Antidiabetic, antioxidant, molecular docking and HPTLC analysis of miquelianin isolated from Euphorbia schimperi C. Presl

Primary Antioxidant Power and Mpro SARS-CoV-2 Non-Covalent Inhibition Capabilities of Miquelianin

The antioxidant power of quercetin-3-O-glucuronide (miquelianin) has been studied, at the density functional level of theory, in both lipid-like and aqueous environments. In the aqueous phase, the computed pKa equilibria allowed the identification of the neutral and charged species present in solution that can react with the ⋅OOH radical. The Hydrogen Atom Transfer (HAT), Single Electron Transfer (SET) and Radical Adduct Formation (RAF) mechanisms were considered, and the individual, total and fraction corrected rate constants were obtained. Potential non-covalent inhibition of Mpro from SARS-CoV-2 by miquelianin has been also evaluated.

Flavonoids as dual-target inhibitors against α-glucosidase and α-amylase: a systematic review of in vitro studies

Diabetes mellitus remains a major global health issue, and great attention is directed at natural therapeutics. This systematic review aimed to assess the potential of flavonoids as antidiabetic agents by investigating their inhibitory effects on α-glucosidase and α-amylase, two key enzymes involved in starch digestion. Six scientific databases (PubMed, Virtual Health Library, EMBASE, SCOPUS, Web of Science, and WHO Global Index Medicus) were searched until August 21, 2022, for in vitro studies reporting IC50 values of purified flavonoids on α-amylase and α-glucosidase, along with corresponding data for acarbose as a positive control. A total of 339 eligible articles were analyzed, resulting in the retrieval of 1643 flavonoid structures. These structures were rigorously standardized and curated, yielding 974 unique compounds, among which 177 flavonoids exhibited inhibition of both α-glucosidase and α-amylase are presented. Quality assessment utilizing a modified CONSORT checklist and structure-activity relationship (SAR) analysis were performed, revealing crucial features for the simultaneous inhibition of flavonoids against both enzymes. Moreover, the review also addressed several limitations in the current research landscape and proposed potential solutions. The curated datasets are available online at https://github.com/MedChemUMP/FDIGA .

Engineered production of bioactive polyphenolic O-glycosides

Polyphenolic compounds (such as quercetin and resveratrol) possess potential medicinal values due to their various bioactivities, but poor water solubility hinders their health benefits to humankind. Glycosylation is a well-known post-modification method to biosynthesize natural product glycosides with improved hydrophilicity. Glycosylation has profound effects on decreasing toxicity, increasing bioavailability and stability, together with changing bioactivity of polyphenolic compounds. Therefore, polyphenolic glycosides can be used as food additives, therapeutics, and nutraceuticals. Engineered biosynthesis provides an environmentally friendly and cost-effective approach to generate polyphenolic glycosides through the use of various glycosyltransferases (GTs) and sugar biosynthetic enzymes. GTs transfer the sugar moieties from nucleotide-activated diphosphate sugar (NDP-sugar) donors to sugar acceptors such as polyphenolic compounds. In this review, we systematically review and summarize the representative polyphenolic O-glycosides with various bioactivities and their engineered biosynthesis in microbes with different biotechnological strategies. We also review the major routes towards NDP-sugar formation in microbes, which is significant for producing unusual or novel glycosides. Finally, we discuss the trends in NDP-sugar based glycosylation research to promote the development of prodrugs that positively impact human health and wellness.

[Induced biosynthesis of fengycin and surfactin in a strain of Bacillus amyloliquefaciens with oomyceticidal activity on zoospores of Phytophthora capsici]

A potential alternative to the use of chemical products with oomyceticidal action for the control of Phytophthora capsici in vegetables is the use of antimicrobial metabolites, biosynthesized in Bacillus species. The objective of this study was to induce the biosynthesis of lipopeptides in Bacillus amyloliquefaciens KX953161.1 by using glutamic acid, iron, cellulose, chitin, or inactive Colletotrichum spp. cells. The in vitro oomyceticidal effect of the bacterial lipopeptides on zoospores of Phytophthora capsici was evaluated. The lipopeptides identified and quantified in the crude extracts by high performance thin layer chromatography (HPTLC) were fengycin and surfactin. The bacterial culture with inactive fungal cells yielded the greatest biosynthesis of lipopeptides, at 1847.02± 11.8 and 2563.45± 18.4 μg/ml of fengycin and surfactin, respectively and the treatments that obtained lower production of these lipopeptides, were those to which iron and cellulose were added with 608.05 ± 22.6 and 903.74± 22.1; 563.31± 11.9 and 936.96± 41.1 μg/ml for fengicin and surfactin, respectively. The lipopeptide extracted showed 100% germination inhibition on zoospores of P. capsici, revealing encystment, malformations in the germ tube and cellular degradation. Lipopeptides have the potential to control P. capsici; however, the biosynthesis of these lipopeptides requires further study to determine their biological mode of action and optimize lipopeptide performance and profile.

Medicinal Plants Used for Dermatological Disorders among the People of the Kingdom of Saudi Arabia: A Narrative Review

Historically, skin disorders have received less attention in health management than other life-threatening diseases that occur on a global scale. However, numerous skin problems are reported to primary health care systems worldwide, particularly in tropical locations. While modern physicians often address most skin conditions, it is estimated that over 70% of individuals with skin illnesses do not seek treatment. Traditional medicine dates all the way back to human civilization's inception. Numerous materials are utilized in traditional medicinal remedies, but the use of plants is particularly critical. Saudi Arabia is one of the world's most botanically varied countries, having an extensive folk medicine heritage. While several reviews on the use of plants to cure skin disorders has been published worldwide, very few have been undertaken in Saudi Arabia, much alone a comprehensive one. Thus, the present review identified the most significant and medicinally relevant herbs used in the treatment of various dermatological conditions in Saudi Arabia. A total of 43 plants were identified and described in this study. This investigation omitted publications that lacked detailed data and had only fragmented information regarding the herb's traditional use in topical applications.

Four almost unexplored species of Brazilian Connarus (Connaraceae): Chemical composition by ESI-QTof-MS/MS-GNPS and a pharmacologic potential

INTRODUCTION

Species of Connaraceae are globally used in traditional medicines. However, several of these have not been studied regarding their chemical composition, and some are even at risk of extinction without proper studies. Therefore, the chemical composition and pharmacological potential of Connarus blanchetii Planch., Connarus nodosus Baker, Connarus regnellii G. Schellenb., and Connarus suberosus Planch., which were previously unknown, were analyzed.

OBJECTIVE

This work aims to investigate the pharmacological potential of these four Connarus species. The chemical composition of different extracts was determined by high-resolution mass spectrometry (HRMS), with subsequent analysis by the GNPS platform and competitive fragmentation modeling (CFM).

MATERIALS AND METHODS

Leaf extracts (C. blanchetii, C. nodosus, C. regnellii, and C. suberosus) and bark extracts (C. regnellii and C. suberosus) were obtained by decoction, infusion, and maceration. LC/HRMS data were submitted to the GNPS platform and evaluated using CFM in order to confirm the structures.

RESULTS

The HRMS-GNPS/CFM analysis indicated the presence of 23 compounds that were mainly identified as phenolic derivatives from quercetin and myricetin, of which 21 are unedited in the Connarus genus. Thus, from the analyses performed, we can identify different compounds with pharmacological potential, as well as the most suitable forms of extraction.

CONCLUSION

Using HRMS-GNPS/CFM, 21 unpublished compounds were identified in the studied species. Therefore, our combination of data analysis techniques can be used to determine their chemical composition.

Synthesis, in vivo and in silico analgesic and anti-inflammatory studies of α-D-ribofuranose derivatives

Five α-D-ribofuranose analogues (2, 3, 4, 5 and 6) were synthesized in good yields from 3-O-benzyl-4-C-(hydroxymethyl)-1, 2-O-isopropylidene-α-D-ribofuranose (1). The synthesized compounds were then subjected to analgesic, anti-inflammatory, antimicrobial and antioxidant assays. Compound 3 demonstrated 79.74% (P < 0.001) writhing inhibition and highest reaction time of 2.55 ± 0.13 min (P < 0.001) after 30 min of oral administration in peripheral and central analgesic assay, respectively, at 50 mg/kg dose. Compound 2 and 6 exhibited significant anti-inflammatory activity at 100 mg/kg dose with paw edema inhibition of 91.15% (P < 0.001) and 95.13% (P < 0.001), respectively, in 4th hour. The synthesized analogues did not show notable antioxidant and antibacterial properties. Molecular docking study revealed higher binding affinity of −8.1 kcal/mol and −8.9 kcal/mol of compound 3 towards cyclooxygenase-1 and phospholipase A_2, respectively, compared to −7.7 and −7.6 kcal/mol respectively for corresponding native ligands. Compound 2 demonstrated binding affinity of −9.1 kcal/mol towards interleukin-1 receptor-associated kinase-4 compared to −8.7 kcal/mol of the native ligand. The molecular properties related to drug likeness of compounds were found to be within acceptable range. Synthesized D-ribofuranose analogues demonstrated promising analgesic and anti-inflammatory activities and further development may lead to new potent analgesic and anti-inflammatory agents.

Exploration of Diosmin to Control Diabetes and Its Complications-an In Vitro and In Silico Approach

BACKGROUND

Diosmin is a flavonoid obtained from the citrus fruits of the plants. Diosmin has blood lipid lowering activities, antioxidant activity, enhances venous tone and microcirculation, protects capillaries, mainly by reducing systemic oxidative stress.

OBJECTIVE

The present study demonstrates the potential of Diosmin against the enzymes aldose reductase, α-glucosidase, and α-amylase involved in diabetes and its complications by in vitro evaluation and reverse molecular docking studies.

METHODS

The assay of aldose reductase was performed by using NADPH as starting material and DL-Glyceraldehyde as a substrate. DNS method was used for alpha amylase inhibition and in alpha glucosidase inhibitory activity p-nitrophenyl glucopyranoside (pNPG) was used as substrate. The reverse molecular docking studies was performed by using Molegro software (MVD) with grid resolution of 30 Å.

RESULTS

Diosmin shows potent inhibitory effect against aldose reductase (IC50:333.88±0.04 μg/mL), α-glucosidase (IC50:410.3±0.01 μg/mL) and α-amylase (IC50: 404.22±0.02 μg/mL) respectively. The standard drugs shows moderate inhibitory activity for enzymes. The MolDock Score of Diosmin was -224.127 against aldose reductase, -168.17 against α-glucosidase and - 176.013 against α-amylase respectively, which was much higher than standard drugs.

CONCLUSION

From the result it was concluded that diosmin was a potentially inhibitor of aldose reductase, alpha amylase and alpha glucosidase enzymes then the standard drugs and it will be helpful in the management of diabetes and its complications. This will also be benevolent to decrease the socio economical burden on the middle class family of the society.

Development and Validation of a Method for Determining the Quercetin-3-O-glucuronide and Ellagic Acid Content of Common Evening Primrose (Oenothera biennis) by HPLC-UVD

Toward the standardization of common evening primrose (Oenothera biennis) sprout extract (OBS-E), we aimed to obtain indicator compounds and use a validated method. HPLC-UVD allowed simultaneous quantification of the indicator compounds quercetin-3-O-glucuronide and ellagic acid. The method was validated in terms of specificity, linearity, precision, accuracy, and limit of detection/limit of quantification (LOD/LOQ). High specificity and linearity was demonstrated, with correlation coefficients of 1.0000 for quercetin-3-O-glucuronide and 0.9998 for ellagic acid. The LOD/LOQ values were 0.486/1.472 μg/mL for quercetin-3-O-glucuronide and 1.003/3.039 μg/mL for ellagic acid. Intra-day and inter-day variability tests produced relative standard deviation for each compound of <2%, a generally accepted precision criterion. High recovery rate were also obtained, indicating accuracy validation. The OBS-E prepared using various concentrations of ethanol were then analyzed. The 50% ethanol extract had highest content of quercetin-3-O-glucuronide, whereas the 70% ethanol extract possessed the lowest. However, the ellagic acid content was highest in the 70% ethanol extract and lowest in the 90% ethanol extract. Thus, quercetin-3-O-glucuronide and ellagic acid can be used industrially as indicator compounds for O. biennis sprout products, and our validated method can be used to establish indicator compounds for other natural products.

Antioxidant and antidiabetic activities of vanadium-binding protein and trifuhalol A

The antioxidant and antidiabetic activities of vanadium-binding protein (VBP) and trifuhalol A, alone or combined, were investigated. Both VBP and trifuhalol A showed potent radical scavenging activity (RSA) on 2,2'-azinobis (3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), hydrogen peroxide, and ferric-reducing antioxidant power. Their combination at a concentration of 100 μg/ml VBP and 40 μg/ml trifuhalol A exhibited more than 99% RSA against ABTS. Additionally, VBP and trifuhalol A, alone or combined, displayed potential antidiabetic activities against Saccharomyces cerevisiae α-glucosidase. The highest inhibition of 70.26% against S. cerevisiae α-glucosidase was observed in the case of the combination of 250 μg/ml VBP and 1.75 μg/ml trifuhalol A. Kinetics study revealed that VBP and trifuhalol A were noncompetitive inhibition type against S. cerevisiae α-glucosidase, while VBP and trifuhalol A combined treatment was a mixed inhibition type against S. cerevisiae α-glucosidase. These results indicated that VBP and trifuhalol A, alone or combined, had high free radical scavenging activity and inhibitory activity against S. cerevisiae a-glucosidase, suggesting that VBP and trifuhalol A could be used as candidates for the development of natural antidiabetic drugs or functional food. PRACTICAL APPLICATIONS: The present study showed that VBP and trifuhalol A, alone or combined, had potential antioxidant and antidiabetic activities, suggesting that VBP and trifuhalol A could be developed to a novel nutraceutical or natural antidiabetic drugs in the management of obesity or diabetes. This finding will be beneficial for all peoples who are directly or indirectly associated with obesity or diabetes.

Saururus chinensis-controlled allergic pulmonary disease through NF-κB/COX-2 and PGE2 pathways

Saururus chinensis is a perennial herb found in the northeastern regions of Asia, including Korea, China, and Japan, and is used in traditional medicine. Studies have identified the four major constituents in Saururus chinensis water extract (LHF618^®) as miquelianin (11.75 ± 0.092 mg/g), rutin (1.20 ± 0.008 mg/g), quercitrin (2.38 ± 0.389 mg/g), and quercetin (0.068 ± 0.017 mg/g). Saururus chinensis can improve the symptoms of ovalbumin- or fine dust-induced allergic pulmonary disease by suppressing the effects of WBCs and neutrophils in BALF and IgE in the serum. Saururus chinensis dose-dependently recovered morphological changes such as mucous hyper secretion (from 2.7 ± 0.46 to 0.6 ± 0.65), pulmonary epithelial cell hyperplasia (from 2.4 ± 0.55 to 0.7 ± 0.67), and inflammatory cell infiltration (from 2.3 ± 0.45 to 0.6 ± 0.43), and effectively controlled cDNA levels and protein levels of IL-13. It inhibited NF-κB translocation and COX-2 protein synthesis and suppressed the expression of PGE₂. Our results show that Saururus chinensis controlled allergic pulmonary disease via the anti-inflammatory pathways, NF-κB/COX-2 and PGE₂. Saururus chinensis may be a promising drug candidate against fine dust-induced allergic pulmonary disease.

Simultaneous Determination of 6-Shogaol and 6-Gingerol in Various Ginger (Zingiber officinale Roscoe) Extracts and Commercial Formulations Using a Green RP-HPTLC-Densitometry Method

Various analytical methodologies have been reported for the determination of 6-shogaol (6-SHO) and 6-gingerol (6-GIN) in ginger extracts and commercial formulations. However, green analytical methods for the determination of 6-SHO and 6-GIN, either alone or in combination, have not yet been reported in literature. Hence, the present study was aimed to develop a rapid, simple, and cheaper green reversed phase high-performance thin-layer chromatography (RP-HPTLC) densitometry method for the simultaneous determination of 6-SHO and 6-GIN in the traditional and ultrasonication-assisted extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas. The simultaneous analysis of 6-SHO and 6-GIN was carried out via RP-18 silica gel 60 F254S HPTLC plates. The mixture of green solvents, i.e., ethanol:water (6.5:3.5 v/v) was utilized as a mobile phase for the simultaneous analysis of 6-SHO and 6-GIN. The analysis of 6-SHO and 6-GIN was performed at λmax = 200 nm for 6-SHO and 6-GIN. The densitograms of 6-SHO and 6-GIN from traditional and ultrasonication-assisted extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas were verified by obtaining their single band at Rf = 0.36 ± 0.01 for 6-SHO and Rf = 0.53 ± 0.01 for 6-GIN, compared to standard 6-SHO and 6-GIN. The green RP-HPTLC method was found to be linear, in the range of 100-700 ng/band with R2 = 0.9988 for 6-SHO and 50-600 ng/band with R2 = 0.9995 for 6-GIN. In addition, the method was recorded as "accurate, precise, robust and sensitive" for the simultaneous quantification of 6-SHO and 6-GIN in traditional and ultrasonication-assisted extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas. The amount of 6-SHO in traditional extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas was obtained as 12.1, 17.9, 10.5, and 9.6 mg/g of extract, respectively. However, the amount of 6-SHO in ultrasonication-assisted extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas were obtained as 14.6, 19.7, 11.6, and 10.7 mg/g of extract, respectively. The amount of 6-GIN in traditional extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas were found as 10.2, 15.1, 7.3, and 6.9 mg/g of extract, respectively. However, the amount of 6-GIN in ultrasonication-assisted extracts of ginger rhizome, commercial ginger powder, commercial capsules, and commercial ginger teas were obtained as 12.7, 17.8, 8.8, and 7.9 mg/g of extract, respectively. Overall, the results of this study indicated that the proposed analytical technique could be effectively used for the simultaneous quantification of 6-SHO and 6-GIN in a wide range of plant extracts and commercial formulations.

New benzoic acid derivatives from Cassia italica growing in Saudi Arabia and their antioxidant activity

Two new benzoic acid derivatives: 1-p-hydroxy benzoyl-3-palmitoyl glycerol (1) and 6 -p-hydroxy benzoyl daucosterol (2), along with scutellarein-6-methyl ether (3), quercetin (4), and rutin (5) had been separated from Cassia italica (Fabaceae) aerial parts from EtOAc fraction. Their characterisation was accomplished by various spectroscopic techniques and by comparing with the published data. The Ethyl acetate (EtOAc) fraction and compounds 1–5 had been assessed for their antioxidant potential utilizing DPPH assay. They had significant antioxidant capacities with activity ranged from 19.7 to 95.8%, in comparison to butylated hydroxyanisole (BHA) (93.8%). These findings could provide a further evidence to support the traditional use of C. italica for the treatment of chronic or degenerative illnesses.

A Green RP-HPTLC-Densitometry Method for the Determination of Diosmin in Pharmaceutical Formulations

Green analytical technologies for the determination of a bioactive compound diosmin (DIOM) in the real samples of pharmaceutical formulations and biological fluids are scarce in literature. Therefore, the present investigation was carried out to develop a novel, rapid, simple, and economical green “reversed phase high-performance thin-layer chromatography (RP-HPTLC)” method for the determination of DIOM in commercial tablets and in-house developed spray-dried microparticles (MPs). The quantification of DIOM was conducted via “RP-18 silica gel 60 F254S HPTLC plates”. The binary combination of green solvents, i.e., ethanol:water (5.5:4.5 v/v) was proposed as a green mobile phase. The analysis of DIOM was conducted in absorbance/reflectance mode of densitometry at λmax = 348 nm. The densitograms of DIOM from the commercial tablets and in-house developed spray-dried MPs were verified by recording their single band at Rf = 0.80 ± 0.02 compared to standard DIOM. Green RP-HPTLC method was observed as linear in the range of 100–700 ng/band with R2 = 0.9995. The proposed method was found as “accurate, precise, robust, and sensitive” for the determination of DIOM in the real samples of commercial tablets and in-house developed spray-dried MPs. The % content of DIOM in the real samples of commercial tablets and in-house developed spray-dried MPs was obtained as 99.06 and 101.30%, respectively. The recorded results of this research suggested that the green RP-HPTLC method can be effectively used for the routine analysis of DIOM in pharmaceutical products.

Determination of Delafloxacin in Pharmaceutical Formulations Using a Green RP-HPTLC and NP-HPTLC Methods: A Comparative Study

In this work; delafloxacin (DLFX) was determined using a validated green RP-HPTLC and NP-HPTLC methods in commercial tablets and in-house developed solid lipid nanoparticles (SLNs). RP-HPTLC determination of DLFX was performed using "RP-18 silica gel 60 F254S HPTLC plates". However; NP-HPTLC estimation of DLFX was performed using "silica gel 60 F254S HPTLC plates". For a green RP-HPTLC method; the ternary combination of ethanol:water:ammonia solution (5:4:2 v/v/v) was used as green mobile phase. However; for NP-HPTLC method; the ternary mixture of ethyl acetate: methanol: ammonia solution (5:4:2 v/v/v) was used as normal mobile phase. The analysis of DLFX was conducted in absorbance/reflectance mode of densitometry at λmax = 295 nm for both methods. RP-HPTLC method was found more accurate, precise, robust and sensitive for the analysis of DLFX compared with the NP-HPTLC method. The % assay of DLFX in commercial tablets and in-house developed SLNs was determined as 98.2 and 101.0%, respectively, using the green RP-HPTLC technique, however; the % assay of DLFX in commercial tablets and in-house developed SLNs was found to be 94.4 and 95.0%, respectively, using the NP-HPTLC method. Overall, the green RP-HPTLC method was found superior over the NP-HPTLC. Therefore, the proposed green RP-HPTLC method can be successfully applied for analysis of DLFX in commercial tablets, SLNs and other formulations containing DLFX.

Ecofriendly densitometric RP-HPTLC method for determination of rivaroxaban in nanoparticle formulations using green solvents

A literature survey revealed no suitable “reversed phase-high performance thin layer chromatography (RP-HPTLC)” method for the analysis of rivaroxaban in nanoparticle (NP) formulations. Therefore, a novel rapid, simple, economical and environment friendly RP-HPTLC method has been established for the quantification of rivaroxaban in NP formulations and commercial tablets. RP-HPTLC analysis of rivaroxaban was performed using “RP-18 silica gel 60 F254S HPTLC plates”. The binary mixture of green solvents ethanol : water (7 : 3 v/v) was utilized as the mobile phase. The quantification of rivaroxaban was carried out in densitometric mode at λ_max = 253 nm. Rivaroxaban peaks from NP formulations was confirmed by comparing its single spot at R_f = 0.71 ± 0.02 with that of the standard. The proposed RP-HPTLC method was found to be linear in the range of 50–600 ng per band with R² = 0.9994. The equation for linear regression analysis was obtained as Y = 13.28x + 1189.4. The proposed RP-HPTLC technique was validated for “precision, accuracy, robustness and sensitivity”. The accuracy of the method was obtained as 97.97–99.67%. The % RSD in repeatability and intermediate precision was recorded as 0.46–0.64 and 0.48–0.86%, respectively. The LOD and LOQ for rivaroxaban were obtained as 18.45 and 55.35 ng per spot, respectively. The % content of rivaroxaban in marketed tablets and NPs was recorded as 99.20 and 98.08%, respectively. The proposed RP-HPTLC technique could be successfully applied for the pharmaceutical assay of rivaroxaban in NPs, marketed tablets and related formulations.

A literature survey revealed no suitable “reversed phase-high performance thin layer chromatography (RP-HPTLC)” method for the analysis of rivaroxaban in nanoparticle (NP) formulations.