scholarly journals Release kinetics of lime essential oil (Citrus aurantifolia) from beads microencapsulated through ion-gel method

2021 ◽  
Vol 20 (1) ◽  
pp. 58-66
Author(s):  
Vinh Truong

Ca-Alginate beads for microencapsulation of lime oil (Citrus aurantifolia) by ion-gel method was manufactured and then soaked in Chitosan solution to obtain Ca-Alginate-Chitosan beads. Increased CaCl2 concentrations reduced lime essential oil release. The alginate concentration (2 to 3%) and water temperature significantly affected the release of oil (P < 0.05). The higher temperatures, the higher the release rate. The oil release at 75oC was twice as much as at 45oC. At 45oC, the difference in the release rate among the alginate concentrations of 2%, 2.5% and 3% was clear and statistically significant (P < 0.05). However, at 60oC and 75oC, there was no significant difference in release between the alginate concentration of 2.5% and 3% (P > 0.05). In the storage of beads in 1% CaCl2 solution at normal temperature, after the first 15 days, Ca Alginate-Chitosan system released about 3% slower than Ca-Alginate system, but there was no difference between the two systems after 45 days. This shows that if prolonged for a long time, the ion-gelation of Ca-Alginate prevails over the Alginate-Chitosan cross-link.

2020 ◽  
Vol 19 (01) ◽  
pp. 65-76
Author(s):  
Vinh Truong

The extrusion-dripping method to produce alginate-calcium beads for microencapsulation of lime oil (Citrus aurantifolia) was carried out in this study. The experimental range of alginate concentration was from 1 to 4%. Above 1% alginate concentration, viscosity was pseudoplastic behavior. The size (1.52 - 1.57 mm) and sphericity (above 95%) of the beads were maximum at alginate concentration of 2 - 3%. The extrusion-dripping method was not applicable when alginate concentration was over 3.5% due to the high viscosity resulting in low sphericity. The two types of alginates with a protein content of 9% (alg1) and 2% (alg2) had the same microencapsulation yield of 73 - 74%. However, the solid recovery of alg2 (98.99%) was much higher than that of alg1 (52.71%). This is because alg2 has a higher purity and if it is used in production, it is easier to control the content of active ingredients and reduce the amount of organic waste that is harmful to the environment compared to alg1.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Kamal Essifi ◽  
Mohamed Brahmi ◽  
Doha Berraaouan ◽  
Abderrahim Ed-Daoui ◽  
Ali El Bachiri ◽  
...  

To understand the abilities of Ca-alginate microcapsules and their specific applications in different fields, it is necessary to determine the physicochemical and structural properties of those formulated microcapsules. In this work, we aimed to study the effect of alginate concentration in the improvement of the encapsulation efficiency (EE) and on the release of phenolic and flavonoid substances. The relationship between the structure of the encapsulated bioactive substance and Ca-alginate network and their effect on the EE and release kinetics have been investigated. The incorporation, structure, morphology, and phase properties of all elaborated materials were characterized by UV-spectroscopy, Fourier transform infrared (ATR-FTIR), scanning electron microscope (SEM), and X-ray diffraction (DRX). The results indicate that increasing the polymer concentration increases the EE and decreases the loading capacity (LC), whereas the effect of alginate polymer concentration on the release was not observed. The release study of bioactive substances showed that the release kinetics is relatively dependent on the structure and the physicochemical characteristics of the bioactive substance, which became clear when the encapsulated compounds were released from the core of calcium alginate microcapsules. Thus, it could be concluded that the pores size of the Ca-alginate network is smaller than the volume of the crocin molecule (2794.926 Å3) and higher than the volume of the gallic acid molecule (527.659 Å3). For the same microcapsules system, the release mechanism is affected by the structure and physicochemical properties of the encapsulated molecules.


2020 ◽  
pp. 15-27

In order to study the effect of phosphogypsum and humic acids in the kinetic release of salt from salt-affected soil, a laboratory experiment was conducted in which columns made from solid polyethylene were 60.0 cm high and 7.1 cm in diameter. The columns were filled with soil so that the depth of the soil was 30 cm inside the column, the experiment included two factors, the first factor was phosphogypsum and was added at levels 0, 5, 10 and 15 tons ha-1 and the second-factor humic acids were added at levels 0, 50, 100 and 150 kg ha-1 by mixing them with the first 5 cm of column soil and one repeater per treatment. The continuous leaching method was used by using an electrolytic well water 2.72 dS m-1. Collect the leachate daily and continue the leaching process until the arrival of the electrical conductivity of the filtration of leaching up to 3-5 dS m-1. The electrical conductivity and the concentration of positive dissolved ions (Ca, Mg, Na) were estimated in leachate and the sodium adsorption ratio (SAR) was calculated. The results showed that the best equation for describing release kinetics of the salts and sodium adsorption ratio in soil over time is the diffusion equation. Increasing the level of addition of phosphogypsum and humic acids increased the constant release velocity (K) of salts and the sodium adsorption ratio. The interaction between phosphogypsum and humic acids was also affected by the constant release velocity of salts and the sodium adsorption ratio. The constant release velocity (K) of the salts and the sodium adsorption ratio at any level of addition of phosphogypsum increased with the addition of humic acids. The highest salts release rate was 216.57 in PG3HA3, while the lowest rate was 149.48 in PG0HA0. The highest release rate of sodium adsorption ratio was 206.09 in PG3HA3, while the lowest rate was 117.23 in PG0HA0.


2014 ◽  
Vol 48 (3) ◽  
pp. 492-499 ◽  
Author(s):  
Juliana Rizzo Gnatta ◽  
Patricia Petrone Piason ◽  
Cristiane de Lion Botero Couto Lopes ◽  
Noemi Marisa Brunet Rogenski ◽  
Maria Júlia Paes da Silva

Objective: To verify if the use of ylang ylang essential oil by cutaneous application or inhalation alters the anxiety and self-esteem perception and physiological parameters as blood pressure and temperature. Method : A pilot study with 34 professionals from a nursing group randomized in three groups: one received the ylang ylang essential oil by cutaneous application, the second received through inhalation and the third (placebo) received the ylang ylang essence through cutaneous application. The assessment was done by an Anxiety Inventory (IDATE) and the Dela Coleta self-esteem scale, applied on baseline, after 30, 60 and 90 days and after 15 days post-intervention (follow up). Results : In the pre and post-intervention intergroup analysis, there was a significant difference in self-esteem for the three groups (p values: G1=0.014; G2=0.016; G3=0.038). There were no differences in the analysis between groups for anxiety or for physiological parameters. Conclusion : It was found significant alterations only to the intergroup perception of self-esteem for the three groups.



2018 ◽  
Vol 66 (4) ◽  
pp. 1519
Author(s):  
Mailen Ortega Cuadros ◽  
Adriana Patricia Tofiño Rivera ◽  
Luciano Jose Merini ◽  
Maria Cecilia Martinez Pabon

Dental caries is a pathology of multifactorial origin and currently natural products are an efficient alternative treatment; The work sought to evaluate the antimicrobial activity of the Cymbopogon citratus essential oil and the citral and myrcene components against Streptococcus mutans ATCC UA159, as well as their cytotoxicity on keratinocytes and human fibroblasts. The viability effect against Streptococcus mutans on biofilms was evaluated through exposure to the three substances by using the MBEC technique-high-throughput at concentrations of 1, 0.1, and 0.01 µg/mL and chlorhexidine as positive control. The cytotoxicity of the compounds was evaluated on keratinocytes and fibroblasts through the MTT reduction technique, using 0.5 mM H2O2 as cell-death control (negative control) and ethanol 1% as vehicle control (positive control). The three substances evaluated had effects on the viability of Streptococcus mutans with mortality between 74% and 96%, without significant difference among them (p > 0.393); additionally, no cytotoxicity was evident on keratinocytes and fibroblasts in a 24-h treatment. The substances evaluated showed significant antimicrobial effects; hence, these should be studied further as potential co-adjuvants to prevent dental caries that cause minor adverse effects


Author(s):  
Antonín Vaculík

Caraway has very low competitive ability against most of weed species. Therefore, it is important to choose a suitable herbicide control, especially at biennial caraway. The experiments with the herbicides applied in caraway were found in pure growth, with variety Kepron (with standard length of ve­ge­ta­ti­ve period). The aim of the trials was to find out the differences at achenes yiled and essential oil content after the treatment by the various herbicides, applied preemergently. Also, the selective ac­ti­vi­ty of individual herbicides was tested, including the different doses. The herbicides used in the ex­pe­ri­ments had enough level of selektivity on the plants of caraway. They had a positive effect on the yiled comparing to non-treated control variant in all observed years. There was no statistically significant difference in essential oil kontent between the treated variants and non-treated control. On the basis of these results, the most suitable herbicide was chosen for the „minor“ registration for caraway.


2020 ◽  
Author(s):  
Desmond Onyeka Agwunobi ◽  
Tingwei Pei ◽  
Xiaoshuang Wang ◽  
Zhijun Yu ◽  
Jing-Ze Liu

Abstract Background: The tick Haemaphysalis longicornis is well known as vector of several zoonotic pathogens responsible for various clinical conditions, increasingly threatens the veterinary and public health. It is mainly distributed in East Asia, New Zealand, Australia, and several Pacific islands, and has been expanded rapidly in United States since its first founding on a nonimported domestic sheep in New Jersey. Glutathione S-transferases (GSTs) are phase II detoxification enzymes, which function via combining with pesticidal molecules and catalyzing the conjugation of molecules by thiol of glutathione, so as to protect tissues from oxidative stress damage. In the tick H. longicornis, glutathione S-transferases (HlGST and HlGST2) have been previously identified. However, the relationship between the expression of glutathione S-transferases and the essential oil treatment in ticks remains unexplored. Hence, in the present study, the expression profiles of HlGST and HlGST2 mRNAs were evaluated in H. longicornis after exposure to Cymbopogon citratus essential oil. Results: At 24 h post-exposure of H. longicornis to different sublethal concentrations of C. citratus essential oil, ANOVA results revealed significant difference (F2,6 = 55.94, P = 0.0001) in the expression of HlGST. Tukey’s test showed that HlGST was significantly induced after treatment with 1% C. citratus essential oil (P = 0.0002); whereas no significant difference (P = 0.3551) was detected after treated by 2% C. citratus essential oil. No significant difference (F2,6 = 0.8990, P = 0.4555) in the expression of HlGST2 between the treatment and the control group of 50% ethanol. Nevertheless, the under-expression of HlGST2 in the treatment groups versus the untreated control group was not significant (F3,8 = 2.643, P = 0.1208). Conclusion: The results implied that GST mRNA is a potential molecular target for C. citratus essential oil in H. longicornis. Further understanding of the underlying mechanisms of the GST at the molecular level could contribute to develop effective control measures for ticks and tick-borne diseases.


2008 ◽  
Vol 3 (7) ◽  
pp. 1934578X0800300 ◽  
Author(s):  
Anthony J. Afolayan ◽  
Olayinka T. Asekun

Most often during the processing of lime fruits for essential oil extraction, rotten fruits are used along with ripe ones. In this study, we examine the volatile constituents of the essential oils from both ripe and rotten lime fruits (Citrus aurantifolia Swingle) from Nigeria. The oils were isolated by hydrodistillation and analyzed using GC-MS. The ripe and rotten lime oils contained 55 and 49 components, respectively. Both oils were rich in limonene (21.0%, ripe lime; 21.3% rotten lime), α-terpineol (11.7%, ripe; 14.1%, rotten), terpinene (8.3%, ripe; 8.9% rotten lime), α–terpinolene (2.5%, ripe; 8.5%, rotten) and ( E)-α-farnesene (6.3% ripe lime; 4.8% rotten lime). The other major components, α-pinene (11.1%), and linalool (5.5%) were identified in ripe lime oil only. Limonene and citral, which are believed to be the two major citrus odour contributors, were present in both ripe and rotten lime oils. Aldehydes like decanal and the farnesenes, which are also important in citrus flavor, were represented in both lime oils. Some notable components of ripe lime fruit oil, like trans-β-ocimene, linalool, myrcenol, dodecanal, trans-β–bergamotene and trans-γ–bisabolene, were absent in the rotten fruit oil. It could be suggested that some compounds like cis-ocimene, trans-linalool oxide, p-mentha-3-en-1-ol, mentha-1,4,8-triene, citronellal, trans- β–bergamotene and α–copaene, which were not identified in the ripe fruit oil, were introduced into the lime oil by the incorporation of rotten fruits in the distilled samples.


Sign in / Sign up

Export Citation Format

Share Document