally referred to as kacip fatimah, is one of the important herbs utilised in traditional medicine. Nonetheless, to the best of the researchers’ knowledge, the optimum application of Supercritical Fluid Extraction (SFE) has not been reported for Labisia pumila (L. pumila) extraction and the understanding of this study may offer preliminary insight into the preparation of standardised extracts of L. pumila enriched with natural antioxidants prior to commercialisation at the industrial level. Response surface methodology (RSM) was used to optimise supercritical carbon dioxide extraction (SC-CO2) of functional phenolic compounds from L. pumila leaves. The factors studied were pressure, temperature, percentage of ethanol in co-solvent, and co-solvent concentration. The results demonstrated that the percentage of ethanol in co-solvent, temperature, and co-solvent concentration in the supercritical mixture had significant effects on the extraction of L. pumila. Based on the RSM results, the optimal SC-CO2 extraction conditions were at 283 bar, 32 °C, 78% (v/v) of ethanol-water in co-solvent, and 16% (v/v) of co-solvent concentration, which allowed the recovery of 14.051 ± 0.76% (g/g) of extraction yield, 1.2650 ± 0.10% (g/g) of gallic acid, 0.441 ± 0.29% (g/g) of methyl gallate, and 1.382 ± 0.37% (g/g) of caffeic acid. The experimental values were in agreement with the one predicted by RSM models, confirming the suitability of the model for optimisation of the extraction conditions.

Phytochemical Characterization, Antioxidant, Anti-inflammatory, Anti-diabetic properties, Molecular Docking, Pharmacokinetic Profiling, and Network Pharmacology Analysis of the Major Phytoconstituents of Raw and Differently Dried Mangifera indica (Himsagar cultivar): an In Vitro and In Silico Investigations

Mango (Himsagar cultivar) is a high moisture-bearing seasonal fruit and cultivated in a wide range of the world. Mango pulp is generally preserved by sun drying. In recent days, industries are using hot-air oven, freeze, and microwave drying for mango leather (dried mango pulp in the sheet like texture) processing. Here, all these four drying methods were studied to determine the effect of drying on mango leather processing. RP-HPLC and FTIR were studied for analysis of polyphenol profile and predominant functional groups in raw and processed samples. The phytochemical analysis and medicinal properties (antioxidant, anti-diabetic, and anti-inflammatory activity) of all five mango samples were studied. The bioinformatics approach was studied to evaluate the bioactive potential of the phytochemicals derived from the samples. Freeze-dried mango leather was found to be the highest in DPPH (74.23%) and Superoxide (66.04%) activity, though raw mango pulp was observed with the highest H₂O₂ activity (73.24%). Gallic acid was the predominant phenolic acid present in all five samples and it was maximum in the case of freeze-dried sample (2.76 ± 0.04 mg/100 g MD). On the other hand, quercetin was the predominant flavonoid, it was found maximum for freeze-dried sample (3.93 ± 0.21 mg/100 g MD).

Chitosan and glyceryl monooleate nanostructures containing gallic acid isolated from amla fruit: targeted delivery system

Gallic acid, active constituent of amla fruit its natural abundance with beneficial multi actions in body make them attractive for clinical applications. In present study, we focused on extracting, separating and characterizing gallic acid from amla and further formulated into chitosan nanoparticles, so bring it to increase its aqueous solubility and thereby bioactivity. Gallic acid nanoparticles were prepared by using poloxamer 407, chitosan and Glyceryl Monooleate (GMO) using probe sonicator and high pressure homogenization method. Prepared nanoparticles were characterized by particle size, zeta potential, DSC, XRD, SEM, entrapment efficiency, loading content, in-vitro release and stability study. They showed approximately 76.80% encapsulation of gallic acid with average size of 180.8 ± 0.21 nm, and zeta potential +24.2 mV. The cumulative in vitro drug release upto 24 hrs 77.16% was achieved suggesting that from all our findings, it can be concluded that work will facilitate extraction, design and fabrication of nanoparticles for protection and sustained release of gallic acid particularly to colonic region.

Co-Solvent Selection for Supercritical Fluid Extraction (SFE) of Phenolic Compounds from Labisia pumila

A preliminary study was conducted to study the effects of different types and concentrations of co-solvents based on yield, composition and antioxidants capacity of extract prior to optimization studies of supercritical fluid extraction (SFE) of Labisia pumila (locally referred to as 'kacip fatimah'). The following co-solvents were studied prior to the optimization of supercritical carbon dioxide (SC-CO2) technique: ethanol, water, methanol, as well as aqueous solutions of ethanol-water and methanol-water (50% and 70% v/v). By using the selected co-solvents, identification of phenolic acids (gallic acid, methyl gallate and caffeic acid) was determined by using High-Performance Liquid Chromatography (HPLC). Then, the antioxidant capacity was evaluated by using three different assays: total phenolic content (TPC), ferric reducing/antioxidant power (FRAP) and free radical-scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). SC-CO2 with 70% ethanol-water co-solvent was superior in terms of a higher combination of phenolic compounds extracted and antioxidants capacity. Overall, SC-CO2 with co-solvent 70% ethanol-water technique was efficient in extracting phenolic compounds from L. pumila, and thus the usage of this solvent system should be considered for further optimization studies.

Dendrimer Nanodevices and Gallic Acid as Novel Strategies to Fight Chemoresistance in Neuroblastoma Cells

Human neuroblastoma (NB), a pediatric tumor inclined to relapse, after an initial response to therapy, usually develops resistance. Since several chemotherapeutics exert anticancer effect by increasing reactive oxygen species (ROS), NB cells overproduce antioxidant compounds becoming drugs-resistant. A strategy to sensitize NB cells to chemotherapy involves reducing their antioxidant defenses and inducing ROS overproduction. Concerning this, although affected by several issues that limit their clinical application, antioxidant/pro-oxidant polyphenols, such as gallic acid (GA), showed pro-oxidant anti-cancer effects and low toxicity for healthy cells, in several kind of tumors, not including NB. Herein, for the first time, free GA, two GA-dendrimers, and the dendrimer adopted as GA reservoir were tested on both sensitive and chemoresistant NB cells. The dendrimer device, administered at the dose previously found active versus sensitive NB cells, induced ROS-mediated death also in chemoresistant cells. Free GA proved a dose-dependent ROS-mediated cytotoxicity on both cell populations. Intriguingly, when administered in dendrimer formulations at a dose not cytotoxic for NB cells, GA nullified any pro-oxidant activity of dendrimer. Unfortunately, due to GA, nanoformulations were inactive on NB cells, but GA resized in nanoparticles showed considerable ability in counteracting, at low dose, ROS production and oxidative stress, herein induced by the dendrimer.

Application of Ficus carica L. and Solanum incanum L. Extracts in Coagulation of Milk: The Case of Traditional Practice in Ab'ala Area, Afar Regional State, Ethiopia

People living in and around Ab'ala area of the Afar Regional State, Ethiopia, have a traditional practice of applying Ficus carica leaf and Solanum incanum fruit extracts to milk in order to coagulate it as soon as possible. Thus, to investigate the role of the extracts in the coagulation of milk and their health threats, the milk-clotting activity, phytochemical screening tests, antimicrobial activities by the agar well diffusion method, and heavy metal content by ICP-OES technique were determined. Accordingly, both Ficus carica and Solanum incanum were found to possess phenolics, saponins, and tannins. Likewise, positive tests for flavonoid in Ficus carica and alkaloid in Solanum incanum were observed. However, no terpenoids, glycosides, and oxalates were detected in the plants. Moreover, the crude and concentrated enzyme extracts of the plants exhibited clotting activity. In this regard, the enzyme extracts of Ficus carica were superior with the highest clotting activity of 1.20 U. On the other hand, ethanol and chloroform extracts of the samples showed inhibition zones against all tested microorganisms except their chloroform extract which did not exhibit inhibition against Escherichia coli and Aspergillus niger. Likewise, the metals Cr, Cd, Mn, Cu, and Fe were detected in the plant samples, with the Mn content of 3.67 ± 0.10 mg per kg of dry weight of the plant in Ficus carica being the highest. Indeed, the level of the heavy metal contents is considerably lower than those maximum permissible limits set by international standards. On the other hand, no Pb and Zn were detected in the plant samples. Therefore, the higher clotting activity of the enzyme extracts was an indicator that enzymes, rather than other phytochemicals, are the most probable agents responsible for the milk-clotting ability of the plants, resulting in the formation of cheese. Furthermore, the growth inhibition to most of the test microbes is a manifestation that bacterial fermentation is not a means of clotting the milk as bacteria introduced to the milk would be killed by the sample extracts. Moreover, the use of the plants in the coagulation process would not pose health threats as far as oxalate and metal toxicity is concerned.

Photocatalytic degradation of synthetic food dye, sunset yellow FCF (FD&C yellow no. 6) by Ailanthus excelsa Roxb. possessing antioxidant and cytotoxic activity

The purpose of our work is to identify the bioactive compounds of bark and leaves extract from Ailanthus excelsa Roxb. and to explore its effectiveness against synthetic food dye. The presence of primary and secondary metabolites was confirmed by carrying out phytochemicals analysis. With the prior knowledge accessible on the indispensable secondary metabolites holding antioxidant and cytotoxicity activity, the quantitative screening of total phenolic and flavonoid content in methanolic and aqueous extract of bark and leaves from Ailanthus excelsa were done. Comparatively, a higher value of flavonoid (161±0.3μg/mg) and phenolic acid content (152.4±0.14μg/mg) was found in bark extract. By FTIR analysis, the characteristic peak was obtained at 1581.63 and 1598.99cm^-1 confirmed the presence of functional groups associated to flavonoids and other phenolic groups respectively. In bark extract, 81% of DPPH inhibition was observed when compared to ascorbic acid (standard) 92% of free radical scavenging activity. Bark extract from Ailanthus excelsa exhibited 71% cytotoxicity against HeLa cell line (cervical cancer). In examining the toxicity level of crude extracts with red blood cells (RBC), the bark extract was showed a very less (2.8%) haemolytic activity. They also showed maximum zone of inhibition in antibacterial activity i.e. 13±0.5mm against Escherichia coli culture. At a concentration of 10mg/mL of crude extract from A. excelsa, 55% degradation of sunset yellow dye was observed. It concludes that, the compounds present in the A. excelsa, especially the bark extract showed better photocatalytic, haemolytic, antioxidant, cytotoxicity and antibacterial activity when compared to leaves extract.

Instant green synthesis of silver-based herbo-metallic colloidal nanosuspension in Terminalia bellirica fruit aqueous extract for catalytic and antibacterial applications

In the present study, microwave-assisted, optimized, instant, Terminalia bellirica fruit extract-mediated green synthesis of colloidal silver nanoparticles (AgNPs) has been reported. The synthesized AgNPs were characterized by UV–Vis spectroscopy, FTIR, Zetasizer, FESEM, EDX and XRD. The characteristic surface plasmon peak of reaction mixture at 406 nm confirmed the synthesis of AgNPs. The FTIR studies confirmed phytoconstituents were responsible for the synthesis and stability of AgNPs. The FESEM, EDX and XRD analysis revealed the presence of spherical silver nanoparticles of mean diameter ≤20.6 nm with face-centered cubic crystalline structure. These AgNPs showed notable catalytic activity in reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH₄. The synthesized AgNPs showed potential antibacterial and antibiofilm activity against bacterial pathogens like Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. Thus, these synthesized AgNPs can open avenues for the development of AgNP-based efficient nanocatalyst and potent nanomedicine in future.

Gallic Acid: Review of the Methods of Determination and Quantification

Gallic acid (3,4,5 trihydroxybenzoic acid) is a secondary metabolite present in most plants. This metabolite is known to exhibit a range of bioactivities including antioxidant, antimicrobial, anti-inflammatory, and anticancer. There are various methods to analyze gallic acid including spectrometry, chromatography, and capillary electrophoresis, among others. They have been developed to identify and quantify this active ingredient in most biological matrices. The aim of this article is to review the available information on analytical methods for gallic acid, as well as presenting the advantages and limitations of each technique.