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Folk experiences suggest natural products in Tetradium ruticarpum can be effective inhibitors towards diabetes-related enzymes. The compounds were experimentally isolated, structurally elucidated, and tested in vitro for their inhibition effects on tyrosine phosphatase 1B (PTP1B) and α-glucosidase (3W37). Density functional theory and molecular docking techniques were utilized as computational methods to predict the stability of the ligands and simulate interaction between the studied inhibitory agents and the targeted proteins. Structural elucidation identifies two natural products: 2-heptyl-1-methylquinolin-4-one (1) and 3-[4-(4-methylhydroxy-2-butenyloxy)-phenyl]-2-propenol (2). In vitro study shows that the compounds (1 and 2) possess high potentiality for the inhibition of PTP1B (IC50 values of 24.3 ± 0.8, and 47.7 ± 1.1 μM) and α-glucosidase (IC50 values of 92.1 ± 0.8, and 167.4 ± 0.4 μM). DS values and the number of interactions obtained from docking simulation highly correlate with the experimental results yielded. Furthermore, in-depth analyses of the structure–activity relationship suggest significant contributions of amino acids Arg254 and Arg676 to the conformational distortion of PTP1B and 3W37 structures overall, thus leading to the deterioration of their enzymatic activity observed in assay-based experiments. This study encourages further investigations either to develop appropriate alternatives for diabetes treatment or to verify the role of amino acids Arg254 and Arg676.

Curcuma sahuynhensis Škorničk. & N.S. Lý has been discovered recently whose antiviral potential is unknown, thus deserved for discovery-phase screening. A combination of experimental characterization, quantum calculation, molecular docking simulation, physicochemical analysis, and absorption, distribution, metabolism, excretion, and toxicity (ADMET) was designed for the theoretical argument on the potentiality of oil-based components (1−27) against H5 hemagglutinin in influenza A virus (PDB-5E32), wild-variant SARS-CoV-2 main protease (PDB-6LU7), and SARS-CoV-2 Omicron spike protein (PDB-7T9J). Theoretical arguments based on various computational platforms specify the most promising bio-inhibitors, i.e. 23 (bio-compatibility: ground energy −966.73 a.u., dipole moment 3.708 Debye; bio-inhibitability: DS̅\bar{{\rm{DS}}} −12.5 kcal mol−1; drug-likeness: mass 304.7 amu, log P 1.31; polar-interactability: polarizability 32.8 Å3) and 26 (bio-compatibility: ground energy −1393.66109 a.u., dipole moment 5.087 Debye; bio-inhibitability: DS̅\bar{{\rm{DS}}} −11.9 kcal mol−1; drug-likeness: mass 437.5 amu, log P 4.28; polar-interactability: polarizability 45.7 Å3). The pkCSM-ADMET model confirms their favorable pharmacokinetics and pharmacology. The total essence is unsuitable for use as an antiviral source in its pure form since the most bioactive candidates are accountable for the small content. Particularly, 23 (7β-hydroxydehydroepiandrosterone) and 26 (ethyl cholate) are recommended for further experimental efforts of isolation and bioassaying trials.

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Objectives : To investigate the phytochemical constituents of Vietnamese Dalbergia oliveri and their inhibition of NO production. Methods : The ethyl acetate soluble fraction was subjected to column chromatography using silica gel and Sephadex LH-20 to isolate compounds. The chemical structures of isolated compounds were identified by nuclear magnetic resonance data and comparison with previously reported literature. The anti-inflammation effects of the isolated compounds on the lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells were measured using the Griess reaction. Results : Nine secondary metabolites ( 1 − 9 ) were isolated successfully from the heartwood of D. oliveri . The chemical structures of these compounds were identified as daidzein ( 1 ), formononetin ( 2 ), 3,7-dihydroxy-4 ′ -methoxyflavone ( 3 ), liquiritigenin ( 4 ), 3 ′ -methoxydaidzein ( 5 ), dalbergin ( 6 ), butin ( 7 ), sativanone ( 8 ), and isoliquiritigenin ( 9 ). This is the first time that compounds 1 , 3 , 5 − 8 have been isolated from D. oliveri . In the NO production inhibition, compounds 7 and 9 exhibited the most potent inhibitory activity, with IC 50 values of 7.6 and 11.2 μM, respectively, followed by 3 − 6 , with IC 50 values from 19.6 to 28.7 μM. Conclusion : The results suggested that D. oliveri and its natural products might exert anti-inflammatory effects due to their NO-inhibiting actions.

The increasing installation of Renewable Energy Sources (RES) presents significant challenges to the stability and reliability of power systems. This paper introduces an advanced control method to mitigate the adverse effects of intermittent generation from RES on the power system frequency stability. The proposed approach emphasizes the critical role of Battery Energy Storage Systems (BESS) and RES in enhancing the resilience of modern power networks. The Generation Export Management Schemes (GEMS) are employed to curtail the excessive export of RES, thereby contributing to improved frequency stability. This research involves a comprehensive analysis of the dynamic behavior of the network under various operational scenarios, particularly focusing on power exchanges between RES, BESS, and synchronous generation units. Furthermore, this paper focuses on the economic implications of integrating RES into the grid, with a detailed cost of balancing (COB) modelling and analysis conducted to assess the financial viability of the proposed frequency management solutions. The analysis encompasses both short-term and long-term perspectives, providing insights into the development of economically sustainable smart power networks that effectively integrate renewable energy and storage technologies while maintaining system stability. [ABSTRACT FROM AUTHOR]

A study on the phytochemical composition of the roots of Polygonum multiflorum collecting in Vietnam and an evaluation of its capacity to inhibit pancreatic lipase enzyme was conducted. In total, 12 metabolites (1 – 12) were isolated from anti-lipase activity-guided fractionation of P. multiflorum. The isolated compounds (1 – 12) were identified as trans -resveratrol (1), methyl protocatechuate (2), methyl gallate (3), catechin (4), epicatechin (5), myrciaphenone A (6), quercetin (7), kaempferol (8), apigenin (9), luteolin (10), tricin (11), and afzelin (12). This is the first time Compound 12 has been reported from P. multiflorum. However, 12 second metabolites (1 – 12) were tested in vitro to assess the anti-lipase potential. The results revealed Compound 7 exhibited the most significant lipase inhibition, with an IC50 value of 0.30 ± 0.04 μM. Following closely, Compounds 6, 8, 10, and 12 displayed IC50 values of 5.38 ± 0.65, 0.72 ± 0.10, 0.79 ± 0.19, and 1.22 ± 0.18 μM, respectively. For comparison, orlistat (positive control), the most common anti-obesity drug available on the market, has an IC50 value of 0.91 ± 0.10 μM. Molecular docking was applied to explore the affinity and interactions between active compounds 6 – 8, 10, and 12 and proteins associated with obesity, namely pancreatic lipase–colipase complex (PLCC) and pancreatic lipase-related protein 1 (PLRP1). In addition, absorption, distribution, metabolism, excretion, and toxicity (ADMET) were used in predictions. The results indicate that the active compounds isolated from P. multiflorum could be further in-depth research on lipase inhibition. [ABSTRACT FROM AUTHOR]

Objective: The Knema genus contains various naturally occurring secondary metabolites with pharmacological potential, including antitumor, neuroprotective, antidiabetic, and hepatoprotective activities. This study focuses on identifying nitric oxide production inhibitors from Vietnamese Knema globularia. Methods: The secondary metabolites were isolated using several chromatographic techniques. Their chemical structures were determined using nuclear magnetic resonance (NMR) spectroscopy and compared with published literature. The anti-inflammatory effect was evaluated using the Griess assay, and protein interactions were investigated through docking studies. Results: Based on their anti-inflammatory activity, six compounds (1-6) were isolated from Vietnamese K. globularia. These compounds were identified as lupeol (1), formononetin (2), isoliquiritigenin (3), 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]propane-1,3-diol (4), (+)-catechin (5), and (−)-epicatechin (6). For the first time, compounds 1, 3, and 4 were reported from Vietnamese K. globularia. All isolated compounds were tested against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW264.7 cells to assess their anti-inflammatory potential. Compound 5 exhibited the highest inhibitory activity, with an IC50 value of 5.61 μM, followed by compounds 3 and 6, with IC50 values of 6.76 and 11.52 μM, respectively. However, compounds 1, 2, and 4 showed inactivity with IC50 values exceeding 30 μM. Molecular docking was then employed to investigate the affinity and interactions between compounds 3, 5, and 6 and proteins involved in inflammation, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and interleukin-8 (IL-8), along with ADMET (absorption, distribution, metabolism, excretion, and toxicity) predictions. Conclusion: These findings suggest that the active constituents derived from Vietnamese K. globularia have the potential as anti-inflammatory agents worthy of further exploration and development. [ABSTRACT FROM AUTHOR]

Objective: Aruncus dioicus has been known by the scientific literature and folk experiences for its diverse biological activities, including anti-hyperglycemic effects. Methodology: The aerial parts of the plant collected from Quan Lan Island (Vietnam) were subjected to a methodical theory-experiment investigation for its chemical composition and biological potentials. Results: Firstly, experimental isolation and spectroscopic characterization identified the compositional compounds, ie sambunigrin (1), prunasin (2), uridine (3), and adenosine (4). Secondly, their elucidated structures were predicted with promising bio-chemo-pharmacological potentiality by different computational platforms, ie: docking simulation (docking scores < 10 kcal.mol−1); quantum calculation (dipole moments < 3 Debye); QSARIS model (satisfying Lipinski's rule of five); SwissADME model (satisfying Pires’ interpretations). Finally, the compounds (1-4) were under accumulative purification and in vitro tests against diabetes-related enzymes, ie: protein tyrosine phosphatase 1B (1 with lowest IC50 value 0.39 ± 0.26 μM, 2 with no activity) and α-glucosidase (1 with lowest IC50 value 44.89 ± 0.93 μM, 2 with no activity); also, the inhibitory kinetics based on Lineweaver-Burk and Dixon plot experiments revealed the competitive inhibition mode of 1 against PTP1B (Ki value 0.49 μM). Conclusions: Altogether, the results obtained suggest that A. dioicus and its bioactive compounds, especially sambunigrin (1), uridine (3), and adenosine (4), could be considered as a natural source for further research and development of anti-diabetic agents. [ABSTRACT FROM AUTHOR]

Seven metabolites (1 – 7) were isolated from the Vietnamese Scutellaria indica, guided by anti-inflammatory activity. The identified compounds comprise scrocaffeside A (1), naringenin-7-O-glucoside (2), darendoside B (3), decaffeoylverbascoside (4), plantainoside C (5), acteoside (6), and isoacteoside (7). This is the first time the compounds 1 – 3 and 5 were isolated from the entire Scutellaria indica. Compounds 1 – 7 tested for their anti-inflammatory potential by inhibiting nitric oxide (NO) production. Compound 1 showed the most activity (IC50 = 31.4 μM), followed by compounds 2, 4, 6, and 7 exhibited IC50 values of 41.2, 87.4, 52.2, and 44.6 μM, respectively. However, compounds 3 and 5 were inactive (IC50 > 100 μM). Molecular docking was applied to study the affinity and interactions between compound 1 and inflammatory-caused proteins based on the in vitro results. Compound 1 generated the lowest binding free energy with the cyclooxygenase-2 (COX-2) target, which was −9.8 kcal/mol, followed by inducible nitric oxide synthase (iNOS, –8.4 kcal/mol), and interleukin-8 (IL-8, –7.6 kcal/mol). The results indicate that compound 1 derived from S. indica has the potential to be further explored and developed as an inflammatory inhibitor. [ABSTRACT FROM AUTHOR]