Plant Phenolic Compounds Research Articles

GREEN SYNTHESIS AND BIOCHEMICAL PROPERTIES OF PROPOLIS BASED SILVER NANOPARTICLES

Propolis is a substance collected by honey bees from different parts of plants. Honey bees store it in their hives in order to defend against different threats. Propolis is a bee-product rich in plant waxes, esters, fatty acids, volatile components and phenolic compounds. It`s rich phenolic content makes propolis a potential reducer for Ag+ to Ag. In this study, propolis-based silver nanoparticles were obtained using the green synthesis technique. It was determined that the obtained silver nanoparticles had a maximum absorbance at 425 nm and their sizes ranged from 67 to 75 nm. When the FT-IR data of propolis extract is examined, the band at 3200 cm-1 represents functional -OH groups, the band at 2919-2850 cm-1 represents C-H stretching, the band at 1634 cm-1 represents C=C, C=O or NH stretching, the band at 1508 cm-1 represents aromatic C=C stretching and the band at 1451 cm-1 originate from the C-H stretching of CH3, CH2, flavonoids and aromatic rings. Total phenolic content of propolis extract and silver nanoparticles was determined as 176.42±0.18 and 122.63±0.23 mg GAE/mL, respectively. IC50 value of P-AgNPs for α-amylase and α-glycosidase enzyme inhibition was defined as 47.08 ± 0.002 and 52.18 ± 0.001 µg/mL, respectively. Inhibition of α-Amylase and α-glycosidase is still a valid approach in the treatment of diabetes. The high inhibition effect of the obtained nanoparticles on the related enzymes shows that they have diabetes treatment potential. In addition, showing that cheap and abundant nanoparticles can be obtained by using propolis, this study may contribute to the development of new products containing nanoparticles that can be used in apitherapy applications.

Phenolic Compound Ethyl 3,4-Dihydroxybenzoate Retards Drug Efflux and Potentiates Antibiotic Activity.

The World Health Organization indicated that antibiotic resistance is one of the greatest threats to health, food security, and development in the world. Drug resistance efflux pumps are essential for antibiotic resistance in bacteria. Here, we evaluated the plant phenolic compound ethyl 3,4-dihydroxybenzoate (EDHB) for its efflux pump inhibitory (EPI) activity against drug-resistant Escherichia coli. The half-maximal inhibitory concentration, modulation assays, and time-kill studies indicated that EDHB has limited antibacterial activity but can potentiate the activity of antibiotics for drug-resistant E. coli. Dye accumulation/efflux and MALDI-TOF studies showed that EDHB not only significantly increases dye accumulation and reduces dye efflux but also increases the extracellular amount of antibiotics in the drug-resistant E. coli, indicating its interference with substrate translocation via a bacterial efflux pump. Molecular docking analysis using AutoDock Vina indicated that EDHB putatively posed within the distal binding pocket of AcrB and in close interaction with the residues by H-bonds and hydrophobic contacts. Additionally, EDHB showed an elevated postantibiotic effect on drug-resistant E. coli. Our toxicity assays showed that EDHB did not change the bacterial membrane permeability and exhibited mild human cell toxicity. In summary, these findings indicate that EDHB could serve as a potential EPI for drug-resistant E. coli.

Assessing the Ameliorative Effect of Selenium Cinnamomum verum, Origanum majorana, and Origanum vulgare Nanoparticles in Diabetic Zebrafish (Danio rerio).

Cinnamomum verum, Origanum majorana, and Origanum vulgare have been used in traditional medicine for a long time to treat diabetes because of their promising therapeutic effects. The combination of these plants (COO) was tested to improve their efficacy using selenium nanoparticles (Se-COO-NPs) and gum Arabic (GA) as stabilizers for sustained release. Phenolic compounds of plants were identified using liquid chromatography–mass spectrometry (LC–MS/MS). GA-Se-COO-NPs were characterized by spectroscopic and microscopic methods and evaluated in diabetic zebrafish. The ultraviolet spectrum was assessed to confirm the formation of plasmon resonance at 267 nm. The obtained particle size of selenium nanospheres was 65.76 nm. They were maintained in a stable form for 5 months at 4 °C. Transmission electron microscopy (TEM) images demonstrated the presence of individual spherical nanoparticles. Fourier transform infrared spectroscopy (FT-IR) showed the interaction between COO extract and selenium, exhibiting good entrapment efficiency (87%). The elemental analysis of COO extract and GA-COO-SeNPs confirmed that NPs were obtained. The zebrafish were exposed to a high glucose concentration for two weeks, and type 2 diabetes and oxidative stress responses were induced. In diabetic zebrafish, treatment with NPs showed antilipidemic and hypoglycemic effects, high survivability, and reduced levels of glucose, reactive oxygen species (ROS), and lipids in the blood. This group this had a higher survivorship rate than the diabetic control. The results demonstrated that GA-Se-COO-NPs have high antidiabetic potential, most likely because of the synergic effects of phenolic compounds and Se nanoparticles.

Comparative Determination of Phenolic Compounds in Arabidopsis thaliana Leaf Powder under Distinct Stress Conditions Using Fourier-Transform Infrared (FT-IR) and Near-Infrared (FT-NIR) Spectroscopy.

The increasing interest in plant phenolic compounds in the past few years has become necessary because of their several important physicochemical properties. Thus, their identification through non-destructive methods has become crucial. This study carried out comparative non-destructive measurements of Arabidopsis thaliana leaf powder sample phenolic compounds using Fourier-transform infrared and near-infrared spectroscopic techniques under six distinct stress conditions. The prediction analysis of 600 leaf powder samples under different stress conditions (LED lights and drought) was performed using PLSR, PCR, and NAS-based HLA/GO regression analysis methods. The results obtained through FT-NIR spectroscopy yielded the highest correlation coefficient () value of 0.999, with a minimum error (RMSEP) value of 0.003 mg/g, based on the PLSR model using the MSC preprocessing method, which was slightly better than the correlation coefficient () value of 0.980 with an error (RMSEP) value of 0.055 mg/g for FT-IR spectroscopy. Additionally, beta coefficient plots present spectral differences and the identification of important spectral signatures sensitive to the phenolic compounds in the measured powdered samples. Thus, the obtained results demonstrated that FT-NIR spectroscopy combined with partial least squares regression (PLSR) and suitable preprocessing method has a solid potential for non-destructively predicting phenolic compounds in Arabidopsis thaliana leaf powder samples.

Adventitious root culture of Plantago ovata Forssk. as a source of phenylethanoid glycosides

The investigations were targeted to obtain in vitro culture of Plantago ovata, which would be efficient in the production of plant biomass and phenolic compounds with multiple biological activities, like acteoside and plantamajoside - the main phenylethanoid glycosides present in the Plantago genus. In these experimental studies, roots were obtained by natural development from seedlings germinated in vitro and from in vitro multiplied shoots as well as by direct organogenesis on seedling leaf explants and indirect organogenesis from callus cultured on various explants. Callus-regenerated roots agitated in MS (Murashige and Skoog) liquid medium supplemented with phytohormones NAA (1-naphthaleneacetic acid) 0.25 mg/L and BAP (benzylaminopurine) 0.5 mg/L turned out to be a good growth system for root biomass production - mean increase of root fresh weight calculated on three following passages was 6641.07%. The quantitative screening of the root extract by HPTLC video densitometric method showed the content of acteoside 33.02 mg/g dry weight (d.w.) (538.9 mg/L of culture) and plantamajoside 6.39 mg/g d.w. (104.0 mg/L of culture) in root biomass obtained with the yield 16.32 g d.w. /L within 4 weeks. The content of those compounds in the in vitro shoots was significantly lower – 4.20 and 4.28 mg/g, d.w., respectively. Although the high level of acteoside in the root culture decreased in the following 8 weeks of the culture, it is still satisfactorily high (8.25 mg/g, d.w.). This is the first report on the adventitious root cultures of Plantago ovata and the content of those phenylethanoids in that well-grown plant material. The proposed approach provides an alternative to the soil-grown plants, source of plant metabolites, due to the possibility of the fast, regular and scalable production of plant biomass containing the compounds of interest as the main constituents.

Rosmarinic acid and hesperidin regulate gas exchange, chlorophyll fluorescence, antioxidant system and the fatty acid biosynthesis-related gene expression in Arabidopsis thaliana under heat stress

The impacts of exogenous rosmarinic acid (RA, 100 μM) and/or hesperidin (HP, 100 μM) were evaluated in improving tolerance on the gas exchange, chlorophyll fluorescence and efficiencies, phenomenological fluxes of photosystems, antioxidant system and gene expression related to the lipid biosynthesis under heat stress. For this purpose, Arabidopsis thaliana was grown under RA and HP with heat stress (S, 38 °C) for 24 h(h). As shown in gas exchange parameters, heat stress caused mesophyll efficiency and non-stomatal restrictions. Both alone and combined forms of RA and HP to stress-treated A. thaliana alleviated the disturbance of carbon assimilation, transpiration rate and internal CO2 concentrations. Stress impaired the levels of energy flow reaching reaction centers of PSII and the photon capture ability of active reaction centers. RA and/or HP enhanced photosystems' structural/functional characteristics and photosynthetic performance. Histochemical staining and biochemical analyses revealed that heat stress caused the oxidation in A. thaliana. By activating several defensive mechanisms, RA and/or HP could reverse the harm caused by radical production. Both alone and combined forms of RA and HP removed superoxide anion radical (O2•−) accumulation, inducing superoxide dismutase (SOD). The common enzyme that scavenged hydrogen peroxide (H2O2) at all three applications (S + RA, S + HP and S + RA + HP) was POX. Also, only RA could utilize the ascorbate (AsA) regeneration in response to stress, suggesting increased ascorbate peroxidase (APX), monodehydroascorbate (MDHAR) and dehydroascorbate (DHAR) activities. However, the regeneration/redox state of AsA and glutathione (GSH) did not maintain under S + HP and S + RA + HP. While RA had no positive influence on the saturated fatty acids under stress, HP increased the total saturated fatty acids (primarily palmitic acid). Besides, the combined application of RA + HP effectively created the stress response by increasing the expression of genes involved in fatty acid synthesis. The synergetic interactions of RA and HP could explain the increased levels of saturated fatty acids in combining these compounds. The data obtained from the study will contribute to the responses of phenolic compounds in plants to heat stress.

Effect of plant phenolic compounds on the hemocyte concentration and antioxidant enzyme activity in Hyphantria cunea (Drury, 1773) (Lepidoptera: Arctiidae) larvae infected by Hyphantria cunea granulovirus

The aim of this study was to determine the effects of phenolic substances in different plants (mulberry, apple, walnut and plum) on hemocyte counts and antioxidant enzyme activities of Hyphantria cunea larvae infected with Hyphantria cunea granulovirus (HycuGV) and uninfected. In the study, the phenolic contents of plant materials were firstly determined. Then, the effects of these ingredients on hemocyte counts and antioxidant enzyme activities of infected and uninfected larvae were determined. As a result of the study, the hemocyte counts of all groups increased with the infection was determined. In enzyme activity, the phenoloxidase (PO) activities of larvae fed on apple leaves and plum leaves containing rosmarinic acid and protocatechuic acid increased with infection was determined. The amounts of malondialdehyde (MDA) decreased in all groups as a result of viral infection. While the highest superoxide dismutase (SOD) and catalase (CAT) activities among both infected and uninfected larvae were in the plum groups with the highest amount of chlorogenic acid, the lowest glutathione peroxidase (GSH-Px) activities were also in these groups. All this showed that different phenolic contents of host plants affected the hemocyte counts and antioxidant enzyme activities of H. cunea larvae.

Chrysoeriol isolated from Melientha suavis Pierre with activity against the agricultural pest Spodoptera litura

BackgroundFlavonoids, a class of plant phenolic compounds, act as plant defense chemicals. Chrysoeriol is a naturally occurring flavonoid produced by Melientha suavis Pierre. The goal of this study was to investigate the insecticidal potential and mode of action of chrysoeriol isolated from M. suavis against Spodoptera litura (Fabricius).ResultsThe effects of chrysoeriol on second-instar S. litura larvae were determined by topical application. Chrysoeriol was highly toxic to S. litura (24- and 48-h LD50 values of ~ 6.99 and 6.51 µg/larva, respectively). Moreover, mode-of-action experiments demonstrated that this compound significantly decreased the activities of both detoxification-related enzymes [carboxylesterases (CarE) and glutathione S-transferase (GST)] and neurological enzymes (acetylcholinesterase).ConclusionsThese results indicate that chrysoeriol isolated from M. suavis could be used as a potential agent with activity against S. litura. However, it is necessary to determine the potential side effects on nontarget species for the further development of these novel insecticides.Graphical

Oviposition behaviour and biochemical response of an insect pest, Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae) to plant phenolic compound phloroglucinol

Phenolic compounds are the secondary metabolites (SMs) present in plants carrying different bioactivities. In the present study, we explored the influence of a phenolic compound namely phloroglucinol on oviposition behaviour and different biochemical entities of an insect pest Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae) using artificial diet. Phloroglucinol (IUPAC name: benzene-1,3,5-triol) affected the activity of antioxidant and detoxifying enzymes viz. superoxide dismutases (SOD), catalase (CAT), ascorbate peroxidases (APOX). dehydroascorbate reductase (DHAR), peroxidases (POX), phenol oxidase (PO), glutathione peroxidase (GPOX), glutathione S-transferase peroxidase (GSTpox), glutathione reductase (GR), glutathione S-transferase (GST) and esterases (EST) as well as the biological antioxidants viz. ascorbate content and glutathione. The lipid peroxide content (LP) and hydrogen peroxide content (H2O2) were significantly enhanced in the treated larvae indicating oxidative stress in the insect. Significant inhibition in oviposition was observed and effective repellency percentage increased with phloroglucinol treatment as compared to control. The oviposition deterrent activity and toxic effects of phloroglucinol on various biochemical parameters of Z. cucurbitae larvae revealed in the present study clearly confirms its suitability for use in pest management.

Inhibitory activities of grape bioactive compounds against enzymes linked with human diseases.

A quest for identification of novel, safe and efficient natural compounds, as additives in the modern food and cosmetic industries, has been prompted by concerns about toxicity and side effects of synthetic products. Plant phenolic compounds are one of the most documented natural products due to their multifarious biological applications. Grape (Vitis vinifera) is an important source of phenolic compounds such as phenolic acids, tannins, quinones, coumarins and, most importantly, flavonoids/flavones. This review crisply encapsulates enzyme inhibitory activities of various grape polyphenols towards different key human-ailment-associated enzymes: xanthine oxidase (gout), tyrosinase (hyperpigmentation), α-amylase and α-glucosidase (diabetes mellitus), pancreatic lipase (obesity), cholinesterase (Alzheimer's disease), angiotensin i-converting enzymes (hypertension), α-synuclein (Parkinson's disease) and histone deacetylase (various diseases). The review also depicts the enzyme inhibitory mechanism of various grape polyphenols and briefly discusses their stature as potential therapeutic and drug development candidates. KEY POINTS: • Nineteen major bioactive polyphenols from the grape/grape products and their disease targets are presented • Sixty-two important polyphenols as enzyme inhibitors from grape/grape products are presented • A thorough description and graphical presentation of biological significance of polyphenols against various diseases.

Oleacein Attenuates Lipopolysaccharide-Induced Inflammation in THP-1-Derived Macrophages by the Inhibition of TLR4/MyD88/NF-κB Pathway.

It is known that plant phenolic compounds exert anti-inflammatory activity through both anti-oxidant effects and modulation of pivotal pro-inflammatory factors. Recently, Olea europaea has been studied as a natural source of bioactive molecules; however, few studies have focused on the biological effect of oleacein (OLC), the most abundant secoiridoid. Therefore, the aim of this study was to investigate the potential anti-oxidant activity of OLC, as well as to study its anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated THP-1-derived macrophages. LPS brought a dramatic increase of both release and gene expression of pro-inflammatory cytokines (IL-6, IL-1β and TNF-α), as well as a decrease of anti-inflammatory ones (IL-10), the effects of which are reverted by OLC. Moreover, it reduced the levels of COX-2, NO and PGE2 elicited by LPS exposure in THP-1 macrophages. Interestingly, OLC modulated inflammatory signaling pathways through the inhibition of CD14/TLR4/CD14/MyD88 axis and the activation of NF-κB. Finally, OLC showed relevant anti-oxidant capability, assessed by abiotic assays, and reduced the intracellular amount of ROS generated by LPS exposure in THP-1 macrophages. Overall, these results suggest that the anti-oxidant activity and anti-inflammatory effect of OLC may cooperate in its protective effect against inflammatory stressors, thus being a possible alternative pharmacological strategy aimed at reducing the inflammatory process.

Effects Of Foliar Application Of Salicylic Acid And Calcium Chloride On Yield, Yeild Components And Some Physiological Parameters In Cotton

Salicylic acid (SA), a plant phenolic compound and calcium chloride have a great role on crop plants against biotic and abiotic stresses. This experiment was conducted to study the effects of foliar application of salicylic acid (S1=0, S2=50, S3=100 and S4=150 ppm) and calcium chloride (C1=0, C2=1.5 and C3=3 g/L) on cotton. The results showed that, salicylic acid increased the percentage of oil and nitrogen in seeds as well as the amount of chlorophyll content in the leaves, and this increased continued until S4=150ppm. Calcium chloride had no significant effect on them. The interaction between calcium chloride and salicylic acid had significant effect on the lint and grain yield in cotton and increased them. Biological yield, weight of seed per boll, weight of cotton per boll and number of boll per plant also affected by the interantion between of these two treatments. In thsese traits, although salicylic acid until S4 increased them, but the main effect of calcium chloride was up to C2. It was found unlike salicylic acid, which affectd on yield, yield components, photosynthesis piments and the content of mineral elements in seeds until S4, calcium chloride had a major effect on yield and yield components and this effect was until the level of C2.

Inhibitory effect of selected Indian honey on colon cancer cell growth by inducing apoptosis and targeting the β-catenin/Wnt pathway.

Colon cancer is the most prevalent cause of death from cancer across the globe. Although chemotherapy drugs are predominantly used, their toxicity always remains a cause of concern. As an alternative to synthetic drugs, natural compounds or nutraceuticals are comparatively less toxic. Honey is widely used across different cultures as an alternative form of medicine. It represents a prominent source of plant-phenolic compounds and there is demonstrable evidence of its anti-oxidant and anti-microbial activities. The aim of the present work was to investigate the anti-proliferative effect of some Indian honeys and analyze their mechanism of action in colon cancer. In order to establish the composition-activity relationship, we evaluated the bioactive components present in selected honey samples by GC-MS and HPLC analysis. Indian honey samples showed a significant inhibitory impact on cell growth by restricting cell proliferation, causing apoptosis, and restricting the cell cycle in the G2/M phase specifically for colon cancer cells. The apoptotic activities, as imparted by the honey samples, were established by Annexin V/PI staining, real-time PCR, and immunoblot analyses. The treated cells showed increased expressions of p53 and caspases 3, 8, and 9, thus indicating the involvement of both extrinsic and intrinsic apoptotic pathways. The honey samples were also found to inhibit the β-catenin/Wnt pathway. In the next phase of the study, the efficacy of these honey samples was evaluated in colon carcinoma induced SD-rats. Overall, these findings demonstrated that selected Indian honeys could be established as effective nutraceuticals for the prevention as well as cure of colon cancer.

Role of Phenolic Compounds in Human Disease: Current Knowledge and Future Prospects.

Inflammation is a natural protective mechanism that occurs when the body’s tissue homeostatic mechanisms are disrupted by biotic, physical, or chemical agents. The immune response generates pro-inflammatory mediators, but excessive output, such as chronic inflammation, contributes to many persistent diseases. Some phenolic compounds work in tandem with nonsteroidal anti-inflammatory drugs (NSAIDs) to inhibit pro-inflammatory mediators’ activity or gene expression, including cyclooxygenase (COX). Various phenolic compounds can also act on transcription factors, such as nuclear factor-κB (NF-κB) or nuclear factor-erythroid factor 2-related factor 2 (Nrf-2), to up-or downregulate elements within the antioxidant response pathways. Phenolic compounds can inhibit enzymes associated with the development of human diseases and have been used to treat various common human ailments, including hypertension, metabolic problems, incendiary infections, and neurodegenerative diseases. The inhibition of the angiotensin-converting enzyme (ACE) by phenolic compounds has been used to treat hypertension. The inhibition of carbohydrate hydrolyzing enzyme represents a type 2 diabetes mellitus therapy, and cholinesterase inhibition has been applied to treat Alzheimer’s disease (AD). Phenolic compounds have also demonstrated anti-inflammatory properties to treat skin diseases, rheumatoid arthritis, and inflammatory bowel disease. Plant extracts and phenolic compounds exert protective effects against oxidative stress and inflammation caused by airborne particulate matter, in addition to a range of anti-inflammatory, anticancer, anti-aging, antibacterial, and antiviral activities. Dietary polyphenols have been used to prevent and treat allergy-related diseases. The chemical and biological contributions of phenolic compounds to cardiovascular disease have also been described. This review summarizes the recent progress delineating the multifunctional roles of phenolic compounds, including their anti-inflammatory properties and the molecular pathways through which they exert anti-inflammatory effects on metabolic disorders. This study also discusses current issues and potential prospects for the therapeutic application of phenolic compounds to various human diseases.

Molecular Responses of Lactobacilli to Plant Phenolic Compounds: A Comparative Review of the Mechanisms Involved.

Lactobacilli are well-studied bacteria that can undergo oxidative selective pressures by plant phenolic compounds (PPCs) in plants, during some food fermentations or in the gastrointestinal tract of animals via dietary inputs. Lactobacilli are known to be more tolerant to PPCs than other bacterial groups and, therefore, must have mechanisms to cope with the effects of these metabolites. In this review, we intend to present what is currently known about the basics beyond the responses of Lactobacillus spp. to individual PPCs. We review the molecular mechanisms that are engaged in the PPC-modulated responses studied to date in these bacteria that have been mainly characterized by system-based strategies, and we discuss their differences and similarities. A wide variety of mechanisms are induced to increase the oxidative stress response highlighting the antimicrobial nature of PPCs. However other uncovered mechanisms that are involved in the response to these compounds are reviewed, including the capacity of PPCs to modulate the expression of molecular functions used by lactobacilli to adapt to host environments. This shows that these phytochemicals can act as more than just antimicrobial agents in the dual interaction with lactobacilli.

Polysaccharide-Based Active Coatings Incorporated with Bioactive Compounds for Reducing Postharvest Losses of Fresh Fruits

This review reports recently published research related to the application of polysaccharide-based biodegradable and edible coatings (BECs) fortified with bioactive compounds obtained from plant essential oils (EOs) and phenolic compounds of plant extracts. Combinations of polysaccharides such as starches, pectin, alginate, cellulose derivatives, and chitosan with active compounds obtained from clove, lemon, cinnamon, lavender, oregano, and peppermint have been documented as potential candidates for biologically active coating materials for retardation of quality changes in fresh fruits. Additionally, polysaccharide-based active coatings supplemented with plant extracts such as cashew leaves, pomegranate peel, red roselle, apple fiber, and green tea extracts rich in phenolic compounds and their derivatives have been reported to be excellent substituents to replace chemically formulated wax coatings. Moreover, EOs and plant polyphenolics including alcohols, aldehydes, ketones phenols, organic acids, terpenes, and esters contain hydroxyl functional groups that contribute bioactivity to BECs against oxidation and reduction of microbial load in fresh fruits. Therefore, BECs enriched with active compounds from EOs and plant extracts minimize physiological and microbial deterioration by reducing moisture loss, softening of flesh, ripening, and decay caused by pathogenic bacterial strains, mold, or yeast rots, respectively. As a result, shelf life of fresh fruits can be extended by employing active polysaccharide coatings supplemented with EOs and plant extracts prior to postharvest storage.

Effect of the natural polymethoxylated flavone artemetin on lipid oxidation and its impact on cancer cell viability and lipids

The biochemical class of the polymethoxylated flavonoids represents uncommon phenolic compounds in plants presenting a more marked lipophilic behavior due to the alkylation of its hydroxylic groups. As a polymethoxylated flavone, which concerns a different bioavailability, artemetin (ART) has been examined in vitro against lipid oxidation and its impact on cancer cells has been explored. Despite this flavone only exerted a slight protection against in vitro fatty acid and cholesterol oxidative degradation, ART significantly reduced viability and modulated lipid profile in cancer Hela cells at the dose range 10–50 μM after 72 h of incubation. It induced marked changes in the monounsaturated/saturated phospholipid class, significant decreased the levels of palmitic, oleic and palmitoleic acids, maybe involving an inhibitory effect on de novo lipogenesis and desaturation in cancer cells. Moreover, ART compromised normal mitochondrial function, inducing a noteworthy mitochondrial membrane polarization in cancer cells. A dose-dependent absorption of ART was evidenced in HeLa cell pellets (15.2% of the applied amount at 50 μM), coupled to a marked increase in membrane fluidity, as indicate by the dose-dependent fluorescent Nile Red staining (red emissions). Our results validate the ART role as modulatory agent on cancer cell physiology, especially impacting viability, lipid metabolism, cell fluidity, and mitochondrial potential.

A Systematic Review of the Cardiometabolic Benefits of Plant Products Containing Mixed Phenolics and Polyphenols in Postmenopausal Women: Insufficient Evidence for Recommendations to This Specific Population.

Menopause is characterized by endocrine and physiological changes and is often accompanied by increased body weight and cholesterol, glucose intolerance, and/or hypertension. These alterations are associated with increased risk for cardiovascular diseases (CVDs) and Type II diabetes mellitus (T2DM) that may be moderate by dietary plant phenolic compounds. In this review, we examine the current evidence of the impact of a variety of plant products (foods, extracts, beverages) rich in a mixture of phenolics and polyphenols on: (i) glucose and insulin levels; (ii) lipid profile; (iii) blood pressure; and (iv) biomarkers of inflammation and oxidative stress in postmenopausal women. We critically evaluate both the results of a range of intervention studies conducted in this specific subpopulation and the level of evidence supporting the benefits of consuming those products after the menopause. Overall, the current available evidence does not allow for specific dietary recommendations of these plant products rich in phenolics and polyphenols in this high-risk subpopulation. Our data show rather variable and small effects of the different products examined on the cardiometabolic biomarkers and further support the need to: (1) improve the quality of the study designs and data reporting; and (2) understand the variability in the response of the different biomarkers and establish clear differences between healthy and cardiometabolic disease levels.

Microplastics Reduce the Negative Effects of Litter-Derived Plant Secondary Metabolites on Nematodes in Soil

Microplastics and plant litter are ubiquitous in the soil environment, and both materials can influence soil properties and biota. Plant litter releases secondary metabolites (e.g., phenolic compounds) during the decomposition process, including chemical compounds active in plant defense. Effects of microplastics and plant litter on soil biota have been studied independently but we have limited information about the combined effects of both sources of chemicals. Here, we specifically focused on the interaction between plant litter and microplastics, as well as their potential effects on soil biota (i.e., nematodes). We used soils from a previous experiment that included three different types of microplastic fibers (MFs) and four different types of plant litter, which were incubated in the soil in all combinations of materials. After soil incubation (42 days) in the previous experiment, we here tested for effects on nematodes (Caenorhabditis elegans). Plant litter treatments negatively affected the reproduction of nematodes, but these effects were reduced when the soils were incubated along with MFs. We measured the phenolic concentrations in plant litter extracts in a kinetic experiment and found that phenolic concentrations significantly decreased with some of the MF additions. Our results suggest that microplastics can affect the potential effects of natural chemicals such as plant phenolic compounds. We urge future studies to consider this possibility as a key explanatory process underpinning effects of microplastic in the soil environment.

Microwave Assisted Extraction of Papaya Leaves and Investigation on Antioxidant Activity

Microwave assisted extraction (MAE) has gained lot of attention due to its advantages such as less solvent consumption, short time period, higher extraction efficiency, therefore serves as better alternative for conventional extraction methods of plant materials. Plant phenolic compounds are important constituents responsible for reducing the oxidative stress that induces tissue damage which is the one of the major causative factors associated with the chronic disease. Papaya plant is a medicinal plant which became popular for the treatment of dengue fever due to its property. Considering the current medicinal importance of the papaya plant, the present study was aimed at microwave assisted extraction of phenolic content from papaya leaf using ethanol, water as solvent and investigate their antioxidant potential.
 In order to compare the extraction efficiency of phenolic compounds, conventional extraction and microwave assisted extraction method was used to prepare the extracts. Then extracts were subjected to preliminary phytochemical analysis followed by the estimation of total phenolic content by using Folin-Ciocalteu method. Antioxidant activity was investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay.
 The alcoholic and aqueous extracts of papaya leaf showed the presence of steroids, alkaloids, saponins, carbohydrates, phenolic compounds by preliminary phytochemical analysis. FTIR spectrum of both aqueous and ethanolic extract showed characteristic peak at 3314.62 cm-1, 1635 cm-1 which provide evidence for presence of phenolic compounds. The total phenolic content of the alcoholic and aqueous leaf extracts from MAE was found to be 43.58mg and 80.58 mg/g papaya leaf powder of the Gallic acid equivalent (GAE), respectively. Aqueous solvent was found to be suitable for extraction of phenolic content from papaya leaf and Microwave assisted extracts showed higher phenolic content and therefore potential antioxidant activity. Therefore, papaya leaf is a good candidate to be used as a natural antioxidant for the treatment of various diseases.