Anti-Salmonella activity of constituents of Ardisia elliptica Thunb

Antibacterial activity against veterinary Salmonella was determined using dried fruit extracts of Ardisia elliptica Thunb. Chromatographic purification and spectroscopic structure studies provided three active anti-Salmonella compounds, namely, syringic acid, isorhamnetin and quercetin. The minimal inhibitory concentrations (MICs) of the isolated compounds ranged between 15.6 and 125.0 microg mL(-1).     

Phytochemical composition,in vitro antioxidant activity and antibacterial mechanisms of Neolamarckia cadamba fruits extracts

Aqueous extracts of Neolamarckia cadamba fruits prepared at different maturity stages were used for the analysis of various phytochemicals, and their antioxidant and antibacterial activities were determined. Ripe fruit extract had highest phenolics (3.14 mM GAE/ g fruit extract) with caffeic acid, tannic acid, syringic acid and quercetin as major phenolic compounds. The ripe fruit extract showed lowest IC₅₀ values in DPPH radical scavenging assay (231.33 μg fruit extract/ mL), and highest ABTS radical scavenging activity (111.18 μM TEAC/g). Immature fruit extract showed lowest minimum inhibitory concentration against tested bacteria, and the antibacterial activity was probably due to membrane permeation, as was evident by leakage of genetic material and reduction in propidium iodide uptake by bacterium; and by inhibition of sugar and amino acid uptake. The appreciable amount of phenolic compounds and biological activities in the aqueous extracts of N. cadamba fruits suggests it's potential application as natural preservative.     

Antioxidant activities of total phenols of Prunella vulgaris L. in vitro and in tumor-bearing mice

Prunella vulgaris L. (PV, Labiatae) is known as a self-heal herb. The different extracts of dried spikes were studied for the best antioxidant active compounds. The 60% ethanol extract (P-60) showed strong antioxidant activity based on the results of 2,2'-azino-di(3-ethylbenzthiazoline-6-sulfonic acid (ABTS˙+), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assay methods. High performance liquid chromatography (HPLC) and LC/MS analysis showed that the main active compounds in P-60 were phenols, such as caffeic acid, rosmarinic acid, rutin and quercetin. Total phenols were highly correlated with the antioxidant activity (R2=0.9988 in ABTS˙+; 0.6284 in DPPH and 0.9673 FRAP tests). P-60 could inhibit significantly the tumor growth in C57BL/6 mice. It can also been showed that increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) content in serum of tumor-bearing mice. These results suggested that P-60 extract had high antioxidant activity in vitro and in vivo and total phenols played an important role in antioxidant activity for inhibition of tumor growth.     

Phytochemical investigation and hepatoprotective activity of Cupressus sempervirens L. leaves growing in Egypt

Three phenolic compounds cosmosiin, caffeic acid, and p-coumaric acid were isolated for the first time from the leaves of Cupressus sempervirens L., together with cupressuflavone, amentoflavone, rutin, quercitrin, quercetin, myricitrin. The isolated compounds were identified using (1)H- and (13)C-NMR spectra. The hepatoprotective activity of the MeOH extract was carried out in liver homogenate of normal and CCl(4)-treated rats; a significant decrease in glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, cholesterol level, and triglycerides, while a significant increase in the total protein level, was observed after the oral administration of MeOH extract. The free radical scavenging activity against stable 2,2-diphenyl-2-picrylhydrazyl (DPPH*) was measured for MeOH extract and some of the isolated phenolic compounds in comparison with alpha-tocopherol and butylated hydroxy toluene as standard antioxidants using ESR technique, showed high antioxidant activity for quercetin, rutin, caffeic acid, and p-coumaric acid.     

Documentation of bioactive principles of the exudate gel (EG) from the stem of Caralluma retrospiciens (Ehrenb) and in vitro antibacterial activity – Part A

Caralluma retrospiciens (Ehrenb) is a desert plant widely distributed in the hilly semi-desert regions of southern part of Saudi Arabia. The exudate gel (EG) from the stem of plant is occasionally used for wound healing by the people of the southern part of Saudi Arabia. This study investigated the phytochemical composition, FT-IR, GC–MS spectral analysis and in vitro antibacterial activity of the EG from the stem of C. retrospiciens (Ehrenb). The plant C. retrospiciens (Ehrenb.) was collected from the hills of Rijal Almaa, a heritage village of Saudi Arabia. The EG was isolated from the stem of C. retrospiciens (Ehrenb.). Physical parameters such as viscosity and zeta potential (ZP) were determined. Phytochemical analysis, FT-IR and GC–MS spectroscopy analysis were performed to determine the bio active constituents. The antibacterial activity of the isolated gel was performed by in vitro agar well diffusion technique. The study demonstrated that the viscosity and ZP of EG influenced the efficacy of antibacterial spectral properties. The FT-IR spectroscopy of the EG showed various functional groups at 3278.29, 2951.16, 2840.44, 2527.55, 2161.67, 1647.40, 1450.06, 1406.7, 1286, 1108.34, 5536.63 cm⁻¹. Various pharmaceutically important chemical compounds were identified using GC–MS analysis. The bioactive compounds are “Sorbic Acid”, “Rhodopsin”, “1-Heptatriacotanol”, “Oxiraneundecanoic acid, 3-pentyl-, methyl ester, trans”, “Cholestan-3-ol, 2-methylene-, (3á,5à)”, “Benzoic acid”, “3-pentyl-, methyl ester trans”, “Hexanoic acid, 2-ethyl-, oxybis (2,1-ethanediyloxy-2,1-ethanediyl) ester”, etc. The antibacterial effect of the EG showed a wide spectrum of activity against the screened human pathogenic bacteria. The results demonstrate the bioactive principles of EG from C. retrospiciens (Ehrenb.) exerts the antibacterial properties in vitro.     

Comparison of the contents of various antioxidants of sea buckthorn berries using CE

The increased interest in sea buckthorn (Hippophae rhamnoides L.) made it possible to investigate the antioxidant content in it. To address this issue, the presence of following antioxidant compounds were analyzed: trans-resveratrol, catechin, myricetin, quercetin, p-coumaric acid, caffeic acid, L-ascorbic acid (AA), and gallic acid (linear range of 50-150 micromol/L) in six different varieties of sea buckthorn berries extracts (sea buckthorn varieties: "Trofimovskaja (TR)," "Podarok Sadu (PS)," and "Avgustinka (AV),") received from two local Estonian companies. Trans-Resveratrol, catechin, AA, myricetin, and quercetin were found in extracts of sea buckthorn. Moreover, AA, myricetin, and quercetin contents were quantified. The biggest average AA content was found in TR (740 mg/100 g of dried berries, respectively). Furthermore, the same varieties gave the biggest quercetin content 116 mg/100 g of dried berries, respectively. For analysis, CZE was used and the results were partly validated by HPLC. Statistically no big differences in levels of antioxidants were consistently found in different varieties of sea buckthorn extracts investigated in this work.     

Ethylene Induction of Non-Enzymatic Metabolic Antioxidants in Matricaria chamomilla

Phytochemical investigations of Matricaria chamomilla L. (Asteraceae) stated the presence of several compounds with an established therapeutic and antioxidant potential. The chamomile non-enzymatic antioxidant system includes low molecular mass compounds, mainly polyphenols such as cinnamic, hydroxybenzoic and chlorogenic acids, flavonoids and coumarins. The objective of this work was to evaluate the role of the non-enzymatic antioxidant system after stimulation by ethylene in tetraploid chamomile plants. Seven days of ethylene treatment significantly increased the activity of phenylalanine ammonia-lyase, which influenced the biosynthesis of protective polyphenols in the first step of their biosynthetic pathway. Subsequently, considerable enhanced levels of phenolic metabolites with a substantial antioxidant effect (syringic, vanillic and caffeic acid, 1,5-dicaffeoylquinic acid, quercetin, luteolin, daphnin, and herniarin) were determined by HPLC-DAD-MS. The minimal information on the chlorogenic acids function in chamomile led to the isolation and identification of 5-O-feruloylquinic acid. It is accumulated during normal conditions, but after the excessive effect of abiotic stress, its level significantly decreases and levels of other caffeoylquinic acids enhance. Our results suggest that ethephon may act as a stimulant of the production of pharmaceutically important non-enzymatic antioxidants in chamomile leaves and thus, lead to an overall change in phytochemical content and therapeutic effects of chamomile plants, as well.     

Nettle (Urtica dioica L.) as a source of antioxidant and anti-aging phytochemicals for cosmetic applications

Nettle (Urtica dioica L.) is a herbaceous perennial that has been used for centuries in folk medicine. More recently, nettle extracts have also been used in cosmetics because of the many benefits of their topical application for skin health. Their potential anti-aging action is of particular interest and is primarily ascribed to their antioxidant capacity. Here, using an experimental design approach and a clustering analysis, we linked the phytochemical composition of nettle extracts to their biological activities. This approach confirmed the antioxidant capacity of nettle extracts as well as providing the first evidence of another mechanism for their anti-aging potential involving the inhibition of enzyme activities, such as elastase and collagenase. We attributed these inhibitory effects to ursolic acid and quercetin present in the nettle extracts. Our results also demonstrated the possibility of extracting ursolic acid, quercetin and other phenolic compounds differentially to obtain an extract with a strong antioxidant capacity and anti-aging activities toward both elastase and collagenase. This could be of particular interest for cosmetic applications of nettle extracts.     

UHPLC-MS/MS phenolic profiling and in vitro antioxidant activities of Inula graveolens (L.) Desf

Inula graveolens (L.) Desf. is an annual aromatic herb which has various uses on alternative medicine in many region of the world. In this study, antioxidant activities of ethanol and water extracts of the plant leaves were determined by in vitro DPPH method and phenolic composition of the plant sample was determined by LC-MS/MS analysis. The results showed that chlorogenic acid, quinic acid, hyperoside, protocatechuic acid and quercetin were the major phenolic compounds among the 27 standard compounds. The significant antioxidant capacity of the plant might be related with the high abundance of phenolic compounds.     

Antioxidant activities and phenolics profiling of different parts of Carica papaya by LCMS-MS

This article deals with the comparison of the antioxidant activity of aqueous extracts of various parts of Carica papaya L. The evaluation of total phenolic content and total flavonoid content revealed high antioxidant potential of the seeds and fruits. The free radical-scavenging potential of the aqueous extracts indicated the seeds to have better DPPH-scavenging activity than fruits. The results were augmented by the FRAP activity as well. The phenolics present in the extracts were separated and identified as 5-hydroxy feruloyl quinic acid, acetyl p-coumaryl quinic acid, quercetin-3-O-rhamnoside, syringic acid hexoside, 5-hydroxy caffeic quinic acid, peonidin-3-O-glucoside, sinapic acid-O-hexoside, cyaniding-3-O-glucose and methyl feruloyl glycoside by LCMS-MS technique.     

Chemometric Optimization of Biologically Active Compounds Extraction from Grape Marc: Composition and Antimicrobial Activity

The article focuses on the optimization of the extraction process of biologically active compounds (BAC) from grape marc—a by-product of the wine industry. The influence of temperature, specifically 30 °C, 45 °C and 65 °C, and ethanol concentration in solutions, specifically 0–96% (v/v) on the extraction yield of polyphenols, flavonoids, tannins and anthocyanins, were investigated. The composition of individual polyphenols, anthocyanins and organic acids, antioxidant activity (DPPH and ABTS) and CIELab chromatic characteristics of the grape marc extracts (GME), were characterized. The microbiostatic and microbicidal effects in direct contact of GME with pathogenic microorganisms, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, were determined in vitro. The influence of extraction parameters on the total polyphenol content (TPC), total flavonoid content (TFC), tannin content (TC), total anthocyanin content (TAC) and their interdependencies were studied using information analysis. A mathematical model was developed on cubic spline functions. The analysis of individual compounds showed the presence of a wide range of flavonoids (procyanidin B2, procyanidin B1, hyperoside and quercetin), flavones (catechin), hydroxybenzoic acid derivatives (gallic, protocatechuic, p-hydroxybenzoic acids, m-hydroxybenzoic acid, syringic acid), hydroxycinic acid derivatives and ferulic acid methyl ester. The malvidol-3-glucoside was the main anthocyanin identified in the extract. A high amount of tartaric acid was also found. GME showed significant antimicrobial activity against Gram-positive bacteria and lower activity against Gram-negative bacteria.     

Polyphenol contents and antioxidant activity of Brassica nigra (L.) Koch. leaf extract

Profound research has been done on the medicinal value of Brassica nigra (BN) seeds, and the leaves of the plant have been investigated in this study. The methanol extracts of the leaves were subjected to several in?vitro studies. The antioxidant activity of methanol extract was demonstrated with a wide range of concentration, 10-500?μg?mL(-1), and the antioxidant activity increased with the increase in concentration. Total phenol content was found to be 171.73?±?5.043 gallic acid equivalents and the total flavonoid content 7.45?±?0.0945 quercetin equivalents. Further quantification and identification of the compounds were done by HPTLC and GC-MS analyses. The predominant phenolic compounds determined by HPTLC were gallic acid, followed by quercetin, ferulic acid, caffeic acid and rutin. The free radical quenching property of BN leaf extract suggests the presence of bioactive natural compounds.     

Chemical fingerprint analysis of phenolics of Albizia chinensis based on ultra-performance LC-electrospray ionization-quadrupole time-of-flight mass spectrometry and antioxidant activity

Albizia species have been shown to have anti-inflammatory and anti-allergic properties. However, efficient analytical methods for identification of their active constituents are still lacking. Ultra-performance liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) was used to study the phenolic composition of the ethanolic extracts of different parts (flowers, leaves, pods and bark) of A. chinensis. In addition, the antioxidant activity of the ethanolic extracts was evaluated by the 1,1-diphenyl-2-picryl hydrazyl (DPPH) free-radical and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical cation scavenging methods. Four compounds were isolated from the ethanolic extract of the flowers and characterized by 1H and 13C NMR spectroscopy as quercetin-3-O-rhamnoside, quercetin, quercetin-3-O-arabinofuranoside, and myricetin-3-O-rhamnoside. Separation and quantification of the phenolics was accomplished using a reversed-phase BEH C18 column with the mobile phase of methanol-water (0.05% formic acid), and detection wavelengths of 360 and 254 nm.     

Activity-Guided Characterization of COX-2 Inhibitory Compounds in Waltheria indica L. Extracts

Inflammation is the body’s response to infection or tissue injury in order to restore and maintain homeostasis. Prostaglandin E2 (PGE-2) derived from arachidonic acid (AA), via up-regulation of cyclooxygenase-2 (COX-2), is a key mediator of inflammation and can also be induced by several other factors including stress, chromosomal aberration, or environmental factors. Targeting prostaglandin production by inhibiting COX-2 is hence relevant for the successful resolution of inflammation. Waltheria indica L. is a traditional medicinal plant whose extracts have demonstrated COX-2 inhibitory properties. However, the compounds responsible for the activity remained unknown. For the preparation of extracts with effective anti-inflammatory properties, characterization of these substances is vital. In this work, we aimed to address this issue by characterizing the substances responsible for the COX-2 inhibitory activity in the extracts and generating prediction models to quantify the COX-2 inhibitory activity without biological testing. For this purpose, an extract was separated into fractions by means of centrifugal partition chromatography (CPC). The inhibitory potential of the fractions and extracts against the COX-2 enzyme was determined using a fluorometric COX-2 inhibition assay. The characterizations of compounds in the fractions with the highest COX-2 inhibitory activity were conducted by high resolution mass spectrometry (HPLC-MS/MS). It was found that these fractions contain alpha-linolenic acid, linoleic acid and oleic acid, identified and reported for the first time in Waltheria indica leaf extracts. After analyzing their contents in different Waltheria indica extracts, it could be demonstrated that these fatty acids are responsible for up to 41% of the COX-2 inhibition observed with Waltheria indica extract. Additional quantification of secondary metabolites in the extract fractions revealed that substances from the group of steroidal saponins and triterpenoid saponins also contribute to the COX-2 inhibitory activity. Based on the content of compounds contributing to COX-2 inhibition, two mathematical models were successfully developed, both of which had a root mean square error (RMSE) = 1.6% COX-2 inhibitory activity, demonstrating a high correspondence between predicted versus observed values. The results of the predictive models further suggested that the compounds contribute to COX-2 inhibition in the order linoleic acid > alpha linolenic acid > steroidal saponins > triterpenoid saponins. The characterization of substances contributing to COX-2 inhibition in this study enables a more targeted development of extraction processes to obtain Waltheria indica extracts with superior anti-inflammatory properties.     

Study on the phenolic constituents of the flowers and leaves of Trifolium repens L

The flowers and leaves of Trifolium repens L. (Fabaceae) were subjected to phytochemical investigation in order to identify their major chemical constituents and to evaluate in?vitro antioxidant activity of the isolated compounds against DPPH˙. A total of 12 flavonoids, pterocarpan and methyl caffeate were isolated, then characterised by UV, MS, NMR spectroscopy and identified as quercetin and kaempferol 3-O-(6″-α-rhamnopyranosyl-2″-β-xylopyranosyl)-β-galactopyranosides (1, 2), kaempferol 3-O-(2″,6″-α-dirhamnopyranosyl)-β-galactopyranoside, mauritianin (3), quercetin and kaempferol 3-O-(2″-β-xylopyranosyl)-β-galactopyranosides (4, 5), kaempferol and quercetin 3-O-β-(6″-O-acetyl)-galactopyranosides (6, 7), trifolin (8), hyperoside (9), myricetin 3-O-β-galactopyranoside (10), quercetin (11), ononin (12), medicarpin 3-O-β-glucopyranoside (13) and methyl caffeate (14). Mauritianin, ononin, pterocarpan and methyl caffeate have been reported in this plant for the first time. The compounds 4, 7, 9, 10, and 11 were tested for their antioxidant effect against DPPH˙. All studied compounds were found to have potent activity, but the most effective in the test were compounds 9, 10 and 11 (EC(50) values in the range 7.51-9.52?μM).     

Determination of Phenolic Compounds and the Antioxidant Capacity of Ximenia parviflora Benth. var. parviflora (Olacaceae) Fruit by High-Performance Liquid Chromatography with Diode Array Detection

The total phenolic and flavonoid content, phenolic composition, and in vitro antioxidant capacity of ethanolic extracts of Ximenia parviflora Benth. var. parviflora fruits collected at Zinaparo, Michoacan (in central Mexico) were determined. Fruit extracts present a high scavenging activity of 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis[3-ethylbenzothiazoline-6-sulfonic acid] radicals (71.49?±?0.11% and 85.00?±?1.29% inhibition, respectively). The four phenolic compounds identified in fruit extracts by high-performance liquid chromatography with diode array detection were gallic acid, chlorogenic acid, caffeic acid, and quercetin. X. parviflora fruits may be used as a starting material for the extraction of high value antioxidant phenolic compounds with potential applications in the pharmaceutical and dietary supplement industries.     

Antioxidative phenols and phenolic glycosides from Curculigo orchioides

A new orcinol glucoside, orcinol-1-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (3), was isolated from the rhizomes of Curculigo orchioides GAERTN., together with seven known compounds: orcinol glucoside (1), orcinol-1-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (2), curculigoside (4), curculigoside B (5), curculigoside C (6), 2,6-dimethoxyl benzoic acid (7), and syringic acid (8). The structures of these compounds were elucidated using spectroscopic methods. The antioxidant activities of these isolated compounds were evaluated by colorimetric methods based on their scavenging effects on hydroxyl radicals and superoxide anion radicals, respectively. All the compounds showed potent antioxidative activities and the structure-activity relationship is discussed.     

Multifunctional approaches to provide potential pharmacophores for the pharmacy shelf: Heracleum sphondylium L. subsp. ternatum (Velen.) Brummitt.

Heracleum sphondylium L. subsp. ternatum (Velen.) Brummitt. commonly known as “hogweed” is traditionally used to manage several human ailments. This investigation assessed, for the first time, the enzyme inhibitory properties, antioxidant activity, phytochemical profile, antimutagenic, and antimicrobial potential of the ethyl acetate, methanol, and water extracts of H. sphondylium. We also established the possible interactions of identified phenolic compounds with cholinesterases, amylase, glucosidase, and tyrosinase using in silico docking studies. Chlorogenic acid was found in high amounts in the methanol extract of H. sphondylium. The methanol extract was an effective inhibitor of acetylcholinesterase (1.70 mg galantamine equivalent (GALAE)/g extract) while the ethyl acetate extract showed pronounced inhibitory action against butyrylcholinesterase (1.77 mg GALAE/g extract). The extracts exhibited low inhibition against amylase (0.12-0.84 mmol acarbose equivalent (ACAE)/g extract) and a more pronounced inhibition against glucosidase (2.29–3.65 mmol ACAE/g extract). In silico results showed that rutin and quercetin (-70.4 and -72.2 Kcal/mol, for rutin and quercetin respectively) docked to the enzymatic cavity of acetylcholinesterase but these phenolic compounds showed less affinity with butyrylcholinesterase (-15.0 and -5.2 Kcal/mol, for rutin and quercetin respectively). The extracts did not induce any mutations on the bacterial strains, while they have excellent antimutagenic capacity against well-known mutagens (inhibition values 98%, 97% and 96%). The methanol extract (0.78 mg/ml) showed moderate antifungal activity while the ethyl acetate extract (0.78–3.12 mg/ml) showed weak to moderate antimicrobial activity. This study provides valuable baseline data which might serve for the development of future pharmacophores for the management of human ailments.     

Identification and in vitro antioxidant activities of phenolic compounds isolated from Cynoglossum cheirifolium L.

In an extensive search for bioactive compounds from plant sources, the quantitative and qualitative characterisation of the compounds present in Cynoglossum cheirifolium extracts was studied. Total phenolic and flavonoid contents were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined through DPPH^? scavenging activity and Ferric reducing antioxidant power (FRAP). Our study showed that leaves produce more phenolic compounds, followed by flowering aerial part. The butanolic fraction obtained from leaves extract exhibited the highest total phenolics (78.65 ± 3.58 mg GAE/g DW) and flavonoids (22.15 ± 4.66 mg CE/g DW). In contrast, this fraction displayed the highest DPPH^? scavenging ability with IC₅₀ values of 0.06 ± 0.003 mg/mL. The RP-HPLC-PDA analysis of phenolic compounds from leaves of C. cheirifolium lets to identify: rosmarinic acid, ferulic acid, caffeic acid, p-coumaric acid, syringic acid, sinapic acid and rutin. The obtained results indicate that this plant represent a valuable source of natural antioxidants.     

Using natural deep eutectic solvents for the extraction of metabolites in Byrsonima intermedia leaves

Natural deep eutectic solvents have been used as an alternative to organic solvents for the extraction of plants metabolites, allowing for the extraction of compounds of different polarities, while being inexpensive, non‐toxic, and easy to prepare. This work presents the comparison of the chromatographic profiles by high‐performance liquid chromatography with diode‐array detection obtained from Byrsonima intermedia (Malpighiaceae) using five choline chloride‐based natural deep eutectic solvents, in addition to the most used traditional extraction solvents, methanol/water 7:3 and ethanol/water 7:3 v/v. A reference extract was used to tentatively identify compounds by high‐performance liquid chromatography with tandem mass spectrometry. The water content appeared to be important for the extraction efficiency and the mixture choline chloride/glycerol was shown to be the best candidate for efficiently extracting this matrix when compared with the traditional extraction media in addition to being far greener as shown by the environmental analysis tool. Seven phenolic compounds (digalloyl quinic acid, proanthocyanidin dimer, galloylproanthocyanidin dimer, quercetin‐O‐hexoside, galloyl quercetin hexoside, quercetin‐O‐pentoside, and galloyl quercetin pentoside) were tentatively identified in all extracts. Moreover, the influence of these solvents on the antioxidant activity of the extracts was studied and the results for choline chloride/glycerol extracts were very similar to that of the traditional extraction solvents.