Anisotropy and nonlinear properties of electrochemical circuits in leaves of Aloe vera L

Plant tissue has biologically closed electrical circuits and electric fields that regulate its physiology. The biologically closed electrochemical circuits in the leaves of Aloe vera were analyzed using the charge stimulation method with Ag/AgCl electrodes inserted along a leaf at 1-2 cm distance. The electrostimulation was provided with different timing and different voltages. Strong electrical anisotropy of the leaves was found. In the direction across the leaf the electrical circuits remained passive and linear, while along the leaf the response remained linear only at small voltages not exceeding 1 V. At higher potentials the circuits became strongly non-linear pointing to the opening of voltage gated ion channels in the plant tissues. Changing the polarity of electrodes located along conductive bundles led to a strong rectification effect and to different kinetics of capacitor discharge. Equivalent electrical circuit models of the leaf were proposed to explain the experimental data.     

Antibacterial cotton fabric with in situ generated silver nanoparticles by one-step hydrothermal method

The cotton fabrics were immersed in 1–5?mM aqueous silver nitrate solutions maintained at 80°C for 24?h to in situ generate silver nanoparticles. The presence of silver nanoparticles in the nanocomposite films was proved by microscopic observation. Fourier transform infrared spectra indicated the role of hydroxyl and carboxyl groups of cotton fabric in reducing the silver salt to nanosilver. The nanocomposite cotton fabrics showed good antibacterial activity against Gram-negative and Gram-positive bacteria. The antibacterial cotton fabrics can be considered for medical applications such as surgical aprons, wound cleaning, and dressing.     

Composition and applications of Aloe vera leaf gel

Many of the health benefits associated with Aloe vera have been attributed to the polysaccharides contained in the gel of the leaves. These biological activities include promotion of wound healing, antifungal activity, hypoglycemic or antidiabetic effects antiinflammatory, anticancer, immunomodulatory and gastroprotective properties. While the known biological activities of A. vera will be briefly discussed, it is the aim of this review to further highlight recently discovered effects and applications of the leaf gel. These effects include the potential of whole leaf or inner fillet gel liquid preparations of A. vera to enhance the intestinal absorption and bioavailability of co-administered compounds as well as enhancement of skin permeation. In addition, important pharmaceutical applications such as the use of the dried A. vera gel powder as an excipient in sustained release pharmaceutical dosage forms will be outlined.     

Gamma irradiation improves the antioxidant activity of Aloe vera (Aloe barbadensis miller) extracts

Aloe has been widely used in food products, pharmaceuticals, and cosmetics because of its aromatic and therapeutic properties. In the present study, the ethanolic extracts of aloe gel were gamma-irradiated from 10 to 100 kGy. After gamma irradiation, the color of the ethanolic extracts of aloe gel changed to red; this color persisted up to 40 kGy but disappeared above 50 kGy. Liquid chromatography/mass spectrometry analysis demonstrated the production of a new, unknown compound (m/z=132) after gamma irradiation of the ethanolic extracts of aloe gel. The amount of this unknown compound increased with increasing irradiation up to 80 kGy, and it was degraded at 100 kGy. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by the 1,1-diphenyl-2-picrylhydrazyl-radical scavenging capacity. The antioxidant activity of aloe extract was dramatically increased from 53.9% in the non-irradiated sample to 92.8% in the sample irradiated at 40 kGy. This strong antioxidant activity was retained even at 100 kGy. These results indicate that gamma irradiation of aloe extract can enhance its antioxidant activity through the formation of a new compound. Based on these results, increased antioxidant activity of aloe extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.     

Determination of three compounds in Aloe vera by capillary electrophoresis

A capillary electrophoretic assay for determining aloe-emodin (AE), methyl p-coumarate (MC), and 3,4-dihydro-6,8-dihydroxyl-[(3s)-2'-acetyl-3'-hydroxyl-5'-methoxy-benzyl]-isocoumarin (DDI) in Aloe vera has been developed. Baseline separation was achieved within 15 min using a running buffer of 20 mm borax containing 10% (v/v) acetonitrile at pH 10.5. A linear relationship between the peak area and the concentration of the analytes was found in the ranges 5-500, 10-1000 and 2-1000 micro g/mL for AE, MC and DDI, respectively, with correlation coefficients of 0.9992-0.9998. The relative standard deviations of migration time and peak area were within 0.17-0.19 and 1.52-3.37%, respectively. The recoveries of AE, MC and DDI were 105, 102 and 96.4%. The contents of AE, MC and DDI in Aloe vera were measured to be 5.13, 0.768 and 1.30 mg/g, respectively.     

Synthesis of nickel oxide nanorods by Aloe vera leaf extract

Journal of Thermal Analysis and Calorimetry - Nickel oxide nanorods were synthesized simply using Aloe vera extract solution and characterized by Fourier transform infrared spectroscopy and powder...     

Electrical signaling in Aloe vera induced by localized thermal stress

Action potentials in higher plants are theorized as the information carriers in intercellular and intracellular communication in the presence of environmental stressors. Among the most common stressors is heat shock. Under stressful conditions, the response reactions of plant tissues and organs can be local or transmitted over long distances. In this article, the speeds of propagation of thermally induced action potentials in green plants are discussed, and their speeds were found to be comparable to those occurring in various mammalian species. These rapid action potentials in green plants were recorded in real time using modern data acquisition techniques. According to our measurements, a single application of localized heat stress induces fast action potentials in Aloe vera (67 m/s). Electrical signals propagated along all leaves of the A. vera plants were studied. Possible pathways for electrical signal propagation in vascular plants are also discussed.     

Thermal properties of cotton fabric modified with poly (propylene imine) dendrimers

For the first time, thermal stability and flame retardant properties of cotton fabrics modified with poly (propylene imine) dendrimer (PPI-dendrimer) using cross linking agents have been reported. The PPI-dendrimers can be considered as novel nitrogen flame retardant agents, because they contain a large number of nitrogen-containing groups (amine end groups), which may release nitrogen gas or ammonia. In this paper, the effect of the PPI-dendrimers on thermal behavior of cotton fabric is investigated through thermogravimetric analysis, differential scanning calorimetry, flammability (in vertical configuration) and limiting oxygen index tests. Indeed, both thermal stability and flame retarancy of the modified fabrics have significantly enhanced. Furthermore, field emission scanning electron microscopy micrographs have been studied in order to evaluate morphology of the cotton samples. Crystallinity and physical properties including crease recovery angle, breaking strength, whiteness index and hygroscopicity of the samples have been also assessed.     

Bio-derived efficient flame-retardants for cotton fabric

Cellulose - This paper presents a facile synthesis method for bio-derived (from the bark of Terminalia arjuna and tea powder) phosphorus-functionalized materials (AB-P and TP-P). The resulting...     

Development of antimicrobial cotton fabric using bionanocomposites

In order to provide antimicrobial activity to cotton, cotton fabrics were treated by montmorillonite (KSF), montmorillonite–dihydroxy ethylene urea (KSF–MDEU), KSF–chitosan (CS) and KSF–CS–MDEU solutions containing 12.5, 25 and 50 ppm silver ion. The effect of modification on the antibacterial activity of cotton fabrics was also evaluated after 10 cycles of washings. MDEU exhibited better antimicrobial activities after washing process. By using 25 ppm silver, KSF and CS modification solution, good performance in terms of antibacterial activity was obtained. The addition of CS and MDEU increased the whiteness index values of cotton fabrics treated with KSF containing different silver concentrations. The characterization of modified cotton samples was done by Fourier transform infrared spectroscopy, X-ray diffraction analysis, inductively coupled plasma-mass spectroscopy, scanning electron microscopy and thermogravimetric analysis.     

Standardization of Ayurvedic Formulations Containing Aloe vera by Quantification of a Marker Compound

JPC – Journal of Planar Chromatography – Modern TLC - HPTLC has been used for quantitative analysis of aloin, as marker compound, in commercial Ayurvedic preparations, in the solid...     

Self-extinguishing cotton fabric with minimal phosphorus deposition

The phosphorus-containing acrylate monomer, 2-acryloyloxyethyl diethyl phosphate (ADEP), was synthesized and applied to cotton fabric by using the admicellar polymerization technique. A cationic surfactant (cetylpyridinium chloride, CPC) was used as the surfactant for admicellar polymerization. Results from FTIR-ATR and SEM showed that PADEP polymer film was successfully formed on the cotton fabric surface. TGA and DTG analyses showed that the phosphorus-containing PADEP lowered the decomposition temperature of the treated fabric resulting in a higher char yield than in the case of untreated cotton. The flammability tests showed that PADEP-coated cotton with the phosphorus content 4.18 mg/g cotton was self-extinguishing, with the flame extinguishing right after the removal of the ignition source leaving a small area of char formation.     

Circadian variations in biologically closed electrochemical circuits in Aloe vera and Mimosa pudica

The circadian clock regulates a wide range of electrophysiological and developmental processes in plants. This paper presents, for the first time, the direct influence of a circadian clock on biologically closed electrochemical circuits in vivo. Here we show circadian variation of the plant responses to electrical stimulation. The biologically closed electrochemical circuits in the leaves of Aloe vera and Mimosa pudica, which regulate their physiology, were analyzed using the charge stimulation method. The electrostimulation was provided with different timing and different voltages. Resistance between Ag/AgCl electrodes in the leaf of Aloe vera was higher during the day than at night. Discharge of the capacitor in Aloe vera at night was faster than during the day. Discharge of the capacitor in a pulvinus of Mimosa pudica was faster during the day. The biologically closed electrical circuits with voltage gated ion channels in Mimosa pudica are also activated the next day, even in the darkness. These results show that the circadian clock can be maintained endogenously and has electrochemical oscillators, which can activate ion channels in biologically closed electrochemical circuits. We present the equivalent electrical circuits in both plants and their circadian variation to explain the experimental data.     

Novel Bio-Functional Aloe vera Beverages Fermented by Probiotic Enterococcus faecium and Lactobacillus lactis

Aloe vera has been medicinally used for centuries. Its bioactive compounds have been shown to be very effective in the treatment of numerous diseases. In this work, a novel functional beverage was developed and characterized to combine the health benefits of probiotic bacteria with the Aloe vera plant itself. Two Aloe vera juices were obtained by fermentation either by a novel isolated Enterococcus faecium or a commercial Lactococcus lactis. The extraction of Aloe vera biocompounds for further fermentation was optimized. Extraction with water plus cellulase enhanced the carbohydrates and phenolic compounds in the obtained extracts. The biotransformation of the bioactive compounds from the extracts during fermentation was assessed. Both probiotic bacteria were able to grow on the Aloe vera extract. Lactic acid and short-chain fatty acids (SCFA) together with fourteen individual phenolic compounds were quantified in the produced Aloe vera juice, mainly epicatechin, aloin, ellagic acid, and hesperidin. The amount of total phenolic compounds was maintained through fermentation. The antioxidant activity was significantly increased in the produced juice by the ABTS method. The novel produced Aloe vera juice showed great potential as a functional beverage containing probiotics, prebiotics, SCFA, and phenolic compounds in its final composition.     

Chemical cationization of cotton fabric for improved dye uptake

Cotton fabric is usually dyed with reactive dyes. During the dyeing process, a large amount of salt is required to achieve higher exhaustion of the dye from the dyebath onto the fiber. Dyeing of cotton with reactive dyes has a substantial environmental impact due to the discharge of a large volume of highly colored and saline effluents. Chemical cationization allows cotton fibers to be dyed without salt by chemically modifying cellulosic macromolecules to introduce positively charged sites. In this study, cotton fabric was cationized using (3-chloro-2-hydroxylpropyl) trimethyl-ammonium chloride (CHPTAC). Dye uptake was assessed using two reactive dyes, CI Reactive Blue 235 and CI Reactive Blue 19. Dye exhaustion kinetics were determined using a Datacolor-HueMetrix Monitor system. Analysis of variance demonstrated significant effects of CHPTAC concentration and exhaustion time on the percent exhaustion. Color strength at the end of the dyeing cycle was significantly higher for cationized fabrics compared to the control fabric. This work shows that treatment of cotton with CHPTAC enhanced dye uptake properties due to the introduction of cationic sites and resulted in superior dyeing without the addition of salt.     

Effects of ammonia/ammonium thiocyanate on cotton fabric

The effect of ammonia/ammonium thiocyanate (NH₃/NH₄SCN) treatment of the swelling behavior, structural changes, and physical properties of cotton sheeting was compared with that of sodium hydroxide and liquid ammonia mercerization. Increased percent shrinkage, accessibility to a large dye molecule, dyestuff absorption, swelling with water, and water imbibition showed that NH₃/NH₄SCN had improved the accessibility of the cotton fabric. X-ray diffractograms showed the characteristic Cellulose I crystal lattice. X-ray diffraction and infrared absorption spectroscopy indicated that the crystallite size was unchanged and the swelling from the NH₃/NH₄SCN treatment occurred in the amorphous regions of the cellulose since the observed crystal structure was unchanged. Moisture regain determinations and barium hydroxide absorption suggested that some recrystallization of the cellulose may have occurred from the NH₃/NH₄SCN treatment. Fibers treated with NH₃/NH₄SCN showed a cross sectional shape similar to that of the origianl fibers but with reduced lumen area.     

In vitro and in silico study of Aloe vera leaf extract against human breast cancer

Abstract

Aloe vera leaf contains some bioactive compounds that have a strong binding affinity toward estrogen receptor as compared to standard drug tamoxifen. In this study, we have found that the IC₅₀ of Aloe vera leaf extract against breast cancer cell line (MCF-7) is 23?µg/mL which is much lower than the IC₅₀ (332?µg/mL) of Aloe vera leaf extract against non-cancerous cell line (NIH-3T3). We have also calculated the total concentration of phenolic acid (385.662?µg/mL), flavonoids (160.402?µg/mL) and alkaloids (276.754?µg/mL) in Aloe vera leaf extract. The free radical scavenging activity of Aloe vera leaf extract is 67% to 89% (at 50 to 300?µg/ml). Our virtual molecular docking study suggests that bioactive compounds like Aloe-emodin (?8.8?Kcal/mol), 7-hydroxy-2,5 dimethylchromone (?7.5?Kcal/mol), Beta-sitosterol (?7.3?Kcal/mol) etc. have a greater binding affinity toward estrogen alpha receptor as compared to standard drug Tamoxifen (?6.4?Kcal/mol).