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The present study was intended for the identification of secondary metabolites in acetone extract of the lichen Hypotrachyna cirrhata using UPLC-ESI-QToF-MS/MS and the detection of bioactive compounds. This study led to the identification of 22 metabolites based on their MS/MS spectra, accurate molecular masses, molecular formula from a comparison of the literature database (DNP), and fragmentation patterns. In addition, potent antioxidant and α-glucosidase inhibitory potentials of acetone extract of H. cirrhata motivated us to isolate 10 metabolites, which were characterized as salazinic acid ( 11 ), norlobaridone ( 12 ), atranorin ( 13 ), lecanoric acid ( 14 ), lichesterinic acid ( 15 ), protolichesterinic acid ( 16 ), methyl hematommate ( 17 ), iso-rhizonic acid ( 18 ), atranol ( 19 ), and methylatratate ( 20) based on their spectral data. All these isolates were assessed for their free radicals scavenging, radical-induced DNA damage, and intestinal α-glucosidase inhibitory activities. The results indicated that norlobaridone ( 12 ), lecanoric acid ( 14 ), methyl hematommate (17 ), and atranol ( 19 ) showed potent antioxidant activity, while depsidones (salazinic acid ( 11 ), norlobaridone ( 12 )) and a monophenolic compound (iso-rhizonic acid, ( 18 )) displayed significant intestinal α-glucosidase inhibitory activities ( p < 0.001), which is comparable to standard acarbose. These results were further correlated with molecular docking studies, which indicated that the alkyl chain of norlobaridione ( 12 ) is hooked into the finger-like cavity of the allosteric pocket; moreover, it also established Van der Waals interactions with hydrophobic residues of the allosteric pocket. Thus, the potency of norlobaridone to inhibit α-glucosidase enzyme might be associated with its allosteric binding. Also, MM-GBSA (Molecular Mechanics-Generalized Born Surface Area) binding free energies of salazinic acid ( 11 ) and norlobaridone ( 12 ) were superior to acarbose and may have contributed to their high activity compared to acarbose.

In connection with our continuous efforts in the synthesis of derivatives from major compounds isolated from traditional medicinal plants, in the present study we have attempted to synthesize the furan-conjugated aloe-emodin derivatives ( 5a-j ) using a three-component reaction. The synthesized derivatives were assessed for anticancer activity against five different cancer cell lines using the in vitro MTT assay and the results showed that most of the derivatives are potent against cancer cells comparing with the control. Compounds 5a and 5e showed excellent activity against all the cancer cells with less than 12.5 µM and arrested the cell cycle at the G0/G1 phase in both CAL27 and SCC9 cells. Compound 5e induces the early apoptosis in CAL27 cells and compounds 5a and 5e induce early and late apoptosis, respectively, in SCC9 cells. Moreover, compounds 5b , 5c , 5i , and 5j showed excellent anti-inflammatory activity in LPS-stimulated RAW 264.7 cells by inhibiting IL-6 production. The molecular docking studies revealed that compound 5e has strong interaction with the CLK kinase and protein kinase II through hydrogen binding Asp325 and Lys290.

In modern networks, a Network Intrusion Detection System (NIDS) is a critical security device for detecting unauthorized activity. The categorization effectiveness for minority classes is limited by the imbalanced class issues connected with the dataset. We propose an Imbalanced Generative Adversarial Network (IGAN) to address the problem of class imbalance by increasing the detection rate of minority classes while maintaining efficiency. To limit the effect of the minimum or maximum value on the overall features, the original data was normalized and one-hot encoded using data preprocessing. To address the issue of the low detection rate of minority attacks caused by the imbalance in the training data, we enrich the minority samples with IGAN. The ensemble of Lenet 5 and Long Short Term Memory (LSTM) is used to classify occurrences that are considered abnormal into various attack categories. The investigational findings demonstrate that the proposed approach outperforms the other deep learning approaches, achieving the best accuracy, precision, recall, TPR, FPR, and F1-score. The findings indicate that IGAN oversampling can enhance the detection rate of minority samples, hence improving overall accuracy. According to the data, the recommended technique valued performance measures far more than alternative approaches. The proposed method is found to achieve above 98% accuracy and classifies various attacks significantly well as compared to other classifiers.

In an on-going investigation of bioactive metabolites producing potential endophytic fungi, the strain Lasiodiplodia theobromae (SJF-1) was isolated from a medicinal plant Syzygium cumini. The cultural, morphological and molecular identification was done with the SJF-1 strain. The obtained gene sequence was deposited in NCBI with accession number MG 938644. The methanolic extract of SJF-1 strain possessed one major bioactive fraction, and it was purified by column chromatography. Further, it was identified as Mellein by various spectroscopic studies ( 1 H, 13 C, DEPT-135°, FT-IR, ESI-HR-MS and 2D NMR). Biologically, Mellein showed potent anti-Xanthomonas activity with minimum inhibitory concentration (MIC) values ranging from 1·9 to 62·5 μg ml -1 against 11 Xanthomonas strains, a broad-spectrum antimicrobial activity with MIC 7·8-31·25 μg ml -1 and 1·9-31·25 μg ml -1 towards both bacterial and fungal strains, respectively. The scanning electron microscope analysis proved the antimicrobial efficacy of a Mellein by rupturing the cell walls of Xanthomonas sp. Molecular docking studies further supported that the Mellein showed good binding interactions with the proteins of Xanthomonas sp. to reduce pathogenicity. Further, in silico pharmacological studies showed that this metabolite exhibited high gastrointestinal absorption properties and promising oral drug bioavailability. We report, anti-Xanthomonas, in silico docking and pharmacological studies of Mellein from (SJF-1) strain for the first time., (© 2022 Society for Applied Microbiology.)

Marine seaweeds are predominant for nutraceuticals and have been food source since ancient times and are currently being used in Chinese medicines and Japanese traditional medicines. In the present study, the chemical profile analysis of Halimeda gracilis was performed using UPLC-ESI-Q-TOF-MS E analysis and assessed for its anticancer activity. A cursory investigation of the total ion chromatograms of the both methanol (MHG) and ethyl acetate (EAHG) of H. gracilis extracts reveals that both extracts have different kind of metabolites including phenols and its derivatives, diterpenes, cinnamic acids derivatives etc. The in vitro anticancer activity of EAHG and MHG exhibiting significant activity and induced apoptosis against skin cancer cells by generating excessive ROS, damaging the mitochondrial membrane and nuclear components. Further, the western blot analysis showed that the EAHG and MHG downregulates the oncoproteins PI3K, AKT, p-AKT, and BcL2 and upregulates the apoptotic proteins Bax, Cyto C, p21, p53, Caspase 9 and Caspase 3. To best of our knowledge, this is the first report which implies the UPLC-ESI-Q-TOF-MS E based chemical profiling of H. gracilis and can be used for the treatment of cancer., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In an attempt to develop natural product-based anticancer agents, a series of novel piperazine-linked bergenin heterocyclic hybrids bearing arylthiazolyl (5a-e), benzothiazolyl (10a-i), and arylsulfonyl (13a-o) were synthesized using the classical Mannich reaction and evaluated for their anticancer activity. All the synthesized derivatives were assessed for in vitro cytotoxic activity against a panel of human cancer and normal cell lines and the results showed that most of the compounds exhibited significant cytotoxic activity against cancer cells and mild cytotoxicity against normal cells. In particular, the compounds 5a, 5c, 10f, and 13o showed potent cytotoxic activity against tongue and oral cancer cell lines compared to the parent compound (<100 μM). Considering the efficacy, the compounds 5a, 5c, 10f, and 13o were subjected to cell cycle analysis and the results indicated that the compounds mitigated the cell cycle progression at the G0/G1 phase in the tongue and oral cancer cell lines. Subsequently, the annexin V/PI staining assay demonstrated that the compounds 5a, 5c, 10f, and 13o induced early and late apoptosis against tongue cancer and necrosis against oral cancer. Further, gene expression analysis revealed that 5a, 5c, and 13o treatment regulated the BAX and BcL-2 expression and also the selected compounds significantly reduced the expression level of vimentin, oct-4, and nanog. In addition, molecular docking studies revealed that the selected derivatives have strong binding energy with the BcL2 protein and downregulates the expression. Taken together, the study results implied that these compounds are promising anticancer candidates by modulating the epithelial to mesenchymal transition axis and could be considered for further development of novel anticancer drugs., Competing Interests: The authors declare that there is no conflict of interest to disclose., (This journal is © The Royal Society of Chemistry.)

A new steroid (acylated C 21 pregnane steroid) was isolated from chloroform extract in phytochemical screening of Caralluma lasiantha . The isolated compound is found to be 3β-hydroxy-14β-(6'- carboxyphenyl)propionyloxypregn-5-en-20-one based on spectroscopic studies (IR, 1 H NMR, 13 C NMR, DEPT, COSY, HSQC, HMBC and ESI-MS). The isolated new steroid was tested against four bacterial strains and the activity was related to the structure of the molecule.

Background: The fingerprinting and quantification of marker compounds from medicinal plants is a domain of the herbal industry for quality/quantity control parameters., Objective: The main objective of this study is the application of the in situ ReactIR technique for measuring the concentration of different components during the extraction process of different medicinal plants., Method: In this study we have performed the extraction of two-marker compounds, viz. piperine from Piper nigrum and curcumin from Curcuma longa plants, using various solvents (dichloromethane and methanol). The progress of extraction was monitored using an in situ Fourier transform infrared (FTIR) probe instrument and an automated reactor., Results: In this communication, using the in situ ReactIR technique we developed a method which demonstrates the relative quantification of marker analytes, optimizes extraction time and type of solvents to be used for different analytes during the extraction process., Conclusions: To the best of our knowledge, this is the first report of relative quantification and structural information of marker compounds during the process of extraction using in situ FTIR., Highlights: The present study highlights the real-time monitoring, in situ quantification, and structural information of marker compounds during the process of extraction of medicinal plants using in situ FTIR., (© AOAC INTERNATIONAL 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Entada phaseoloides (Linn.) Merr. (Family: Fabaceae) is a well-known, traditional, medicinal plant that has been extensively used in the Ayurvedic system of medicine for centuries to combat a wide range of ailments., Objective: The goal of this work was to investigate the bioactive constituents from n-butanol extracts of Entada. phaseoloides and develop a method for the comprehensive characterization of saponins using liquid chromatography with an electrospray ionization quadrupole time-of-flight mass spectrometer (LC-ESI-QTOF-MS)., Methods: A hyphenated technique, ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS), has been proposed to integrate LC and MS together with NMR for structural elucidation. This method allowed comprehensive characterization of saponin glycosides from E. phaseoloides based on their MS/MS fragmentation study., Results: The phytochemical study of E. phaseoloides resulted in the isolation and identification of three bio-active constituents. Further, the UPLC-QTOF-MS/MS method led the structure elucidation of saponin constituents directly from crude extracts via comparison of the exact molecular masses from their MS/MS spectra. Identified common fragments m/z 648, 630, 498, 366, and 204 were used for the screening of saponin components., Conclusions: The present study summarizes the isolation and identification of bio-compounds from n-butanol extract and the demonstration of UPLC-QTOF-MS/MS analysis for the characterization of compounds in complex crude extracts. To the best of our knowledge, this is the first systematic study in structural characterization on complex saponins and other metabolites from crude extract of E. phaseoloides using UPLC-ESI-QTOF-MSE., Highlights: Rapid analysis and characterizations of three new saponins from E. phaseoloides using UPLC-ESI-QTOF-MSE were tentatively identified based on the mass fragmentation study., (© AOAC INTERNATIONAL 2020. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

In connection with our continuous efforts to generate new derivatives from lead compounds isolated from traditional medicinal plants, a series of aloe-emodin derivatives ( 6a-6e ) were synthesized and assessed for their potential anticancer activity against a panel of cancer cell lines. The results showed that most of the derivatives are more active than the aloe-emodin and particularly, 6b and 6e manifested potent activity with IC 50 values of 1.32 & 1.6 μM and 0.99 & 2.68 μM against MDA-MB-231 and MCF-7 cells, respectively. Moreover, 6b and 6e induce early and late apoptosis as well as arrest the cell cycle at the G2/M phase in MDA-MB-231 cells. In conclusion, the results confirmed that the aloe-emodin derivatives could be a potential drug candidate for better treatment of breast cancer., Competing Interests: There is no conflict of interest to declare., (This journal is © The Royal Society of Chemistry.)

A new reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed for the separation and identification of impurities present in metadoxine. Herein, we report that one of the impurities eluted from the metadoxine sample is 4-deoxypyridoxine hydrochloride (4-DPH). In HPLC analysis, the retention time (RT) of 4-DPH was observed to be at 13.5 min in both the reference and metadoxine samples and the relative retention time (RRT) was 1.71. The presence of 4-DPH in a metadoxine sample was also confirmed by a chromatogram obtained by spiking the 4-DPH standard into the sample. Furthermore, the elution and mass of impurity 4-DPH in metadoxine was proven by LC-mass spectroscopy studies. This method highlights the presence of another unknown impurity that has so far not been observed in earlier methods of metadoxine evaluation. Hence, the developed method achieved superior resolution between metadoxine and impurities and thereby facilitates the production of a purer metadoxine drug.

Non-enzymatic reactions between proteins and methylglyoxal (MG) result in the formation of advanced glycation end products (AGEs). These AGEs play a vital role in the development of diabetic complications by stimulating oxidative stress and acting upon their receptor RAGE (Receptor for Advanced Glycation End products). This study examined the effect of aqueous methanol extract of Bombax ceiba L. calyxes (BCCE) on MG induced protein glycation and oxidative stress, followed by the identification of phytometabolites present in the calyxes using gas chromatography-mass spectrometry (GC-MS). The study revealed that priming of bovine serum albumin protein with the BCCE inhibited MG induced AGE formation in vitro and restrained AGE-induced RAGE up-regulation in HEK-293 cells. The BCCE significantly (p < 0.001) reduced the MG induced increase in reactive oxygen species (ROS), NADPH oxidase (NOX), and mitochondrial dysfunction. Improvements in the levels of antioxidant enzymes such as Mn and Cu/Zn-superoxide dismutase and glutathione reductase were also observed in HEK-293 cells. Furthermore, the decrease in primary cellular defense against AGEs, the glyoxalase 1 (Glo-1) activity, due to MG treatment was restored in BCCE treated cells. GC-MS analysis revealed the presence of antioxidant and antiglycation compounds such as myo-ionisitol, scopoletin, d-sedoheptulose, succinic acid, and xylitol in B. ceiba calyxes. The observed beneficial effect in our study might be attributed to the presence of these compounds in B. Ceiba calyxes. This is the first report presenting the antioxidant and antiglycation activities of B. ceiba calyxes and GC-MS analysis of active phytometabolites. These observations show that B. ceiba calyxes may become a potent and promising functional food to manage/control the development of diabetic complications.

Boswellia serrata is a widely used herb in Indian systems of medicine and is well known for its potential medicinal properties. A chromatographic method was developed for the analysis and quantification of six boswellic acid marker compounds, i.e., keto boswellic acid ( 1 ), 3-O-Acetyl 11-keto β-boswellic acid ( 2 ), ɑ-Boswellic acid ( 3 ), β-Boswellic acid ( 4 ), 3-O-Acetyl-ɑ-boswellic acid ( 5 ) and 3-O-Acetyl-β-boswellic acid ( 6 ) in commercial herbal products containing B. serrata as an ingredient. Combining UPLC with Q-Tof-MS/MS makes the better identification of secondary metabolites and adulterants in the herbal formulations containing B. serrata in rapid time using fragmentation approach than the traditional approaches. In this study quantification of boswellic acids with UPLC-PDA method was performed as per the pharmacopeia guidelines. Furthermore, minor phytochemical constituents were identified and characterized with the help of LC-Q-Tof-MS/MS fragmentation data and various isoforms of boswellic acids and tirucallic acids in B. serrata oleo-gum-resin extract were identified., (© 2019 Xi'an Jiaotong University. Production and hosting by Elsevier B.V.)

Limonoids found to be chemotaxonomic markers from the plants of the Meliaceae and Rutaceae families. In the present study, rapid identification of limonoids from Cipadessa baccifera and Xylocarpus granatum were achieved using fast and simple electrospray ionization quadruple time-of-flight mass spectrometry (ESI-Q-ToF-MS/MS) in positive-ion mode. Although the structures of these compounds were found to be similar, Collision Induced Dissociation (CID) mass spectrometric analysis of these protonated/sodiated molecules indicated different fragmentation patterns by which the structures were confirmed. The fragment ions were formed due to the loss of neutral components like H 2 O, CO 2 , methanol, as well as McLafferty rearrangement and Retro-ene reaction. Furthermore, MS/MS spectra revealed different fragmentation pathways for different classes of limonoids which further aided dereplication., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A new series of Schizandrin (1) derivatives were synthesized utilizing the C-9 position of the Schizandrin core and evaluated for their cytotoxic activities against HeLa (cervical cancer), A549 (lung cancer), MCF-7 (breast cancer) and DU-145 (prostate cancer) cell lines. Among the synthesized series, 4e, 4f, 4g and 5 showed potent activities against tested cell lines. More significantly, compound 5 exhibited most potent cytotoxic activity against DU-145 with an IC 50 value of 1.38 μM which is comparable to the standard agent, doxorubicin. Further, flow cytometry analysis indicated that 5 arrested cells in G2/M phase and consequently leading to apoptosis. Molecular docking analysis showed that 5 occupied the colchicine binding pocket of tubulin. Overall, the present study demonstrates that 5, as a mitotic-agent., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Epoxyazadiradione (1), a major compound derived from Neem oil, showed modest anti-plasmodial activity against CQ-resistant and CQ-sensitive strains of the most virulent human malaria parasite P. falciparum. A series of analogues were synthesized by modification of the key structural moieties of this high yield natural product. Out of the library of all compounds tested, compounds 3c and 3g have showed modest anti-plasmodial activity against CQ-sensitive (IC 50 2.8 ± 0.29 μM and 1.5 ± 0.01 μM) and CQ-resistant strains (IC 50 1.3 ± 1.08 μM and 1.2 ± 0.14), while compounds 3k, 3l and 3m showed modest activity against CQ-sensitive strain of P. falciparum with IC 50 values of 2.3 ± 0.4 μM, 2.9 ± 0.1 μM and 1.7 ± 0.06 μM, respectively. Additionally, cytotoxic properties of these derivatives against SIHA, PANC 1, MDA-MB-231, and IMR-3 cancer cell lines were also studied and the results indicated that low cytotoxic potentials of all the derivatives which indicating the high selectivity index of the compounds., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

A comprehensive reinvestigation of chemical constituents from CHCl 3 -soluble extract of Cipadessa baccifera led to the isolation of two new limonoids 1, 2 together with six known compounds 3-8. Their structures were established on the basis of extensive analysis of spectroscopic (IR, MS, 2D NMR) data. Further, a series of cipaferen G (3) derivatives were efficiently synthesized utilizing Yamaguchi esterification (2, 4, 6-trichlorobenzoyl chloride, Et 3 N, THF, DMAP, toluene) at the C-3 position of the limonoids core, which is being reported for the first time. The anti-proliferative activity of the isolates and the synthetic analogues were studied against HeLa, PANC 1, HepG2, SKNSH, MDA-MB-231 and IMR32 cancer cells using the sulphorodamine B assay. Among the tested compounds, 13d and 13h manifested potent activity against IMR32, HepG2 cell lines with GI 50 0.013 and 0.01μM, respectively., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Several 2-anilino-3-aroylquinolines were designed, synthesized, and screened for their cytotoxic activity against five human cancer cell lines: HeLa, DU-145, A549, MDA-MB-231, and MCF-7. Their IC50 values ranged from 0.77 to 23.6 μm. Among the series, compounds 7 f [(4-fluorophenyl)(2-((4-fluorophenyl)amino)quinolin-3-yl)methanone] and 7 g [(4-chlorophenyl)(2-((4-fluorophenyl)amino)quinolin-3-yl)methanone] showed remarkable antiproliferative activity against human lung cancer and prostate cancer cell lines. The IC50 values for inhibiting tubulin polymerization were 2.24 and 2.10 μm for compounds 7 f and 7 g, respectively, and were much lower than that of the reference compound E7010 [N-(2-(4-hydroxyphenylamino)pyridin-3-yl)-4-methoxybenzenesulfonamide]. Furthermore, flow cytometric analysis revealed that these compounds arrest the cell cycle at the G2 /M phase, leading to apoptosis. Apoptosis was also confirmed by mitochondrial membrane potential, Annexin V-FITC assay, and intracellular ROS generation. Immunohistochemistry, western blot, and tubulin polymerization assays showed that these compounds disrupt tubulin polymerization. Molecular docking studies revealed that these compounds bind efficiently to β-tubulin at the colchicine binding site., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new class of combretastatin linked 1,3,4-oxadiazoles were designed, synthesized and screened for their cytotoxic activity against five human cancer cell lines such as HeLa, DU-145, A549, MDA-MB-231 and B16. These compounds showed significant cytotoxicity with IC50 values in the range 0.118-54.32μM. Conjugate 5m displayed potent antiproliferative activity against DU-145 cell line. Flow cytometric analysis revealed that these compounds arrested the cell cycle in G2/M phase. Moreover, the tubulin polymerization assay and immunofluorescence analysis indicate that 5m exhibits potent inhibitory effect on the tubulin assembly. Further, DNA fragmentation and Hoecst staining assays confirm that 5m induces apoptosis. Molecular docking studies and competitive binding assay indicated that 5m effectively bind at the colchicine binding site of the tubulin., (Copyright © 2016 Elsevier Inc. All rights reserved.)

A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed and validated for the determination of piperine (PPR) on dried blood spots (DBS). DBS samples were prepared by spiking the whole blood with analyte to produce 30 µL of blood spots on specimen collection cards. Chromatographic separation was achieved on an Atlantis dC 18 column using acetonitrile and water (0.1% formic acid) (85:15, v/v) as mobile phase in an isocratic mode of elution at a flow rate of 0.75 mL/min. MS detection was carried out in electrospray positive ion mode for the target ions and monitored at m/z 286.1465 for PPR and 272.1303 for the internal standard (IS). The developed method exhibited a linear dynamic range over 0.01-2000 ng/mL for PPR on DBS. The overall extraction recovery of PPR from DBS was 92.5%. Influence of hematocrit and spot volume on DBS was also evaluated and found to be well within the acceptable limits. The method was successfully applied to pharmacokinetic studies of PPR in rats.

Antibiotics are commonly used in the management of respiratory disorders such as cystic fibrosis (CF), non-CF bronchiectasis, asthma and COPD. In those conditions long-term antibiotics can be delivered as nebulised aerosols or administered orally. In CF, nebulised colomycin or tobramycin improve lung function, reduce number of exacerbations and improve quality of life (QoL). Oral antibiotics, such as macrolides, have acquired wide use not only as anti-microbial agents but also due to their anti-inflammatory and pro-kinetic properties. In CF, macrolides such as azithromycin have been shown to improve the lung function and reduce frequency of infective exacerbations. Similarly macrolides have been shown to have some benefits in COPD including reduction in a number of exacerbations. In asthma, macrolides have been reported to improve some subjective parameters, bronchial hyperresponsiveness and airway inflammation; however have no benefits on lung function or overall asthma control. Macrolides have also been used with beneficial effects in less common disorders such as diffuse panbronchiolitis or post-transplant bronchiolitis obliterans syndrome. In this review we describe our current knowledge the use of long-term antibiotics in conditions such as CF, non-CF bronchiectasis, asthma and COPD together with up-to-date clinical and scientific evidence to support our understanding of the use of antibiotics in those conditions., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Free radical scavenging and advanced glycation end-product (AGE) inhibitory potential were evaluated in the crude methanol extract of Dichrostachys cinerea. Bioassay-guided isolation led to the identification of four flavan-3-ols, namely (-)-mesquitol (1), oritin (2), (-)-festidinol (3) and (-)-epicatechin (4). Analysis of structure-activity relationships revealed that the presence of 7,8-dihydroxyl groups in the A-ring of flavan-3-ols in conjunction with 3',4'-dihydroxyls in the B-ring (1) is an important criterion for displaying potent AGE inhibitory activity along with free radical scavenging properties. (-)-Mesquitol (1), oritin (2), and (-)-festidinol (3) were found to be new natural AGE inhibitors. (-)-Mesquitol (1) displayed the most potent AGE inhibitory activity. Results suggest that (-)-mesquitol (1) may serve as an important natural organic lead compound for future development of antiglycating agents along with potent antioxidant activity.

The vapor-phase toxicity of Derris scandens Benth.-derived constituents was evaluated against four stored-product pests ( Callosobruchus chinensis L., Sitophilus oryzae L., Rhyzopertha dominica L., and Tribolium castaneum H.) using fumigation bioassays and compared to those of commonly used insecticides. The structures of all constituents of were characterized by spectroscopic analyses [nuclear magnetic resonance (NMR) and mass spectrometry]. The sensitivity of the test insect to compounds varied with exposure time, concentration, and insect species. Over 100% mortality after 24 h was achieved with the compounds osajin (2), scandinone (5), sphaerobioside (8), and genistein (9) against all of the test insects, while laxifolin (3) and lupalbigenin (4) showed 100% mortality after 72 h against T. csataneum and R. dominica . Scandenone (1), scandenin A (6), and scandenin (7) were less effective. Among the insects, C. chinensis , S. oryzae , and R. dominica were more susceptible to the treatments, whereas T. castaneum was less susceptible. The results of fumigation tests indicated that compounds from D. scandens whole plant extract are potential candidates to control stored-product pests.

The methanolic extract of rhizome of Himalayan rhubarb Rheum emodi displayed mild yeast as well as mammalian intestinal alpha-glucosidase inhibitory activity. However, further fractionation of active extract led to the isolation of several potent molecules in excellent yields, displaying varying degrees of inhibition on two test models of alpha-glucosidase. Rhapontigenin, desoxyrhapontigenin, chrysophanol-8-O-beta-d-glucopyranoside, torachrysone-8-O-beta-d-glucopyranoside displayed potent yeast alpha-glucosidase inhibition. However chrysophanol-8-O-beta-d-glucopyranoside, desoxyrhaponticin and torachrysone-8-O-beta-d-glucopyranoside displayed potent to moderate mammalian alpha-glucosidase inhibitory activity. Other compounds displayed mild activity on both the tests. Except desoxyrhapontigenin and rhapontigenin that increased Vmax, other compounds including crude extract decreased the Vmax significantly (p<0.02) in yeast alpha-glucosidase test. Further kinetic analysis on mammalian alpha-glucosidase inhibition showed that chrysophanol-8-O-beta-d-glucopyranoside, desoxyrhaponticin and torachrysone-8-O-beta-d-glucopyranoside may be classified as mixed-noncompetitive inhibitors. However, desoxyrhapontigenin and rhapontigenin may be classified as modulators of enzyme activity. Presence and position of glycoside moiety in compounds appear important for better inhibition of mammalian alpha-glucosidase. This is the first report assigning particularly, mammalian intestinal alpha-glucosidase inhibitory activity to these compounds. Chrysophanol-8-O-beta-d-glucopyranoside, desoxyrhaponticin, desoxyrhapontigenin and rhapontigenin have been isolated in substantial yields from R. emodi for the first time. Therefore, these compounds may have value in the treatment and prevention of hyperglycemia associated diabetes mellitus.