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CONTEXT: Melicope latifolia (DC.) T. G. Hartley (Rutaceae) was reported to contain various phytochemicals including coumarins, flavonoids, and acetophenones. OBJECTIVE: This study investigates the antidiabetic and antioxidant effects of M. latifolia bark extracts, fractions, and isolated constituents. MATERIALS AND METHODS: 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 ß-carotene bleaching assays. RESULTS: 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 ß-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 ß-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). DISCUSSION AND CONCLUSIONS: 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.
Assuntos
Inibidores da Dipeptidil Peptidase IV/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rutaceae/química , alfa-Amilases/antagonistas & inibidores , Antioxidantes/química , Antioxidantes/farmacologia , Simulação por Computador , Dipeptidil Peptidase 4 , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Casca de Planta/química , Extratos Vegetais/isolamento & purificação , alfa-Amilases/químicaRESUMO
Scopoletin has previously been reported as a biomarker for the standardization of Paederia foetida twigs. This study is the first report on the determination and quantification of scopoletin using quantitative nuclear magnetic resonance (qNMR) in the different extracts of Paederia foetida twigs. The validated qNMR method showed a good linearity (r2 = 0.9999), limit of detection (LOD) (0.009 mg/mL), and quantification (LOQ) (0.029 mg/mL), together with high stability (relative standard deviation (RSD) = 0.022%), high precision (RSD < 1%), and good recovery (94.08-108.45%). The quantification results of scopoletin concentration in chloroform extract using qNMR and microplate ultraviolet-visible (UV-vis) spectrophotometer was almost comparable. Therefore, the qNMR method is deemed accurate and reliable for quality control of Paederia foetida and other medicinal plants without extensive sample preparation.
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Biomarcadores Farmacológicos/análise , Espectroscopia de Ressonância Magnética/métodos , Rubiaceae/química , Escopoletina/análise , Espectrofotometria Ultravioleta/métodos , Limite de Detecção , Extratos Vegetais/análise , Extratos Vegetais/química , Preparações de Plantas/análise , Plantas Medicinais/química , Sensibilidade e Especificidade , Solventes/químicaRESUMO
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 α-Amylase inhibitory activity assays. The chloroform extract of the leaves was found to be most active towards inhibition of DPP-4 and α-Amylase with IC50 of 169.40 µg/mL and 303.64 µg/mL, respectively. Bioassay-guided fractionation of the leaves' chloroform extract revealed fraction 4 (CF4) as the most active fraction (DPP-4 IC50: 128.35 µg/mL; α-Amylase IC50: 170.19 µg/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',5,6,7-tetramethoxy-flavone (5), isorhamnetin (6), quercetagetin-3,4'-dimethyl ether (7), 5,3',4'-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 α-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 (-8.1 kcal/mol) was comparable to that of sitagliptin (-8.6 kcal/mol) while the binding affinity of (7) with α-Amylase (-8.6 kcal/mol) was better than acarbose (-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.
Assuntos
Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/química , Inibidores de Glicosídeo Hidrolases/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Extratos Vegetais/química , Rutaceae/química , alfa-Amilases/química , Cromatografia Líquida , Inibidores da Dipeptidil Peptidase IV/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Compostos Fitoquímicos/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em TandemRESUMO
Christia vespertilionis, commonly known as 'Daun Rerama', 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-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 ß-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 < 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 < 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.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/patologia , Fabaceae/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Raízes de Plantas/química , Antioxidantes/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células , Feminino , Sequestradores de Radicais Livres/farmacologia , Humanos , Células Tumorais CultivadasRESUMO
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.
Assuntos
Hipoglicemiantes/farmacologia , Rubiaceae/química , alfa-Amilases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Malásia , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Escopoletina/isolamento & purificação , Escopoletina/farmacologia , alfa-Amilases/química , alfa-Amilases/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismoRESUMO
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.
Assuntos
Hipolipemiantes/isolamento & purificação , Hipolipemiantes/farmacologia , Fenóis/isolamento & purificação , Fenóis/farmacologia , Células 3T3-L1 , 4-Cloro-7-nitrobenzofurazano/análogos & derivados , 4-Cloro-7-nitrobenzofurazano/metabolismo , Animais , Centrifugação , Colesterol/análogos & derivados , Colesterol/metabolismo , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Células HT29 , Humanos , Hipolipemiantes/química , Espaço Intracelular/metabolismo , Camundongos , Fenóis/química , Coloração e RotulagemRESUMO
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 < 0.05) dose-dependent increase in apoptotic cell population. The DNA fragmentation assay also showed apoptotic features in the clausenidin-treated HT-29 cells. Clausenidin treatment had caused significant (p < 0.05) increases in the expression of caspase 9 protein and gene in HT-29 cells and mitochondrial ROS and mitochondrial membrane depolarization. The results suggest the involvement of the mitochondria in the caspase-dependent apoptosis in clausenidin-treated colon cancer cells. CONCLUSION: Clausenidin induces a caspase-dependent apoptosis in colon cancers through the stimulation of the mitochondria. The study demonstrates the potential of clausenidin for use in the treatment of colon cancers.
Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Clausena/química , Neoplasias do Colo/metabolismo , Extratos Vegetais/farmacologia , Piranocumarinas/farmacologia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Extratos Vegetais/química , Piranocumarinas/química , Espécies Reativas de Oxigênio/metabolismoRESUMO
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.
Assuntos
Inibidores Enzimáticos/química , Flavanonas/química , Flavonoides/química , Uridina Quinase/química , Difosfato de Adenosina/biossíntese , Alpinia/enzimologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Simulação por Computador , Inibidores Enzimáticos/uso terapêutico , Flavanonas/uso terapêutico , Flavonoides/uso terapêutico , Humanos , Ligantes , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Rizoma/enzimologia , Uridina Quinase/antagonistas & inibidoresRESUMO
Xanthorrhizol (XNT) is a bisabolane-type sesquiterpenoid compound extracted from Curcuma xanthorrhiza Roxb. It has been well established to possess a variety of biological activities such as anticancer, antimicrobial, anti-inflammatory, antioxidant, antihyperglycemic, antihypertensive, antiplatelet, nephroprotective, hepatoprotective, estrogenic and anti-estrogenic effects. Since many synthetic drugs possess toxic side effects and are unable to support the increasing prevalence of disease, there is significant interest in developing natural product as new therapeutics. XNT is a very potent natural bioactive compound that could fulfil the current need for new drug discovery. Despite its importance, a comprehensive review of XNT's pharmacological activities has not been published in the scientific literature to date. Here, the present review aims to summarize the available information in this area, focus on its anticancer properties and indicate the current status of the research. This helps to facilitate the understanding of XNT's pharmacological role in drug discovery, thus suggesting areas where further research is required.
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Stingless bee honey's nutritional value is gaining attention, but the impact of harvesting seasons, specifically the rainy (September 2018) and dry (February 2019) seasons in Malaysia on the honey's physicochemical properties and volatile compounds remains insufficiently explored. This research revealed marginal differences in the physicochemical properties between seasons. However, through individual bee species and cumulative data analysis, honey samples were effectively differentiated based on harvesting seasons. A set of seventeen volatile compounds were identified as potential chemical markers for distinguishing H. bakeri, G. thoracica, and T. binghami honey between rainy and dry seasons. For cumulative data, four significant markers were proposed. These discrimination methods and chemical markers can serve as valuable references in distinguishing stingless bee honey, whether its entomological origin is specified or not between rainy and dry seasons.
Assuntos
Mel , Abelhas , Animais , Mel/análise , Estações do Ano , Quimiometria , Máquina de Vetores de Suporte , MalásiaRESUMO
Type 2 Diabetes Mellitus accounts for 90% of most diabetes cases. Many commercial drugs used to treat this disease come with adverse side effects and eventually fail to restore glucose homeostasis. Therefore, an effective, economical and safe antidiabetic remedy from dietary source is considered. Taraxacum officinale (L.) Weber ex F.H.Wigg and Momordica charantia L. were chosen since both are used for centuries as traditional medicine to treat various ailments and diseases. In this study, the antidiabetic properties of a polyherbal combination of T. officinale and M. charantia ethanol extracts are evaluated. The bioactive solvent extracts of the samples selected from in vitro antidiabetic assays; α-amylase, α-glucosidase, and dipeptidyl peptidase-4 (DPP-4) inhibition, and glucose-uptake in L6 muscle cells were combined (1:1) to form the polyherbal combination. The antidiabetic efficacy of polyherbal combination was evaluated employing the above stated in vitro antidiabetic assays and in vivo oral glucose tolerance test and streptozotocin-nicotinamide (STZ-NA) induced diabetic rat model. A quadrupole time-of-flight liquid chromatography-mass spectrometry (Q-TOF LCMS) analysis was done to identify active compounds. The polyherbal combination exerted improved antidiabetic properties; increased DPP-4, α-amylase, and α-glucosidase inhibition. The polyherbal combination tested in vivo on diabetic rats showed optimum blood glucose-lowering activity comparable to that of Glibenclamide and Metformin. This study confirms the polyherbal combination of T. officinale and M. charantia to be rich in various bioactive compounds, which exhibited antidiabetic properties. Therefore, this polyherbal combination has the potential to be further developed as complex phytotherapeutic remedy for the treatment of Type 2 Diabetes Mellitus.
Assuntos
Hipoglicemiantes/farmacologia , Momordica charantia/química , Extratos Vegetais/farmacologia , Taraxacum/química , Animais , Glicemia/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Sinergismo Farmacológico , Teste de Tolerância a Glucose , Glibureto/farmacologia , Hipoglicemiantes/isolamento & purificação , Masculino , Metformina/farmacologia , Mioblastos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Ratos Wistar , EstreptozocinaRESUMO
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.
Assuntos
Rutaceae , Sesquiterpenos , Espectroscopia de Ressonância Magnética , Rutaceae/química , Sesquiterpenos/farmacologiaRESUMO
The air-dried powdered stem bark of Calophyllum nodusum (Guttiferea) collected from Sandakan (Sabah, Malaysia), was extracted sequentially with hexane, chloroform and methanol. The solvents were removed by rotary evaporator to give dark viscous extracts. Detailed and repeated chromatographic separation of the extracts lead to isolation of two new xanthones, identified as nodusuxanthone and trapezifolixanthone A. Other common terpenoids such as betulinic acid, lupeol, stigmasterol and friedelin were also isolated from the extracts and identified. The structures of the compounds were established by detailed spectral analysis and comparison with previously reported data.
Assuntos
Calophyllum/química , Casca de Planta/química , Extratos Vegetais/química , Xantonas/química , Xantonas/isolamento & purificação , Calophyllum/anatomia & histologia , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear BiomolecularRESUMO
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.
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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 ß-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 ß-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.
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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.
Assuntos
Antibacterianos/farmacologia , Enterococcus faecalis/crescimento & desenvolvimento , Sequestradores de Radicais Livres/farmacologia , Casca de Planta/química , Extratos Vegetais/química , Rutaceae/química , Streptococcus mutans/crescimento & desenvolvimento , Antibacterianos/química , Sequestradores de Radicais Livres/químicaRESUMO
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.
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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.
Assuntos
Abelhas/química , Mel/análise , Aprendizado de Máquina , Compostos Orgânicos Voláteis/análise , Animais , Análise por Conglomerados , Análise Discriminante , Análise dos Mínimos Quadrados , Filogenia , Análise de Componente PrincipalRESUMO
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, ß-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, ß-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.
Assuntos
Antioxidantes/química , Inibidores Enzimáticos/análise , Fenóis/análise , Extratos Vegetais/química , Sapindaceae/química , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Flavonoides/análise , Flavonoides/química , Frutas/química , Frutas/metabolismo , Fenóis/química , Sapindaceae/metabolismo , Espectrometria de Massas em Tandem , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismoRESUMO
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 ß-carotene bleaching. The DPPH activity of methanol extract and its fraction present the IC50 values of 54.3 and 168.9⯵g/mL meanwhile the ß-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⯵molâ¯TE/g respectively.