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result(s) for
"Sterculia - chemistry"
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Antibacterial and Healing Effect of Chicha Gum Hydrogel (Sterculia striata) with Nerolidol
by
Lima, Idglan Sá de
,
Estevinho, Leticia M.
,
Ribeiro, Alessandra Braga
in
Anti-Bacterial Agents - chemistry
,
Antimicrobial agents
,
Decomposition
2023
Chicha gum is a natural polymer obtained from the Sterculia striata plant. The hydroxyl groups of its structure have a chemical affinity to form hydrogels, which favors the association with biologically active molecules, such as nerolidol. This association improves the biological properties and allows the material to be used in drug delivery systems. Chicha gum hydrogels associated with nerolidol were produced at two concentrations: 0.01 and 0.02 g mL−1. Then, the hydrogels were characterized by thermogravimetry (TG), Fourier Transform Infrared spectroscopy (FTIR), and rheological analysis. The antibacterial activity was tested against Staphylococcus aureus and Escherichia coli. The cytotoxicity was evaluated against Artemia salina. Finally, an in vivo healing assay was carried out. The infrared characterization indicated that interactions were formed during the gel reticulation. This implies the presence of nerolidol in the regions at 3100–3550 cm−1. The rheological properties changed with an increasing concentration of nerolidol, which resulted in less viscous materials. An antibacterial 83.6% growth inhibition effect was observed using the hydrogel with 0.02 g mL−1 nerolidol. The in vivo healing assay showed the practical activity of the hydrogels in the wound treatment, as the materials promoted efficient re-epithelialization. Therefore, it was concluded that the chicha hydrogels have the potential to be used as wound-healing products.
Journal Article
Green Extraction of Natural Antioxidants from the Sterculia nobilis Fruit Waste and Analysis of Phenolic Profile
2018
The waste of Sterculia nobilis fruit was massively produced during food processing, which contains lots of natural antioxidants. In this study, antioxidants in the Sterculia nobilis fruit waste were extracted using the green microwave-assisted extraction (MAE) technique. The effects of five independent variables (ethanol concentration, solvent/material ratio, extraction time, temperature, and microwave power) on extraction efficiency were explored, and three major factors (ethanol concentration, extraction time, and temperature) showing great influences were chosen to study their interactions by response surface methodology. The optimal conditions were as follows: 40.96% ethanol concentration, 30 mL/g solvent/material ratio, 37.37 min extraction time at 66.76 °C, and 700 W microwave power. The Trolox equivalent antioxidant capacity value obtained in optimal conditions was in agreement with the predicted value. Besides, MAE improved the extraction efficiency compared with maceration and Soxhlet extraction methods. Additionally, the phenolic profile in the extract was analyzed by UPLC-MS/MS, and eight kinds of phenolic compounds were identified and quantified, including epicatechin, protocatechuic acid, ferulic acid, gallic acid, p-coumaric acid, caffeic acid, quercetin, and p-hydroxycinnamic acid. This study could contribute to the value-added utilization of the waste from Sterculia nobilis fruit, and the extract could be developed as food additive or functional food.
Journal Article
Optimisation, experimental validation and thermodynamic study of the sequential oil extraction and biodiesel production processes from seeds of Sterculia foetida
by
Sambasivam, Kavitha Muniswamy
,
Murugavelh, Somasundaram
in
Acids
,
Activation energy
,
Aquatic Pollution
2019
Non-edible seeds are not used in any commercial applications, which implies that they can be used for biofuel applications. The present study aimed to maximise the process conditions for oil extraction and sterculia biodiesel production from
Sterculia foetida
(
poon oil
). GC-MS identified the methyl esters of sterculia oil as sterculic acid (32%), palmitic acid (15.88%), oleic acid (10.00%), linoleic acid (9.95%) and malvalic acid (9%). Response surface methodology (RSM) based parametric optimisation of oil extraction was carried out by choosing process variables such as sample weight, volume of solvent to seed ratio and time. The optimum sample amount of 7.5 g and the volume of solvent to seed ratio of 40 mL/g resulted in a maximum oil yield of 45.27% at 3 h. The results were statistically significant (
P
< 0.05) with a regression coefficient (
R
2
) of 0.9988. Furthermore, the artificial neural network (ANN) resulted in an
R
2
value greater than 0.9, which validates the RSM. Conventional optimisation of the temperature (55 °C), feedstock to methanol ratio (1:12), catalyst proportion (1.5%) and transesterification reaction time (60 min) yield 90.87% biodiesel production. The physicochemical characteristics of oil and biodiesel complied with the requirements of the ASTM standards. The rate constant and thermodynamic variables at the optimum temperature (333 K) were calculated from the experimental data. The activation energy (
E
a
), activation enthalpy in transition state theory (
ΔH
++
), activation entropy in transition state theory (
ΔS
++
) and Gibbs free energy in transition state theory (
ΔG
++
) were 37.91 kJ mol
−1
, 35.14 kJ mol
−1
, − 239.58 J mol
−1
K
−1
and 79.81 kJ mol
−1
respectively.
Graphical abstract
Journal Article
Evaluation of the antileishmanial potency, toxicity and phytochemical constituents of methanol bark extract of Sterculia villosa
2017
Context: Visceral leishmaniasis is a protozoan disease caused by Leishmania donovani parasite. The genus Sterculia (Malvaceae) possesses ethnobotanical potential against this protozoan infection.Objective: Determining the potential role of methanol bark extracts from Sterculia villosa Roxb (SVE) and its phytoconstituents against Leishmania donovani promastigotes.Materials and methods: SVE was analysed by TLC, UV–Vis, IR spectroscopy and biochemical assays. Antileishmanial potential of SVE (0.5–130 μg/mL for 72 h) was characterized by MTT assay. Fluorescent microscopy was performed to validate the IC50 dose. To determine the effect of SVE on promastigotes, reactive oxygen species (ROS) and superoxide generation, lipid peroxidation and DNA fragmentation assays were performed. Molecular aggregation of compounds was determined by atomic force microscopy (AFM). Extent of cytotoxicity of SVE at IC50 dose was determined against RAW 264.7 macrophages, peritoneal macrophages and murine RBCs. In vivo cytotoxicity of SVE was evaluated in BALB/c mice.Result: SVE exhibited reverse dose dependent antileishmanial activity when 130–0 μg/mL doses were tested against promastigotes. The IC50 and IC70 values were found to be 17.5 and 10 μg/mL, respectively. SVE at IC50 dose demonstrated elevated level of ROS, superoxide, lipid peroxidation and DNA fragmentation against promastigotes with no cytotoxicity. AFM analysis suggested increasing size of molecular aggregation (31.3 nm < 35.2 nm < 2.93 μm) with increase in concentration (10 μg < 17.5 μg < 130 μg).Discussion and conclusions: The study elucidates the antileishmanial potential of SVE against Leishmania donovani promastigotes by exerting oxidative stress and DNA damage. In sum, SVE can be explored as an immunotherapeutic candidate against leishmaniasis and other infectious diseases.
Journal Article
Antibacterial and Hemolytic Activity of a new Lectin Purified from the Seeds of Sterculia Foetida L
by
Cardoso, Juscélio Donizete
,
Braga, Alana Araújo
,
e Lacerda, Rodrigo Rodrigues
in
Animals
,
Anti-Bacterial Agents - pharmacology
,
antibacterial properties
2015
The aim of this study was to isolate, characterize, and verify possible antibacterial and hemolytic activity for a lectin found in the seeds of Sterculia foetida L. Purification of the lectin from S. foetida (SFL) was realized with ion exchange chromatography DEAE-Sephacel coupled to HPLC. The purity and the molecular weight was determined by SDS-PAGE. The isolated SFL was characterized as to its glycoprotein nature, and sugar specificity, as well as resistance to pH, temperature, denaturing agents, reduction, oxidation, and chelation. A microdilution method was used to determine antibacterial activity, and hemolytic activity was observed in human erythrocytes. The SFL has a molecular weight of 17 kDa, and a carbohydrate content of 53 μg/mL, specific for arabinose and xylose, and is resistant to treatment with urea, sensitive to treatment with sodium metaperiodate and β-mercaptoethanol, and in the presence of EDTA lost its hemagglutinating activity (HA). However, in the presence of divalent cations (Ca² ⁺and Mn² ⁺) the HA was increased. The SFL remained active even after incubation at 80 °C, and, within pH values of between 5 and 11. The SFL inhibited the bacterial growth of all the tested strains and caused little hemolysis in human erythrocytes when compared to the positive control Triton X-100.
Journal Article
Modulation of Drug Release from Natural Polymer Matrices by Response Surface Methodology: in vitro and in vivo Evaluation
by
Moin, Afrasim
,
Ashraf, Syed A
,
Allam, Ahmed N
in
Analysis
,
Animals
,
Antihypertensive Agents - chemistry
2020
The present work aimed at challenging the efficacy of natural gums, karaya and locust bean gum, as matrix-forming polymers for the formulation of sustained-release tablets of diltiazem, a model drug.
Central design composite was adopted for the formulation and optimization of tablet formulations. The two gums have been selected as independent variables. The dependent factors chosen were the amount of drug released in 1st hour (Y1), amount of drug released after 12 h (Y2), diffusion exponent (Y3), and time for half of the total drug released (T
) (Y4). Wet granulation approach was used for the formulation of tablets. FT-IR, DSC, in vitro dissolution, swelling-erosion investigations, SEM, and stability studies were carried out.
It was evident that the release pattern from the prepared formulations was significantly influenced by the quantity of gum(s) in the tablet. FT-IR and DSC results confirm drug-polymer compatibility. Polynomial equations were used for the prediction of quantitative impact of independent factors at different levels on response variables. After ANOVA analysis, the significant factors were considered for constrained optimization to get the optimized formula. The optimized formula generated by the response surface methodology was evaluated both for in vitro and in vivo properties. The optimized formula and a sustained-release marketed product were subjected to in vivo studies in rabbits and the results of the
-test demonstrated insignificant variation in pharmacokinetic parameters among the two formulations, confirming that the prepared tablet showed sustained-release profile.
The results indicated that karaya and locust bean gum can be effectively used to formulate sustained-release tablets.
Journal Article
Endogenous Synthesis of cis-9, trans-11 Conjugated Linoleic Acid in Dairy Cows Fed Fresh Pasture
by
Thomson, N.A.
,
Bauman, D.E.
,
Kay, J.K.
in
administration & dosage
,
analysis
,
Animal productions
2004
New Zealand Holstein-Friesian cows (n = 4) were used to quantify the importance of endogenous synthesis of cis-9, trans-11 conjugated linoleic acid (CLA) via Δ9-desaturase in cows fed a fresh pasture diet. The experiment was a 4×4 Latin square design with treatments arranged in a 2×2 factorial. Treatments lasted 4 d and were pasture only, pasture plus sterculic oil, pasture plus sunflower oil, and pasture plus sunflower oil plus sterculic oil. Abomasal infusion of sterculic oil inhibited Δ9-desaturase and decreased the concentration of cis-9, trans-11 CLA in milk fat by 70%. Using the changes in cis-9 10:1, cis-9 12:1 and cis-9 14:1 to correct for incomplete inhibition of Δ9-desaturase, a minimum estimate of 91% of cis-9, trans-11 CLA in milk fat was produced endogenously in cows fed fresh pasture. Dietary supplementation of a pasture diet with sunflower oil increased the proportion of long chain fatty acids in milk fat; however, the increase in vaccenic acid concentration was small (18%) and there was no increase in cis-9, trans-11 CLA concentration. Overall, results show that endogenous synthesis is responsible for more than 91% of the cis-9, trans-11 CLA secreted in milk fat of cows fed fresh pasture. However, the failure of plant oil supplements to increase the concentration of cis-9, trans-11 CLA in milk fat from pasture-fed cows requires further investigation.
Journal Article
Two Cerebrosides Isolated from the Seeds of Sterculia lychnophora and Their Neuroprotective Effect
by
Wu, Xiu-Wen
,
Wang, Ru-Feng
,
Geng, Di
in
Cell Line
,
Cell Survival - drug effects
,
cerebrosides
2013
Two cerebrosides named 1-O-b-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2-hydroxyoctadecanoyl)amido]-4,8-octadecadiene-1,3-diol (1) and soya-cerebroside I (2) were isolated from the seeds of Sterculia lychnophora for the first time. Their structures were completely characterized by spectroscopic methods including IR, MS and NMR. Compound 1 exhibited moderate neuroprotective effect against SH-SY5Y cell damage induced by hydrogen peroxide.
Journal Article
Conversion of t11t13 CLA into c9t11 CLA in Caco-2 Cells and Inhibition by Sterculic Oil
by
Mignolet, Eric
,
Beguin, Pauline
,
Perfield, James W.
in
Acids
,
Adipocytes
,
Analysis of Variance
2012
Conjugated linoleic acids (CLA), and principally c9t11 CLA, are suspected to have numerous preventive properties regarding non-infectious pathologies such as inflammatory diseases, atherosclerosis and several types of cancer. C9t11 CLA is produced in the rumen during biohydrogenation of linoleic acid, but can also be synthesized in mammalian tissues from trans-vaccenic acid (C18:1 t11) through the action of delta-9 desaturase (D9D). For several years, it is also known that c9t11 CLA can be synthesized from conjugated linolenic acids (CLnA), i.e. c9t11c13 CLnA and c9t11t13 CLnA. This study aimed at investigating to which extent and by which route c9t11 CLA can be produced from another isomer of CLA, the t11t13 CLA that is structurally very similar to c9t11t13 CLnA, in Caco-2 cells.
Caco-2 cells were incubated for 24 h with 20 µmol/l of t11t13 CLA in the absence or presence of sterculic oil used as an inhibitor of D9D. Caco-2 cells were able to convert t11t13 CLA into c9t11 CLA, and c9t11t13 CLnA was formed as an intermediate compound. In the presence of sterculic oil, the production of this intermediate was decreased by 46% and the formation of c9t11 CLA was decreased by 26%. No other metabolite was detected.
These results not only highlight the conversion of t11t13 CLA into c9t11 CLA but demonstrate also that this conversion involves first a desaturation step catalysed by D9D to produce c9t11t13 CLnA and then the action of another enzyme reducing the double bond on the Δ13 position.
Journal Article
In vivo sedative activity of methanolic extract of Stericulia villosa Roxb. leaves
2016
Background This plant is very popular ingredient of local made drinks during hot summer. After drinking this drink people feels fresh, relaxed and can enjoy sound sleep. Present study was aimed to assess the sedative properties of a plant Sterculia villosa leaves. Therefore, we tried to find out the methanolic extract from the leaves of Sterculia villosa leaves having any sedative activity or not. Methods The extract were subjected to various in vivo methods like hole cross test, open field test, elevated plus-maze (EPM) test, thiopental sodium induced sleeping time test. Diazepam was used as the standard drug. Results From the study, it is clear that the extract has excellent CNS depressant activity by reducing locomotors activity of mice in every cases of hole cross test, open field test, elevated plus-maze (EPM) test compared to the standard diazepam. In addition, the extract prolong the sleeping time (230 min) with quick onset of action (9 min) in contrast to the standard and control group. Conclusions From the present study it can be conclude that the extract posses significant a sedative property that may lead to new drug development and further investigation is necessary to understand the underlying mechanisms and to isolate the active principles.
Journal Article