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531.
《Arabian Journal of Chemistry》2023,16(2):104474
IntroductionScientific evidence about biological profile of natural products can support their traditional uses. The current work was aimed to assess phytochemical and biological profile of nine medicinal plants collected from Herbalists.MethodsExtracts prepared in different solvents were subjected to phytochemical, antioxidant, enzyme inhibitory, cytotoxic, and antimicrobial activities. Reverse phase-high performance liquid chromatography (RP-HPLC) analysis was performed for the quantification of polyphenols.ResultsResults showed methanol extract (M) being potent as compared to others. Gentian lutea M showed maximum extract recovery (15.00 ± 0.11 % w/w) and TFC (30.82 ± 0.21 μg QE/mg extract). Nigella sativa M displayed highest TPC (44.99 ± 0.43 μg GAE/mg extract) and TAC (334.72 ± 0.35 μg AAE/ mg extract). Results showed noteworthy quantities of vanillic acid, rutin, kaempferol, emodin in ethyl acetate (EA) and methanol (M) extracts of plants assessed by RP-HPLC. Gentisic acid was highest (11.75 µg/mg extract) in T. arjuna M extract. Similarly, maximum %FRSA (82.28 ± 0.03 %) and TRP (160.40 ± 0.38 μg AAE/ mg extract) were depicted by Terminalia chebula and Chamomilla recutita, respectively. Moreover, Mentha longifolia and G. lutea M demonstrated noteworthy (p < 0.05) antibacterial activity against Staphylococcus aureus (14 ± 0.7 mm) and Klebsiella pneumoniae (12 ± 0.3 mm), respectively. Curcuma amada, C. recutita, Murraya koenigii and G. lutea M had significant α-glucosidase activity. Another good solvent for extraction was ethyl acetate (EA), whose extracts were secondary to methanol in producing significant biological profile. For example, EA of N. sativa (TPC: 1.46 ± 0.45 µg GAE/ mg extract), G. lutea (TRP: 160.33 ± 0.52 μg AAE/mg extract: ZOI of 12 ± 0.5 mm in K. pneumoniae) and Mormodica charantia (α-amylase inhibition: 39.5 ± 0.10 %) showed significant bioactivities. All extracts displayed mild antifungal protein kinase inhibition activities and were significantly (greater than80 %: p < 0.05) cytotoxic to brine shrimps with negligible hemolytic activity.ConclusionBriefly, variable polarity solvent extracts of studied plants will be processed for isolation of antioxidant, cytotoxic, carbohydrate enzyme inhibitory and antibacterial compounds. 相似文献
532.
《Arabian Journal of Chemistry》2023,16(4):104552
Heavy metals (HMs), pollution of major environmental matrices and its attendant effects on human health and the environment, continue to generate huge scientific interest, particularly in monitoring and detection. Herein, the optical property of carboxymethyl cellulose stabilized silver nanoparticles (CMC-AgNPs), supported with ascorbic acid, is exploited as a colorimetric probe for the detection of toxic Au3+ ion in solution. The as-synthesized CMC-AgNPs showed sharp absorption maximum at 403 nm, with sparkling yellow color and average particles size distribution less than 10 nm. It was further characterized using ATR-FTIR, TEM, FESEM/EDS, XRD and DLS/zeta potential analyzer. Au3+ ion detection strategy involves the addition of ascorbic acid (AA) to a pH adjusted CMC-AgNPs, followed by the analyte addition. AA would facilitate the reduction of Au3+ on CMC-AgNPs (seed), with resultant color perturbations from light yellow to yellow, orange, ruby red and purple red, under 8 min incubation, at room temperature (RT). The CMC-AgNPs could also serve as a catalyst, by promoting AA mediated reduction of Au3+, in-situ. Moreover, we propose, that the color and the absorption spectra change is attributed to the deposition of gold nanoparticles (AuNPs), on the CMC-AgNPs/AA probe, to form (CMC-Ag@Au) nanostructures, depending on the analyte concentration. Absorbance ratio (A540/A403) showed good linearity with Au3+ concentration from 0.25 to 100.0 µM, and an estimated LOD of 0.061 µM. The assay was applied to Au3+ detection in environmental wastewater sample, showing satisfactory real sample detection potentiality. 相似文献
533.
《Arabian Journal of Chemistry》2023,16(4):104597
The water-soluble polysaccharides from plants have attracted ever-increasing attention in the field of food and drug due to their various activities and low toxicity. CBP50-1, as a purified fraction of polysaccharide from the rhizome of Cibotium barometz (CBP), mainly consisted of glucose (55.45%) and xylose (25.27%). CBP50-1 showed excellent antioxidant activity for scavenging 2,2?Diphenyl?1?picryl?hydrazy (DPPH) radical and hydroxyl radical, further inhibiting lipid peroxidation. CBP50-1 significantly improved the survival rate of Caenorhabditis elegans under thermal and oxidative stress. Furthermore, CBP50-1 reduced the paralysis and oxidative damage induced by amyloid-beta (Aβ) and increased the antioxidant enzyme activity in Alzheimer’s disease (AD) model C. elegans CL4176 through c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) signal pathway. Thus, CBP50-1 had a potential application in health industries. 相似文献