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1.
Int J Biol Macromol ; 265(Pt 2): 131067, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521328

RESUMO

Researchers are consistently investigating novel and distinctive methods and materials that are compatible for human life and environmental conditions This study aimed to synthesize gold nanoparticles (ALPs-AuNPs) using for the first time an alkaline protease (ALPs) derived from Phalaris minor seed extract. A series of physicochemical techniques were used to inquire the formation, size, shape and crystalline nature of ALPs-AuNPs. The nanoparticles' ability to degrade methylene blue (MB) through photocatalysis under visible light irradiation was assessed. The findings demonstrated that ALPs-AuNPs exhibited remarkable efficacy by destroying 100 % of MB within a mere 30-minute irradiation period. In addition, the ALPs-AuNPs demonstrated remarkable effectiveness in inhibiting the growth of gram-positive (S. aureus) and gram-negative (E. coli) bacteria. The inhibition zones examined against the two bacterial strains were 23(±0.3) mm and 19(±0.4); 13(±0.3) mm and 11(±0.5) mm under light and dark conditions respectively. The ALPs-AuNPs exhibited significant antioxidant activity by effectively scavenging 88 % of stable and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. As a result, the findings demonstrated that the environmentally friendly ALPs-AuNPs showed a strong potential for MB degradation and bacterial pathogen treatment.


Assuntos
Proteínas de Bactérias , Endopeptidases , Ouro , Nanopartículas Metálicas , Humanos , Ouro/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Escherichia coli , Staphylococcus aureus/metabolismo , Bactérias , Extratos Vegetais/química
2.
Nanomaterials (Basel) ; 12(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35407197

RESUMO

Noble metal nanoparticles (NMNPs) are viable alternative green sources compared to the chemical available methods in several approach like Food, medical, biotechnology, and textile industries. The biological synthesis of platinum nanoparticles (PtNPs), as a strong photocatalytic agent, has proved as more effective and safer method. In this study, PtNPs were synthesized at four different temperatures (25 °C, 50 °C, 70 °C, and 100 °C). PtNPs synthesized at 100 °C were smaller and exhibited spherical morphology with a high degree of dispersion. A series of physicochemical characterizations were applied to investigate the synthesis, particle size, crystalline nature, and surface morphology of PtNPs. The biosynthesized PtNPs were tested for the photodegradation of methylene blue (MB) under visible light irradiations. The results showed that PtNPs exhibited remarkable photocatalytic activity by degrading 98% of MB only in 40 min. The acid phosphatase mediated PtNPs showed strong bacterial inhibition efficiency against S. aureus and E. coli. Furthermore, it showed high antioxidant activity (88%) against 1,1-diphenyl-2-picryl-hydrazil (DPPH). In conclusion, this study provided an overview of the applications of PtNPs in food chemistry, biotechnology, and textile industries for the deterioration of the natural and synthetic dyes and its potential application in the suppression of pathogenic microbes of the biological systems. Thus, it could be used as a novel approach in the food microbiology, biomedical and environmental applications.

3.
Int J Biol Macromol ; 168: 195-204, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33309659

RESUMO

Herein for the first time a novel acid phosphatase from the seedlings of Cichorium intybus was purified to homogeneity by using various chromatographic techniques (salt precipitation, ion exchange, size exclusion and affinity chromatography) and thermodynamically characterized. The molecular mass of purified enzyme (66 kDa) was determined by SDS-PAGE under denaturing and non-denaturing conditions and by gel-filtration confirmed as dimer of molecular mass 130 kDa. The Michaelis-Menten (Km) constant for -p-NPP (0.3 mM) and (7.6 µmol/min/mg) Vmax. The enzyme was competitively inhibited by phosphate, molybdate and vanadate. Phenyl phosphate, ɑ and ß-glycero-phosphate and-p-NPP were found to be good substrate. When temperature increased from (55 °C to 75 °C), the deactivation rate constant (kd) was increased (0.1 to 4.6 min-1) and half- life was decreased from 630 min to 15 min. Various thermal denaturation parameters; change in enthalpy (ΔH°), change in entropy (ΔS°) and change in free energy (ΔG°) were found 121.93 KJ·mol-1, 72.45 KJ·mol-1 and 98.08 KJ·mol-1 respectively, confirming that acid phosphatase undergoes a significant process of unfolding during deactivation. The biochemical properties of acid phosphatase from C. intybus on the behalf of biological activity and its relationship to pH variations, thermal deactivation and kinetics parameters provide an insight into its novel features.


Assuntos
Fosfatase Ácida/química , Fosfatase Ácida/isolamento & purificação , Cichorium intybus/química , Cichorium intybus/enzimologia , Cichorium intybus/metabolismo , Cromatografia em Gel/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Fosfatos , Plântula/química , Temperatura , Termodinâmica
4.
Mater Sci Eng C Mater Biol Appl ; 116: 111278, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806276

RESUMO

A novel and simple strategy was designed for the synthesis of an unmodified gum arabic (GA) and acrylic acid (AA) based polymer hydrogels using Fe3+ as a physical cross-linking agent. The hydrogels showed a high mechanical strength, self-sustainability and self-healing ability, which depends on the content of GA and Fe3+ in the composition. The fracture stress increased from 0.23 to 0.841 MPa and a decrease in self-healing from 53 to 34% was observed by increasing the GA amount from 12 to 50% respectively. The self-healing performance of the hydrogels enhanced with the existence of the Fe3+ amount on the interface. Therefore, the 3% addition of Fe3+, increased the self-healing ability of up to 70%. Furthermore, the hydrogels also showed an excellent fatigue resistance up to 20 cycles without any rapture and can beard a load of 2.5 kg for a very long time. After 4 min of resting time, the percent recovery in dissipated energy reaching a high value of 95%, indicating the excellent fatigue resistance performance of the hydrogels. The hydrogels contain 3-5% of water at normal conditions and confirm its environmental stability. This work provides a new direction for the synthesis of unmodified GA based physically cross-linked polymer hydrogels systems and can be applied in bioengineering and robotic science in the future.


Assuntos
Goma Arábica , Hidrogéis , Acrilatos , Polímeros
5.
Int J Biol Macromol ; 165(Pt A): 1475-1481, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33058972

RESUMO

Herein acid phosphatase isoenzyme was extracted from the C. murale seedlings. The purification was accomplished by chromatographic techniques and passing through DEAE-cellulose and Sephadex G-100 column. The specific activity of acid phosphatase 5.75 U/mg of protein was obtained with 66 purification fold 15.8% yield and molecular mass was 29 kDa with very faint bands corresponding to 18 kDa and 14 kDa. The maximal activity at pH 5.0 and 50 °C best illustrated by first order kinetics. When temperature was raised (55 °C to 75 °C), the deactivation rate constant was increased from 0.001 to 0.014 min-1, while half-life was decreased from 693 to 49 min-1. The results of activity collected at different temperature were then used to estimate, activation energy of hydrolysis reaction (Ea = 47.59 kJmol-1). A high Z-value (18.86 °C min-1) was obtained indicating a less sensitivity towards temperatures. The residual activity examinations were carried out from 55 °C to 75 °C and assessing the Deactivation Energy (Ed 116.39 kJmol-1), Enthalpy change (ΔH° 113.55kJmol-1), Entropy change (ΔS° 110.33kJmol-1) and change in Gibbs free energy (ΔG° 10.02 kJmol-1). Taken together, thermodynamic parameters confirm the high stability of enzyme and show potential commercial applicability.


Assuntos
Fosfatase Ácida/química , Chenopodium/química , Cinética , Extratos Vegetais/química , Fosfatase Ácida/genética , Entropia , Estabilidade Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Peso Molecular , Extratos Vegetais/farmacologia , Plântula/química , Temperatura , Termodinâmica
6.
RSC Adv ; 9(32): 18565-18577, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35515230

RESUMO

A novel zwitterionic superabsorbent polymer hydrogel [ZI-SAH] was synthesized by free radical polymerization and used for the removal of crystal violet (CV) and congo red (CR) from an aqueous medium. ZI-SAH was composed of pH-sensitive monomers poly(3-acrylamidopropyl) trimethylammoniumchloride (APTMACl) and 2-acrylamido-2-methylpropanesulphonic acid (AAMPSA). The hydrogel was characterized by SEM and FT-IR spectroscopy, while the visco-elastic behavior was studied using rheological tests. The hydrogel showed a point of zero charge (PZC) at pH 7.2 and high swelling abilities of 3715% at pH 9 and 3112% at pH 5. The cationic crystal violet (CV) and anionic congo red (CR) dyes were employed to investigate the removal ability of ZI-SAH using the batch adsorption method. The materials became more selective towards oppositely charged dyes at pH 5 and 9. The effects of parameters such as contact time, initial concentration of dyes, pH, ZI-SAH dosage and ionic strength on the removal performance were investigated. A kinetic study was carried out via Lagergren pseudo first order and pseudo second order kinetics. The adsorption efficiencies of ZI-SAH were 13.6 mg g-1 for CV and 9.07 mg g-1 for CR with % removal values of 97 and 89, respectively. The thermodynamic parameters, namely, ΔG°, ΔH° and ΔS° were determined, and the negative value of free energy showed that the process of adsorption was spontaneous. ZI-SAH was recycled and reused in five consecutive cycles with removal efficiency > 75%.

7.
J Ethnopharmacol ; 171: 273-9, 2015 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-26055343

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In the study area, the traditional knowledge regarding the uses of local wild medicinal plants for treating diseases of domestic animals and birds is totally in the custody of elders of the existing community. The young ones are not much aware about such important practices. AIM OF THE STUDY: The main aim of the study was to document and to release this knowledge from the custody of elders and share with the community. MATERIALS AND METHODS: Total 115 people between 20 and 80 years of age were interviewed and information was collected through semi-structured questionnaires. The data obtained were quantitatively analyzed using the use value (UV) formula. The collected specimens were pressed, dried, preserved, mounted on Herbarium sheets, identified properly and were submitted in the Herbarium, Department of Botany, Hazara University, Mansehra, Pakistan. RESULTS: With the co-ordination and cooperation of the local people, 46 plant species of 42 genera belonging to 31 families were collected, 3 were monocotyledons while 43 plant species belonged to dicotyledonae class. Considering taxonomic characteristics, it was confirmed that 12 trees, 10 shrubs and 22 herbs were commonly used by the local people in ethno veterinary practices. Two plants like Cistanche tubulosa and Cuscuta reflexa from family Orobanchaceae and family Cuscutaceae respectively lack chlorophyll and are parasites on host plants like Doedonia, Ziziphus, Calligonum and Calotropis. The powder of both plants showed great ethno veterinary value. The parts of 46 plant species commonly used for ethno veterinary practices were whole plants (32.60%), leaves (26.08%), fruits (17.39%), stems (13.04%) and roots (10.86%). Medicinal plants were administered through various routes i.e. oral (78.26%), skin (17.21%) and smoke (4.34%). CONCLUSION: The traditional knowledge of local plants of ethno veterinary values is mainly possessed by elders and transmitted from generation to generation with chances of elimination of such traditional knowledge due to less awareness. The present study was designed to document this ethno veterinary related knowledge and to share it with community members for use in future.


Assuntos
Fitoterapia/veterinária , Preparações de Plantas/uso terapêutico , Plantas Medicinais , Drogas Veterinárias/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Etnofarmacologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Inquéritos e Questionários , Adulto Jovem
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