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1.
Int J Pharm ; 657: 124190, 2024 May 25.
Article En | MEDLINE | ID: mdl-38701910

Lubricants are essential for most tablet formulations as they assist powder flow, prevent adhesion to tableting tools and facilitate tablet ejection. Magnesium stearate (MgSt) is an effective lubricant but may compromise tablet strength and disintegratability. In the design of orodispersible tablets, tablet strength and disintegratability are critical attributes of the dosage form. Hence, this study aimed to conduct an in-depth comparative study of MgSt with alternative lubricants, namely sodium lauryl sulphate (SLS), stearic acid (SA) and hydrogenated castor oil (HCO), for their effects on the tableting process as well as tablet properties. Powder blends were prepared with lactose, sodium starch glycolate or crospovidone as the disintegrant, and a lubricant at different concentrations. Angle of repose was determined for the mixtures. Comparative evaluation was carried out based on the ejection force, tensile strength, liquid penetration and disintegratability of the tablets produced. As the lubricant concentration increased, powder flow and tablet ejection improved. The lubrication efficiency generally decreased as follows: MgSt > HCO > SA > SLS. Despite its superior lubrication efficacy, MgSt is the only lubricant of four evaluated that reduced tablet tensile strength. Tablet disintegration time was strongly determined by tensile strength and liquid penetration, which were in turn affected by the lubricant type and concentration. All the above factors should be taken into consideration when deciding the type and concentration of lubricant for an orodispersible tablet formulation.


Excipients , Lubricants , Stearic Acids , Tablets , Tensile Strength , Lubricants/chemistry , Stearic Acids/chemistry , Excipients/chemistry , Drug Compounding/methods , Powders/chemistry , Sodium Dodecyl Sulfate/chemistry , Castor Oil/chemistry , Povidone/chemistry , Starch/chemistry , Starch/analogs & derivatives , Lactose/chemistry , Administration, Oral , Solubility , Chemistry, Pharmaceutical/methods
2.
Sci Rep ; 14(1): 11161, 2024 05 15.
Article En | MEDLINE | ID: mdl-38750054

Biodegradable plastics are those subjected easily to a degradation process, in which they can be decomposed after disposal in the environment through microbial activity. 30 bioplastic film formulations based only on chitosan film were used in the current investigation as a positive control together with chitosan film recovered from chitin-waste of locally obtained Aristeus antennatus. Additionally, castor oil was used as a plasticizer. While the yield of chitosan was 18% with 7.65% moisture content and 32.27% ash in the shells, the isolated chitin had a degree of deacetylation (DD) of 86%. The synthesized bioplastic films were characterized via numerous criteria. Firstly, the swelling capacity of these biofilms recorded relatively high percentages compared to polypropylene as synthetic plastic. Noticeably, the FTIR profiles, besides DSC, TGA, and XRD, confirmed the acceptable characteristics of these biofilms. In addition, their SEM illustrated the homogeneity and continuity with a few straps of the chitosan film and showed the homogeneous mixes of chitosan and castor oil with 5 and 20%. Moreover, data detected the antibacterial activity of different bioplastic formulas against some common bacterial pathogens (Enterococcus feacalis, Kelbsiella pnumina, Bacillus subtilis, and Pseudomonas aeruginosa). Amazingly, our bioplastic films have conducted potent antimicrobial activities. So, they may be promising in such a direction. Further, the biodegradability efficacy of bioplastic films formed was proved in numerous environments for several weeks of incubation. However, all bioplastic films decreased in their weights and changed in their colors, while polypropylene, was very constant all the time. The current findings suggest that our biofilms may be promising for many applications, especially in the field of food package protecting the food, and preventing microbial contamination, consequently, it may help in extending the shelf life of products.


Biodegradable Plastics , Castor Oil , Chitosan , Plasticizers , Starch , Chitosan/chemistry , Chitosan/pharmacology , Castor Oil/chemistry , Biodegradable Plastics/chemistry , Biodegradable Plastics/pharmacology , Plasticizers/chemistry , Starch/chemistry , Animals , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Moths/drug effects , Microbial Sensitivity Tests
3.
Biodegradation ; 35(3): 315-327, 2024 Jun.
Article En | MEDLINE | ID: mdl-37987936

In this article, the degradability by Aspergillus niger and Aspergillus clavatus of three bio-based polyurethane (PU) foams is compared to previous degradability studies involving a Pseudomonas sp. bacterium and similar initial materials (Spontón et al. in Int. Biodet. Biodeg. 85:85-94, 2013, https://doi.org/10.1016/j.ibiod.2013.05.019 ). First, three new polyester-polyurethane foams were prepared from mixtures of castor oil (CO), maleated castor oil (MACO), toluene diisocyanate (TDI), and water. Then, their degradation tests were carried out in an aqueous medium, and employing the two mentioned fungi, after their isolation from the environment. From the degradation tests, the following was observed: (a) the insoluble (and slightly collapsed) foams exhibited free hydroxyl, carboxyl, and amine moieties; and (b) the water soluble (and low molar mass) compounds contained amines, carboxylic acids, and glycerol. The most degraded foam contained the highest amount of MACO, and therefore the highest concentration of hydrolytic bonds. A basic biodegradation mechanism was proposed that involves hydrolysis and oxidation reactions.


Aspergillus , Polyesters , Polyurethanes , Polyurethanes/chemistry , Polyurethanes/metabolism , Polyesters/metabolism , Aspergillus niger/metabolism , Castor Oil/chemistry , Water
4.
Rev Bras Parasitol Vet ; 32(3): e004023, 2023.
Article En | MEDLINE | ID: mdl-37466625

In dogs, Rhipicephalus linnaei transmits pathogens such as Ehrlichia canis, Babesia vogeli, and Hepatozoon canis. The veterinary market has synthetic acaricides to ticks control. Esters derived from castor oil are efficient. However, there is little information about their effects on non-target organisms. This work consisted of a clinical (AST, ALT, and ALP) and histological and histochemical analysis (liver and spleen) of female rabbits exposed to these esters and afoxolaner. The rabbits were divided into three groups: control group (CG) received Bandeirante® rabbit feed; the afoxolaner treatment (TG1) received rabbit feed and two doses of afoxolaner; castor oil esters treatment (TG2) received rabbit feed enriched with esters (1.75 g esters/kg). No alterations were observed in the AST, ALT, and ALP enzymes in exposure to esters TG2. Rabbits from TG1 showed changes in AST. The liver of rabbits exposed to afoxolaner underwent histological and histochemical changes, such as steatosis and vacuolation, as well as poor protein labeling. Polysaccharides were intensely observed in the group exposed to esters. The spleen showed no changes in any of the exposure. Esters from castor oil caused fewer liver changes when incorporated into the feed and fed to rabbits than exposure to afoxolaner.


Acaricides , Dog Diseases , Rhipicephalus sanguineus , Rhipicephalus , Female , Rabbits , Animals , Dogs , Castor Oil/chemistry , Castor Oil/pharmacology , Castor Oil/therapeutic use , Acaricides/pharmacology , Spleen , Esters/pharmacology , Esters/therapeutic use , Liver , Dog Diseases/parasitology
5.
Carbohydr Polym ; 302: 120313, 2023 Feb 15.
Article En | MEDLINE | ID: mdl-36604095

In this study, tunicate cellulose nanocrystals (TCNCs) were introduced into castor oil-based waterborne polyurethane (WPU) to prepare bio-based nanocomposites through a simple solution blending method. The effect of TCNCs content on the particle size and stability of the composite dispersions, as well as the thermophysical and mechanical properties of the composite films were studied and discussed. The unique structure and properties of TCNCs, such as high crystallinity, large aspect ratio and high modulus, not only greatly improved the storage stability of WPU, but also showed significant reinforcing/toughening effects and excellent compatibility to WPU. By drip-coating silver nanowires (AgNWs) on the surface of the composite films, the flexible strain sensors were fabricated, which showed excellent sensitivity in monitoring human movement.


Nanocomposites , Nanoparticles , Nanowires , Urochordata , Wearable Electronic Devices , Animals , Humans , Cellulose/chemistry , Polyurethanes/chemistry , Castor Oil/chemistry , Silver , Nanoparticles/chemistry , Nanocomposites/chemistry
6.
J Oleo Sci ; 71(6): 781-793, 2022.
Article En | MEDLINE | ID: mdl-35661063

Castor oil is a vegetable product extracted from Ricinus communis L (castor seed), which is primarily considered an important commercial value for the manufacturing of soaps, lubricants, coatings, etc. It is rich in hydroxylated fatty acids (ricinoleic acid, 89-92%) and is widely used in the cosmetic, pharmaceutical, oleochemical, and agricultural industries. This oil has also been confirmed as a bactericidal, anti-inflammatory, and antiherpetic agents, due to the ricinoleic acid having functional groups, such as -COOH, -OH, and -C=C-. Furthermore, it is converted into various acid derivative compounds with several applications. Therefore, this article reviewed some reaction stages to the preparation of ricinoleic acid from castor oil. Several methods or reaction pathways were employed in the preparation procedure, such as the Twitchell and Colgate-Emery processes, as well as the alkaline catalyzed, transesterification with methyl ricinoleic, and lipase-catalyzed hydrolysis, respectively. Although each of these preparation methods has advantages and disadvantages, the most effective technique was the hydrolysis through the use of the enzyme lipozyme TL IM. Besides being a green method, the conversion rate in the hydrolysis process was 96.2 ± 1.5.


Ricinoleic Acids , Ricinus communis , Castor Oil/chemistry , Esterification , Fatty Acids/metabolism , Ricinoleic Acids/metabolism
7.
J Colloid Interface Sci ; 614: 451-459, 2022 May 15.
Article En | MEDLINE | ID: mdl-35108636

HYPOTHESIS: Acetic acid, a common pollutant present in museums and art galleries, can irreversibly damage works of art. Herein, a sustainable and scalable synthesis of zinc oxide-castor oil polyurethane hybrids (ZnO/COPs), to be used as acetic acid removers in the preventive conservation of Cultural Heritage, is reported. EXPERIMENTS: The adsorption capacities of ZnO/COPs were studied in saturated acetic acid atmosphere, at low acetic acid gas concentration, and inside a wooden crate (naturally emitting acetic acid) representative of those used in the storage deposits of museums and art collections. FINDINGS: Upon exposure, acetic acid interacts with the castor oil polyurethane and diffuses to the surface of ZnO particles where is stably fixed as zinc acetate crystals. Zinc acetate domains form homogeneously on the surface and are distributed evenly within the ZnO/COPs, thanks to weak interactions between the polyurethane matrix and acetic acid that favour the transport of the acid up to reach the zinc oxide surfaces, resulting in a synergistic effect. The ZnO/COPs composites showed significantly enhanced adsorption capacities of acetic acid surpassing those of the activated carbon benchmark, with the advantage of being easily handled and movable, without the health issues and risks associated to the use of non-confined micro/nano-powders.


Castor Oil , Zinc Oxide , Acetic Acid , Adsorption , Castor Oil/chemistry , Polyurethanes/chemistry , Zinc Oxide/chemistry
8.
J Mater Sci Mater Med ; 32(4): 39, 2021 Apr 01.
Article En | MEDLINE | ID: mdl-33792773

Biomaterials used in tissue regeneration processes represent a promising option for the versatility of its physical and chemical characteristics, allowing for assisting or speeding up the repair process stages. This research has characterized a polyurethane produced from castor oil monoacylglyceride (Ricinus communis L) and tested its effect on reconstructing bone defects in rat calvaria, comparing it with commercial castor oil polyurethane. The characterizations of the synthesized polyurethane have been performed by spectroscopy in the infrared region with Fourier transform (FTIR); thermogravimetric analysis (TG/DTG); X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). For the in vivo test, 24 animals have been used, divided into 3 groups: untreated group (UG); control group treated with Poliquil® castor polyurethane (PCP) and another group treated with castor polyurethane from the Federal University of Piauí - UFPI (CPU). Sixteen weeks after surgery, samples of the defects were collected for histological and histomorphometric analysis. FTIR analysis has shown the formation of monoacylglyceride and polyurethane. TG and DTG have indicated thermal stability of around 125 °C. XRD has determined the semi-crystallinity of the material. The polyurethane SEM has shown a smooth morphology with areas of recesses. Histological and histomorphometric analyzes have indicated that neither CPU nor PCP induced a significant inflammatory process, and CPU has shown, statistically, better performance in bone formation. The data obtained shows that CPU can be used in the future for bone reconstruction in the medical field.


Fractures, Bone/surgery , Monoglycerides/chemistry , Polyurethanes/chemistry , Ricinus/chemistry , Animals , Biocompatible Materials/chemistry , Bone Regeneration/drug effects , Bone Substitutes/pharmacology , Bone and Bones/metabolism , Castor Oil/chemistry , Fracture Healing , Inflammation , Male , Materials Testing , Microscopy, Electron, Scanning , Osteogenesis/drug effects , Rats , Spectroscopy, Fourier Transform Infrared , Temperature , X-Ray Diffraction
9.
Carbohydr Polym ; 264: 118060, 2021 Jul 15.
Article En | MEDLINE | ID: mdl-33910724

This study focuses on the production and characterization of electrosprayed cashew gum (CG) microparticles that encapsulate ß-carotene. CG is an inexpensive, non-toxic polysaccharide obtained from Anacardium occidentale trees. Encapsulation of ß-carotene in CG was performed by electrospraying from two emulsion formulations (water : oil ratios 80:20 and 90:10 (v/v)) in which the dispersed phase consisted of ß-carotene dissolved in castor oil, and the continuous phase was a CG aqueous solution. Spherical particles with smooth surface and medium size between 3 and 6 µm were obtained. The particles produced from the 90:10 (v/v) emulsion showed a loading capacity of 0.075 ± 0.006 % and a minor amount of extractable ß-carotene, 10.75 ± 2.42 %. ATR-FTIR confirmed the absence of interaction between the particles' components. CG demonstrated to offer thermoprotection, and photoprotection for short periods of time. These results make CG a viable candidate to encapsulate bioactive compounds via electrospraying for agricultural, food and pharmaceutical applications.


Anacardium/chemistry , Plant Gums/chemistry , Polysaccharides/chemistry , beta Carotene/chemistry , Agriculture/methods , Castor Oil/chemistry , Drug Compounding/methods , Emulsions/chemistry , Food Industry/methods , Particle Size , Spectroscopy, Fourier Transform Infrared/methods , Thermogravimetry/methods , Water/chemistry
10.
ChemMedChem ; 16(14): 2223-2230, 2021 07 20.
Article En | MEDLINE | ID: mdl-33735940

We present the development of surfactant-free, silica-free and fully biobased oil-in-water antimicrobial Pickering emulsions, based on the self-assembly of ß-cyclodextrin and phytoantimicrobial oils (terpinen-4-ol or carvacrol). Undecylenic acid (UA), derived from castor oil, can be used as bio-based drug to treat fungal infection, but is less effective than petroleum-based drugs as azole derivatives. To maximize its antifungal potential, we have incorporated UA in fully biobased Pickering emulsions. These emulsions are effective against fungi, Gram-positive and Gram-negative bacteria. The carvacrol emulsion charged with UA is +390 % and +165 % more potent against methicillin-resistant S. aureus (MRSA), compared to UA and azole-based commercial formulations. Moreover, this emulsion is up to +480 % more efficient that UA ointment against C. albicans. Finally, remarkable eradication of E. coli and MRSA biofilms was obtained with this environmental-friendly emulsion.


Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Cymenes/pharmacology , Undecylenic Acids/pharmacology , beta-Cyclodextrins/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Candida albicans/drug effects , Castor Oil/chemistry , Cymenes/chemical synthesis , Cymenes/chemistry , Dose-Response Relationship, Drug , Emulsions/chemical synthesis , Emulsions/chemistry , Emulsions/pharmacology , Escherichia coli/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Molecular Structure , Structure-Activity Relationship , Undecylenic Acids/chemical synthesis , Undecylenic Acids/chemistry , beta-Cyclodextrins/chemical synthesis , beta-Cyclodextrins/chemistry
11.
Transplant Proc ; 53(4): 1292-1294, 2021 May.
Article En | MEDLINE | ID: mdl-33714607

A 35-year-old male patient with end-stage renal disease due to vesicoureteral reflux preemptively received a renal graft from his father. The patient had a history of allergy to contrast-enhancing media. He received oral tacrolimus (TAC) and mycophenolate mofetil without any problems for 2 days before kidney transplantation. During the induction period of the surgery, his systolic blood pressure (sBP) decreased to 60 mmHg approximately 1 hour after initiating intravenous tacrolimus (TAC-IV) and intravenous piperacillin (PIPC), and the anesthesiologist suspected drug-induced anaphylaxis and stopped administration of the medications. Because TAC had been administered preoperatively without any adverse events, PIPC was suspected as the causative agent of the anaphylaxis. After the patient's hemodynamics returned to baseline, TAC-IV was restarted. However, his sBP rapidly decreased to 40 mmHg and the patient developed wheezing. He was diagnosed with drug-induced anaphylaxis due to castor oil derivatives in the TAC-IV formulation. The patient's sBP was restored with the administration of some vasopressors, and kidney transplantation was then performed without difficulty. Two days after kidney transplantation, oral TAC was administered without anaphylaxis. Clinicians should consider that not only the drug itself but also its additives or metabolites could induce anaphylaxis.


Anaphylaxis/etiology , Castor Oil/adverse effects , Immunosuppressive Agents/chemistry , Kidney Failure, Chronic/surgery , Kidney Transplantation , Tacrolimus/chemistry , Administration, Intravenous , Adult , Blood Pressure , Castor Oil/chemistry , Graft Rejection/prevention & control , Hemodynamics , Humans , Immunosuppressive Agents/therapeutic use , Male , Mycophenolic Acid/therapeutic use , Piperacillin/therapeutic use , Tacrolimus/therapeutic use
12.
Int J Biol Macromol ; 180: 212-221, 2021 Jun 01.
Article En | MEDLINE | ID: mdl-33737178

This work explores the electrospinnability of low-sulfonate Kraft lignin (LSL)/polyvinylpyrrolidone (PVP) solutions in N,N-dimethylformamide (DMF) and the ability of the different micro- and nano-architectures generated to structure castor oil. LSL/PVP solutions were prepared at different concentrations (8-15 wt%) and LSL:PVP ratios (90:10-0:100) and physico-chemically and rheologically characterized. The morphology of electrospun nanostructures mainly depends on the rheological properties of the solution. Electrosprayed nanoparticles or micro-sized particles connected by thin filaments were obtained from solutions with low LSL/PVP concentrations and/or high LSL:PVP ratios, whereas beaded or bead-free nanofibers were produced by increasing concentration and/or decreasing LSL:PVP ratio, due to enhanced extensional viscoelastic properties and non-Newtonian characteristics. Electrospun LSL/PVP nanofibers are able to form oleogels by simply dispersing them into castor oil at concentrations between 10 and 30 wt%. The rheological properties of the oleogels may be tailored by modifying the LSL:PVP ratio and nanofibers content. The potential application of these oleogels as bio-based lubricants was also explored in a tribological cell. Satisfactory friction and wear results are achieved when using oleogels structured by nanofibers mats with enhanced gel-like properties as lubricants. Overall, electrospinning of lignin/PVP solutions can be proposed as a simple and effective method to produce nanofibers for oil structuring.


Castor Oil/chemistry , Lignin/chemistry , Nanofibers/chemistry , Povidone/chemistry , Dimethylformamide/chemistry , Elasticity , Lubricants/chemistry , Molecular Structure , Organic Chemicals/chemistry , Particle Size , Rheology , Solutions , Viscosity
13.
Carbohydr Polym ; 256: 117507, 2021 Mar 15.
Article En | MEDLINE | ID: mdl-33483029

A series of vegetable oil-based waterborne polyurethane composites were prepared through construction of novel semi-interpenetrating polymers network using carboxymethyl chitosan (CA) as the secondary polymer phase. The effects of CA contents on storage stability, and particle size distribution of the composite dispersions and thermal stability, mechanical properties and surface wettability of composite films were investigated and discussed. The results showed that the composite dispersions displayed excellent storage stability and the biomass contents of resulting films were high up to 80 %. A significant increase in crosslinking density and glass transition temperature of the composite films were observed as the CA contents increased, which was attributed to the increasing hard segment of films and strong hydrogen bonding interaction between polyurethanes and CA. This work provided a simple method to tailor the performance of environmentally friendly vegetable oil-based waterborne polyurethane, which could find application in the field of coatings, adhesives, ink and so on.


Castor Oil/chemistry , Chitosan/analogs & derivatives , Polyurethanes/chemistry , Water/chemistry , Chitosan/chemistry , Drug Stability , Humans , Hydrogen Bonding , Materials Testing , Particle Size , Phase Transition , Tensile Strength , Transition Temperature , Wettability
14.
Carbohydr Polym ; 251: 117060, 2021 Jan 01.
Article En | MEDLINE | ID: mdl-33142612

Due to the poor controlled release ability, bio-based materials are difficult for large scale application on controlled release fertilizers (CRFs). Starch-based polyol (SP) and castor oil (CO) were mutually modified, and a cross-linked polymer film was formed on the surface of urea by in-situ reaction, which improved the slow release ability of the bio-based material. The results showed that increasing the CO ratio reduced porosity of coating and prolonged the nitrogen (N) release period, while the SP changed the high-temperature wrinkle characteristics and regulated the early N release rate. The mutual modification achieved an ultra-long release period of bio-based CRUs for 7 months. The degradation rate during nine months of bio-based coatings (5.05 %) was significantly higher than that of petroleum-based (3.74 %), and the coating was non-toxic to rice seeds. Mutual modification provided a safe and effective solution for the preparation of bio-based CRFs with long-term controlled release capability.


Castor Oil/chemistry , Cross-Linking Reagents/chemistry , Delayed-Action Preparations/chemistry , Fertilizers/analysis , Polyurethanes/chemistry , Starch/chemistry , Urea/metabolism , Delayed-Action Preparations/pharmacology , Oryza/chemistry , Polymers/chemistry , Urea/chemistry
15.
Protoplasma ; 258(2): 391-401, 2021 Mar.
Article En | MEDLINE | ID: mdl-33130947

Castor, a non-food, dedicated bioenergy crop, has immense potential to be used for phytoremediation/revegetation of heavy metal contaminated sites. In the previous study, we identified arsenate [As(V)]-tolerant (WM) and As(V)-sensitive (GCH 2) genotypes of castor (Ricinus communis L.) with differential accumulation and tolerance of arsenic [As]. The role of thiols in As(V) toxicity and tolerance mechanism in the castor plant is not fully understood. On the one hand, thiol-dependent reduction of As(V) to As(III) by arsenate reductase (AR) makes it capable of reacting with thiol groups of protein leading to disturbed metabolic pathways; on the other hand, reduction of As(V) to arsenite [As(III)] by AR and then complexation of As(III) with phytochelatins (PCs) and compartmentalization of As(III)-PC complex are considered as the major detoxification mechanisms of As(V). In our study, the expression of RcAR increased in leaves and roots of As(V)-tolerant castor genotype WM but decreased in sensitive genotype GCH 2 due to 200 µM As(V) treatment. The activity of glutathione reductase (GR) increased significantly in the tolerant genotype, whereas it remained same in the sensitive genotype. GSH/GSSH ratio declined substantially in the sensitive genotype. The increased expression of phytochelatin synthase 1 isoform 1 (RcPCS1X1) in roots, RcPCS1X2 and metallothionein type 2 (RcMT2) in leaves, and c-type ABC transporter (RcABCC) in roots and leaves of WM was observed, but the expression of these genes declined or remained the same in GCH 2. Overall, our results suggest the essential roles of GR, RcAR, RcPCS1, RcMT2, and RcABCC in the tolerance of WM castor genotype to As(V) toxicity.


Arsenates/metabolism , Arsenic/blood , Castor Oil/chemistry , Ricinus/chemistry , Sulfhydryl Compounds/metabolism , Genotype
16.
Int J Nanomedicine ; 15: 5405-5416, 2020.
Article En | MEDLINE | ID: mdl-32801696

PURPOSE: Although the effective and safe medical defoamers, dimethicone (DM) and simethicone (SM) are widely used in electronic gastroscope examination (EGE), their preparations are presented in the form of suspensions or emulsions, these are untransparent or milk-like in appearance and can easily cause misdiagnosis as a result of an unclear field of vision if the doctor does not master the amount of defoamer or operates incorrectly. At the same time, it is also difficult to wash out the camera and pipeline, due to the large oil droplets of preparations. The purpose of this study was to develop a new clear and transparent oil in water (O/W) DM nanoemulsions (DMNs) and observe the effect of application in EGE. METHODS: The oil phase was chosen for its antifoaming activity and viscosity. The emulsifier and co-emulsifier were selected according to the solubility of the oil phase in them. The water titration method was used to make the pseudoternary phase diagrams of nanoemulsions and optimize the prescription composition. DM-in-water nanoemulsion was prepared by the low energy method and evaluated for appearance, antifoaming ability, droplet size, and stability. The effect of DMNs utilized in EGEs was also observed. RESULTS: The optimal formulation of DMNs contained CRH-40 as an emulsifier, PEG-400 as a co-emulsifier, DM as oil phase with the viscosity of 10 mPa.s, and their proportion was 4.5:4.5:1, respectively. DMNs obtained the average particle size of 67.98 nm with the polydispersity index (PDI) of 0.332, and 57.14% defoaming rate. The result of using an EGE showed that DMNs were superior in comparison to the emulsions with regard to the defoaming effect, visual clarity, and easy cleanup. CONCLUSION: DMNs were found to provide excellent visual clarity to its other preparations. The novel DMNs is a promising substitute for DM emulsions or suspensions in EGEs.


Antifoaming Agents/chemistry , Dimethylpolysiloxanes/chemistry , Emulsions/chemistry , Gastroscopy/methods , Antifoaming Agents/adverse effects , Antifoaming Agents/therapeutic use , Castor Oil/chemistry , Dimethylpolysiloxanes/adverse effects , Dimethylpolysiloxanes/therapeutic use , Emulsifying Agents/chemistry , Female , Gastroscopy/adverse effects , Humans , Male , Nanostructures/chemistry , Particle Size , Polyethylene Glycols/chemistry , Solubility , Viscosity
17.
ACS Appl Mater Interfaces ; 12(33): 37607-37618, 2020 Aug 19.
Article En | MEDLINE | ID: mdl-32814393

The deposition of pesticides and their retention on plant surfaces are critical challenges for modern precision agriculture, which directly affect phytosanitary treatment, bioavailability, efficacy, and the loss of pesticides. Herein, a novel and eco-friendly waterborne polyurethane delivery system was developed to enhance the spray deposition and pesticide retention on plant surfaces. More specifically, biobased cationic and anionic waterborne polyurethane dispersions were synthesized from castor oil. Both cationic and anionic polyurethane dispersions exhibited remarkable microstructural, amphiphilic, and nanoparticle morphologies with a core-shell structure that served to encapsulate a biopesticide (azadirachtin) in their hydrophobic cores (WPU-ACT). The results indicated that the cationic WPU-ACT carriers exhibited a better sustained release behavior and a better protective effect from light and heat for azadirachtin. In addition, the simultaneous spray of anionic and cationic WPU-ACT significantly enhanced the spray deposition and prolonged the retention of pesticides due to the reduced surface tension and surface precipitation induced by the electrostatic interaction when two droplets with opposite charges come into contact with each other. A field efficacy assessment also indicated that the simultaneous spray of anionic and cationic WPU-ACT could control the infestation of brown planthopper in rice crops. Castor oil-based waterborne polyurethanes in this study work as an efficient pesticide delivery system by exhibiting enhanced deposition, rainfastness, retention ability, protection, and sustained release behavior, holding great promise for spraying pesticide formulations in modern and environmentally friendly agricultural applications.


Castor Oil/chemistry , Delayed-Action Preparations/chemistry , Drug Carriers/chemistry , Limonins/chemistry , Pesticides/chemistry , Polyurethanes/chemistry , Agriculture , Drug Compounding , Drug Liberation , Green Chemistry Technology , Hydrophobic and Hydrophilic Interactions , Limonins/pharmacology , Pesticides/pharmacology , Static Electricity , Surface Properties , Water
18.
Molecules ; 25(12)2020 Jun 25.
Article En | MEDLINE | ID: mdl-32630602

The present paper investigates the feasibility of using acetone (ACE) in triple blends with fossil diesel (D) and straight vegetable oils (SVOs) as alternative fuel for diesel engines. In this respect, ACE is selected as an oxygenated additivedue to its favorable propertiesto be mixed with vegetable oils and fossil diesel. In fact, the very low kinematic viscosity allows reduces the high viscosity of SVOs. ACE's oxygen content, low autoignition temperature, and very low cloud point and pour point values highlight its possibilities as an additive in D/ACE/SVO triple blends. Moreover, ACE can be produced through a renewable biotechnological process, an acetone-butanol-ethanol (ABE) fermentation from cellulosic biomass. The SVOs tested were castor oil (CO), which is not suitable for human consumption, and sunflower oil (SO), used as a standard reference for waste cooking oil. The viscosity measurement of the ACE/SVO double blend was considered crucial to choose the optimum proportion, which better fulfilled the specifications established by European standard EN 590. Moreover, some of the most significant physicochemical properties of D/ACE/SVO triple blends, such as kinematic viscosity, cloud point, pour point, and calorific value, were determined to assess their suitability as fuels. The blends were evaluated in a conventional diesel generator through the study of the following parameters: engine power, smoke emissions, and fuel consumption. Despite the low calorific value of ACE limits its ratio in the mixtures due to engine knocking problems, the experimental results reveal an excellent performance for the blends containing up to 16-18% of ACE and 22-24% of SVO. These blends produce similar engine power as to fossil diesel, but with slightly higher fuel consumption. Considerable reductions in emissions of air pollutants, as well as excellent cold flow properties are also obtained with these triple blends. In summary, the use of these biofuels could achieve a substitution of fossil diesel up to 40%, independently on the SVO employed.


Acetone/chemistry , Biofuels/analysis , Castor Oil/chemistry , Gasoline/analysis , Plant Oils/chemistry , Sunflower Oil/chemistry , Vehicle Emissions/analysis , Humans
19.
Int J Biol Macromol ; 163: 878-887, 2020 Nov 15.
Article En | MEDLINE | ID: mdl-32653368

Cellulose nanocrystals (CNCs), castor oil (CO), and recycled poly(ethylene terephthalate) (rPET), were used to add value to renewable raw materials and to a recycled polymer produced worldwide, producing mats composed of fibers on the nano- and submicrometric (ultrathin) scales through a sustainable process. Bio-based electrospun mats composed of aligned (rotary collector) and nonaligned (static collector) nanofibers/ultrathin fibers were produced from the electrospinning of solutions prepared from rPET (mixed with CO, CNCs, or CNCs/CO). The contact angle results showed that the CNC mat surfaces composed of nonaligned fibers were hydrophilic, and in contrast, these surfaces were hydrophobic when composed of aligned fibers. Among the mats composed of nonaligned fibers, PET/CO/CNC exhibited storage and Young's moduli approximately eleven and ten times, respectively, better than those of neat rPET. The PET/CO/CNC mat showed both modulus and tensile strength values higher than those of PET/CNC, when characterized in the preferential direction of fiber alignment. Electrospun mats were obtained from environmentally sound raw materials with diversified properties, which were modulated by the type of collector used, as well as whether CO and CNC were mixed with rPET, and have the potential for use in applications such as membrane separation processes and biomedical applications.


Castor Oil/chemistry , Cellulose/chemistry , Nanofibers/chemistry , Nanoparticles/chemistry , Polyethylene Terephthalates/chemistry , Chemical Phenomena , Mechanical Phenomena , Nanocomposites , Nanofibers/ultrastructure , Nanoparticles/ultrastructure , Tensile Strength
20.
Int J Nanomedicine ; 15: 2935-2945, 2020.
Article En | MEDLINE | ID: mdl-32425525

BACKGROUND: New anticancer agents that rely on natural/healthy, not synthetic/toxic, components are very much needed. METHODS: Ricinoleyl hydroxamic acid (RHA) was synthesized from castor oil and hydroxylamine using Lipozyme TL IM as a catalyst. To optimize the conversion, the effects of the following parameters were investigated: type of organic solvent, period of reaction, amount of enzyme, the molar ratio of reactants and temperature. The highest conversion was obtained when the reaction was carried out under the following conditions: hexane as a solvent; reaction period of 48 hours; 120 mg of Lipozyme TL IM/3 mmol oil; HA-oil ratio of 19 mmol HA/3 mmol oil; and temperature of 40°C. The cytotoxicity of the synthesized RHA was assessed using human dermal fibroblasts (HDF), and its application towards fighting cancer was assessed using melanoma and glioblastoma cancer cells over a duration of 24 and 48 hours. RESULTS: RHA was successfully synthesized  and it demonstrated strong anticancer activity against glioblastoma and melanoma cells at as low as a 1 µg/mL concentration while it did not demonstrate any toxicity against HDF cells. CONCLUSION: This is the first report on the synthesis of RHA with great potential to be used as a new anticancer agent.


Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Castor Oil/chemistry , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Catalysis , Cell Line, Tumor , Cell Survival/drug effects , Fibroblasts/drug effects , Glioblastoma/drug therapy , Glioblastoma/pathology , Hexanes/chemistry , Humans , Hydroxylamine/chemistry , Lipase/chemistry , Lipase/metabolism , Melanoma/drug therapy , Melanoma/pathology , Solvents/chemistry
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