Antioxidant Properties Of Plant Extracts Research Articles

Inhibition of Oral Pathogenic Bacteria, Suppression of Bacterial Adhesion and Invasion on Human Squamous Carcinoma Cell Line (HSC-4 Cells), and Antioxidant Activity of Plant Extracts from Acanthaceae Family.

Medicinal plants have traditionally been used to treat various human diseases worldwide. In this study, we evaluated the leaf extracts of plants from the Acanthaceae family, specifically Clinacanthus nutans (Burm.f.) Lindau, Thunbergia laurifolia Lindl., and Acanthus ebracteatus Vahl., for their compounds and antioxidant activity. The ethanolic extracts of A. ebracteatus showed the highest total phenolic content at 22.55 mg GAE/g extract and the strongest antioxidant activities, with IC50 values of 0.24 mg/mL and 3.05 mg/mL, as determined by DPPH and ABTS assays. The antibacterial efficacy of these extracts was also tested against Streptococcus pyogenes, Streptococcus mutans, Staphylococcus aureus, and Klebsiella pneumoniae. The diameters of the inhibition zones ranged from 14.7 to 17.3 mm using the agar well diffusion method, with MIC and MBC values ranging from 7.81 to 250 mg/mL. Anti-biofilm formation, antibacterial adhesion, and antibacterial invasion assays further demonstrated that these medicinal plant extracts can inhibit bacterial biofilm formation and prevent the adhesion and invasion of oral pathogenic bacteria on the human tongue squamous cell carcinoma-derived cell line (HSC-4 cells). The ethanolic extracts of C. nutans and A. ebracteatus were able to inhibit the gtfD and gbp genes, which facilitate biofilm formation and bacterial adherence to surfaces. These findings provide new insights into the antibacterial and antioxidant properties of plant extracts from the Acanthaceae family. These activities could enhance the clinical and pharmaceutical applications of plant extracts as an alternative therapy for bacterial infections and a dietary supplement.

Unveiling the Neuroprotective Potential of Date Palm (Phoenix dactylifera): A Systematic Review.

Background: Neurodegenerative diseases primarily afflict the elderly and are characterized by a progressive loss of neurons. Oxidative stress is intricately linked to the advancement of these conditions. This study focuses on Phoenix dactylifera (P. dactylifera; Family: Arecaceae), commonly known as "Ajwa," a globally cultivated herbal plant renowned for its potent antioxidant properties and reported neuroprotective effects in pharmacological studies. Method: This comprehensive systematic review delves into the antioxidant properties of plant extracts and their phytochemical components, with a particular emphasis on P. dactylifera and its potential neuroprotective benefits. Preferred reporting items for systemic reviews and meta-analysis (PRISMA) were employed to review the articles. Results: The study includes 269 articles published in the literature and 17 were selected after qualitative analysis. The growing body of research underscores the critical role of polyphenolic compounds found in P. dactylifera, which significantly contribute to its neuroprotective effects through antioxidant mechanisms. Despite emerging insights into the antioxidant actions of P. dactylifera, further investigation is essential to fully elucidate the specific pathways through which it confers neuroprotection. Conclusions: Like many other plant-based supplements, P. dactylifera's antioxidant effects are likely mediated by synergistic interactions among its diverse bioactive compounds, rather than by any single constituent alone. Therefore, additional preclinical and clinical studies are necessary to explore P. dactylifera's therapeutic potential comprehensively, especially in terms of its targeted antioxidant activities aimed at mitigating neurodegenerative processes. Such research holds promise for advancing our understanding and potentially harnessing the therapeutic benefits of P. dactylifera in neuroprotection.

Exploring Nutraceuticals: A Comprehensive Examination of Inception, Thematic Mapping, Evolution, Emerging Trends, and Gaps

Nutraceuticals (NCs) refer to food or dietary components that include medicinal or health-promoting properties, potentially aiding in preventing and managing specific diseases. Nutraceutical research (NCR) has made significant strides, but several gaps still need to be addressed. The study's main objective is to analyze the inception and current state of NCs, identify research gaps, and map out potential areas for future investigation in the field of NCR. The study utilized the Scopus database to gather bibliographic data through MesH-generated keywords. The search encompassed English-language original research without limitations on chronology or geography. The PRISMA methodology was employed to refine the search results. The Bibliometrix software tool, based on the R programming language, analyzes 16,030 research publications. Since 1993, NCR has experienced exponential growth of 27.27% (R2 = 0.929). Italy and the United States are the leading countries regarding publications and citations. The most prolific scholar in NCR is McClements, D.J. The research findings highlight that the antioxidant properties of plant extracts, pathophysiology of diet- and age-induced diabetes, pharmaceutical formulations, and drug delivery routes are the most cited research directions. Thematic mapping of NCR reveals a need for motor and emerging themes, with key clusters including "nutraceuticals," "antioxidant activity," and "curcumin." The thematic evolution of NCR's themes experienced a turning point in 2020. As a result, trending topics in NCR include Castanea sativa, authentication, lipophilicity, bioactive compounds, molecular docking, COVID-19, autophagy, gut microbiota, and sustainability. The study helps bridge research gaps and promotes the safe and effective use of nutraceuticals for human health. It provides valuable benefits for researchers, including identifying interesting authors, popular research areas, and collaboration opportunities. Furthermore, the findings can inform decision-makers in making strategic and informed decisions regarding policy, finance, and resource allocation in the field of nutraceutical research.

Chemotaxonomy, antibacterial and antioxidant activities of selected aromatic plants from Tabuk region-KSA

Chemotaxonomy is a valuable tool for obtaining taxonomic insights, which are most effectively employed in combination with other forms of data to establish a system of classification that closely reflects natural connections. The utilization of plant secondary metabolites possessing diverse therapeutic qualities signifies the growing exploitation of natural products in the medical discipline. The objectives of the current study encompassed the identification of phytochemicals in the extracts of nine species of medicinal plants, the examination of their chemotaxonomic properties, and the assessment of the antibacterial and antioxidant capabilities exhibited by the extracts. GC-MS technology was employed for the identification of phytochemical compounds. The study utilized ClassyFire, an automated chemical classification system that incorporates an extensive and computable classification, to categorize chemicals. The chemical classification of plants was examined by the application of principal component analysis (PCA) and cluster analysis (CA). The bactericidal properties of plants were assessed against four harmful bacterial species using the disc diffusion technique. The antioxidant properties of plant extracts were assessed employing the DPPH free radical scavenging methodology, and the half maximal effective concentration (EC50) was determined using dose response models. The calculator being referred to is the Quest Graph™ EC50 Calculator. In the plant extracts, the analysis disclosed the occurrence of 160 phytochemicals, classified into 36 phytochemical classes. The results of CA and PCA demonstrated the proximity and associations among Asteraceae species, while indicating the divergence of the two Lamiaceae species. Achillea fragrantissima and Ducrosia flabellifolia demonstrated the most diversity in phytochemical classes, while Thymus vulgaris displayed the highest level of dominance. Pulicaria undulata and T. vulgaris had the most notable antibacterial activity. D. flabellifolia and P. incisa demonstrated the highest levels of antioxidant activity. Ethanol exhibited superior antibacterial efficacy compared to other solvents. The remarkable biological activities exhibited by these plant extracts can be ascribed to the copious presence of certain chemicals, predominantly sesquiterpenoids, monoterpenoids, benzene and its derivatives, naphthalenes, fatty acyls, and phenols. The susceptibility of Gram-positive bacterial species to plant extracts was shown to be higher in comparison to Gram-negative bacterial species.

Phenolic characterization and antioxidant activity of Chrysanthemum indicum and Opisthopappus Shih during different growth stages.

In this paper, a comparative study on the phenolics and antioxidant activity of C. indicum and O. shih during growth were investigated. Antioxidant properties of plant extracts were tested out using DPPH and ABTS assays. The characterization of potential phytochemicals was carried out using Fourier transform infrared (FT-IR) spectroscopy. Total phenolics (TPC) and total flavonoid content (TFC) were measured using Folin-Ciocalteau and aluminum chloride colorimetric methods, respectively.An HPLC method was used to simultaneously quantify five phenolic compounds, including chlorogenic acid, luteolin, rutin, quercetin, and apigenin. Results indicated that the Trolox equivalent antioxidant activity (TEAC) values of C. indicum and O. shih had extremely large variations at different growth stages. The most abundant phenolics and potent antioxidant activity of two related plants appear at the early vegetative and then flowering stages. Antioxidant activities and phenolic content of O. shih were higher than those of corresponding organs of C. indicum at the same collection time. The whole plant of O. shih, especially its leaves and flowers, are good candidates for obtaining nutraceuticals and functional food ingredients.

Comparative Amino Acid Profile and Antioxidant Activity in Sixteen Plant Extracts from Transylvania, Romania.

In addition to the naturopathic medicines based on the antiseptic, anti-inflammatory, anticancer, or antioxidant properties of plant extracts that have been capitalized upon through the pharmaceutical industry, the increasing interest of the food industry in this area requires potent new materials capable of supporting this market. This study aimed to evaluate the in vitro amino acid contents and antioxidant activities of ethanolic extracts from sixteen plants. Our results show high accumulated amino acid contents, mainly of proline, glutamic, and aspartic acid. The most consistent values of essential amino acids were isolated from T. officinale, U. dioica, C. majus, A. annua, and M. spicata. The results of the 2,2-diphenyl-1-pycrylhydrazyl (DPPH) radical scavenging assay indicate that R. officinalis was the most potent antioxidant, followed by four other extracts (in decreasing order): T. serpyllum, C. monogyna, S. officinalis, and M. koenigii. The network and principal component analyses found four natural groupings between samples based on DPPH free radical scavenging activity content. Each plant extracts' antioxidant action was discussed based on similar results found in the literature, and a lower capacity was observed for most species. An overall ranking of the analyzed plant species can be accomplished due to the range of experimental methods. The literature review revealed that these natural antioxidants represent the best side-effect-free alternatives to synthetic additives, especially in the food processing industry.

Antioxidant Activity and Photosynthesis Efficiency in Melissa officinalis Subjected to Heavy Metals Stress

The aim of this study was to assess influence of cadmium and zinc treatments on antioxidant activity combined with the photosynthesis efficiency in a popular herb lemon balm (Melissa officinalis L.). Plants were grown under greenhouse conditions by the pot method. The Mn, Cu, Cd, and Zn contents in soil and plants were measured by HR-CS FAAS. The activity of net photosynthesis, stomatal conductance, transpiration rate, intercellular CO2, and index of chlorophyll in leaves were determined for all investigated species. Reduction of the net photosynthesis was observed for cultivations subjected to either Zn or Cd treatments. Phenolic contents were determined by the chemical Folin-Ciocalteu method, while enhanced voltammetric analysis was applied to assess the antioxidant properties of plant extracts. Both of these approaches yielded similar results. Herbal extracts had exceptional antioxidant capacities and were good scavengers of free radicals and reactive oxygen species. Structural similarity of cadmium and zinc facilitated their mutual structural exchange and prompted substantial expansion of phenolics under the mixed Zn and Cd treatments.

Bioactivity evaluation of least explored traditionally acclaimed medicinally potent herb Nanorrhinum ramosissimum(Wall.) Betsche

Present study analysed the therapeutic potential of traditionally acclaimed medicinal herb Nanorrhinum ramosissimum, using plant parts extracted with different solvents (10 mg/mL). Shoot extracts exhibited comparatively better antimicrobial properties, in comparison to root extracts. Total phenolic content was estimated, to ascertain its dependency on antioxidant properties of plant extracts. Antioxidant assay revealed promising results in comparison to IC50 value of standard ascorbic acid (52.2±0.07 µg/mL), for methanolic extracts of shoot (61.07±0.53 µg/mL and 64.33±0.33 µg/mL) and root (76.705±0.12 µg/mL and 89.73±0.28 µg/ mL) for in vivo and in vitro regenerants respectively. Correlation coefficient R2 values ranged between 0.90-0.95, indicating a positive correlation between phenolic contents and antioxidant activity. Plant extracts were also able to inhibit DNA oxidative damage again indicating their antioxidative potential. Antidiabetic potential was confirmed by alpha amylase inhibition assay where shoot methanolic extracts (invivo, in vitro) exhibited the best IC50 values (54.42±0.16 µg/mL, 66.09±0.12 µg/mL) in comparison to standard metformin (41.92±0.08 µg/mL). Ethanolic extracts of roots (in vitro, invivo) exhibited the relative IC50 values (88.97±0.32µg/mL,96.63±0.44 µg/mL) indicating that shoot parts had a better alpha amylase inhibition property; thus proving the herb’s bioactive potential and its prospective therapeutic source for curing various ailments.

Plant Extracts for Type 2 Diabetes: From Traditional Medicine to Modern Drug Discovery.

Type 2 diabetes mellitus (T2DM) is one of the largest public health problems worldwide. Insulin resistance-related metabolic dysfunction and chronic hyperglycemia result in devastating complications and poor prognosis. Even though there are many conventional drugs such as metformin (MET), Thiazolidinediones (TZDs), sulfonylureas (SUF), dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon like peptide 1 (GLP-1) and sodium-glucose cotransporter-2 (SGLT-2) inhibitors, side effects still exist. As numerous plant extracts with antidiabetic effects have been widely reported, they have the potential to be a great therapeutic agent for type 2 diabetes with less side effects. In this study, sixty-five recent studies regarding plant extracts that alleviate type 2 diabetes were reviewed. Plant extracts regulated blood glucose through the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway. The anti-inflammatory and antioxidant properties of plant extracts suppressed c-Jun amino terminal kinase (JNK) and nuclear factor kappa B (NF-κB) pathways, which induce insulin resistance. Lipogenesis and fatty acid oxidation, which are also associated with insulin resistance, are regulated by AMP-activated protein kinase (AMPK) activation. This review focuses on discovering plant extracts that alleviate type 2 diabetes and exploring its therapeutic mechanisms.

Effects of solid-state fermentation and extraction solvents on the antioxidant properties of lentils

Abstract Plant-based foods may have their nutritional and biological properties improved through biotransformation processes; becoming more beneficial to health and attractive to consumers. Fermentation is a process widely applied to legumes which can improve their antioxidant properties. This work investigated the antioxidant potential (ABTS, DPPH, and FRAP methods) and total phenolic compound content (TPC) of extracts derived from lentils fermented with Aspergillus oryzae; using water, methanol and ionic liquids (choline acetate, choline hydroxide and choline lactate) as solvents. The results showed that the antioxidant properties and TPC content of the extracts obtained after fermentation were significantly (p ≤ 0.05) higher than those of non-fermented samples. Approximate increases of 143, 54, 52 and 500% were detected for ABTS, DPPH, FRAP and TPC after fermentation, respectively. The solvents applied in our work demonstrated different abilities in antioxidant and phenolic compound recovery. The foremost positive results were obtained using water as a solvent for extraction from fermented lentils. In addition, important information about the use of ionic liquids for recovery and their effects on the content of antioxidant properties of plant extracts was provided.

Naturally present metal ions in plants could interfere with common antioxidant assays

Most of the commonly applied assays used to assess antioxidant properties of plant extracts exploit the ability of some biologically active metabolites to participate in oxidation-reduction reactions with metal ions. On the other hand, most plants contain different chelated metal ions whose levels depend on the geographic origin, soil, and environmental pollutions. In this study the levels of redox-active metal ions in three plant sources were measured and extracts of these botanicals were treated with ChelexⓇ – an ion exchanger that is noteworthy for its ability to bind transition metal ions. The original and chelated extracts were subjected to three antioxidant assays based on single electron transfer. The results obtained showed statistically significant differences between the original and Chelex-treated extracts suggesting that the naturally present metal ions could interfere with the results of the three most commonly applied antioxidant methods.•The proposed pre-analytical procedure is simple and does not require special instrumental equipment.•Preliminary depletion of redox active metal ions, namely iron and copper ions could improve reproducibility of the analytical methods.•The method allows a more reliable comparison of antioxidant properties of particular botanical species from different geographic regions.

Estimation of Total Antioxidant Capacity of Hydroalcoholic Extract from the Matricaria Ineora By an Electrochemical Method

Plants have been used as medicines for thousands of years. They have been applied for the preparation of ingredients and drugs in the treatment of diseases [1-4]. Clinical studies revealed that a diet rich in fruits and vegetables decreased risk of cardiovascular diseases and cancers. These beneficial health effects have emanated from the presence of antioxidant compounds in the plants. Oxidation is one of the most important chemical and biochemical processes. Free radicals can oxidize nucleic acids, proteins and lipids, initiating degenerative diseases. Antioxidants such as phenolic compounds are compounds known to react with free oxygen radicals and thus preventing their cell-damaging action. Therefore, screening for antioxidant properties of plant extracts is prominent in their pharmaceutical applications. Different methods have been reported for the evaluation of antioxidant capacity of medicinal plant extracts. In the present research cyclic voltammetry have been used for antioxidant screening of medicinal plant extracts. Since, electrochemical techniques are low-cost and enable rapid analysis of sample. Cyclic voltammetry on carbon nanotube modified electrode appears to be a suitable tool in antioxidant assays. It can provide information about the number of compounds redox states and the stability of these states [5]. In this work, leaves of matricaria ineora, as a medicinal plant, were dried at shadow and at room temperature. The 3.0 g powdered leaves of the plant were macerated with 50 mL of ethanol:water (20:80) for 24 h and sonicated for 12 min. The extracts were filtered using filter paper. The voltammograms were obtained for electrochemical oxidation of antioxidant compounds on the bare and modified electrodes in two separate experiments in buffer solution (pH 7.2). It have been compared the cyclic voltammograms of matricaria ineora extract at a bare and single-walled carbon nanotube (SWCNT) modified glassy carbon electrodes. The cyclic voltammetric responses for electrochemical oxidation of extract on the bare electrode containing one pair redox peak and modified electrode containing two pair redox peaks at 100 mV/s. The peak current increased significantly on the SWNTs modified electrode as compared with the bare electrode. The electrode surface modification with SWCNTs augmented its effective surface area and the oxidation currents of antioxidants. The first redox peaks are related to compounds which also were oxidized on the bare glassy carbon electrode. Second peaks are related to compounds which cannot oxidize on the bare electrode but due to nanotubes electrocatalysis property oxidized them on the modified electrode.

In vitro antioxidant and anticancer effects of solvent fractions from Prunella vulgaris var. lilacina.

BackgroundRecently, considerable attention has been focused on exploring the potential antioxidant properties of plant extracts or isolated products of plant origin. Prunella vulgaris var. lilacina is widely distributed in Korea, Japan, China, and Europe, and it continues to be used to treat inflammation, eye pain, headache, and dizziness. However, reports on the antioxidant activities of P. vulgaris var. lilacina are limited, particularly concerning the relationship between its phenolic content and antioxidant capacity. In this study, we investigated the antioxidant and anticancer activities of an ethanol extract from P. vulgaris var. lilacina and its fractions.MethodsDried powder of P. vulgaris var. lilacina was extracted with ethanol, and the extract was fractionated to produce the hexane fraction, butanol fraction, chloroform fraction and residual water fraction. The phenolic content was assayed using the Folin-Ciocalteu colorimetric method. Subsequently, the antioxidant activities of the ethanol extract and its fractions were analyzed employing various antioxidant assay methods including DPPH, FRAP, ABTS, SOD activity and production of reactive oxygen species. Additionally, the extract and fractions were assayed for their ability to exert cytotoxic activities on various cancer cells using the MTT assay. We also investigated the expression of genes associated with apoptotic cell death by RT-PCR.ResultsThe total phenolic contents of the ethanol extract and water fraction of P. vulgaris var. lilacina were 303.66 and 322.80 mg GAE/g dry weight (or fractions), respectively. The results showed that the ethanol extract and the water fraction of P. vulgaris var. lilacina had higher antioxidant content than other solvent fractions, similar to their total phenolic content. Anticancer activity was also tested using the HepG2, HT29, A549, MKN45 and HeLa cancer cell lines. The results clearly demonstrated that the P. vulgaris var. lilacina ethanol extract induced significant cytotoxic effects on the various cancer cell lines, and these effects were stronger than those induced by the P. vulgaris var. lilacina solvent fractions. We also investigated the expression of genes associated with apoptotic cell death. We confirmed that the P. vulgaris var. lilacina ethanol extract and water fraction significantly increased the expression of p53, Bax and Fas.ConclusionsThese results suggest that the ethanol extract from P. vulgaris var. lilacina and its fractions could be applied as natural sources of antioxidants and anticancer activities in food and in the pharmaceutical industry.

A simple electrochemical method for the rapid estimation of antioxidant potentials of some selected medicinal plants.

Clinical and Epidemiological studies have shown that a diet rich in fruits and vegetables is associated with a decreased risk of cardiovascular diseases, cancers and other related disorders. These beneficial health effects have been attributed in part to the presence of antioxidants in dietary plants. Therefore screening for antioxidant properties of plant extracts has been one of the interests of scientists in this field. Different screening methods have been reported for the evaluation of antioxidant properties of plant extracts in the literature. In the present research a rapid screening method has been introduced based on cyclic voltammetry for antioxidant screening of some selected medicinal plant extracts. CYCLIC VOLTAMMETRY OF METHANOLIC EXTRACTS OF SEVEN MEDICINAL PLANTS: Buxus hyrcana, Rumex crispus, Achillea millefolium, Zataria multiflora, Ginkgo biloba, Lippia citriodora and Heptaptera anisoptera was carried out at different scan rates. Based on the interpretation of voltammograms, Rumex crispus, Achillea millefolium and Ginkgo biloba showed higher antioxidant capability than the others while Lippia citriodora contained the highest amount of antioxidants. Cyclic voltammetry is expected to be a simple method for screening antioxidants and estimating the antioxidant activity of foods and medicinal plants.

Antioxidant properties of plant extracts: an EPR and DFT comparative study of the reaction with DPPH, TEMPOL and spin trap DMPO

This work presents a comparative study of the antioxidant activity of extracts from nine plant species belonging to the Brazilian flora - Swartzia langsdorffii, Machaerium villosum, Pterogyne nitens, Pera glabrata, Aegiphyla sellowiana, Copaifera langsdorffii, Chrysophyllum inornatum, Iryanthera juruensis, Didymopanax venosum - acting on the free-radicals DPPH (2,2-diphenyl-1-picrylhydrazyl) and TEMPOL (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy-1-oxyl) by electron paramagnetic resonance (EPR), and acting on the hydroxyl radical (OH•) by the spin-trapping technique generated by a Fenton reaction. Results showed that the extracts of Iryanthera juruensis and Chrysophyllum inornatum display the strongest antioxidant activities. The results of scavenging tests were clarified by computational calculations - density functional theory (DFT), local density approximation (LDA) with SIESTA code - indicating that the energy released in the reduction reaction of TEMPOL is less than DPPH. Due to its availability and cost DPPH is more often used in these tests than TEMPOL, however TEMPOL should be considered when studying processes dealing with smaller energies.

Investigations of the antioxidant properties of plant extracts using a DNA-electrochemical biosensor

In this work, the results of a method based on an electrochemical biosensor to detect DNA damage in vitro for the evaluation of the antioxidant properties of plant extracts are reported. The biosensor consisted of a dsDNA immobilized on a screen-printed electrode surface (SPE). DNA damage was promoted by the generation of the *OH radicals via Fenton-type reaction. The interaction of the radical species with immobilised DNA in the absence and presence of antioxidants was evaluated by means of changes in the guanine oxidation peak obtained by square wave voltammetry. The results demonstrated that the DNA-based biosensor is suitable as a rapid screening test for the evaluation of antioxidant properties of samples.