Displaying publications 141 - 160 of 160 in total

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  1. Malignant germ cell tumour in an infant vagina
    Saren MS, Ping EL, Ping WK
    Med J Malaysia, 2020 11;75(6):752-753.
    PMID: 33219193
    The mother of a 9-month-old female infant complained that her child was unable to pass urine at the same time noticing a mass protruding from the vaginal orifice.The infant had a single episode of vaginal bleeding.The primary concern of the mother was the inability of the daughter to micturate. Malignant germ cell tumour arising from an infant vagina is rare and accounts for about 3% of all paedriatic malignancies. These are also referred to as endodermal sinus tumours or yolk sac tumours, and are mostly the commonest form of infant vaginal malignancies encountered. A diagnosis of endodermal sinus tumour was established based on the histology and raised α-fetoprotein levels.These tumours had Schiller-Duval bodies which are primarily blood vessels surrounded by primordial germ cells and were periodic acid shift (PAS) positive diastase resistant hyaline globules which also stain positive with α- fetoprotein which is an important diagnostic feature. Tumours with high α-fetoprotein levels have a poorer prognosis. However, they respond satisfactorily to chemotherapy.
    Matched MeSH terms: Amylases
  2. Fulltext Nutritional compositions, biological activities, and phytochemical contents of the edible bamboo shoot, Dendrocalamus asper, from Malaysia
    Kong, C. K., Tan, Y. N., Chye, F. Y., Sit, N. W.
    International Food Research Journal, 2020;27(3):546-556.
    MyJurnal
    The edible shoots of Dendrocalamus asper (family Poaceae) is an underutilised food. The
    present work was conducted to evaluate the nutritional compositions, biological activities, and
    phytochemical contents of the shoots of D. asper obtained from different regions of Malaysia,
    Peninsular (DP) and East Malaysia (DS). The nutritional analysis was conducted using the
    Official Methods of Analysis of the AOAC International. All minerals were quantified using
    an inductively coupled plasma-mass spectrometer, except for potassium which was measured
    using a flame atomic absorption spectrometer. Total phenolic content (TPC) was determined
    using the Folin-Ciocalteu method. Antibacterial and antifungal activities were assayed using
    a colourimetric broth microdilution method, while antioxidant activity was tested using DPPH
    radical scavenging activity, ferric-reducing antioxidant power, and cellular antioxidant activity (CAA) assays. Enzyme inhibitory activities were examined using α-amylase and α-glucosidase. Both bamboo shoots (boiled at 100°C for 20 min) were high in moisture (> 93 g/100 g
    FW), crude protein (> 21 g/100 g DW), and crude fibre contents (> 9 g/100 g DW), but low in
    fat content (< 4 g/100 g DW). Potassium was the most abundant mineral at 205.67 and 203.83
    µg/100 g DW of bamboo shoots of DP and DS, respectively. The extracts (hexane, ethyl
    acetate, ethanol, and water) of both shoots showed stronger antifungal activity than antibacterial activity against selected human pathogens. All extracts of DP shoots demonstrated higher
    CAA in HeLa cells and α-amylase inhibitory activity than that of DS shoots. In contrast, the
    extracts of DS shoots exhibited stronger inhibition on α-glucosidase and contained higher
    TPC than that of DP shoots. The D. asper shoots obtained from the Peninsular Malaysia and
    East Malaysia contained different types of secondary metabolites which account for the differences in the biological activities. In conclusion, D. asper shoots have potential as a nutritional
    and functional food.
    Matched MeSH terms: alpha-Amylases
  3. Plant growth promoting and antifungal asset of indigenous rhizobacteria secluded from saffron (Crocus sativus L.) rhizosphere
    Rasool A, Imran Mir M, Zulfajri M, Hanafiah MM, Azeem Unnisa S, Mahboob M
    Microb Pathog, 2021 Jan;150:104734.
    PMID: 33429050 DOI: 10.1016/j.micpath.2021.104734
    Saffron (Crocus sativus L.) is an important plant in medicine. The Kashmir Valley (J&K, India) is one of the world's largest and finest saffron producing regions. However, over the past decade, there has been a strong declining trend in saffron production in this area. Plant Growth Promoting Rhizobacteria (PGPR) are free living soil bacteria that have ability to colonize the surfaces of the roots and ability to boost plant growth and development either directly or indirectly. Using the efficient PGPR as a bio-inoculant is another sustainable agricultural practice to improve soil health, grain yield quality, and biodiversity conservation. In the present study, a total of 13 bacterial strains were isolated from rhizospheric soil of saffron during the flowering stage of the tubers and were evaluated for various plant growth promoting characteristics under in vitro conditions such as the solubilization of phosphate, production of indole acetic acid, siderophore, hydrocyanic acid, and ammonia production and antagonism by dual culture test against Sclerotium rolfsii and Fusarium oxysporum. All the isolates were further tested for the production of hydrolytic enzymes such as protease, lipase, amylase, cellulase, and chitinase. The maximum proportions of bacterial isolates were gram-negative bacilli. About 77% of the bacterial isolates showed IAA production, 46% exhibited phosphate solubilization, 46% siderophore, 61% HCN, 100% ammonia production, 69% isolates showed protease activity, 62% lipase, 46% amylase, 85% cellulase, and 39% showed chitinase activity. Three isolates viz., AIS-3, AIS-8 and AIS-10 were found to have the most plant growth properties and effectively control the growth of Sclerotium rolfsii and Fusarium oxysporum. The bacterial isolates were identified as Brevibacterium frigoritolerans (AIS-3), Alcaligenes faecalis subsp. Phenolicus (AIS-8) and Bacillus aryabhattai (AIS-10) respectively by 16S rRNA sequence analysis. Therefore, these isolated rhizobacterial strains could be a promising source of plant growth stimulants to increase cormlets growth and increase saffron production.
    Matched MeSH terms: Amylases
  4. Transcriptomic and Proteomic Analyses of Nepenthes ampullaria and Nepenthes rafflesiana Reveal Parental Molecular Expression in the Pitchers of Their Hybrid, Nepenthes × hookeriana
    Zulkapli MM, Ab Ghani NS, Ting TY, Aizat WM, Goh HH
    Front Plant Sci, 2020;11:625507.
    PMID: 33552113 DOI: 10.3389/fpls.2020.625507
    Nepenthes is a genus comprising carnivorous tropical pitcher plants that have evolved trapping organs at the tip of their leaves for nutrient acquisition from insect trapping. Recent studies have applied proteomics approaches to identify proteins in the pitcher fluids for better understanding the carnivory mechanism, but protein identification is hindered by limited species-specific transcriptomes for Nepenthes. In this study, the proteomics informed by transcriptomics (PIT) approach was utilized to identify and compare proteins in the pitcher fluids of Nepenthes ampullaria, Nepenthes rafflesiana, and their hybrid Nepenthes × hookeriana through PacBio isoform sequencing (Iso-Seq) and liquid chromatography-mass spectrometry (LC-MS) proteomic profiling. We generated full-length transcriptomes from all three species of 80,791 consensus isoforms with an average length of 1,692 bp as a reference for protein identification. The comparative analysis found that transcripts and proteins identified in the hybrid N. × hookeriana were more resembling N. rafflesiana, both of which are insectivorous compared with omnivorous N. ampullaria that can derive nutrients from leaf litters. Previously reported hydrolytic proteins were detected, including proteases, glucanases, chitinases, phosphatases, nucleases, peroxidases, lipid transfer protein, thaumatin-like protein, pathogenesis-related protein, and disease resistance proteins. Many new proteins with diverse predicted functions were also identified, such as amylase, invertase, catalase, kinases, ligases, synthases, esterases, transferases, transporters, and transcription factors. Despite the discovery of a few unique enzymes in N. ampullaria, we found no strong evidence of adaptive evolution to produce endogenous enzymes for the breakdown of leaf litter. A more complete picture of digestive fluid protein composition in this study provides important insights on the molecular physiology of pitchers and carnivory mechanism of Nepenthes species with distinct dietary habits.
    Matched MeSH terms: Amylases
  5. Fulltext Native to designed: microbial -amylases for industrial applications
    Lim SJ, Oslan SN
    PeerJ, 2021;9:e11315.
    PMID: 34046253 DOI: 10.7717/peerj.11315
    Background: -amylases catalyze the endo-hydrolysis of -1,4-D-glycosidic bonds in starch into smaller moieties. While industrial processes are usually performed at harsh conditions, -amylases from mainly the bacteria, fungi and yeasts are preferred for their stabilities (thermal, pH and oxidative) and specificities (substrate and product). Microbial -amylases can be purified and characterized for industrial applications. While exploring novel enzymes with these properties in the nature is time-costly, the advancements in protein engineering techniques including rational design, directed evolution and others have privileged their modifications to exhibit industrially ideal traits. However, the commentary on the strategies and preferably mutated residues are lacking, hindering the design of new mutants especially for enhanced substrate specificity and oxidative stability. Thus, our review ensures wider accessibility of the previously reported experimental findings to facilitate the future engineering work.

    Survey methodology and objectives: A traditional review approach was taken to focus on the engineering of microbial -amylases to enhance industrially favoured characteristics. The action mechanisms of - and -amylases were compared to avoid any bias in the research background. This review aimed to discuss the advances in modifying microbial -amylases via protein engineering to achieve longer half-life in high temperature, improved resistance (acidic, alkaline and oxidative) and enhanced specificities (substrate and product). Captivating results were discussed in depth, including the extended half-life at 100C, pH 3.5 and 10, 1.8 M hydrogen peroxide as well as enhanced substrate (65.3%) and product (42.4%) specificities. These shed light to the future microbial -amylase engineering in achieving paramount biochemical traits ameliorations to apt in the industries.

    Conclusions: Microbial -amylases can be tailored for specific industrial applications through protein engineering (rational design and directed evolution). While the critical mutation points are dependent on respective enzymes, formation of disulfide bridge between cysteine residues after mutations is crucial for elevated thermostability. Amino acids conversion to basic residues was reported for enhanced acidic resistance while hydrophobic interaction resulted from mutated hydrophobic residues in carbohydrate-binding module or surface-binding sites is pivotal for improved substrate specificity. Substitution of oxidation-prone methionine residues with non-polar residues increases the enzyme oxidative stability. Hence, this review provides conceptual advances for the future microbial -amylases designs to exhibit industrially significant characteristics. However, more attention is needed to enhance substrate specificity and oxidative stability since they are least reported.

    Matched MeSH terms: Amylases
  6. Fulltext Antidiabetic and In Vitro Enzyme Inhibition Studies of Methanol Extract of Ocimum tenuiflorum Linn Leaves and Its Fractions
    Mousavi L, Salleh RM, Murugaiyah V
    Trop Life Sci Res, 2020 Apr;31(1):141-158.
    PMID: 32963716 DOI: 10.21315/tlsr2020.31.1.9
    The current study aimed to determine the best dose of methanol extract of Ocimum tenuiflorum L. leaves extract, and it is a fraction to blood-glucose-lowering in diabetic rats, and evaluated the α-amylase, α-glucosidase inhibitors and insulin level of diabetic rats used to achieve greater control over hyperglycemia. The result of the antihyperglycaemic of oral administration of a different dose of methanol extract in streptozotocin-induced rats showed that the highest dose of methanol extract significantly reduced the blood glucose level compared to another dose. Also, the result of repeated administration of methanol fractions indicates that ethyl acetate-butanol fraction exhibited a stronger antihyperglycemic effect than chloroform and ethanol-water fractions. Moreover, the result showed that effect of methanol extract and its fraction on α-glucosidase and α-amylase enzymes activities and its insulin level by in vitro study, ethyl acetate-butanol fraction could control with low concentration compared to other fractions and acarbose that used as a positive control. From the result of insulin level, methanol extract and fraction did not show any significant. These findings indicated that the active crude extract (methanol) and its active fractions (ethyl acetate/butanol) could exert significant glucose-lowering effect due to the presence of polyphenolics active constituents. In conclusion, isolation of the active components of Ocimum tenuiflorum L. may pave the way to the development of new agents for the treatment of diabetes and its complications.
    Matched MeSH terms: alpha-Amylases
  7. Biochemical studies of Piper betle L Leaf Extract on Obese Treated Animal using 1H-NMR-Based Metabolomic Approach of Blood Serum Samples
    Abdul Ghani ZD, Husin JM, Rashid AH, Shaari K, Chik Z
    J Ethnopharmacol, 2016 Oct 7.
    PMID: 27725236 DOI: 10.1016/j.jep.2016.10.022
    Piper Betle L. (PB) belongs to the Piperaceae family. The presence of a fairly large quantity of diastase in the betel leaf is deemed to play an important role in starch digestion and calls for the study of weight loss activities and metabolite profile from PB leaf extracts using metabolomics approach to be performed. PB dried leaves were extracted with 70% ethanol and the extracts were subjected to five groups of rats fed with high fat (HF) and standard diet (SD). They were then fed with the extracts in two doses and compared with a negative control group given water only according to the study protocol. The body weights and food intakes were monitored every week. At the end of the study, blood serum of the experimental animal was analysed to determine the biochemical and metabolite changes. PB treated group demonstrated inhibition of body weight gain without showing an effect on the food intake. In serum bioassay, the PB treated group (HF/PB (100mg/kg and 500mg/kg) showed an increased in glucose and cholesterol levels compared to the Standard Diet (SD/WTR) group, a decrease in LDL level and increase in HDL level when compared with High Fat Diet (HF/WTR) group. For metabolite analysis, two separation models were made to determine the metabolite changes via group activities. The best separation of PCA serum in Model 1 and 2 was achieved in principle component 1 and principle component 2. SUS-Plot model showed that HF group was characterized by high-level of glucose, glycine and alanine. Increase in the β-hydroxybutyrate level similar with SD group animals was evident in the HF/PB(500mg/kg) group. This finding suggested that the administration of 500mg/kg PB extracts leads to increase in oxidation process in the body thus maintaining the body weight and without giving an effect on the appetite even though HF was continuously consumed by the animals until the end of the studies and also a reduction in food intake, thus maintaining their body weight although they were continuously consumed HF.
    Matched MeSH terms: Amylases
  8. Biliary ascariasis: a wandering worm
    Lim, C.B., Munirah, A., Alias, M., Nandy, A.K., Thamby Dorai, C.R.
    Malaysian Journal of Paediatrics and Child Health, 2000;12(1):68-71.
    MyJurnal
    Ascaris lumbricoides infection usually results in mild gastrointestinal symptoms. However, heavy worm load infections can cause major complications. In one-third of the latter cases, the worms enter the bile duct causing cholangitis, biliary colic and acute pancreatitis. We describe an eleven-year-old Indian boy who presented with high grade fever, vomiting of worms, jaundice and right hypochondria! pain. Examination revealed an ill, malnourished and jaundiced child. His abdomen was tender with positive Murphy's sign and hepatomegaly. Urgent ultrasound showed hepatomegaly with dilated intrahepatic and common bile ducts (CBD). There were tubular echogenic filling defects with central sonolucency along the long axis of the CBD. He was fasted, started on intravenous fluids and broad spectrum antibiotics. As there was no improvement after 24 hours, endoscopic retrograde cholangio-pancreaticography (ERCP) was performed: it showed worms in the CBD. A stent was inserted to decompress the bile ducts and to ensure biliary drainage. The patient improved, the fever settled, jaundice resolved, serum amylase and transaminase levels normalised. It was planned to remove the stent at a later date.
    Matched MeSH terms: Amylases
  9. Fulltext Evaluation of the glycemic effect of Ceratonia siliqua pods (Carob) on a streptozotocin-nicotinamide induced diabetic rat model
    Qasem MA, Noordin MI, Arya A, Alsalahi A, Jayash SN
    PeerJ, 2018;6:e4788.
    PMID: 29844959 DOI: 10.7717/peerj.4788
    Background: Ceratonia siliqua pods (carob) have been nominated to control the high blood glucose of diabetics. In Yemen, however, its antihyperglycemic activity has not been yet assessed. Thus, this study evaluated the in vitro inhibitory effect of the methanolic extract of carob pods against α-amylase and α-glucosidase and the in vivo glycemic effect of such extract in streptozotocin-nicotinamide induced diabetic rats.

    Methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric reducing antioxidant power assay (FRAP) were applied to evaluate the antioxidant activity of carob. In vitro cytotoxicity of carob was conducted on human hepatocytes (WRL68) and rat pancreatic β-cells (RIN-5F). Acute oral toxicity of carob was conducted on a total of 18 male and 18 female Sprague-Dawley (SD) rats, which were subdivided into three groups (n = 6), namely: high and low dose carob-treated (CS5000 and CS2000, respectively) as well as the normal control (NC) receiving a single oral dose of 5,000 mg kg-1 carob, 2,000 mg kg-1 carob and 5 mL kg-1 distilled water for 14 days, respectively. Alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, total bilirubin, creatinine and urea were assessed. Livers and kidneys were harvested for histopathology. In vitro inhibitory effect against α-amylase and α-glucosidase was evaluated. In vivo glycemic activity was conducted on 24 male SD rats which were previously intraperitoneally injected with 55 mg kg-1 streptozotocin (STZ) followed by 210 mg kg-1nicotinamide to induce type 2 diabetes mellitus. An extra non-injected group (n = 6) was added as a normal control (NC). The injected-rats were divided into four groups (n = 6), namely: diabetic control (D0), 5 mg kg-1glibenclamide-treated diabetic (GD), 500 mg kg-1 carob-treated diabetic (CS500) and 1,000 mg kg-1 carob-treated diabetic (CS1000). All groups received a single oral daily dose of their treatment for 4 weeks. Body weight, fasting blood glucose (FBG), oral glucose tolerance test, biochemistry, insulin and hemostatic model assessment were assessed. Pancreases was harvested for histopathology.

    Results: Carob demonstrated a FRAP value of 3191.67 ± 54.34 µmoL Fe++ and IC50 of DPPH of 11.23 ± 0.47 µg mL-1. In vitro, carob was non-toxic on hepatocytes and pancreatic β-cells. In acute oral toxicity, liver and kidney functions and their histological sections showed no abnormalities. Carob exerted an in vitro inhibitory effect against α-amylase and α-glucosidase with IC50 of 92.99 ± 0.22 and 97.13 ± 4.11 µg mL-1, respectively. In diabetic induced rats, FBG of CS1000 was significantly less than diabetic control. Histological pancreatic sections of CS1000 showed less destruction of β-cells than CS500 and diabetic control.

    Conclusion: Carob pod did not cause acute systemic toxicity and showed in vitro antioxidant effects. On the other hand, inhibiting α-amylase and α-glucosidase was evident. Interestingly, a high dose of carob exhibits an in vivo antihyperglycemic activity and warrants further in-depth study to identify the potential carob extract composition.

    Matched MeSH terms: alpha-Amylases
  10. Antidiabetic activities of chloroform fraction of Anthocleista vogelii Planch root bark in rats with diet- and alloxan-induced obesity-diabetes
    Anyanwu GO, Iqbal J, Khan SU, Zaib S, Rauf K, Onyeneke CE, et al.
    J Ethnopharmacol, 2018 Oct 18.
    PMID: 30342966 DOI: 10.1016/j.jep.2018.10.021
    ETHNOPHARMACOLOGICAL RELEVANCE: Anthocleista vogelii Planch is a medicinal plant traditionally used in West Africa for the management and treatment of diabetes mellitus.

    AIM OF THE STUDY: To determine the antidiabetic activities of chloroform fraction (CF) of Anthocleista vogelii Planch root bark in rats with diet- and alloxan-induced obesity-diabetes.

    MATERIALS AND METHODS: Inhibitory activities of CF against α-amylase and α-glucosidase activities were determined in vitro. Three weeks old rats were fed with high-fat diet for 9 weeks to induce obesity prior to further induction of diabetes using alloxan (150mg/kg body weight, i.p.). Blood glucose levels and body weight were measured every 7 days throughout the experiment. Glucose tolerance was assessed in normal and CF-treated rats on day 21. Terminal blood samples were collected from sacrificed animals for the measurement of serum insulin levels. Pancreases were excised from treated and untreated animals for histopathological examination.

    RESULTS: LCMS/MS chromatographic profile of CF via positive and negative modes revealed 13 and 23 compounds respectively. Further analysis revealed quebrachitol (QCT), loganin, sweroside, oleoside 11-methyl ester and ferulic acid, which have been previously reported for their antidiabetic activities, as constituents of CF. CF inhibited activities of α-amylase (IC50 = 51.60 ± 0.92µg/ml) and α-glucosidase (IC50 = 5.86 ± 0.97µg/ml) in a dose-dependent manner. Treatment of animals with obesity-diabetes with 100 and 200mg/kg CF significantly improved glucose tolerance (P<0.001) and enhanced serum insulin levels (P<0.05) compared to diabetic control rats.

    CONCLUSIONS: Antidiabetic activities of CF might be mediated via inhibition of α-amylase and α-glucosidase activities, elevation of serum insulin concentration, and enhancement of insulin and leptin sensitivity in obesity-diabetes rats. This study further substantiates the traditional use of A. vogelii in the management and treatment of diabetes in Africa and encourages further studies to investigate its mechanism of action.

    Matched MeSH terms: alpha-Amylases
  11. Fulltext Determination of folate content in commonly consumed Malaysian foods
    Chew, S.C., Loh, S.P., Khor, G.L.
    International Food Research Journal, 2012;19(1):189-197.
    MyJurnal
    Currently, data concerning the content of naturally occurring dietary folate in Malaysian foods is scarce. The aim of this study was to determine the folate content of vegetables, fruits, legumes and cereals that were commonly consumed among Malaysians. The total folate content of 156 samples (51 vegetables, 33 fruits, 22 legumes and legume products, and 50 cereals and cereal products) available in Malaysia was determined by microbiological assay using Lactobacillus casei (L. casei) after trienzyme treatment with protease, α-amylase and folate conjugase (from rat serum). An internal quality control system was used throughout the study by analyzing CRM 121 (wholemeal flour) and CRM 485 (lyophilized mixed vegetables); percent recovery (as mean ± SD) of 97 ± 2.0 and 101 ± 4.0 was obtained. The range of folate content in vegetables, fruits, legumes and cereals were 1-11 μg/100 g and 1-31on the basis of fresh weight and 1-31 µg/100 g and 2-156 µg/100 g on the basis of dry weight, respectively. This study has shown that some of these underutilized vegetables and fruits are good sources of folate and could fulfill the recommended dietary intake of total folate.
    Matched MeSH terms: alpha-Amylases
  12. New pyrrolopyridine-based thiazolotriazoles as diabetics inhibitors: enzymatic kinetics and in silico study
    Taha M, Rahim F, Hayat S, Chigurupati S, Khan KM, Imran S, et al.
    Future Med Chem, 2023 Mar;15(5):405-419.
    PMID: 37013918 DOI: 10.4155/fmc-2022-0306
    Aim: To synthesize pyrrolopyridine-based thiazolotriazoles as a novel class of α-amylase and α-glucosidase inhibitors and to determine their enzymatic kinetics. Methodology: Pyrrolopyridine-based thiazolotriazole analogs (1-24) were synthesized and characterized through proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance and high-resolution electron ionization mass spectrometry. Results: All synthesized analogs displayed good inhibitory potential of α-amylase and α-glucosidase ranging 17.65-70.7 μM and 18.15-71.97 μM, respectively, compared with the reference drug, acarbose (11.98 μM and 12.79 μM). Analog 3 was the most potent among the synthesized analogs, having α-amylase and α-glucosidase inhibitory activity at 17.65 and 18.15 μM, respectively. The structure-activity relationship and binding modes of interactions between selected analogs were confirmed via docking and enzymatic kinetics studies. The compounds (1-24) were tested for cytotoxicity against the 3T3 mouse fibroblast cell line and were observed to be nontoxic.
    Matched MeSH terms: alpha-Amylases
  13. Molecular dynamics simulations reveal the inhibitory mechanism of Withanolide A against α-glucosidase and α-amylase
    Oyewusi HA, Wu YS, Safi SZ, Wahab RA, Hatta MHM, Batumalaie K
    J Biomol Struct Dyn, 2023;41(13):6203-6218.
    PMID: 35904027 DOI: 10.1080/07391102.2022.2104375
    Diabetes mellitus (DM) is a global chronic disease characterized by hyperglycemia and insulin resistance. The unsavory severe gastrointestinal side-effects of synthetic drugs to regulate hyperglycemia have warranted the search for alternative treatments to inhibit the carbohydrate digestive enzymes (e.g. α-amylase and α-glucosidase). Certain phytochemicals recently captured the scientific community's attention as carbohydrate digestive enzyme inhibitors due to their low toxicity and high efficacy, specifically the Withanolides-loaded extract of Withania somnifera. That said, the present study evaluated in silico the efficacy of Withanolide A in targeting both α-amylase and α-glucosidase in comparison to the synthetic drug Acarbose. Protein-ligand interactions, binding affinity, and stability were characterized using pharmacological profiling, high-end molecular docking, and molecular-dynamic simulation. Withanolide A inhibited the activity of α-glucosidase and α-amylase better, exhibiting good pharmacokinetic properties, absorption, and metabolism. Also, Withanolide A was minimally toxic, with higher bioavailability. Interestingly, Withanolide A bonded well to the active site of α-amylase and α-glucosidase, yielding the lowest binding free energy of -82.144 ± 10.671 kcal/mol and -102.1043 ± 11.231 kcal/mol compared to the Acarbose-enzyme complexes (-63.220 ± 13.283 kcal/mol and -82.148 ± 10.671 kcal/mol). Hence, the findings supported the therapeutic potential of Withanolide A as α-amylase and α-glucosidase inhibitor for DM treatment.Communicated by Ramaswamy H. Sarma.
    Matched MeSH terms: alpha-Amylases
  14. Fulltext Comparative Investigation of Chemical Constituents of Kernels, Leaves, Husk, and Bark of Juglans regia L., Using HPLC-DAD-ESI-MS/MS Analysis and Evaluation of Their Antioxidant, Antidiabetic, and Anti-Inflammatory Activities
    Bourais I, Elmarrkechy S, Taha D, Badaoui B, Mourabit Y, Salhi N, et al.
    Molecules, 2022 Dec 16;27(24).
    PMID: 36558122 DOI: 10.3390/molecules27248989
    Leaves, husk, kernels, and bark methanolic extracts of Juglans regia L. were tested for their in vitro antidiabetic, anti-inflammatory, and antioxidant activities. For these purposes, α-amylase and α-glucosidase were used as the main enzymes to evaluate antidiabetic activities. Moreover, lipoxidase and tyrosinase activities were tested to estimate anti-inflammatory properties. Antioxidant properties of Juglans regia L., extracts were determined using three different assays. Leaves extract has an important radical scavenging activity and a-amylase inhibition. Similarly, husk extracts showed high total phenolic content (306.36 ± 4.74 mg gallic acid equivalent/g dry extract) with an important α-amylase inhibition (IC50 = 75.42 ± 0.99 µg/mL). Kernels exhibit significant tyrosinase (IC50 = 51.38 ± 0.81 µg/mL) correlated with antioxidant activities (p < 0.05). Husk and bark extracts also showed strong anti-lipoxidase activities with IC50 equal to 29.48 ± 0.28 and 28.58 ± 0.35 µg/mL, respectively. HPLC-DAD-ESI-MS/MS analysis highlights the phenolic profile of methanolic extracts of Juglans regia L. plant parts. The identified polyphenols were known for their antioxidant, antidiabetic (dicaffeoyl-quinic acid glycoside in kernels), and anti-inflammatory (3,4-dihydroxybenzoic acid in leaves) activities. Further investigations are needed to determine molecular mechanisms involved in these effects as well as to study the properties of the main identified compounds.
    Matched MeSH terms: alpha-Amylases
  15. Fulltext In vitro and in vivo effects of standardized extract and fractions of Phaleria macrocarpa fruits pericarp on lead carbohydrate digesting enzymes
    Ali RB, Atangwho IJ, Kuar N, Ahmad M, Mahmud R, Asmawi MZ
    BMC Complement Altern Med, 2013;13:39.
    PMID: 23425283 DOI: 10.1186/1472-6882-13-39
    One vital therapeutic approach for the treatment of type 2 diabetes mellitus is the use of agents that can decrease postprandial hyperglycaemia by inhibiting carbohydrate digesting enzymes. The present study investigated the effects of bioassay-guided extract and fractions of the dried fruit pericarp of Phaleria macrocarpa, a traditional anti-diabetic plant, on α-glucosidase and α-amylase, in a bid to understand their anti-diabetic mechanism, as well as their possible attenuation action on postprandial glucose increase.
    Matched MeSH terms: alpha-Amylases/antagonists & inhibitors*
  16. Fulltext In vitro inhibitory potential of selected Malaysian plants against key enzymes involved in hyperglycemia and hypertension
    Loh SP, Hadira O
    Malays J Nutr, 2011 Apr;17(1):77-86.
    PMID: 22135867 MyJurnal
    This study was conducted to determine the inhibitory potential of selected Malaysian plants against key enzymes related to type 2 diabetes and hypertension.
    Matched MeSH terms: alpha-Amylases/antagonists & inhibitors
  17. HPTLC based approach for bioassay-guided evaluation of antidiabetic and neuroprotective effects of eight essential oils of the Lamiaceae family plants
    Romero Rocamora C, Ramasamy K, Meng Lim S, Majeed ABA, Agatonovic-Kustrin S
    J Pharm Biomed Anal, 2020 Jan 30;178:112909.
    PMID: 31618702 DOI: 10.1016/j.jpba.2019.112909
    A high-performance thin-layer chromatography (HPTLC) method combined with effect-directed-analysis (EDA) was developed to screen the antioxidant, neuroprotective and antidiabetic effects in essential oils derived from lavender flower, lemon myrtle, oregano, peppermint, sage, and rosemary leaves (Lamiaceae family). HPTLC hyphenated with microchemical (DPPH•, p-anisaldehyde, and ferric chloride) derivatizations, was used to evaluate antioxidant activity, presence of phytosterols and terpenoids, and polyphenolic content, while the combination with biochemical (α-amylase and acetylcholine esterase (AChE) enzymatic) derivatizations was used to asses α-amylase and AChE inhibitory activities. The superior antioxidant activity of oregano leaf extract is attributed to the presence of high levels of aromatic compounds, like polyphenolic acids. The strongest α-amylase inhibition was observed in lemon myrtle and rosemary plus extracts due to the presence of monoterpenes. Rosemary and sage extracts exhibit the highest AChE inhibition activity, with 1 μL essential oils being more potent than the recommended daily dose of donepezil. This superior neuroprotection was attributed to the presences of di- and triterpenes that displayed strong AChE inhibition and antioxidant potential in DPPH• free radical assay. Antioxidant activity was related to phenolic content (R = 0.49), while α-amylase inhibitory activity was positively related to antioxidant activity (R = 0.20) and terpenoid/sterol content (R = 0.31). AChE inhibitory activity was correlated (R = 0.80) to the combined effect of phenolics and terpenoids. Thus, the superior AChE inhibitory and neuroprotection potential of rosemary and sage essential oils could be attributed to joint effects of main phenolic and terpene constituents. The hyphenated HPTLC method provided rapid bioanalytical profiling of highly complex essential oil samples.
    Matched MeSH terms: alpha-Amylases/metabolism
  18. Fulltext In vitro alpha-glucosidase and alpha-amylase enzyme inhibitory effects of Andrographis paniculata extract and andrographolide
    Subramanian R, Asmawi MZ, Sadikun A
    Acta Biochim. Pol., 2008;55(2):391-8.
    PMID: 18511986
    There has been an enormous interest in the development of alternative medicines for type 2 diabetes, specifically screening for phytochemicals with the ability to delay or prevent glucose absorption. The goal of the present study was to provide in vitro evidence for potential inhibition of alpha-glucosidase and alpha-amylase enzymes, followed by a confirmatory in vivo study on rats to generate a stronger biochemical rationale for further studies on the ethanolic extract of Andrographis paniculata and andrographolide. The extract showed appreciable alpha-glucosidase inhibitory effect in a concentration-dependent manner (IC(50)=17.2+/-0.15 mg/ml) and a weak alpha-amylase inhibitory activity (IC(50)=50.9+/-0.17 mg/ml). Andrographolide demonstrated a similar (IC(50)=11.0+/-0.28 mg/ml) alpha-glucosidase and alpha-amylase inhibitory activity (IC(50)=11.3+/-0.29 mg/ml). The positive in vitro enzyme inhibition tests paved way for confirmatory in vivo studies. The in vivo studies demonstrated that A. paniculata extract significantly (P<0.05) reduced peak blood glucose and area under curve in diabetic rats when challenged with oral administration of starch and sucrose. Further, andrographolide also caused a significant (P<0.05) reduction in peak blood glucose and area under the curve in diabetic rats. Hence alpha-glucosidase inhibition may possibly be one of the mechanisms for the A. paniculata extract to exert antidiabetic activity and indicates that AP extract can be considered as a potential candidate for the management of type 2 diabetes mellitus.
    Matched MeSH terms: alpha-Amylases/antagonists & inhibitors*
  19. The role of digestive factors in determining glycemic response in a multiethnic Asian population
    Tan VM, Ooi DS, Kapur J, Wu T, Chan YH, Henry CJ, et al.
    Eur J Nutr, 2016 Jun;55(4):1573-81.
    PMID: 26160548 DOI: 10.1007/s00394-015-0976-0
    PURPOSE: There are wide inter-individual differences in glycemic response (GR). We aimed to examine key digestive parameters that influence inter-individual and ethnic differences in GR in healthy Asian individuals.
    METHODS: Seventy-five healthy male subjects (25 Chinese, 25 Malays, and 25 Asian-Indians) were served equivalent available carbohydrate amounts (50 g) of jasmine rice (JR) and basmati rice (BR) on separate occasions. Postprandial blood glucose concentrations were measured at fasting (-5 and 0 min) and at 15- to 30-min interval over 180 min. Mastication parameters (number of chews per mouth and chewing time per mouthful), saliva α-amylase activity, AMY1 gene copy numbers and gastric emptying rate were measured to investigate their relationships with GR.
    RESULTS: The GR for jasmine rice was significantly higher than for basmati rice (P 0.05).
    CONCLUSION: Mastication parameters contribute significantly to GR. Eating slowly and having larger food boluses before swallowing (less chewing), both potentially modifiable, may be beneficial in glycemic control.
    Matched MeSH terms: Salivary alpha-Amylases/genetics
  20. Combination of phenolic profiles, pharmacological properties and in silico studies to provide new insights on Silene salsuginea from Turkey
    Zengin G, Rodrigues MJ, Abdallah HH, Custodio L, Stefanucci A, Aumeeruddy MZ, et al.
    Comput Biol Chem, 2018 Dec;77:178-186.
    PMID: 30336375 DOI: 10.1016/j.compbiolchem.2018.10.005
    The genus Silene is renowned in Turkey for its traditional use as food and medicine. Currently, there are 138 species of Silene in Turkey, amongst which have been several studies for possible pharmacological potential and application in food industry. However, there is currently a paucity of data on Silene salsuginea Hub.-Mor. This study endeavours to access its antioxidant, enzyme inhibitory, and anti-inflammatory properties. Besides, reversed-phase high-performance liquid chromatography-diode array detector (RP-HPLC-DAD) was used to detect phenolic compounds, and molecular docking was performed to provide new insights for tested enzymes and phenolics. High amounts of apigenin (534 μg/g extract), ferulic acid (452 μg/g extract), p-coumaric acid (408 μg/g extract), and quercetin (336 μg/g extract) were detected in the methanol extract while rutin (506 μg/g extract) was most abundant in the aqueous extract. As for their biological properties, the methanol extract exhibited the best antioxidant effect in the DPPH and CUPRAC assays, and also the highest inhibition against tyrosinase. The aqueous extract was the least active enzyme inhibitor but showed the highest antioxidant efficacy in the ABTS, FRAP, and metal chelating assays. At a concentration of 15.6 μg/mL, the methanol extract resulted in a moderate decrease (25.1%) of NO production in lipopolysaccharide-stimulated cells. Among the phenolic compounds, epicatechin, (+)-catechin, and kaempferol showed the highest binding affinity towards the studied enzymes in silico. It can be concluded that extracts of S. salsuginea are a potential source of functional food ingredients but need further analytical experiments to explore its complexity of chemical compounds and pharmacological properties as well as using in vivo toxicity models to establish its maximum tolerated dose.
    Matched MeSH terms: alpha-Amylases/antagonists & inhibitors; alpha-Amylases/metabolism
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