Papaya Peel Extract Research Articles

Greener Biogenic Approach for the Synthesis of Palladium Nanoparticles Using Papaya Peel: An Eco-Friendly Catalyst for C-C Coupling Reaction.

The development of a green and sustainable synthetic methodology still remains a challenge across the globe. Encouraging the prevailing challenge, herein, we have synthesized Pd nanoparticles (Pd NPs) in a green and environmentally viable route, using the extract of waste papaya peel without the assistance of any reducing agents, high-temperature calcination, and reduction procedures. The biomolecules present in the waste papaya peel extract reduced Pd(II) to nanosize Pd(0) in a one-pot green and sustainable process. As a catalyst, the new Pd NPs offer a simple and efficient methodology in direct Suzuki–Miyaura and Sonogashira coupling with excellent yields under mild reaction conditions.

Carica papaya peel mediated synthesis of silver nanoparticles and its antibacterial activity against human pathogens

Metallic nanoparticles are traditionally synthesized by wet chemical techniques, in which the chemicals used are quite often toxic and flammable. Ripe carica papaya peel is found to be a suitable source for green synthesis of silver nanoparticles. In the present work, a cost effective and environmental friendly technique for the green synthesis of silver nanoparticles from 1 mM silver nitrate (AgNO3 ) solution through the extract of ripe Carica papaya peel of various concentrations (5 ml, 10 ml, 15 ml, 20 ml, 25 ml) is described. The synthesized silver nanoparticles are characterized by using the UV–vis absorption spectroscopy, FT-IR, XRD, SEM and TEM. The formation of silver nanoparticles is confirmed by surface plasmon resonance, determined by UV–vis spectra at 400–435 nm. The shift in the absorption bands and variation in the calculated optical band gaps for the various concentrations of papaya peels extracts are also observed. The FT-IR spectra reveal that an increase in the concentration of the papaya peel extract shifts the bands to higher wavelengths. The average crystallite size for various concentrations of papaya peel extract is observed from XRD spectral analysis and is found to be around 16–20 nm, which is in good agreement with the TEM analysis. The SEM analysis shows the spherical structure of the silver nanoparticles with some agglomeration for higher concentrations of papaya peel extract. The synthesized silver nanoparticles show good antibacterial activity against human pathogens such as Escherichia coli and Staphylococcus aureus and it has many medical applications.

Papaya peel extract as potential corrosion inhibitor for Aluminium alloy in 1 M HCl: Electrochemical and quantum chemical study

Abstract This paper deals with the corrosion inhibition effect of Papaya peel extract (PPE) on Aluminium alloy (AA) in 1 M HCl. The corrosion tests were performed by using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques (PDP). Maximum inhibition efficiency observed is 95.5% and 98.1% from EIS plot and PDP studies at higher concentration (2.0 g L −1 ) of PPE. Potentiodynamic polarization result shows mainly the cathodic type inhibition for PPE. Surface morphology of AA is carried by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Quantum chemical study is complemented well with the experimental findings of the corrosion inhibition.

Biosynthesis of AgNPs using Carica Papaya peel extract and evaluation of its antioxidant and antimicrobial activities

Waste fruit peel mediated synthesis of silver nanoparticles (AgNPs) is a green chemistry approach that links nanotechnology and biotechnology. Using biological medium such as peel extract for the biosynthesis of nanoparticles is an ecofriendly and emerging scientific trend. With this back drop the present study focused on the biosynthesis of AgNPs using Carica Papaya peel extract (CPPE) and evaluation of its antimicrobial potentials of the nanoparticles against different human pathogens and to investigate the free radical scavenging activity. Water soluble antioxidant constituents present in Carica Papaya peel extract were mainly responsible for the reduction of silver ions to nanosized Ag particles. UV–vis spectral analysis shows surface plasmon resonance band at 430nm. The presence of active proteins and phenolic groups present in the biomass before and after reduction was identified by Fourier transform infrared spectroscopy. X-ray diffraction study shows the average size of the silver nanoparticles is in the range of 28nm, as well as revealed their face centered cubic structure. Atomic force microscope image gives the 3D topological characteristic of silver nanoparticles and the particle size ranges from 10 to 30nm. The average particle size distribution of silver nanoparticles is 161nm (Dynamic light scattering) and the corresponding average zeta potential value is −20.5mV, suggesting higher stability of silver nanoparticles. Biologically synthesized nanoparticles efficiently inhibited pathogenic organisms both gram-positive and gram-negative bacteria. The biosynthesized nanoparticles might serve as a potent antioxidant as revealed by DPPH and ABTS+assay.

Antioxidant and Apoptotic Activity of Papaya Peel Extracts in HepG2 Cells

Papaya peels (PP) are discarded after consuming the fruit. However, they contain antioxidants. Oxidative damage caused by free radicals has major implications in many chronic diseases. The objective of this study was to determine in-vitro antioxidant and apoptotic activity of PP extracts. Modulation of endogenous glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), cyclo-oxygenase-2 (COX-2), caspase-3 activities and DNA fragmentation by PP extracts in HepG2 cells were evaluated. Gallic acid (18.06 μg/g), caffeic acid (29.28 μg/g), p-coumaric acid (38.16 μg/g), ferulic acid (95.46 μg/g) and quercetin (3.17 μg/g) were the major polyphenols quantified in PP extracts. In-vitro antioxidant capacity of PP was determined by ferric reducing antioxidant potential (31.86 μM Fe+2/g), trolox equivalent antioxidant capacity (14.56 mM trolox equivalents (TE)/g), oxygen radical scavenging activity (30.88 mM TE/g) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability (IC50-8.33 mg/ml). Induction of oxidative stress significantly (p ≤ 0.05) lowered SOD, CAT, GPx, GR activities and GSH levels by 3.1, 1.46, 2.87, 1.34 and 1.32 folds compared to control respectively. However, treating cells with PP extracts significantly (p ≤ 0.05) enhanced SOD, CAT, GPx, GR activities and GSH compared to oxidative stress induced cells. Treating cells with PP extracts significantly (p ≤ 0.05) lowered COX-2 activity, enhanced caspase-3 activity and induced DNA fragmentation, indicating that PP extracts caused cell death by apoptosis. In conclusion, anti-cancer properties of PP extracts may be due to the synergistic effect of free radical scavenging ability, induction antioxidant enzymes and by inducing apoptosis.

Cytotoxic potential of few Indian fruit peels through 3-(4,5-dimethylthiazol-yl)-2,5-diphenyltetrazolium bromide assay on HepG2 cells.

Objective:To investigate in vitro anticancer activity of a few Indian fruit peels through 3-(4,5-dimethylthiazol-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against HepG2 cells.Materials and Methods:Hydroalcoholic extracts were prepared of five fruit peels, i.e., banana, lemon, guava, orange, and papaya by maceration and thereafter subjected for MTT assay to evaluate anticancer potential on HepG2 cells. Plant extract showed best activity was further fractionated with petroleum ether, chloroform, and ethyl acetate successively and screened again. Phytochemical analysis was then carried out to find out responsible components for the observed activity.Results:Out of the 40 samples from five fruit peel extracts with rich folklore usage, papaya extract showed maximum activity with least inhibitory concentration50 (IC50) value of 18.5 μg/ml. Further analysis after fractionation of the papaya peel extract, aqueous fraction showed the maximum inhibitory activity with least IC50 value of 17.3 μg/ml. Phytochemical analysis of the aqueous fraction of papaya peel extract revealed the presence of flavonoids and glycosides. Total flavonoid content found to be 72.25 mg/g.Conclusion:Papaya fruit extract demonstrated the best activity against MTT assay which may be due to the presence of flavonoids.

Catalytic Reduction of 4-Nitrophenol Using Biogenic Silver Nanoparticles Derived from Papaya (Carica papaya) Peel extract

A facile and green method is described for the synthesis of Silver (Ag) nanoparticles (NPs) from the extract of Papaya Peel as capping and reducing agent. The green synthesized Ag NPs were characterized by diverse techniques such as powder X-ray diffraction (XRD), UV-visible, Fourier transform-infrared spectroscopy (FTIR) and Transmission electron microscopy (TEM) coupled with X-ray energy dispersive spectroscopy (EDS) techniques. These clearly reveal that the structure of the synthesized silver nanoparticles was face centered cubic. The nanoparticles obtained from Papaya Peel extract were spherical shape with an average diameter of 3-5 nm. Furthermore, the catalytic activity of synthesized Ag NPs in the reduction of 4-nitrophenol (4-NP) was studied by UVvis absorption spectroscopy. The synthesized Ag NPs have a good catalytic activity on the reduction of 4-nitrophenol (4-NP) by Papaya Peel extract which is confirmed by the decrease in absorbance maximum values of 4-nitrophenol (4-NP) with respect to time using UV-vis absorption spectroscopy. An efficient reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of Ag NPs and NaBH4 was observed and was found to depend upon the nanoparticle size or the peel extract concentration used for synthesis.

Catalytic Reduction of 4-Nitrophenol Using Biogenic Silver Nanoparticles Derived from Papaya (Carica papaya) Peel extract

Catalytic Reduction of 4-Nitrophenol Using Biogenic Silver Nanoparticles Derived from Papaya (Carica papaya) Peel extract

Amelioration of azoxymethane induced-carcinogenesis by reducing oxidative stress in rat colon by natural extracts

BackgroundAzoxymethane (AOM) is a potent carcinogenic agent commonly used to induce colon cancer in rats; the cytotoxicity of AOM is considered to mediate oxidative stress. This study investigated the chemopreventive effect of three natural extracts [pomegranate peel extract (PomPE), papaya peel extract (PapPE) and seaweed extract (SE)] against AOM-induced oxidative stress and carcinogenesis in rat colon.MethodsEighty Sprague–Dawley rats (aged 4 weeks) were randomly divided into 8 groups (10 rats/group). Control group was fed a basal diet; AOM-treated group was fed a basal diet and received AOM intraperitonial injections for two weeks at a dose of 15 mg/kg bodyweight, whereas the other six groups were received oral supplementation of PomPE, PapPE or SE, in the presence or absence of AOM injection. All animals were continuously fed ad-libitum until aged 16 weeks, then all rats were sacrificed and the colon tissues were examined microscopically for pathological changes and aberrant crypt foci (ACF) development, genotoxicity (induced micronuclei (MN) cells enumeration), and glutathione and lipid peroxidation.ResultsOur results showed that AOM-induced ACF development and pathological changes in the colonic mucosal tissues, increased bone marrow MN cells and oxidative stress (glutathione depletion, lipid peroxidation) in rat colonic cells. The concomitant treatment of AOM with PomPE, PapPE or SE significantly ameliorated the cytotoxic effects of AOM.ConclusionsThe results of this study provide in-vivo evidence that PomPE, PapPE and SE reduced the AOM-induced colon cancer in rats, through their potent anti-oxidant activities.

Attraction of Female Papaya Fruit Fly (Diptera: Tephritidae) to Male Pheromone and Host Fruit

A green papaya fruit or an extract of green papaya fruit peel increased unmated female papaya fruit fly (Toxotrypana curvicauda Gerstaecker) attraction to male pheromone at low pheromone release rates. Green papaya peel extract also increased mated female attraction to male pheromone, but only at the highest pheromone release rates tested. Such enhanced responses may aid the ability of females to locate hosts by responding to a combination of male pheromone released from host fruit and fruit odor.