Effects of clitorienolactones from Clitoria ternatea root on calcium channel mediating hippocampal long-term potentiation in rats induced chronic cerebral hypoperfusion.

Chronic cerebral hypoperfusion (CCH) is a common mechanism of acute brain injury due to impairment of blood flow to the brain. Moreover, a prolonged lack of oxygen supply may result in cerebral infarction or global ischemia, which subsequently causes long-term memory impairment. Research on using Clitoria ternatea root extract for treating long-term memory has been studied extensively. However, the bioactive compound contributing to its neuroprotective effects remains uncertain. In the present study, we investigate the effects of clitorienolactone A (CLA) and B (CLB) from the roots of Clitoria ternatea extract on hippocampal neuroplasticity in rats induced by CCH. CLA and CLB were obtained using column chromatography. The rat model of CCH was induced using two-vessel occlusion surgery (2VO). The 2VO rats were given 10 mg/kg of CLA and CLB orally, followed by hippocampal neuroplasticity recording using in vivo electrophysiological. Rats received CLA and CLB (10 mg/kg) significantly reversed the impairment of long-term potentiation following 2VO surgery. Furthermore, we investigate the effect of CLA and CLB on the calcium channel using the calcium imaging technique. During hypoxia, CLA and CLB sustain the increase in intracellular calcium levels. We next predict the binding interactions of CLA and CLB against NMDA receptors containing GluN2A and GluN2B subunits using in silico molecular docking. Our result found that both CLA and CLB exhibited lower binding affinity against GluN2A and GluN2B subunits. Our findings demonstrated that bioactive compounds from Clitoria ternatea improved long-term memory deficits in the chronic cerebral hypoperfusion rat model via calcium uptake. Hence, CLA and CLB could be potential therapeutic tools for treating cognitive dysfunction.

Bio-enhanced fraction from Clitoria ternatea root extract ameliorates cognitive functions and in vivo hippocampal neuroplasticity in chronic cerebral hypoperfusion rat model.

Research employing a bio-enhanced fraction of Clitoria ternatea (CT) to treat cognitive decline in the animal model has not yet been found. This study aimed to determine the neuroprotective effect of CT root bioactive fraction (CTRF) in chronic cerebral hypoperfusion (CCH) rat model. CTRF and its major compound, clitorienolactones A (CLA), were obtained using column chromatography. A validated HPLC-UV method was employed for the standardization of CTRF. CCH rats were given orally either vehicle or fraction (10, 20 and 40 mg/kg). Behavioural and hippocampal neuroplasticity studies were conducted following 4 weeks post-surgery. The brain hippocampus was extracted for proteins and neurotransmitters analyses. HPLC analysis showed that CTRF contained 25% (w/w) of CLA. All tested doses of CTRF and CLA (10 mg/kg) significantly restored cognitive deficits and reversed the inhibition of neuroplasticity by CCH. However, only CTRF (40 mg/kg) and CLA (10 mg/kg) significantly reversed the elevation of amyloid-beta plaque. Subsequently, treatment with CTRF (40 mg/kg) and CLA (10 mg/kg) alleviated the downregulation of molecular synaptic signalling proteins levels caused by CCH. The neurotransmitters level was restored following treatment of CTRF and CLA. Our finding suggested that CTRF improves memory and neuroplasticity in CCH rats which was mainly contributed by CLA.

The influence of aqueous butterfly pea (Clitoria ternatea) flower extract on active and intelligent properties of furcellaran Double-Layered films - in vitro and in vivo research.

Innovative, intelligent and active double-layer films, based on furcellaran and with the addition of gelatin hydrolysates, have been obtained for the first time. An aqueous extract of clitoria flower in 3 concentrations was included in the 1st FUR layer. The films demonstrated strong antimicrobial effects, but did not exhibit fungicidal properties. The antioxidant properties of the films were within the range of 2.27-3.92 mM Trolox/mg (FRAP method) and 36.67-61.24 % (DPPH method). The films were used as active packaging materials in salmon fillets, which were stored for a period of 12 days in 4 °C. Analysis concerning microbiological properties of the stored fillets showed the possibility of extending their shelf-life by 6 days. Lipid oxidation, determined by TBARS has delayed. The obtained films are a promising material for the packaging industry. This is an important aspect within the context of global food waste and also the need to reduce synthetic materials.

Chemical constituents and in vivo preliminary evaluation of the toxicological activity of Ouratea spectabilis (OCHNACEAE) and Clitoria guianensis (Fabaceae) leaves

Clitoria guianensis and Ouratea spectabilis, found in the Brazilian Cerrado, are used in folk medicine, despite the few chemical and biological studies reported in the literature. The present study aims to investigate the toxicity and effect of extracts from both species on the microcrustacean Artemia salina, and to determine the chemical composition of the hexane extract of O. spectabilis leaves and the EtOAc fraction of C. guianensis leaves. Kaempferitrin, a flavonoid isolated from of the EtOAc fraction of C. guianensis leaves, was identified by chemical analysis. Analysis of the hexane extract of O. spectabilis leaves using gas chromatography-mass spectrometry (GC-MS) suggested the presence of twenty-five known substances. The Hex, EtOAc, and EtOH crude extracts of C. guianensis leaves exhibited high and moderate toxicity against Artemia salina, with median lethal dose values (LD50) of 43.7, 25.4, and 233.4 mg.L−1, respectively. The acetone extract of O. spectabilis leaves showed moderate toxicity against Artemia salina with an LD50 value of 115.13 mg.L−1.

Phytochemical Properties and In Vitro Biological Activities of Phenolic Compounds from Flower of Clitoria ternatea L.

Phenolic compounds from the flower of Clitoria ternatea L. (PCFCTL) were extracted using a high-speed shearing extraction technique and purified by AB-8 macroporous resins, and the phytochemical composition of the purified phenolic compounds from the flower of Clitoria ternatea L. (PPCFCTL) was then analyzed. Subsequently, its bioactivities including antioxidant properties, enzyme inhibitory activities, and antiproliferative activities against several tumor cell lines were evaluated. Results indicated that the contents of total phenolics, flavonoids, flavonols, flavanols, and phenolic acids in PPCFCTL were increased by 3.29, 4.11, 2.74, 2.43, and 2.96-fold, respectively, compared with those before being purified by AB-8 macroporous resins. The results showed PPCFCTL have significant antioxidant ability (measured by reducing power, RP, and ferric reducing antioxidant power method, FRAP) and good DPPH, ABTS+, and superoxide anion radical scavenging activities. They can also significantly inhibit lipase, α-amylase, and α-glucosidase. In addition, morphological changes of HeLa, HepG2, and NCI-H460 tumor cells demonstrated the superior antitumor performance of PPCFCTL. However, the acetylcholinesterase inhibitory activity was relatively weak. These findings suggest that PPCFCTL have important potential as natural antioxidant, antilipidemic, anti-glycemic and antineoplastic agents in health-promoting foods.

Antioxidant, cytotoxic, and antibacterial activities of Clitoria ternatea flower extracts and anthocyanin-rich fraction.

Clitoria ternatea flower is a traditional medicinal herb that has been used as a natural food colourant. As there are limited studies on investigating the bioactivities of the anthocyanin-rich fraction of Clitoria ternatea flower, this study aimed to determine an efficient column chromatography method to obtain the anthocyanin-rich fraction from this flower and characterise its composition, antioxidant, antibacterial, and cytotoxic activities. Amberlite XAD-16 column chromatography was more efficient in enriching the total anthocyanin content (TAC) of the fraction with the highest TAC to total phenolic content (TPC) ratio of 1:6 than that using C18-OPN. A total of 11 ternatin anthocyanins were characterised in the anthocyanin-rich fraction by LC-MS analysis. The antioxidant activity of the anthocyanin-rich fraction was more potent in the chemical-based assay with an IC50 value of 0.86 ± 0.07 mg/mL using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay than cellular antioxidant assay using RAW 264.7 macrophages. In vitro cytotoxicity assay using human embryonic kidney HEK-293 cell line showed the anthocyanin-rich fraction to be more toxic than the crude extracts. The anthocyanin-rich fraction had more potent antibacterial activity than the crude extracts against Bacillus cereus, Bacillus subtilis, and Escherichia coli. The anthocyanin-rich fraction of C. ternatea has the potential to be used and developed as a functional food ingredient or nutraceutical agent.

Rotenoids from Clitoria fairchildiana R. Howard (Fabaceae) seeds affect the cellular metabolism of larvae of Aedes aegypti L. (Culicidae).

Non-domesticated species may represent a treasure chest of defensive molecules which must be investigated and rescued. Clitoria fairchildiana R. Howard is a non-domesticated Fabacea, native from the Amazonian Forest whose seeds are exquisitely refractory to insect predation. Secondary metabolites from these seeds were fractionated by different organic solvents and the CH2Cl2 fraction (CFD - Clitoria fairchildiana dichloromethane fraction), as the most toxic to 3rd instar Aedes aegypti larvae (LC50 180 PPM), was subjected to silica gel chromatography, eluted with a gradient of CH2Cl2: MeOH and sub fractioned in nine fractions (CFD1 - CFD9). All obtained fractions were tested in their toxicity to the insect larvae. Two rotenoids, a 11α-O-ß-D-glucopyranosylrotenoid and a 6-deoxyclitoriacetal 11-O-n-glucopyranoside, were identified in the mixture of CFD 7.4 and CFD 7.5, and they were toxic (LC50 120 PPM) to 3rd instar Ae. aegypti larvae, leading to exoskeleton changes, cuticular detachment and perforations in larval thorax and abdomen. These C. fairchildiana rotenoids interfered with the acidification process of cell vesicles in larvae midgut and caused inhibition of 55% of V-ATPases activity of larvae treated with 80 PPM of the compounds, when compared to control larvae. The rotenoids also led to a significant increase in the production of reactive oxygen species (ROS) in treated larvae, especially in the hindgut region of larvae intestines, indicating a triggering of an oxidative stress process to these insects.

Spectral Characteristic, Storage Stability and Antioxidant Properties of Anthocyanin Extracts from Flowers of Butterfly Pea (Clitoria ternatea L.).

Anthocyanins from flowers of the butterfly pea (Clitoria ternatea L.) are promising edible blue food colorants. Food processing often faces extreme pHs and temperatures, which greatly affects the color and nutritional values of anthocyanins. This study explored the color, spectra, storage stability, and antioxidant properties of C. ternatea anthocyanin extract (CTAE) at different pHs. The color and absorption spectra of CTAEs at a pH of 0.5-13 were shown, with their underlying structures analyzed. Then, the storage stability of CTAEs were explored under a combination of pHs and temperatures. The stability of CTAE declines with the increase in temperature, and it can be stored stably for months at 4 °C. CTAEs also bear much resistance to acidic and alkaline conditions but exhibit higher thermal stability at pH 7 (blue) than at pH 0.5 (magenta) or pH 10 (blue-green), which is a great advantage in food making. Antioxidant abilities for flower extracts from the butterfly pea were high at pH 4-7, as assessed by DPPH free radical scavenging assays, and decreased sharply when the pH value exceeded 7. The above results provide a theoretical basis for the application of butterfly pea flowers and imply their great prospect in the food industry.

Cationic Clitoria ternatea Seed Peptide as a Potential Novel Bioactive Molecule.

BACKGROUND: While several biologics have been reported from different parts of Clitoria ternatea, a herbaceous climber of the family Fabaceae, specific production of cationic peptides other than cyclotides (<3.7 kDa) has barely been investigated, or their bioactive potential been looked into. OBJECTIVE: The study aims to uncover potential bioactivities and characteristics of novel cationic peptides from C. ternatea seeds. METHODS: C. ternatea seed cationic peptide purified by simple and cost-effective procedures was analyzed by electrophoresis and mass spectrometry. Antimicrobial efficacy was evaluated against bacterial and fungal pathogens. Antioxidant potential was quantified by in vitro antioxidant assays. Physicochemical characterization and Tandem mass spectrometry were performed. RESULTS: An 8.5 kDa cationic peptide purified from C. ternatea seeds was active against Candida albicans, Staphylococcus aureus, Aeromonas hydrophila and Escherichia coli at a minimum inhibitory concentration in the range of 8-32 µg/ml. This activity was totally uncompromised at pH 5-8 or after 1 h of heat treatment at 70-80ºC, but was sensitive to protease treatment. Concentration-dependent free-radical scavenging activity and ferric-reducing capacity demonstrated the antioxidant potential of the peptide. Tandem MS analysis of trypsin-digested peptide based on shotgun proteomics detected matching peptide sequences with one or two cysteine residues but had low sequence coverage (≤17%) to known sequences in the C. ternatea protein database. Taken together, the distinct characteristics of this novel 8.5 kDa peptide clearly distinguish it from known cyclotides of C. ternatea. CONCLUSIONS: Insights have been obtained into the functional characteristics of what appears to be a novel cationic peptide from C. ternatea seeds, exhibiting significant antimicrobial and antioxidant activities.

Identification of Anthocyanin Compounds in Butterfly Pea Flowers (Clitoria ternatea L.) by Ultra Performance Liquid Chromatography/Ultraviolet Coupled to Mass Spectrometry.

Butterfly pea flower have great sensory attraction, but they have not yet been used widely in Vietnam. Extracts of butterfly pea flowers can be used conveniently as a natural blue colorant for food products. In this study, the identification of anthocyanin compounds in butterfly pea flowers was performed by UPLC coupled with a UV and Mass spectrometer instrument. Positive and negative ion electrospray MS/MS chromatograms and spectra of the anthocyanin compounds were determined. By analyzing the chromatograms and spectra for each ion, five anthocyanins were identified in the butterfly pea flower extract; these were delphinidin-3-(6″-p-coumaroyl)-rutinoside, cyanidin 3-(6″-p-coumaroyl)-rutinoside, delphinidin-3-(p-coumaroyl) glucose in both cis- and trans- isomers, cyanidin-3-(p-coumaroyl-glucoside) and delphinidin-3-pyranoside. Additionally, based on their intensity, it was determined that cyanidin-3-(p-coumaroyl-glucoside) was the most abundant anthocyanin, followed by cyanidin 3-(6″-p-coumaroyl)-rutinoside, delphinidin-3-(p-coumaroyl-glucoside), delphinidin-3-(6″-p-coumaroyl)-rutinoside and delphinidin-3-pyranoside. In this study, cyanidin derivatives were discovered in butterfly pea flower extract, where these compounds had not been detected in previous studies.

Clitorienolactones and Isoflavonoids of Clitorea ternatea Roots Alleviate Stress-Like Symptoms in a Reserpine-Induced Zebrafish Model.

Clitorea ternatea has been used in Ayurvedic medicine as a brain stimulant to treat mental illnesses and mental functional disorders. In this study, the metabolite profiles of crude C. ternatea root extract (CTRE), ethyl acetate (EA), and 50% aqueous methanol (50% MeOH) fractions were investigated using ultrahigh-performance liquid chromatography-diode array detector-tandem mass spectrometry (UHPLC-DAD-MS/MS), while their effect on the stress-like behavior of zebrafish, pharmacologically induced with reserpine, was investigated. A total of 32 compounds were putatively identified, among which, a series of norneolignans, clitorienolactones, and various flavonoids (flavone, flavonol, isoflavone, and isoflavanone) was found to comprise the major constituents, particularly in the EA and 50% MeOH fractions. The clitorienolactones, presently unique to the species, were present in both the free and glycosylated forms in the roots. Both the EA and 50% MeOH fractions displayed moderate effects on the stress-induced zebrafish model, significantly decreasing freezing duration and elevating the total distance travelled and average velocity, 72 h post-treatment. The results of the present study provide further evidence that the basis for the use of C. ternatea roots in traditional medicine to alleviate brain-related conditions, such as stress and depression, is attributable to the presence of clitorienolactones and the isoflavonoidal constituents.

Mass Spectrometric Analysis of Cyclotides from Clitoria ternatea: Xxx-Pro Bond Fragmentation as Convenient Diagnostic of Pro Residue Positioning.

Cyclotides, a class of macrocyclic plant peptides, characterized by a cyclic backbone and three inter-locking disulfide bonds, may be divided into two major structural subfamilies, Möbius and Bracelet, based on the presence or absence of a specific proline residue. The present study describes the suite of cyclotides obtained from Clitoria ternatea, characterized by LC-MS and MS/MS techniques. Notable variations in product ion distributions were observed in cyclotides belonging to different structural subfamilies based on the number and positions of proline residues. For instance, Cter M which is an abundant Möbius cyclotide in this plant containing three proline residues, displayed distinct b- and y- ion characteristics in the MS/MS spectra compared to Cliotide T1, another commonly identified cyclotide but belonging to the Bracelet subfamily having two proline residues. The distinct fragmentation pattern of prototypical cyclotides of each structural subfamily, determined by Xxx-Pro bond fragmentation, was used to rapidly identify and sequence a novel cyclotide ctr pep 30 from this plant.

Chitosan-poly(vinyl alcohol) intelligent films fortified with anthocyanins isolated from Clitoria ternatea and Carissa carandas for monitoring beverage freshness.

Biodegradable chitosan-poly(vinyl alcohol) films containing natural anthocyanin-rich extracts were prepared using solvent casting method and employed as intelligent indicators for monitoring beverages freshness. The surface and cross-sectional scanning electron micrograph indicated a compact structure for the intelligent films, whereas the atomic force micrograph indicated a 16.22 and 20.31 nm increase in surface roughness for Clitoria ternatea and Carissa carandas extract incorporated films, respectively. Moreover, the test films demonstrated enhanced radical scavenging efficacy. The extracts and anthocyanin incorporated films presented excellent colorimetric changes at pH 2 to 8. In addition, the C. ternatea test films showed changes in color for juice stored at 25 °C after 72 h. Photo-degradability results indicated stability of test films stored in dark at 4 °C and 25 °C, whereas leaching study indicated the release of ≤2.0% anthocyanin after 24 h. The cytocompatibilty assay showed that the test and control films were biocompatible with a viability of >80% on HaCat cells. The results demonstrated that the incorporation of anthocyanins-rich extracts into chitosan-poly(vinyl alcohol) did not significantly interfere with the films properties (p > 0.05). The natural anthocyanin incorporated films demonstrated good pH sensing property that could be further explored for monitoring of beverages freshness.

Protective role of Clitoria ternatea L. flower extract on methylglyoxal-induced protein glycation and oxidative damage to DNA.

BACKGROUND: Methylglyoxal (MG) is a highly reactive dicarbonyl precursor for the formation of advanced glycation end products (AGEs) associated with age-related diseases, including diabetes and its complications. Clitoria ternatea L. flower has been reported to possess antioxidant and antiglycating properties. Evidence indicates that the extract of Clitoria ternatea L. flower inhibits fructose-induced protein glycation and oxidative damage to bovine serum albumin (BSA). However, there is no evidence to support the inhibitory effect of CTE against MG-mediated protein glycation and oxidative damage to protein and DNA. Therefore, the aim of the present study was to investigate whether C. ternatea flower extract (CTE) prevents MG-induced protein glycation and oxidative DNA damage. METHODS: The formation of fluorescent AGEs in BSA was evaluated using spectrofluorometer. The protein carbonyl and thiol group content were used for detecting protein oxidation. DNA strand breakage in a glycation model comprising of MG, lysine and Cu2+ or a free radical generator 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) systems was investigated using gel electrophoresis. Generation of superoxide anions and hydroxyl radicals in the MG/lysine system was assessed by the cytochrome c reduction assay and thiobarbituric acid reactive substances assay, respectively. High performance liquid chromatography (HPLC) was used to measure the MG-trapping ability. RESULTS: In the BSA/MG system, CTE (0.25-1 mg/mL) significantly inhibited the formation of fluorescent AGEs and protein oxidation by reducing protein carbonyl content as well as preventing the protein thiol depletion. The concentration of CTE at 0.125-1 mg/mL prevented oxidative DNA cleavage in MG/lysine and AAPH systems associated with the inhibition of superoxide anion and hydroxyl radical formation. It also directly trapped MG in a concentration-dependent manner, ranging from 15 to 43%. CONCLUSIONS: The study findings suggest that the direct carbonyl trapping ability and the free radical scavenging activity of CTE are the underlying mechanisms responsible for the prevention of protein glycation and oxidative DNA damage.

Active and intelligent gellan gum-based packaging films for controlling anthocyanins release and monitoring food freshness.

Active and intelligent packaging films with multiple functions including antioxidant, antibacterial and colorimetric pH indicator properties were developed by incorporating Clitoria ternatea (CT) extract into gellan gum (G) film. G enhanced the stability of CT anthocyanins and allowed the anthocyanins to release from G film in a pH-responsive behavior. Heat-treated soy protein isolate (HSPI) was able to interact with G and CT anthocyanins through the formation of electrostatic forces and covalent bonds. G film blended with HSPI greatly reduced the swelling capacity of G/HSPI composite film and controlled the anthocyanins release at pH greater than 6.0. The physical and mechanical properties of G films such as hydrophobicity, water vapor permeability, swelling capacity and tensile strength were also significantly modified by addition of HSPI to G films. The smart films changed their color with the increase of total volatile basic nitrogen (TVBN) values during progressive spoilage of shrimp, revealing their potential application for monitoring seafood freshness.

Behavioral effects induced by organic insecticides can be exploited for a sustainable control of the Orange Spiny Whitefly Aleurocanthus spiniferus.

The Orange Spiny Whitefly (OSW) Aleurocanthus spiniferus (Hemiptera: Aleyrodidae) represents a new serious threat to Citrus spp., grapevine and ornamental plants in the whole Mediterranean area. Such threat urgently calls for the development of a sustainable control strategy, including insecticides compatible with biological control, and applicable also in organic citrus farming that represent an essential part of Mediterranean agricultural economy. Therefore, we evaluated the toxicity and the effects on host searching, oviposition, and probing and feeding behavior exerted on OSW by organic insecticides supposed to have limited side effects on environment and ecosystem services, i.e. sweet orange essential oil (EO), extract of Clitoria ternatea (CT), mineral oil, pyrethrin and azadirachtin. Despite none of the compounds caused a significant mortality of any of the OSW instars, we observed interesting effects on whitefly behavior: (i) EO and pyrethrin showed a relevant repellent effect, with impairment of both adults landing and oviposition on treated plants; (ii) CT and pyrethrin strongly affected probing behavior. Here, in the light of our findings, we discuss possible OSW sustainable control strategies and further research perspectives.

Phenolic composition by UHPLC-Q-TOF-MS/MS and stability of anthocyanins from Clitoria ternatea L. (butterfly pea) blue petals.

The aim of the present study was to evaluate the phenolic composition of crude lyophilized extracts (CLE) and partially purified (PPE) extracts of C. ternatea blue petals as well as the anthocyanin stability against pH, temperature and light in the presence and absence of fructooligosaccharides. Twelve compounds were tentatively identified by UHPLC-Q-TOF-MS/MS in CLE and PPE extracts. In direct/reverse spectrophotometric titration, anthocyanins showed colour changes between pH 2.25 to 10.20, and colour reversibility, maintaining antioxidant activity against the DPPH radical. The aqueous extracts at pH 3.6 and 5.4 exhibited thermal stability with the presence and absence of fructooligosaccharides with activation energy higher than 99 kJ/mol. The addition of fructooligosaccharides in the extracts at pH 5.4 exposed to light provided a protective effect against anthocyanin photodegradation. The data show the technological potential of aqueous extract of C. ternatea blue petals as a natural colourant in a functional beverage model system.

Butterfly pea (Clitoria ternatea) extract as a green analytical tool for selective colorimetric detection of bisulphate (HSO4-) ion in aqueous medium.

The blue color of butterfly pea (Clitoria ternatea) was extracted by Milli-Q water and evaluated for selective detection of bisulphate (HSO4-) ions. The stability of the Clitoria ternatea extract was established by UV-visible and fluorescence techniques. The blue water extract from Clitoria ternatea selectively recognizes HSO4- ions over various anions via a distinct visual color change from blue to purple with a significant hypsochromic shift of 68 nm in the UV-visible absorption spectra. Thus Clitoria ternatea extract provides a selective real time colorimetric monitoring of HSO4- ions which would pave the way for the development of low cost green analytical tool. This type of detection technique enhances the environmental and economic benefits and can emerge as an alternative form of synthetic chelating sensors.

Removal of rhodamine 6G from synthetic effluents using Clitoria fairchildiana pods as low-cost biosorbent.

Many organic dye pollutants have been identified in rivers and lakes around the world, and concern is growing with them as they cause serious changes in the ecological balance of aquatic environments. One of these dyes is rhodamine R6G, which is very water-soluble and has a high corrosive power. Therefore, Clitoria fairchildiana (CF) pods were used as a biosorbent to remove R6G from synthetic dye effluents. CF was characterized by infrared spectroscopy, thermogravimetric analysis, x-ray diffraction, elemental analysis, Boehm titration, and zero charge point measurements. The influence of various factors, such as solution pH, contact time, adsorbent mass, and concentration of R6G, was studied using batch equilibrium experiments. The optimum contact time to reach equilibrium was found to be 15 min, while the optimum adsorbent dose was 8 g L-1. The maximum adsorption capacity of CF (73.84 mg g-1) was observed at pH 6.4 and 298.15 K. Adsorption kinetics followed a pseudo-second-order law, and the isotherm could be best fitted with a Liu model. The obtained thermodynamic parameters indicate that the adsorption of R6G is spontaneous and enthalpy-driven. We thus conclude that CF is an efficient, green, and readily available biosorbent for dye removal from wastewater.

A Colorimetric pH Sensor Based on Clitoria sp and Brassica sp for Monitoring of Food Spoilage Using Chromametry.

A developed colorimetric pH sensor film based on edible materials for real-time monitoring of food freshness is described. The mixed natural dyes from edible plants Clitoria sp and Brassica sp were extracted and incorporated into ι-carrageenan film as a colorimetric pH sensor film for monitoring food spoilage and its freshness. The color changes of the developed colorimetric sensor film were measured with chromametry and UV-vis spectroscopy, respectively. Experimental results show that colorimetric pH sensor film demonstrated statistically significant differences (p < 0.05) between CIE-L*a*b* coordinates color system indicated that the developed colorimetric sensor film was able to give a gradual change in color over a wide pH range. The color of the colorimetric sensor film also changes discretely and linearly with factors that contribute to food spoilage using shrimp and durian samples. Moreover, the developed colorimetric pH sensor film has the potential to be used as a safe, non-destructive testing and also a flexibly visual method for direct assessment of food freshness indicator during storage.