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Melicope glabra­ (Blume) T. G. Hartley is a plant of Rutaceae family. The present study aimed to evaluate the in vivo hypoglycemic effect of M. glabra leaves extract on diabetic rats and identify its bioactive components. The induction of diabetes in Sprague-Dawley rats was done by a combination of high-fat diet and low-dose streptozotocin injection. The M. glabra extracts and standard sitagliptin were orally administered once daily to the diabetic rats for 28 days. The diabetic rats showed drastic weight loss, hyperglycemia, poor glucose tolerance, hyperlipidemia, and disturbances in the liver and kidney functions. However, oral administration of M. glabra extracts to the diabetic rats significantly lowered the DPP-4 level and increased glucagon-like peptide-1 (GLP-1) level. Scopoletin, pachypodol, and stigmasterol were revealed as the active DPP-4 and α-amylase inhibitors. This study revealed novel findings which suggest the

Melicope latifolia (DC.) T. G. Hartley (Rutaceae) was reported to contain various phytochemicals including coumarins, flavonoids, and acetophenones. This study investigates the antidiabetic and antioxidant effects of M. latifolia bark extracts, fractions, and isolated constituents. Melicope latifolia extracts (hexane, chloroform, and methanol), fractions, and isolated constituents with varying concentrations (0.078–10 mg/mL) were subjected to in vitro α-amylase and dipeptidyl peptidase-4 (DPP-4) inhibitory assay. Molecular docking was performed to study the binding mechanism of active compounds towards α-amylase and DPP-4 enzymes. The antioxidant activity of M. latifolia fractions and compounds were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and β-carotene bleaching assays. Melicope latifolia chloroform extract showed the highest antidiabetic activity (α-amylase IC50: 1464.32 μg/mL; DPP-4 IC50: 221.58 μg/mL). Fractionation of chloroform extract yielded four major fractions (CF1–CF4) whereby CF3 showed the highest antidiabetic activity (α-amylase IC50: 397.68 μg/mL; DPP-4 IC50: 37.16 μg/mL) and resulted in β-sitosterol (1), halfordin (2), methyl p-coumarate (3), and protocatechuic acid (4). Isolation of compounds 2–4 from the species and their DPP-4 inhibitory were reported for the first time. Compound 2 showed the highest α-amylase (IC50: 197.53 μM) and β-carotene (88.48%) inhibition, and formed the highest number of molecular interactions with critical amino acid residues of α-amylase. The highest DPP-4 inhibition was exhibited by compound 3 (IC50: 911.44 μM). The in vitro and in silico analyses indicated the potential of M. latifolia as an alternative source of α-amylase and DPP-4 inhibitors. Further pharmacological studies on the compounds are recommended.

This study aims to develop a controlled release oil palm empty fruit bunch hemicellulose (EFB-H) inhibitor tablet for mild steel in 1 M HCl. As plant extracts tend to deteriorate at longer immersion time, limiting its industrial applicability, we attempted to lengthen the inhibition time by forming a controlled release inhibitor tablet. Electrochemical methods (potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS)) were employed to investigate the efficiency and mechanism of the inhibition. An optimum dosage and immersion time was determined via Response Surface Methodology (RSM). EFB-H tablet was formulated using D-optimal mixture design, and its anticorrosion action at extended immersion time was compared with EFB-H powder. PDP measurement revealed that EFB-H is a mixed type inhibitor. RSM optimization unveiled that the optimum point for a maximum inhibition efficiency (87.11%) was at 0.33 g of EFB-H and 120 h of immersion time. Tablet T3 with EFB-H to gum Arabic to hydroxypropyl methylcellulose ratio of 66:0:34 portrayed the best tensile strength (0.243 MPa), disintegration time (152 min) and dissolution behavior. EFB-H tablet exhibited a longer-lasting inhibition effect than powder, which was 360 h as compared to 120 h for powder. Overall, EFB-H tablet has been successfully developed, and its enhanced effective inhibition time has been experimentally proven.

Curculigo is a potent plant with a variety of traditional uses, such as anti-oxidant, anti-diabetic, anti-tumor, anti-bacterial, anti-cancer, anti-osteoporosis, and wound-healing. The comprehensive profiling of the Curculigolatifolia metabolome was carried out by generating a molecular network (MN) from Liquid Chromatography–Tandem Mass Spectrometry (LC-MS/MS) data to profile the methanol extract and correlating them with their antioxidant (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), total phenolic contents (TPC), and β-carotene) and antimicrobial (disk-diffusion agar method, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC)) properties. The antioxidant capacity was observed to be significantly higher in the rhizome crude extract, with 18.10 ± 0.91 µg/mL DPPH activity, and a β-carotene bleaching result of 35.20%. For the antimicrobial activity, the leaf crude extract exhibited a strong Staphylococcus aureus and Salmonella choleraesuis (8–15 ± 3.0 mm) inhibition in the disk-diffusion agar. The leaf extract also exhibited maximum antibacterial activity against S. aureus (MIC = ±0.25 mg/mL, MBC = ±0.25 mg/mL) and S. choleraesuis (MIC = ±0.25 mg/mL, MBC = ±0.25 mg/mL). LC-MS/MS analysis and MN revealed norlignans and phenolic glycosides as major metabolites in the rhizome and leaf extracts of the negative mode (M − H)−. Fourteen known compounds were identified, and three unknown compounds were putatively identified in the rhizome extract, while ten known compounds and six unknown compounds were putatively identified in the leaf extract.

In this study, Kraft lignin was esterified with phthalic anhydride and was served as reinforcing filler for poly(butylene succinate) (PBS). Composites with different ratios of PBS, lignin (L), modified lignin (ML) and kenaf core fibers (KCF) were fabricated using a compounding method. The fabricated PBS composites and its counterparts were tested for thermal, physical and mechanical properties. Weight percent gain of 4.5% after lignin modification and the FTIR spectra has confirmed the occurrence of an esterification reaction. Better thermo-mechanical properties were observed in the PBS composites reinforced with modified lignin and KCF, as higher storage modulus and loss modulus were recorded using dynamic mechanical analysis. The density of the composites fabricated ranged from 1.26 to 1.43 g/cm3. Water absorption of the composites with the addition of modified lignin is higher than that of composites with unmodified lignin. Pure PBS exhibited the highest tensile strength of 18.62 MPa. Incorporation of lignin and KCF into PBS resulted in different extents of reduction in tensile strength (15.78 to 18.60 MPa). However, PBS composite reinforced with modified lignin exhibited better tensile and flexural strength compared to its unmodified lignin counterpart. PBS composite reinforced with 30 wt% ML and 20 wt% KCF had the highest Izod impact, as fibers could diverge the cracking propagation of the matrix. The thermal conductivity value of the composites ranged from 0.0903 to 0.0983 W/mK, showing great potential as a heat insulator.

Phytochemical study on the stem bark of Clausena excavata Burm. f. led to the isolation and identification of 11 compounds, including four prenylated coumarins (1–4), three carbazole alkaloids (5–7), a limonoid (8), a sterol (9), a depside (10) and a xanthone (11). The chemical structures of the compounds were elucidated based on NMR and mass spectroscopic data, and further supported by comparison with previously literature values. This is the first report on the isolation of compounds 10 and 11 from the genus Clausena. The chemotaxonomic significance of the isolated compounds is discussed.

The application of preparative thin layer chromatography-2,2-diphenyl-1-picrylhydrazyl (PTLC-DPPH) bioautography technique successfully isolated a lignan sesamin (1), two prenylated coumarins (2 and 3) and a marmesin glycosides (4) from Micromelum minutum methanol bark extract. Compounds 2 and 3 were identified as new compounds whereas 1 and 4 were first isolated from Micromelum genus. Structural identification of all compounds were done by detailed spectroscopic analyses and comparison with literature data. Antioxidant capacities of extract, active fraction and compounds were measured based on DPPH free radical savenging activity, oxygen radical absorbance capacity (ORAC) and β-carotene bleaching. The DPPH activity of methanol extract and its fraction present the IC50 values of 54.3 and 168.9 µg/mL meanwhile the β-carotene bleaching results were 55.19% and 5.75% respectively. The ORAC measurements of M. minutum extract, compounds 2 and 4 showed potent antioxidant activity with the values of 5123, 5539 and 4031 µmol TE/g respectively.

Context: Paederia foetida L. (Rubiaceae) is an edible plant distributed in Asian countries including Malaysia. Fresh leaves have been traditionally used as a remedy for indigestion and diarrhea. Several phytochemical studies of the leaves have been documented, but there are few reports on twigs. Objective: This study investigates the enzyme inhibition of P. foetida twig extracts and compound isolated from them. In addition, in silico molecular docking of scopoletin was investigated. Materials and methods: Plants were obtained from two locations in Malaysia, Johor (PFJ) and Pahang (PFP). Hexane, chloroform and methanol extracts along with isolated compound (scopoletin) were evaluated for their enzyme inhibition activities (10,000–0.000016 µg/mL). The separation and identification of bio-active compounds were carried out using column chromatography and spectroscopic techniques, respectively. In silico molecular docking of scopoletin with receptors (α-amylase and α-glucosidase) was carried out using AutoDock 4.2. Results: The IC50 values of α-amylase and α-glucosidase inhibition activity of PFJ chloroform extract were 9.60 and 245.6 µg/mL, respectively. PFP chloroform extract exhibited α-amylase and α-glucosidase inhibition activity (IC50 = 14.83 and 257.2 µg/mL, respectively). The α-amylase and α-glucosidase inhibitory activity of scopoletin from both locations had IC50 values of 0.052 and 0.057 µM, respectively. Discussion and conclusions: Separation of PFJ chloroform extract afforded scopoletin (1), stigmasterol (2) and γ-sitosterol (3) and the PFP chloroform extract yielded (1), (2), (3) and ergost-5-en-3-ol (4). Scopoletin was isolated from this species for the first time. In silico calculations gave a binding energy between scopoletin and α-amylase of −6.03 kcal/mol.

Melicope glabra (Blume) T. G. Hartley from the Rutaceae family is one of the richest sources of plant secondary metabolites, including coumarins and flavanoids. This study investigates the free radical scavenging and antibacterial activities of M. glabra and its isolated compounds. M. glabra ethyl acetate and methanol extracts were prepared using the cold maceration technique. The isolation of compounds was performed with column chromatography. The free radical scavenging activity of the extracts and isolated compounds were evaluated based on their oxygen radical absorbance capacity (ORAC) activities. The extracts and compounds were also subjected to antibacterial evaluation using bio-autographic and minimal inhibitory concentration (MIC) techniques against two oral pathogens, Enterococcus faecalis and Streptococcus mutans. Isolation of phytoconstituents from ethyl acetate extract successfully yielded quercetin 3, 5, 3’-trimethyl ether (1) and kumatakenin (2), while the isolation of the methanol extract resulted in scoparone (3), 6, 7, 8-trimethoxycoumarin (4), marmesin (5), glabranin (6), umbelliferone (7), scopoletin (8), and sesamin (9). The study is the first to isolate compound (1) from Rutaceae plants, and also the first to report the isolation of compounds (2–5) from M. glabra. The ORAC evaluation showed that the methanol extract is stronger than the ethyl acetate extract, while umbelliferone (7) exhibited the highest ORAC value of 24 965 μmolTE/g followed by glabranin (6), sesamin (9) and scopoletin (8). Ethyl acetate extract showed stronger antibacterial activity towards E. faecalis and S. mutans than the methanol extract with MIC values of 4166.7 ± 1443.4 μg/ml and 8303.3 ± 360.8 μg/ml respectively. Ethyl acetate extract inhibited E. faecalis growth, as shown by the lowest optical density value of 0.046 at a concentration of 5.0 mg/mL with a percentage inhibition of 95%. Among the isolated compounds tested, umbelliferone (7) and sesamin (9) exhibited promising antibacterial activity against S. mutans with both exhibiting MIC values of 208.3 ± 90.6 μg/ml. Findings from this study suggests M. glabra as a natural source of potent antioxidant and antibacterial agents.

An undescribed conjugated sesquiterpene, amelicarin (

An undescribed conjugated sesquiterpene, amelicarin (1), together with nine known compounds (2–10) were isolated for the first time from Melicope latifolia. Their structures were elucidated by extensive NMR spectroscopic and mass spectrometric methods. The conjugated sesquiterpene possesses a unique 6/6/9/4-ring fused tetracyclic skeleton. The proposed biosynthesis pathway of 1 consist of three reactions steps: (1) polyketide formation, (2) cyclisation and (3) addition to form the conjugated sesquiterpenoid as final metabolite. Out of the ten isolated metabolites, amelicarin (1) showed activity against 4 cancerous cell lines namely SK-MEL skin cancer, KB oral cancer, BT-549 breast cancer, and SK-OV-3 ovarian cancer with IC50 values between 15 and 25 µg/mL.

Christia vespertilionis, commonly known as &lsquo, Daun Rerama&rsquo, has recently garnered attention from numerous sources in Malaysia as an alternative treatment. Its herbal decoction was believed to show anti-inflammatory and anti-cancer effects. The present study investigated the cytotoxicity of the extract of root and leaf of C. vespertilionis. The plant parts were successively extracted using the solvent maceration method. The most active extract was further fractionated to afford F1&ndash, F8. The cytotoxic effects were determined using MTT assay against human breast carcinoma cell lines (MCF-7 and MDA-MB-231). The total phenolic content (TPC) of the extracts were determined. The antioxidant properties of the extract were also studied using DPPH and &beta, carotene bleaching assays. The ethyl acetate root extract demonstrated selective cytotoxicity especially against MDA-MB-231 with the highest TPC and antioxidant properties compared to others (p &lt, 0.05). The TPC and antioxidant results suggest the contribution of phenolic compounds toward its antioxidant strength leading to significant cytotoxicity. F3 showed potent cytotoxic effects while F4 showed better antioxidative strength compared to others (p &lt, 0.05). Qualitative phytochemical screening of the most active fraction, F3, suggested the presence of flavonoids, coumarins and quinones to be responsible toward the cytotoxicity. The study showed the root extracts of C. vespertilionis to possess notable anti-breast cancer effects.

Clausenidin is a pyranocoumarin majorly found in medicinal herbs of the Rutaceae family used to treat cancer patients locally in Asia. The compound is presumed to have anti-cancer cell effect but its exact mechanism of action is still unknown. The study aimed to evaluate the effect of pure clausenidin on p53-mediated apoptosis as well as other cell death pathways in colon cancer (HT-29) cell lines. The anti-proliferative effect of clausenidin by cell cycle and annexin V assay using flow cytometry was evaluated. Morphological analysis of the treated cells was performed using scanning and transmission electron microscopy. Furthermore, the effect of p53 mRNA on cell cycle and apoptosis-related genes and proteins in clausenidin-treated HT-29 cells was investigated using qPCR and Western blot assays, respectively. Clausenidin induced a p53 dependent G0/G1 cell cycle arrest in HT-29 cells. It was also observed that the anti-cancer cell effect of clausenidin occurred via p53 mediated activation of p21, bax and transrepression of survivin and bcl 2 that culminated in the apoptosis of colon cancer cells. The transmission electron microscopy (TEM) micrographs confirmed the occurrence of apoptosis in clausenidin-treated HT-29 cells. Clausenidin is a potent anti-HT-29 cell agent that can be used to treat colon tumors. Key words: Clausenidin, p53, p21, apoptosis, cell cycle.

In this paper, antioxidant properties of Aegle marmelos (stem bark, leaves) and Murraya koenigii (stem bark, root) were evaluated by 2,2-diphenyl-1-picrylhydrazy (DPPH) free radical scavenging, 2,2’-Azino-bis(3-ethylbenzthiozoline-6-sulfonic acid) (ABTS) decolourisation, cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP) and linoleic acid/β-carotene assays. The chloroform extract of Murraya koenigii stem bark was found to possess the highest antioxidant activity in CUPRAC (1490.89 mgTE/g extract). In contrary, the hexane extract from Aegle marmelos leaves exhibited the weakest antioxidant activity in the DPPH assay (81.06 mgTE/g extract). The bioactive compound mahanimbine (7) isolated from the stem bark of Murraya koenigii was found to be the most active antioxidant agent with TEAC of 927.73 and 1649.31 mgTE/g corresponding to the ABTS and CUPRAC assays, respectively, as well as a good lipid peroxidation inhibitor with an inhibitory percentage of 70.95%. These CUPRAC and ABTS assays are the first report for Malaysian Murraya koenigii species.

Bambangan (Mangifera pajang) has been shown to exhibit anticancer activity. One of the major bioactive compounds present in the methanol extract of kernel of M. pajang is methyl 3,4,5- trihydroxybenzoate (methyl gallate). The present study was conducted to evaluate the cytotoxic activity of this compound against selected cancer cell lines such as hormone dependent breast cancer (MCF-7), non-hormone dependent breast cancer (MDA-MB-231), prostate cancer (PC-3), pancreatic cancer cell (CP-2) and colon cancer (HCT-116) cell lines. Methyl gallate was isolated from methanol extract by using column chromatography and the compound was further confirmed by using NMR, GC-MS analysis and comparison of spectral data of the isolated data with published report. The cytotoxicity of the compound was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay at concentrationsranging from 0 to 100 μM. The results showed that the compound only induced cytotoxicity in MCF-7 and PC-3 cell lines with IC50 values of 54.7 ± 4.73 and 97.6 ± 4.04 μM, respectively. Furthermore, Capan 2, MDA-MB-231 and HCT-116 showed no inhibition towards the cell proliferation after the treatment with compound (IC50 values more than100 μM). Thus, the compound isolated from kernel of M. pajang exhibited selective cytotoxic activity against selected cancer cell lines.

Paederia foetida L. (Rubiaceae) is a climber which is widely distributed in Asian countries including Malaysia. The plant is traditionally used to treat various diseases including diabetes. This study is to evaluate the enzymatic inhibition activity of Paederia foetida twigs extracts and to identify the metabolites responsible for the bioactivity by gas chromatography-mass spectrometry (GC-MS) metabolomics profiling. Three different twig extracts, namely, hexane (PFH), chloroform (PFC), and methanol (PFM), were submerged for their α-amylase and α-glucosidase inhibition potential in 5 replicates for each. Results obtained from the loading column scatter plot of orthogonal partial least square (OPLS) model revealed the presence of 12 bioactive compounds, namely, dl-α-tocopherol, n-hexadecanoic acid, 2-hexyl-1-decanol, stigmastanol, 2-nonadecanone, cholest-8(14)-en-3-ol, 4,4-dimethyl-, (3β,5α)-, stigmast-4-en-3-one, stigmasterol, 1-ethyl-1-tetradecyloxy-1-silacyclohexane, ɣ-sitosterol, stigmast-7-en-3-ol, (3β,5α,24S)-, and α-monostearin. In silico molecular docking was carried out using the crystal structure α-amylase (PDB ID: 4W93) and α-glucosidase (PDB ID: 3WY1). α-Amylase-n-hexadecanoic acid exhibited the lowest binding energy of -2.28 kcal/mol with two hydrogen bonds residue, namely, LYS178 and TYR174, along with hydrophobic interactions involving PRO140, TRP134, SER132, ASP135, and LYS172. The binding interactions of α-glucosidase-n-hexadecanoic acid complex ligand also showed the lowest binding energy among 5 major compounds with the energy value of -4.04 kcal/mol. The complex consists of one hydrogen bond interacting residue, ARG437, and hydrophobic interactions with ALA444, ASP141, GLN438, GLU432, GLY374, LEU373, LEU433, LYS352, PRO347, THR445, HIS348, and PRO351. The study provides informative data on the potential antidiabetic inhibitors identified in Paederia foetida twigs, indicating the plant has the therapeutic effect properties to manage diabetes.

Identification of honey origin based on specific chemical markers is important for honey authentication. This study is aimed to differentiate Malaysian stingless bee honey from different entomological origins (Heterotrigona bakeri, Geniotrigona thoracica and Tetrigona binghami) based on physicochemical properties (pH, moisture content, ash, total soluble solid and electrical conductivity) and volatile compound profiles. The discrimination pattern of 75 honey samples was observed using Principal Component Analysis (PCA), Hierarchical Clustering Analysis (HCA), Partial Least Square-Discriminant Analysis (PLS-DA), and Support Vector Machine (SVM). The profiles of H. bakeri and G. thoracica honey were close to each other, but clearly separated from T. binghami honey, consistent with their phylogenetic relationship. T. binghami honey is marked by significantly higher electrical conductivity, moisture and ash content, and high abundance of 2,6,6-trimethyl-1-cyclohexene-1-carboxaldehyde, 2,6,6-trimethyl-1-cyclohexene-1-acetaldehyde and ethyl 2-(5-methyl-5-vinyltetrahydrofuran-2-yl)propan-2-yl carbonate. Copaene was proposed as chemical marker for G. thoracica honey. The potential of different parameters that aid in honey authentication was highlighted.

Hyperlipidemia is defined as the presence of either hypertriglyceridemia or hypercholesterolemia, which could cause atherosclerosis. Although hyperlipidemia can be treated by hypolipidemic drugs, they are limited due to lack of effectiveness and safety. Previous studies demonstrated that xanthorrhizol (XNT) isolated from Curcuma xanthorrhizza Roxb. reduced the levels of free fatty acid and triglyceride in vivo. However, its ability to inhibit cholesterol uptake in HT29 colon cells and adipogenesis in 3T3-L1 cells are yet to be reported. In this study, XNT purified from centrifugal TLC demonstrated 98.3% purity, indicating it could be an alternative purification method. The IC50 values of XNT were 30.81 ± 0.78 μg/mL in HT29 cells and 35.07 ± 0.24 μg/mL in 3T3-L1 adipocytes, respectively. Cholesterol uptake inhibition study using HT29 colon cells showed that XNT (15 μg/mL) significantly inhibited the fluorescent cholesterol analogue NBD uptake by up to 27 ± 3.1% relative to control. On the other hand, higher concentration of XNT (50 μg/mL) significantly suppressed the growth of 3T3-L1 adipocytes (5.9 ± 0.58%) compared to 3T3-L1 preadipocytes (81.31 ± 0.55%). XNT was found to impede adipogenesis of 3T3-L1 adipocytes in a dose-dependent manner from 3.125 to 12.5 μg/mL, where 12.5 μg/mL significantly suppressed 36.13 ± 2.1% of lipid accumulation. We postulate that inhibition of cholesterol uptake, adipogenesis, preadipocyte and adipocyte number may be utilized as treatment modalities to reduce the prevalence of lipidemia. To conclude, XNT could be a potential hypolipidemic agent to improve cardiovascular health in the future.

Aglaia oligophylla Miq. is a shrub of approximately 25 meters tall under the Meliaceae family which possess distinct pharmacological properties including insecticides, anti-inflammatory and anticancer. The purpose of this study is to evaluate the antioxidant capacity of the trunks and stem of Aglaia oligophylla plant extracts and to isolate their chemical constituents. The antioxidant activity was evaluated as the reducing antioxidant capacity includes of cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) assays. In CUPRAC assay, ethyl acetate extract of the trunks part exhibited the strongest reducing capacity with the value of 1543 mg Trolox equivalent (TE)/g and for the stem part, methanol extract showed the strongest reducing antioxidant capacity with the value of 1059 mg TE/g. In FRAP assay, the methanol extracts of both trunks and stem of the plant showed the strongest reducing power with the values of 1269 mg TE/g and 1084 mg TE/g respectively. Repeated column chromatographic separation on chloroform extract of the trunks part afforded one triterpenes which was suggested to be stigmasterol (1) whilst the separation on methanol extract of the trunks obtained a triterpene, β-sitosterol (2). In the stem of A. oligophylla, the column chromatographic separation on petroleum ether extract afforded a new triterpene, namely oligophyllic acid (3) while the separation on chloroform and ethyl acetate extracts gave compound 2. All the chemical constituents were elucidated by comparison with literature review reported previously. Based on the value of CUPRAC and FRAP antioxidant assays of the plant extracts, A. oligophylla, shows great potential for the possibility of discovery and development of health promoting supplement from the extracts and chemical constituents.

Molecular dynamics (MD) simulation is a powerful tool to study the molecular level working mechanism of corrosion inhibitors in mitigating corrosion. In the past decades, MD simulation has emerged as an instrument to investigate the interactions at the interface between the inhibitor molecule and the metal surface. Combined with experimental measurement, theoretical examination from MD simulation delivers useful information on the adsorption ability and orientation of the molecule on the surface. It relates the microscopic characteristics to the macroscopic properties which enables researchers to develop high performance inhibitors. Although there has been vast growth in the number of studies that use molecular dynamic evaluation, there is still lack of comprehensive review specifically for corrosion inhibition of organic inhibitors on ferrous metal in acidic solution. Much uncertainty still exists on the approaches and steps in performing MD simulation for corrosion system. This paper reviews the basic principle of MD simulation along with methods, selection of parameters, expected result such as adsorption energy, binding energy and inhibitor orientation, and recent publications in corrosion inhibition studies.

The present study investigated the antidiabetic properties of the extracts and fractions from leaves and stem bark of M. glabra based on dipeptidyl peptidase-4 (DPP-4) and &alpha, amylase inhibitory activity assays. The chloroform extract of the leaves was found to be most active towards inhibition of DPP-4 and &alpha, amylase with IC50 of 169.40 &mu, g/mL and 303.64 &mu, g/mL, respectively. Bioassay-guided fractionation of the leaves&rsquo, chloroform extract revealed fraction 4 (CF4) as the most active fraction (DPP-4 IC50: 128.35 &mu, g/mL, &alpha, amylase IC50: 170.19 &mu, g/mL). LC-MS/MS investigation of CF4 led to the identification of trans-decursidinol (1), swermirin (2), methyl 3,4,5-trimethoxycinnamate (3), renifolin (4), 4&prime, 5,6,7-tetramethoxy-flavone (5), isorhamnetin (6), quercetagetin-3,4&prime, dimethyl ether (7), 5,3&prime, 4&prime, trihydroxy-6,7-dimethoxy-flavone (8), and 2-methoxy-5-acetoxy-fruranogermacr-1(10)-en-6-one (9) as the major components. The computational study suggested that (8) and (7) were the most potent DPP-4 and &alpha, amylase inhibitors based on their lower binding affinities and extensive interactions with critical amino acid residues of the respective enzymes. The binding affinity of (8) with DPP-4 (&minus, 8.1 kcal/mol) was comparable to that of sitagliptin (&minus, 8.6 kcal/mol) while the binding affinity of (7) with &alpha, amylase (&minus, 8.6 kcal/mol) was better than acarbose (&minus, 6.9 kcal/mol). These findings highlight the phytochemical profile and potential antidiabetic compounds from M. glabra that may work as an alternative treatment for diabetes.

The present study focused on the phytochemical profiling along with evaluation of in vitro antioxidant, α-glucosidase and α-amylase inhibitory activities of various crudes and fractions obtained from Lepisanthes fruticosa (Roxb) Leenh fruit. Ethanolic seed crude extract exhibited the strongest radical scavenging, β-carotene bleaching activity, α-glucosidase inhibition and the highest total phenolic content (TPC). Column chromatography afforded various fractions with fraction M4 being the most potent due to the strongest radical scavenging, β-carotene bleaching, α-glucosidase inhibition and greatest amount of TPC. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of ethanolic seed crude extract and fraction M4 showed the presence of various phytochemicals with antioxidant and antidiabetic properties, which include mostly flavonoids and tannins. The results may suggest that the ethanolic crude seed extract and its fraction could be an excellent source of bioactive phytochemicals with antioxidant and antidiabetic potential.

The study was performed to investigate the antioxidant capacities of Peperomia pellucida (L.) collected from two different locations using different solvents extraction. Antioxidant capacity was analyzed by 1, 1-Diphenyl-2-picryl hydrazyl (DPPH), β-carotene bleaching and oxygen radical absorbance capacity (ORAC) assays. The ability to scavenge free radical in DPPH assay showed that methanol extract of Penang (ground) sample depicted the highest value of 1108 ± 5.568 mg/ml compared to the other samples. In β-carotene bleaching assay, the ethyl acetate extract of Penang (ground) sample offered the highest percentage of scavenging activity from free radical (86.111%). In ORAC assay, methanol extract of Penang (ground) sample showed the highest value 397.691 μmol of Trolox equivalent/μl. Results between two locations showed no significant difference as compared to the samples from Selangor except for DPPH scavenging assay which depicted a highly significant difference (p

The nutritional value of the rhizomes of Kaempferia angustifolia was measured through the antioxidant properties of various extracts and the determination of the bioactive compounds. The chloroform and methanol extracts of the rhizomes of Kaempferia angustifolia showed strong free radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) with values of 615.92 mg Trolox equivalent (TE)/g each. The methanol extract also exhibited the strongest antioxidant properties in the azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) assay with a value of 38.87 mg TE/g. The hexane extract gave the strongest reducing ability in cupric reducing antioxidant capacity (CUPRAC) assay with a value of 901.76 mg TE/g, whilst the ethyl acetate extract exhibited the strongest reducing ability against ferric reducing antioxidant power (FRAP) with a value of 342.23 mg TE/g. Column chromatographic separation on the rhizomes of Kaempferia angustifolia afforded boesenboxide (1), crotepoxide (2), 2ˊ-hydroxy-4,4ˊ,6ˊ-trimethoxychalcone (3), kaempfolienol (4), and zeylenol (5), which were elucidated by spectroscopic methods. Kaempfolienol (4) was the strongest free radical agent against DPPH with a value of 443.92 mg TE/g, whilst 2ˊ-hydroxy-4,4ˊ,6ˊ-trimethoxychalcone (3) exhibited the strongest antioxidant properties with values of 42.23, 1497.22, and 781.53 mg TE/g against ABTS, CUPRAC, and FRAP assays, respectively.

Uridine-cytidine kinase 2 is an enzyme that is overexpressed in abnormal cell growth and its implication is considered a hallmark of cancer. Due to the selective expression of UCK2 in cancer cells, a selective inhibition of this key enzyme necessitates the discovery of its potential inhibitors for cancer chemotherapy. The present study was carried out to demonstrate the potentials of natural phytochemicals from the rhizome of Alpinia mutica to inhibit UCK2 useful for colorectal cancer. Here, we employed the used of in vitro to investigate the effectiveness of natural UCK2 inhibitors to cause HT-29 cell death. Extracts, flavokawain B, and alpinetin compound from the rhizome of Alpinia mutica was used in the study. The study demonstrated that the expression of UCK2 mRNA were substantially reduced in treated HT-29 cells. In addition, downregulation in expression of 18S ribosomal RNA was also observed in all treated HT-29 cells. This was confirmed by fluorescence imaging to measure the level of expression of 18S ribosomal RNA in live cell images. The study suggests the possibility of MDM2 protein was downregulated and its suppression subsequently activates the expression of p53 during inhibition of UCK2 enzyme. The expression of p53 is directly linked to a blockage of cell cycle progression at G0/G1 phase and upregulates Bax, cytochrome c, and caspase 3 while Bcl2 was deregulated. In this respect, apoptosis induction and DNA fragmentation were observed in treated HT-29 cells. Initial results from in vitro studies have shown the ability of the bioactive compounds of flavokawain B and alpinetin to target UCK2 enzyme specifically, inducing cell cycle arrest and subsequently leading to cancer cell death, possibly through interfering the MDM2-p53 signalling pathway. These phenomena have proven that the bioactive compounds could be useful for future therapeutic use in colon cancer.

Two new diprenylated dihydrochalcones, elastichalcone A 1 and elastichalcone B 2 and three known compounds were isolated from the leaves of Artocarpus elasticus. Their structures were determined by various spectroscopic techniques (UV, IR, MS, 1D-NMR and 2D-NMR). Elastichalcone B 2 and a known compound exhibited good free radical scavenging activity with IC50 values of 11.30 and 11.89 μg/ml, respectively.

Background Clausena excavata Burm.f. is a shrub traditionally used to treat cancer patients in Asia. The main bioactive chemical components of the plant are alkaloids and coumarins. In this study, we isolated clausenidin from the roots of C. excavata to determine its apoptotic effect on the colon cancer (HT-29) cell line. Method We examined the effect of clausenidin on cell viability, ROS generation, DNA fragmentation, mitochondrial membrane potential in HT-29 cells. Ultrastructural analysis was conducted for morphological evidence of apoptosis in the treated HT-29 cells. In addition, we also evaluated the effect of clausenidin treatment on the expression of caspase 3 and 9 genes and proteins in HT-29 cells. Result Clausenidin induced a G0/G1 cell cycle arrest in HT-29 cells with significant (p

Uridine-cytidine kinase 2 is implicated in uncontrolled proliferation of abnormal cells and it is a hallmark of cancer, therefore, there is need for effective inhibitors of this key enzyme. In this study, we employed the used of in silico studies to find effective UCK2 inhibitors of natural origin using bioinformatics tools. An in vitro kinase assay was established by measuring the amount of ADP production in the presence of ATP and 5-fluorouridine as a substrate. Molecular docking studies revealed an interesting ligand interaction with the UCK2 protein for both flavokawain B and alpinetin. Both compounds were found to reduce ADP production, possibly by inhibiting UCK2 activity in vitro. In conclusion, we have identified flavokawain B and alpinetin as potential natural UCK2 inhibitors as determined by their interactions with UCK2 protein using in silico molecular docking studies. This can provide information to identify lead candidates for further drug design and development.

Ethnopharmacological relevance Clausena excavata Burm. f . is used locally in folk medicine for the treatment of cancer in South East Asia. Aim of the study To determine the mechanism of action of pure clausenidin crystals in the induction of hepatocellular carcinoma (hepG2) cells apoptosis. Materials and methods Pure clausenidin was isolated from Clausena excavata Burm. f . and characterized using 1 H and 13 C NMR spectra. Clausenidin-induced cytotoxicity was determined by MTT assay. The morphology of hepG2 after treatment with clausenidin was determined by fluorescence and Scanning Electron Microscopy. The effect of clausenidin on the apoptotic genes and proteins were determined by real-time qPCR and protein array profiling, respectively. The involvement of the mitochondria in clausenidin-induced apoptosis was investigated using MMP, caspase 3 and 9 assays. Results Clausenidin induced significant (p Conclusion Clausenidin extracted from Clausena excavata Burm. f . is an anti-hepG2 cell compound as shown by its ability to induce apoptosis through the mitochondrial pathway of apoptosis. Clausenidin can potentially be developed into an anticancer compound.

The ethyl acetate and methanol bark extracts of Melicope glabra were evaluated for their antioxidant capacities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and β-carotene bleaching/linoleic acid system. Both extracts exhibited strong inhibition against the DPPH radical (IC50 values of 24.81 and 13.01 μg ml(-1), respectively) and strong antioxidant activity in β-carotene bleaching assay. Both samples were found to have high phenolic content with values of 39 and 44 mg GAE/g as indicated by Follin-Ciocalteau's reagent. Antioxidant TLC assay-guided isolation on the methanol extract led to the isolation of a new pyranocoumarin, glabranin (1), umbelliferone (2), scopoletin (3) and sesamin (4), and their structures were determined by spectroscopy. Compounds (1-3) showed significant activities on DPPH free radical with the IC50 of 240.20, 810.02 and 413.19 μg ml(-1), respectively. However, in β-carotene bleaching assay, sesamin (4) showed higher inhibitory activity (1 mg ml(-1), 95%) than glabranin (1) (1 mg ml(-1), 74%), whilst umbelliferone (2) and scopoletin (3) were slightly pro-oxidant.