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.     

Nutraceutical Potential of Leaf Hydro-Ethanolic Extract of the Edible Halophyte Crithmum maritimum L.

Aromatic halophytes represent an exceptional source of natural bioactive compounds for the food industry. Crithmum maritimum L., also known as sea fennel, is a halophyte plant colonizing cliffs and coastal dunes along Mediterranean and Atlantic coasts. It is well known to produce essential oils and polyphenols endowed with antioxidant and biological effects. The present work reports the phytochemical profile, as well as antioxidant, antimicrobial and antimutagenic properties of C. maritimum leaf hydro-alcoholic extract. From LC-ESI-MS analysis, eighteen phenolic compounds were depicted in sea fennel extract and the amount of total phenolic content exceeds 3% DW. Accordingly, C. maritimum extract showed strong antioxidant activities, as evidenced by in vitro (DPPH, ORAC, FRAP) and ex vivo (CAA-RBC and hemolysis) assays. An important antimicrobial activity against pathogenic strains was found as well as a strong capacity to inhibit Staphylococcus aureus (ATCC 35556) biofilm formation. Sea fennel extracts showed a significant decrease of mutagenesis induced by hydrogen peroxide (H₂O₂) and menadione (ME) in Saccharomyces cerevisiae D7 strain. In conclusion, our results show that C. maritimum is an exceptional source of bioactive components and exert beneficial effects against oxidative or mutagenic mechanisms, and pathogenic bacteria, making it a potential functional food.     

Antimicrobial and Antioxidant Properties of Total Polyphenols of Anchusa italica Retz

Anchusa italica Retz has been used for a long time in phytotherapy. The aim of the present study was to determine the antioxidant and antibacterial activities of extracts from the leaves and roots of Anchusa italica Retz. We first determined the content of phenolic compounds and flavonoids using Folin–Ciocalteu reagents and aluminum chloride (AlCl₃). The antioxidant activity was determined using three methods: reducing power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC). The antimicrobial activity was investigated against four strains of Escherichia coli, two strains of Klebsiella pneumoniae and coagulase-negative Staphylococcus, and one fungal strain of Candida albicans. The results showed that the root extract was rich in polyphenols (43.29 mg GAE/g extract), while the leave extract was rich in flavonoids (28.88 mg QE/g extract). The FRAP assay showed a strong iron reduction capacity for the root extract (IC₅₀ of 0.11 µg/mL) in comparison to ascorbic acid (IC₅₀ of 0.121 µg/mL). The DPPH test determined an IC₅₀ of 0.11 µg/mL for the root extract and an IC₅₀ of 0.14 µg/mL for the leaf extract. These values are low compared to those for ascorbic acid (IC₅₀ of 0.16 µg/mL) and BHT (IC₅₀ 0.20 µg/mL). The TAC values of the leaf and root extracts were 0.51 and 0.98 mg AAE/g extract, respectively. In vitro, the extract showed inhibitory activity against all strains studied, with diameters of zones of inhibition in the range of 11.00–16.00 mm for the root extract and 11.67–14.33 mm for the leaf extract. The minimum inhibitory concentration was recorded for the leaf extract against E. coli (ATB:57), corresponding to 5 mg/mL. Overall, this research indicates that the extracts of Anchusa italica Retz roots and leaves exert significant antioxidant and antibacterial activities, probably because of the high content of flavonoids and polyphenols.     

Phenolic compounds,essential oil composition,and antioxidant activity of Angelica purpurascens (Avé-Lall.) Gill

In this study, methanol extracts (MEs) and essential oil (EO) of Angelica purpurascens (Avé-Lall.) Gill obtained from different parts (root, stem, leaf, and seed) were evaluated in terms of antioxidant activity, total phenolics, compositions of phenolic compound, and essential oil with the methods of 2,2-azino-bis(3ethylbenzo-thiazoline-6-sulfonic acid (ABTS•⁺), 2,2-diphenyl-1-picrylhydrazil (DPPH•) radical scavenging activities, and ferric reducing/antioxidant power (FRAP), the Folin–Ciocalteu, liquid chromatography−tandem mass spectrometry (LC−MS/MS), and gas chromatography-mass spectrometry (GC−MS), respectively. The root extract of A. purpurascens exhibited the highest ABTS•⁺, DPPH•, and FRAP activities (IC₅₀: 0.05 ± 0.0001 mg/mL, IC₅₀: 0.06 ± 0.002 mg/mL, 821.04 ± 15.96 µM TEAC (Trolox equivalent antioxidant capacity), respectively). Moreover, EO of A. purpurascens root displayed DPPH• scavenging activity (IC₅₀: 2.95 ± 0.084 mg/mL). The root extract had the highest total phenolic content (438.75 ± 16.39 GAE (gallic acid equivalent), µg/mL)). Twenty compounds were identified by LC−MS/MS. The most abundant phenolics were ferulic acid (244.39 ± 15.64 μg/g extract), benzoic acid (138.18 ± 8.84 μg/g extract), oleuropein (78.04 ± 4.99 μg/g extract), and rutin (31.21 ± 2.00 μg/g extract) in seed, stem, root, and leaf extracts, respectively. According to the GC−MS analysis, the major components were determined as α-bisabolol (22.93%), cubebol (14.39%), α-pinene (11.63%), and α-limonene (9.41%) among 29 compounds. Consequently, the MEs and EO of A. purpurascens can be used as a natural antioxidant source.     

Molecular Distillation of Lavender Supercritical Extracts: Physicochemical and Antimicrobial Characterization of Feedstocks and Assessment of Distillates Enriched with Oxygenated Fragrance Components

Lavandula angustifolia is one of the most widely cultivated non-food crops used in the production of essential oil; it is used in perfumery, aromatherapy, pharmaceutical preparations, and food ingredients. In this study, supercritical fluid extraction (SFE) and molecular distillation (MD) were combined, primarily to enrich scCO₂ extracts with lavender oxygenated monoterpenes, avoiding thermal degradation, hydrolysis, and solvent contamination, and maintaining the natural characteristics of the obtained oils. Molecular distillation was developed for the first time for the extraction of crucial lavender fragrance ingredients, i.e., from two scCO₂ extracts obtained from dry flower stems of lavender cultivated in Poland and Bulgaria. The best results for high-quality distillates were obtained at 85 °C (EVT) and confirmed that linalyl acetate content increased from 51.54 mg/g (initial Bulgarian lavender extract, L-Bg-E) and 89.53 mg/g (initial Polish lavender extract, L-Pl-E) to 118.41 and 185.42 mg/g, respectively, corresponding to increases of 2.3 and 2.1 times in both distillate streams, respectively. The distillates, light oils, and extracts from lavender were also evaluated for their antimicrobial properties by determining the minimum inhibitory concentration (MIC) by the broth microdilution method. Generally, Gram-positive bacteria and Candida spp. were more sensitive to all distilled fractions and extracts than Escherichia coli (Gram-negative bacteria).     

Lipase from Carica papaya latex presents high enantioselectivity toward the resolution of prodrug (R,S)-2-bromophenylacetic acid octyl ester

Besides the well-known papain, lipolytic activity is another interesting enzymatic activity present in latex from Carica papaya. This lipolytic activity is strongly attached to the latex solid phase, resulting in a naturally immobilized biocatalyst. In this work we describe the kinetic resolution of (R,S)-2-bromophenylacetic acid octyl ester by Carica papaya crude latex and two partially purified latex fractions. Several parameters, such as substrate concentration and solvent effects were studied. The best results were obtained using decane as solvent with 50 mM of substrate and 50 mg/mL enzyme/reaction medium; under these conditions, a high enantioselectivity (E >200) was obtained with crude latex. A twofold increase of the initial rate maintaining E >200 was obtained using purified fractions without protease and without esterase. Lipase from Carica papaya latex is the most enantioselective wild-type enzyme ever described for the studied reaction.     

Antioxidant and Anticholinesterase Activities of Extracts and Phytochemicals of Syzygium antisepticum Leaves

Bioassay-guided separation of young leaves extracts of Syzygium antisepticum (Blume) Merr. & L.M. Perry led to the isolation of four triterpenoids (betulinic acid, ursolic acid, jacoumaric acid, corosolic acid) and one sterol glucoside (daucosterol) from the ethyl acetate extract, and three polyphenols (gallic acid, myricitrin, and quercitrin) from the methanol (MeOH) extract. The MeOH extract of S. antisepticum and some isolated compounds, ursolic acid and gallic acid potentially exhibited acetylcholinesterase activity evaluated by Ellman’s method. The MeOH extract and its isolated compounds, gallic acid, myricitrin, and quercitrin, also strongly elicited DPPH radical scavenging activity. In HEK-293 cells, the MeOH extract possessed cellular antioxidant effects by attenuating hydrogen peroxide (H₂O₂)-induced ROS production and increasing catalase, glutathione peroxidase-1 (GPx-1), and glutathione reductase (GRe). Furthermore, myricitrin and quercitrin also suppressed ROS production induced by H₂O₂ and induced GPx-1 and catalase production in HEK-293 cells. These results indicated that the young leaves of S. antisepticum are the potential sources of antioxidant and anticholinesterase agents. Consequently, S. antisepticum leaves are one of indigenous vegetables which advantage to promote the health and prevent diseases related to oxidative stress.     

Effect of Extraction Solvent and Temperature on Polyphenol Profiles,Antioxidant and Anti-Inflammatory Effects of Red Grape Skin By-Product

A fully-detailed LC-MS qualitative profiling of red grape skin, extracted with a mixture of ethanol and water (70:30 v:v) has permitted the identification of 65 compounds which can be classified into the following chemical classes: organic and phenolic acids (14 compounds), stilbenoids (1 compound), flavanols (21 compounds), flavonols (15 compounds) and anthocyanins (14 compounds). The extraction yield obtained with water at different temperatures (100 °C, 70 °C, room temperature) was then evaluated and the overall polyphenol content indicates that EtOH:H₂O solvent is the most efficient and selective for polyphenol extraction. However, by analyzing the recovery yield of each single polyphenol, we found that water extraction under heating conditions is effective (extraction yield similar or even better in respect to the binary solvent) for some polyphenolic classes, such as hydrophilic procyanidins, phenolic acids, flavonol glucosides and stilbenoids. However, according to their lipophilic character, a poor yield was found for the most lipophilic components, such as flavonol aglycones, and in general for anthocyanins. The radical scavenging activity was in accordance with the polyphenol content, and hence, much higher for the extract obtained with the binary solvent in respect to water extraction. All the tested extracts were found to have an anti-inflammatory activity in the R3/1 cell line with NF-kb reporter challenged with 0.01 µg/mL of IL-1α, in a 1 to 250 µg/mL concentration range. An intriguing result was that the EtOH:H₂O extract was found to be superimposable with that obtained using water at 100 °C despite the lower polyphenol content. Taken together, the results show the bioactive potentialities of grape skin extracts and the possibility to exploit this rich industrial waste. Water extraction carried out by heating is an easy, low-cost and environmentally friendly extraction method for some polyphenol classes and may have great potential for extracts with anti-inflammatory activities.     

The Future of Carica papaya Leaf Extract as an Herbal Medicine Product

Carica papaya (papaya) leaf extract has been used for a long time in a traditional medicine to treat fever in some infectious diseases such as dengue, malaria, and chikungunya. The development of science and technology has subsequently made it possible to provide evidence that this plant is not only beneficial as an informal medication, but also that it has scientifically proven pharmacological and toxicological activities, which have led to its formal usage in professional health care systems. The development of formulations for use in nutraceuticals and cosmeceuticals has caused this product to be more valuable nowadays. The use of good manufacturing practice (GMP) standards, along with the ease of registering this product facilitated by policies of the national government, will absolutely increase the value of papaya leaf extract as a vital nutraceutical and cosmeceutical products in the near future. In this article, we review the potential of papaya leaf extract to be a high-value commodity in terms of its health effects as well as its industrial benefits.     

Chemoenzymatic synthesis of (5S)- and (5R)-hydroxymethyl-3,5-dimethyl-4-(methoxymethoxy)-5H-thiophen-2-one: a precursor of thiolactomycin and determination of its absolute configuration

A convenient enantioselective synthesis of (5S)- and (5R)-hydroxymethyl-3,5-dimethyl-4-(methoxymethoxy)-5H-thiophen-2-one, a key intermediate in the synthesis of thiolactomycin has been carried out by a Carica papaya lipase-mediated resolution protocol to provide (R)-2 in a 94% ee and its enantiomer (S)-9 in a 98% ee. The absolute configuration at the C-5 position has been determined by Mosher’s method.     

Anti-fertility effects of fractions from Carica papaya (Pawpaw) Linn. methanol root extract in male Wistar rats

The methanol root extracts of Carica papaya (Pawpaw) are used in eastern Nigeria for the treatment of malaria, hepatitis and jaundice. The aim of this study was to investigate the effects of the fractions isolated from C. papaya methanol root extract on fertility in male Wistar rats using sperm counts, percentage defective sperm cells (morphology), biochemical and hormonal assays as biomarkers. The roots of C. papaya were extracted using 80% methanol for 72 h. Oral acute toxicity study was done with the crude extract for 24 h. The extract was fractionated by column chromatography using petroleum ether, chloroform, ethyl acetate and methanol. The petroleum ether fraction was further fractionated on preparative TLC using ethyl acetate–methanol solvent systems to isolate CPFE 1, CPFE 2 and CPFM 1. The 3 fractions (75 mg/kg) were used to treat male Wistar rats orally for 60 days. Animals were euthanized and testes collected, homogenized and used for sperm count and motility. Plasma and serum were used to assay biochemical parameters including aspartate aminotransferase (AST), blood urea nitrogen (BUN), total bilirubin (TB), alkaline phosphatase (ALP), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT), triglycerides, hormones (LH and FSH). Histopathological study of the testes, kidney, heart and liver were conducted. Acute toxicity result showed that C. papaya root extract produced no mortalities at the dose of 2000 mg/kg but induced CNS-related symptoms as well as diuresis. The fractions significantly (P < 0.01) produced decreases in sperm counts and increased the percentage of defective sperm cells. There were significant (P < 0.05) increases in aspartate aminotransferase (AST) and blood urea nitrogen (BUN). Histopathological studies showed mild kidney and cardiac hyperaemia, slight hepatic degeneration and severe necrosis of the germinal epithelium of the testes. This study calls for some level of caution in the use of these roots and its extracts/fractions in traditional medicine for treating diseases. On the other hand, it could be a good source of drug for birth control.     

Phytochemical Characterization and Bioactivity of Asparagus acutifolius: A Focus on Antioxidant,Cytotoxic, Lipase Inhibitory and Antimicrobial Activities

The phytochemical composition of leaves, stems, pericarps and rhizomes ethanolic extracts of Asparagus acutifolius were characterized by HPLC-DAD-MS. A. acutifolius samples contain at least eleven simple phenolics, one flavonon, two flavonols and six steroidal saponins. The stem extracts showed the highest total phenolic acid and flavonoid contents, where cafeic acid and rutin were the main compounds. No flavonoids were detected in the leaf, pericarp or rhizome while caffeic acid and ferulic acid were the predominant. Steroidal saponins were detected in the different plant parts of A. acutifolius, and the highest contents were found in the rhizome extracts. The stem extracts exhibited the highest antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) and the highest 2,2-azino-bis (3 ethylbenzothiazoline-6-sulphonic acid) (ABTS) scavenging activity was found in the pericarp extracts. The rhizome and leaf extracts showed a potent cytotoxic activity against HCT-116 and HepG2 cell lines. Moreover, the pericarp and rhizome extracts revealed a moderate lipase inhibitory activity. The leaf and rhizome extracts were screened for their antimicrobial activity against human pathogenic isolates. The leaf extract exhibited a powerful inhibitory activity against all the bacteria and fungi tested.     

Chemical characterization,computational analysis and biological views on Daphne gnidioides Jaub. & Spach extracts: Can a new raw material be provided for biopharmaceutical applications?

The scientific world tends to turn to natural products such as medicinal and aromatic plants because of the inadequacy of commercially available synthetic drugs as antibiotics or anticancer, and their adverse effects on healthy tissues. One of these plants is Daphne gnidioides Jaub. & Spach, which belongs to the Thymelaeaceae family, and there is no data in the literature on its biological activity. This study is aimed to elucidate the chemical profiles and in vitro anticancer, antibacterial and DNA protection and enzyme inhibitory properties of methanol extracts of root, stem, and leaf of D. gnidioides Jaub. & Spach. Polyphenolic components of the extracts were characterized by HPLC-MS/MS. The highest phenolic content was detected in the leaf extract (TIPC = 43.5 ± 0.5 mg/g DE), followed by stem (TIPC = 27.3 ± 0.7 mg/g DE) and root (TIPC = 18.3 ± 0.2 mg/g DE) extracts. Vicenin-2 and 3-O-p-coumaroyl-5-O-caffeoylquinic acid were the main identified compounds in leaf and both root and stem extracts, respectively. The extracts did not show any protective effect on DNA against experimental Fenton’s reagent. The minimum inhibitory concentration and the minimum bactericidal concentration values for the root and leaf extracts against tested bacterial strains ranged from 31.25 to 500 μg/mL. After 48 h interaction of the cancer cell lines with the extracts, only the stem extract had significant cytotoxicity on HeLa cells (IC₅₀ = 86.16 μg/mL). No remarkable activity of the extracts, which was tested against MDA-MB-231, was detected (IC₅₀ > 1000 μg/mL). These data showed that D. gnidioides Jaub. & Spach stem extract inhibited the survival of HeLa cells in a time-dependent manner. After the treatment of IC₅₀ concentration of stem extract with HeLa cells, an increase in LC3-II autophagic gene expression was detected. Also, the extracts exhibited significant tyrosinase inhibitory effects which were confirmed by molecular docking. To sum up, the tested extracts could be used as a starting point for the development of new multifunctional drugs.     

Water-in-Oil-in-Water Nanoemulsions Containing Temulawak (Curcuma xanthorriza Roxb) and Red Dragon Fruit (Hylocereus polyrhizus) Extracts

Hydrophobic curcumin in temulawak extract and hydrophilic betacyanin in red dragon fruit extract are high-value bioactive compounds with extensive applications in functional food. In this study, these extracts were encapsulated in water-in-oil-in-water (w/o/w) nanoemulsions as a delivery system using a two-step high-energy emulsification method. PGPR and Span 20 were used as lipophilic emulsifiers for the primary w/o emulsion. The most stable w/o/w formulation with the least oil phase separation of 5% v/v consisted of w/o emulsion (15% w/w) and Tween 80 (1.5% w/w) as hydrophilic emulsifier. The formulation was characterized by a 189-nm mean droplet diameter, 0.16 polydispersity index, and –32 mV zeta potential. The freeze–thaw stability may be attributed to the combination of low w/o emulsion content and high Tween 80 concentration in the outer water phase of the w/o/w nanoemulsions used in this study. The IC₅₀ values of the nanoemulsion and the red dragon fruit extract were similar. It means that the higher concentration of curcumin in the nanoemulsions and the lower IC₅₀ value of temulawak extract ensured sufficient antioxidant activities of the w/o/w nanoemulsions.     

Phytochemical Profile,Antioxidant Capacity, α-Amylase and α-Glucosidase Inhibitory Potential of Wild Moroccan Inula viscosa (L.) Aiton Leaves

Medicinal plants offer imperative sources of innovative chemical substances with important potential therapeutic effects. Among them, the members of the genus Inula have been widely used in traditional medicine for the treatment of several diseases. The present study investigated the antioxidant (DPPH, ABTS and FRAP assays) and the in vitro anti-hyperglycemic potential of aerial parts of Inula viscosa (L.) Aiton (I. viscosa) extracts through the inhibition of digestive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. The polyphenolic profile of the Inula viscosa (L.) Aiton EtOAc extract was also investigated using HPLC-DAD/ESI-MS analysis, whereas the volatile composition was elucidated by GC-MS. The chemical analysis resulted in the detection of twenty-one polyphenolic compounds, whereas the volatile profile highlighted the occurrence of forty-eight different compounds. Inula viscosa (L.) Aiton presented values as high as 87.2 ± 0.50 mg GAE/g and 78.6 ± 0.55mg CE/g, for gallic acid and catechin, respectively. The EtOAc extract exhibited the higher antioxidant activity compared to methanol and chloroform extracts in different tests with (IC₅₀ = 0.6 ± 0.03 µg/mL; IC₅₀ = 8.6 ± 0.08 µg/mL; 634.8 mg ± 1.45 AAE/g extract) in DPPH, ABTS and FRAP tests. Moreover, Inula viscosa (L.) Aiton leaves did show an important inhibitory effect against α-amylase and α-glucosidase. On the basis of the results achieved, such a species represents a promising traditional medicine, thanks to its remarkable content of functional bioactive compounds, thus opening new prospects for research and innovative phytopharmaceuticals developments.     

Metabolomic Profiling and Antioxidant Activities of Breonadia salicina Using 1H-NMR and UPLC-QTOF-MS Analysis

Breonadia salicina (Vahl) Hepper and J.R.I. Wood is widely used in South Africa and some other African countries for treatment of various infectious diseases such as diarrhea, fevers, cancer, diabetes and malaria. However, little is known about the active constituents associated with the biological activities. This study is aimed at exploring the metabolomics profile and antioxidant constituents of B. salicina. The chemical profiles of the leaf, stem bark and root of B. salicina were comprehensively characterized using proton nuclear magnetic resonance (¹H-NMR) spectroscopy and ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). The antioxidant activities of the crude extracts, fractions and pure compounds were determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging and reducing power assays. A total of 25 compounds were tentatively identified using the UPLC-QTOF-MS. Furthermore, the ¹H-NMR fingerprint revealed that the different parts of plant had differences and similarities among the different crude extracts and fractions. The crude extracts and fractions of the root, stem bark and leaf showed the presence of α-glucose, β-glucose, glucose and fructose. However, catechin was not found in the stem bark crude extracts but was found in the fractions of the stem bark. Lupeol was present only in the root crude extract and fractions of the stem bark. Furthermore, 5-O-caffeoylquinic acid was identified in the methanol leaf extract and its respective fractions, while the crude extracts and fractions from the root and dichloromethane leaf revealed the presence of hexadecane. Column chromatography and preparative thin-layer chromatography were used to isolate kaempferol 3-O-(2″-O-galloyl)-glucuronide, lupeol, d-galactopyranose, bodinioside Q, 5-O-caffeoylquinic acid, sucrose, hexadecane and palmitic acid. The crude methanol stem bark showed the highest antioxidant activity in the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity with an IC₅₀ value of 41.7263 ± 7.6401 μg/mL, whereas the root crude extract had the highest reducing power activity with an IC_0.5 value of 0.1481 ± 0.1441 μg/mL. Furthermore, the ¹H-NMR and UPLC-QTOF-MS profiles showed the presence of hydroxycinnamic acids, polyphenols and flavonoids. According to a literature survey, these phytochemicals have been reported to display antioxidant activities. Therefore, the identified hydroxycinnamic acid (caffeic acid), polyphenol (ellagic acid) and flavonoids (catechin and (epi) gallocatechin) significantly contribute to the antioxidant activity of the different parts of plant of B. salicina. The results obtained in this study provides information about the phytochemistry and phytochemical compositions of Breonadia salicina, confirming that the species is promising in obtaining constituents with medicinal potential primarily antioxidant potential.     

The simple solvent-free synthesis of 1H-quinazoline-2,4-diones using supercritical carbon dioxide and catalytic amount of base

Only supercritical carbon dioxide (scCO₂) as a reactant and a solvent, and catalytic amount of base (DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), DBN (1,5-diazabicyclo[4.3.0]non-5-ene), Dabco^® (1,4-diazabicyclo[2.2.2]octane), and triethylamine) afforded 1H-quinazoline-2,4-diones in good to excellent yields from 2-aminobenzonitriles. 6,7-Dimethoxy-1H-quinazoline-2,4-dione, which is a key intermediate of medicines (Prazosin, Bunazosin, and Doxazosin) was synthesized successfully in a 97% yield, using 0.1 equiv of DBU under scCO₂ (10 MPa) at 80 °C.     

Assessment of antioxidant and cytotoxic potential of silver nanoparticles synthesized from root extract of Reynoutria japonica Houtt

Free radicals, mostly consist of reactive oxygen species, are generated in human body by several exogenous and endogenous systems. Overproduction of free radicals is known to cause several degenerative disorders including cancer. The aim of this study is to synthesize silver nanoparticles (AgNPs) using root extract of Reynoutria japonica and to investigate its antioxidant and cytotoxic potential. AgNPs were synthesized by green approach and subsequently characterized using UV–vis spectroscopy, SEM, TEM, FTIR, XRD, EDS and DLS. The antioxidant activity was investigated using DPPH, FRAP, H₂O₂, and ABT?⁺ radical scavenging assays while the cytotoxic effect was assessed using different human cancer cell lines including lung (A549), liver (Hep-G2) and breast (MDA-MB-231) by MTS assay. Moreover, the specificity of NPs was assessed against two normal human cell lines e.g. alveolar and renal primary epithelial cells (HPAEpiC and HRPTEpiC). The UV–vis spectra confirmed the synthesis of AgNPs by producing a characteristic peak at 410 nm. Further analysis confirmed that AgNPs were crystalline in nature, predominantly spherical in shape, with an average width and area of 17.34 nm and 164.46 nm², respectively. DLS analysis revealed that NPs possess a high negative zeta potential value (?28.5 mV), thus facilitating its electrostatic stabilization. AgNPs showed dose dependent antioxidant activity against DPPH, FRAP, H₂O₂ and ABTS with IC₅₀ values 19.25, 22.45, 24.20 and 18.88 µg/ml, respectively. The AgNPs depicted significant cytotoxic effects against A549, Hep-G2 and MDA-MB-231 cell lines with IC₅₀ values of 4.5, 5.1 and 3.46 µg/ml, respectively. Moreover, the NPs exhibited highest selectivity index (>2.0) for A549, Hep-G2 and MDA-MB-231, confirming its specificity towards cancer cell lines. In conclusion, AgNPs prepared from root extract of R. japonica possess strong antioxidant and cytotoxic potential which suggests that they should be investigated further in order to develop safe and effective antioxidant and/or cytotoxic formulations.     

Setup of an Ultrasonic-Assisted Extraction to Obtain High Phenolic Recovery in Crataegus monogyna Leaves

Hawthorn leaves are a rich source of phenolic compounds that possess beneficial activities for human health. Ultrasonic-assisted extraction (UAE) is an extraction technique frequently used for the isolation of phenolic compounds in plants. Thus, in this study, a Box–Behnken design was used to optimize UAE conditions such as the percentage of acetone, the extraction time and solvent-to-solid ratio (v/w) in order to obtain the maximum content of total compounds by Folin–Ciocalteu and the maximum in vitro antioxidant activity by DPPH, ABTS and FRAP assays in Crataegus monogyna leaves. The optimum conditions to obtain the highest total phenolic content and antioxidant activities were 50% acetone, 55 min and 1/1000 (w/v). A total of 30 phenolic compounds were identified and quantified in C. monogyna leaf extract obtained at these optimum UAE conditions. HPLC-MS allows the identification and quantification of 19 phenolic compounds and NP-HPLC-FLD analyses showed the presence of 11 proanthocyanidins. According to the results, the most concentrated phenolic compounds in C. monogyna leaf extract obtained at optimum UAE conditions were phenolic acid derivatives such as protocatechuic acid-glucoside, dihydroxy benzoic acid pentoside and chlorogenic acid, flavones such as 2″-O-rhamnosyl-C-hexosyl-apigenin, flavonols such as hyperoside and isoquercetin and proanthocyanidins such as monomer and dimer. As a result, the optimized UAE conditions could be used to obtain an extract of C. monogyna leaves enriched with phenolic compounds.