84 research outputs found

    Comparison of ASE with in-cell cleanup and the QuEChERS sample preparation methods for the analysis of pesticide residues in tea

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    The aim of the present work was to compare and choose the best method to extract incurred pesticide residues from green tea. Accelerated solvent extraction (ASE) with in-cell cleanup and the quick, easy, cheap, effective rugged and safe (QuEChERS) methods were tested on green tea samples with incurred beta-endosulfan pesticide. The extracts were analyzed by GC-MS/MS and the recovery and the precision of both methods were compared. The average recovery using ASE with the in-cell cleanup method was in the range of 89 to 92% which is better than that obtained using a QuEChERS method. Both the ASE with in-cell cleanup and the QuEChERS methods provided good precision with RSDs in the range of 12 to 15% and 17 to 18%, respectively. This finding indicates that the ASE method with the in-cell cleanup is more suitable for the accurate determination of pesticides incurred in tea

    Antioxidant, antityrosinase, anticholinesterase, and nitric oxide inhibition activities of three Malaysian Macaranga species.

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    The methanol extracts of three Macaranga species (M. denticulata, M. pruinosa, and M. gigantea) were screened to evaluate their total phenolic contents and activities as cholinesterase inhibitors, nitric oxide (NO) production inhibitors, tyrosinase inhibitors, and antioxidants. The bark of M. denticulata showed the highest total phenolic content (2682 mg gallic acid equivalent (GAE)/100 g) and free radical scavenging activity (IC50 = 0.063 mg/mL). All of the samples inhibited linoleic acid peroxidation by greater than 80%, with the leaves of M. gigantea exhibiting the highest inhibition of 92.21%. Most of the samples exhibited significant antioxidant potential. The bark of M. denticulata and the leaves of both M. pruinosa and M. gigantea exhibited greater than 50% tyrosinase inhibition, with the bark of M. denticulata having the highest percentage of inhibition (68.7%). The bark and leaves of M. denticulata exhibited greater than 50% inhibition (73.82% and 54.50%, resp.) of the acetylcholinesterase enzyme (AChE), while none of the samples showed any significant inhibition of butyrylcholinesterase (BChE). Only the bark of M. denticulata and M. gigantea displayed greater than 50% inhibition of nitric oxide production in cells (81.79% and 56.51%, resp.). These bioactivities indicate that some Macaranga spp. have therapeutic potential in medicinal research

    Cosmos caudatus as a potential source of polyphenolic compounds : optimisation of oven drying conditions and characterisation of its functional properties.

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    The aim of the study was to analyze the influence of oven thermal processing of Cosmos caudatus on the total polyphenolic content (TPC) and antioxidant capacity (DPPH) of two different solvent extracts (80% methanol, and 80% ethanol). Sonication was used to extract bioactive compounds from this herb. The results showed that the optimised conditions for the oven drying method for 80% methanol and 80% ethanol were 44.5 °C for 4 h with an IC50 of 0.045 mg/mL and 43.12 °C for 4.05 h with an IC50 of 0.055 mg/mL, respectively. The predicted values for TPC under the optimised conditions for 80% methanol and 80% ethanol were 16.5 and15.8 mg GAE/100 g DW, respectively. The results obtained from this study demonstrate that Cosmos caudatus can be used as a potential source of antioxidants for food and medicinal applications

    Antioxidant and α-glucosidase inhibitory activities of the leaf and stem of selected traditional medicinal plants

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    The study was aimed to determine the antioxidant and α-glucosidase inhibition activities of the stem and leaf of five different traditional medicinal plants. The studied plants exhibited varied antioxidant and α-glucosidase inhibition activities. The antioxidant activities of the plants were determined through their free radical scavenging capabilities using DPPH assay. The most potent antioxidant activity was demonstrated by Neptunia oleracea with an IC50 of 35.45 and 29.72 μg/mL for leaf and stem, respectively. For α-glucosidase inhibition activity, Neptunia oleracea exhibited potential α-glucosidase inhibition activity with IC50 value of 19.09 and 19.74 μg/mL for leaf and stem, respectively. The highest total phenolic content (TPC) was also marked in Neptunia oleracea leaf and stem with value of 40.88 and 21.21 mg GAE/g dry weight, respectively. The results also showed that Strobilanthes crispus collected from two different locations possessed different levels of phenolic content, antioxidant and α-glucosidase inhibition activities. The study revealed that phenolic compounds could be the main contributors to the antioxidant and α-glucosidase inhibition activities with R values of 78.9 and 67.4%, respectively. In addition, antioxidant and α-glucosidase were positively correlated (R = 81.9%). Neptunia oleracea could be suggested as a potential natural source of antioxidant and antidiabetic compounds that can be used for the prevention or treatment of diabetes

    Physicochemical and Organoleptic Analysis of Tomato Irrigated with fish farms water; at URERMS-ADRAR. Algeria

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    The objective of the developed system is to encourage efficient water management practices that optimize the usage of water by keeping crop health and yield intact through the implementation of an automated irrigation system. The study aimed to determine the impact of irrigation by fish farming on growth rates and concentrations of macro- and micronutrients in tomatoes. Results indicated that irrigation with fish farm effluent significantly increased and effluent water, depending on its composition to feed the fish, can supply nutrients and increase the concentrations of these elements in tomatoes irrigated with this water with a refractive index = 1.3391 and a calorie value of 19.927 Calorie in the first sampling and 16.696 calories in the second sampling for 100 g for the year 2021 and for the year 2022 we have a refractive index = 1.3495 and a calorie value of 20.66 Calorie for 100 g. Here we show for the first time that is more than the standard norm (Cotte.2000) which is 18 Calories. Also, after carrying out microbiological analyzes, there is a total absence of pathogenic bacteria, as well as the organoleptic parameters are heading in the right direction where tomatoes irrigated by fish farming water is concentrated compared to the tomatoes irrigated by normal fresh water with Light red of 53 %, Cooked acid of 47 %, spherical form of 94 % and a pleasant smell of 88 %. Therefore, using fish farm effluent in irrigation provides water requirements for plants and also can improve the availability of nutrient elements for tomatoes

    Comparative Metabolite Fingerprinting of Four Different Cinnamon Species Analyzed via UPLC–MS and GC–MS and Chemometric Tools

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    The present study aimed to assess metabolites heterogeneity among four major Cinnamomum species, including true cinnamon (Cinnamomum verum) and less explored species (C. cassia, C. iners, and C. tamala). UPLC-MS led to the annotation of 74 secondary metabolites belonging to different classes, including phenolic acids, tannins, flavonoids, and lignans. A new proanthocyanidin was identified for the first time in C. tamala, along with several glycosylated flavonoid and dicarboxylic fatty acids reported for the first time in cinnamon. Multivariate data analyses revealed, for cinnamates, an abundance in C. verum versus procyandins, dihydro-coumaroylglycosides, and coumarin in C. cassia. A total of 51 primary metabolites were detected using GC-MS analysis encompassing different classes, viz. sugars, fatty acids, and sugar alcohols, with true cinnamon from Malaysia suggested as a good sugar source for diabetic patients. Glycerol in C. tamala, erythritol in C. iners, and glucose and fructose in C. verum from Malaysia were major metabolites contributing to the discrimination among species

    Comparison of partial least squares and random forests for evaluating relationship between phenolics and bioactivities of Neptunia oleracea

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    Background: Neptunia oleracea is a plant consumed as a vegetable and which has been used as a folk remedy for several diseases. Herein, two regression models (partial least squares, PLS; and random forest, RF) in a metabolomics approach were compared and applied to the evaluation of the relationship between phenolics and bioactivities of N. oleracea. In addition, the effects of different extraction conditions on the phenolic constituents were assessed by pattern recognition analysis. Results: Comparison of the PLS and RF showed that RF exhibited poorer generalization and hence poorer predictive performance. Both the regression coefficient of PLS and the variable importance of RF revealed that quercetin and kaempferol derivatives, caffeic acid and vitexin-2-O-rhamnoside were significant towards the tested bioactivities. Furthermore, principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) results showed that sonication and absolute ethanol are the preferable extraction method and ethanol ratio, respectively, to produce N. oleracea extracts with high phenolic levels and therefore high DPPH scavenging and α-glucosidase inhibitory activities. Conclusion: Both PLS and RF are useful regression models in metabolomics studies. This work provides insight into the performance of different multivariate data analysis tools and the effects of different extraction conditions on the extraction of desired phenolics from plants

    Effects of different drying methods and storage time on free radical scavenging activity and total phenolic content of Cosmos caudatus

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    The present study was conducted to determine the effect of air (AD), oven (OD) and freeze drying (FD) on the free radical scavenging activity and total phenolic content (TPC) of Cosmos caudatus and the effect of storage time by the comparison with a fresh sample (FS). Among the three drying methods that were used, AD resulted in the highest free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC50 = 0.0223 mg/mL) and total phenolic content (27.4 g GAE/100 g), whereas OD produced the lowest scavenging activity and TPC value. After three months of storage, the dried samples showed a high and consistent free radical scavenging activity when compared to stored fresh material. The drying methods could preserve the quality of C. caudatus during storage and the stability of its bioactive components can be maintained

    Effect of different drying methods and solvent ratios on biological activities of Phyllanthus acidus extracts

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    The main purpose of this study was to evaluate the antioxidant and α-glucosidase inhibitory activities of Phyllanthus acidus. The P. acidus fruits were dried using three different methods, namely oven (OD), air (AD) and freeze (FD) dryings and extracted with ethanol at different ratios (50 and 100%). The proximate analysis and total phenolic content (TPC) as well as free radical scavenging and α-glucosidase inhibitory activities were determined. The proximate analysis of P. acidus fruit indicated that all the dried samples contained potential nutrient contents. The highest TPC value, α-glucosidase inhibitory and antioxidant activities were observed for 50% ethanolic extract from OD method with TPC value of 28.39 mg GAE/g dried extract, IC50 value of 12.394 μg/mL and 64.17% inhibition, respectively. The study revealed that phenolic compounds could be the main contributors to the antioxidant and α-glucosidase inhibitory activities based on the Pearson correlation coefficients with R values of 95.0 and 73.8%, respectively. The study could provide scientific evidence for some folk uses in the treatment of diseases related to the production of reactive oxygen species and oxidative stress

    Chemical profile of xanthine oxidase inhibitor fraction of Persicaria hydropiper

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    Persicaria hydropiper, locally known as kesum, is an herb belongs to the family Polygonaceae. It has been used widely in many countries as food flavoring and possesses a wide range of medicinal values. The total phenolic content and xanthine oxidase inhibitory activity of the methanolic extract of P. hydropiper and fractions were determined spectrophotometrically. The butanol fraction was found to contain high phenolic content and was able to inhibit xanthine oxidase activity. Online profiling using liquid chromatography coupled with electrospray ionisation spectrometry (LC-ESIMS/MS) has revealed ten constituents in this active fraction. The major components were flavonoid derivatives and flavonoid sulphates, which were confirmed by comparison with an authentic standards as well as their MS/MS fragmentation patterns and UV spectra
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