Bright Purple Research Articles

Influence of Critical Parameters on the Extraction of Concentrated C-PE from Thermotolerant Cyanobacteria.

This work aimed to identify the influence of pH, molarity, w/v fraction, extraction time, agitation, and either a sodium (Na2HPO4·7H2O-NaH2PO4·H2O) or potassium buffer (K2HPO4-KH2PO4) used in the extraction of C-phycoerythrin (C-PE) from a thermotolerant strain of Potamosiphon sp. An experimental design (Minimum Run Resolution V Factorial Design) and a Central Composite Design (CCD) were used. According to the statistical results of the first design, the K-PO4 buffer, pH, molarity, and w/v fraction are vital factors that enhance the extractability of C-PE. The construction of a CCD design of the experiments suggests that the potassium phosphate buffer at pH 5.8, longer extraction times (50 min), and minimal extraction speed (1000 rpm) are ideal for maximizing C-PE concentration, while purity is unaffected by the design conditions. This optimization improves extraction yields and maintains the desired bright purple color of the phycobiliprotein.

Rapid detection and differentiation of chlortetracycline and tetracycline by N,P-Ti3C2 QDs

Ti3C2 QDs with good water solubility and photoluminescence properties was prepared by nitrogen and phosphorus doping (N,P-Ti3C2 QDs). The probe has a fluorescence emission peak at 420 nm and emits bright blue fluorescence, which can distinguish and detect two antibiotics with similar structures, chlortetracycline (CTC) and tetracycline (TC). The fluorescence enhancement effect can be realized by the interaction with CTC. The linear range is 2–22 μM, and the detection limit is as low as 0.53 μM. And the change of fluorescent color from bright blue to bright purple can be observed with the naked eye. At the same time, with the addition of TC, the fluorescence of N,P-Ti3C2 QDs can be quenched by static quenching effect, and the fluorescence color changes from bright blue to yellowish green. The detection range is 4.1–20.5 μM, and the detection limit is as low as 0.16 μM.Therefore, on this basis, a strategy for simultaneous detection and recognition of CTC and TC is proposed. The method has been successfully applied to the determination of CTC and TC in milk samples. This paper provides a new detection method for the identification of tetracycline antibiotics and taps the application potential of Ti3C2 QDs in food detection.

Ceropegia strophanthiflora (Apocynaceae—Asclepiadoideae)—a magnificent and rare new species from South Africa at the brink of extinction

We describe a novel species of Ceropegia (Apocynaceae-Asclepiadoideae-Ceropegieae), C. strophanthiflora, from inland of Mtubatuba in northern KwaZulu-Natal, South Africa. The new species is placed in section Chamaesiphon where it appears to be vegetatively and floristically most similar to C. rehmannii (formerly Brachystelma foetidum). Ceropegia strophanthiflora can, however, be readily distinguished from this species by its strikingly colourful greenish-yellow flowers with bright purple markings and purplish-pink vibratile hairs fringing the corolla lobe bases. Most remarkable, however, are the unusually long, slender and twisted corolla lobes much reminiscent of flowers known in Strophanthus; hence the name C. strophanthiflora. There are no other known South African species exhibiting such flamboyant flowers. Concerningly, this spectacular new species may be at the brink of extinction as only very little habitat remains which is under severe anthropogenic threat. Brachystelma tanzaniense, a species with long and slender corolla lobes from Tanzania, is transferred to Ceropegia section Chamaesiphon under the proposed new name C. dodomaensis. Moreover, the blocking name for this transfer, C. tanzaniensis, is reduced to a synonym of C. cordiloba for which we designate a lectotype.

Discovery through citizen science III: Cryptocoryne zamboangensis (Araceae), a new water trumpet discovered in Zamboanga del Norte, Philippines

Cryptocoryne zamboangaensis, is described as a new water trumpet species discovered by citizen scientists in the streams of Zamboanga del Norte, southwestern Philippines. It resembles C. aponogetifolia in having a spathe tube longer than spathe limb, but differs significantly by its ovate, densely verrucose bright purple limb with a narrow collar. A preliminary analysis of the conservation status and a dichotomous key to the species of the genus in the Philippines are provided.

β-Cyclodextrin derived full-spectrum fluorescent carbon dots: The formation process investigation and biological applications

Carbon dots (CDs), a new building unit, have been revolutionizing the fields of biomedicine, bioimaging, and optoelectronics with their excellent physical, chemical, and biological properties. However, the difficulty of preparing excitation-dependent full-spectrum fluorescent CDs has seriously hindered their further research in fluorescence emission mechanisms and biomedicine. Here, we report full-spectrum fluorescent CDs that exhibit controlled emission changes from purple (380 nm) to red (613 nm) at room temperature by changing the excitation wavelength, and the excitation dependence was closely related to the regulation of sp2 and sp3 hybrid carbon structures by β-cyclodextrin-related groups. In addition, by regulating the content of β-cyclodextrin, the optimal quantum yields of full-spectrum fluorescent CDs were 8.97%, 8.35%, 7.90%, 9.69% and 17.4% at the excitation wavelengths of 340, 350, 390, 410 and 540 nm, respectively. Due to their excellent biocompatibility and color tunability, full-spectrum fluorescent CDs emitted bright and steady purple, blue, green, yellow, and red fluorescence in MCF-7 cells. Moreover, we optimized the imaging conditions of CDs and mitochondrial-specific dyes; and realized the mitochondrial-targeted co-localization imaging of purple, blue and green fluorescence. After that, we also explored the effect of full-spectrum fluorescent CDs in vivo fluorescence imaging through the intratumorally, subcutaneously, and caudal vein, and found that full-spectrum fluorescent CDs had good fluorescence imaging ability in vivo.

Eu3+ doped CsPbCl3 perovskite nanocrystalline for flexible and stretchable luminescent film

Flexible luminescent films have great potential for development in various industries and are therefore attracting much attention. Cesium halide lead perovskites still face many problems in terms of stability and toxicity. In this work, Eu3+ ions were used as dopant to synthesize CsPbCl3:Eu3+ perovskite nanocrystals (NCs), and their structure and properties were studied to achieve a reduction in toxicity to the CsPbCl3 nanocrystalline heavy element lead. CsPbCl3:Eu3+ NCs demonstrated improved luminescence performance as well as stable performance. Further, the CsPbCl3:Eu3+ NCs prepared by the heat injection method coated with a layer of TPU film on its surface, showing excellent tensile properties, waterproof properties. CsPbCl3:Eu3+ NCs show a bright purple under the illumination of ultraviolet, providing a new idea matrix for the luminescent film.

Safety and quality of sweet and cream oil of various domestic manufacturers and determining its falsification

The entry of domestic products into European markets has set Ukrainian entrepreneurs the task - to increase their production, ensure safety, quality and competitiveness. The purpose of the study is to assess the safety and quality of sweet butter obtained from various domestic producers, and to determine its falsification by the generally accepted method and the developed patented express method. The object of the study was the assessment of organoleptic, physicochemical, microbiological parameters and falsification of sweet butter obtained from various milk processing enterprises of Ukraine: Lustdorf LLC and Fooddevelopment LLC, Vinnytsia region; TDV "Yagotinsky butter factory"; PE "SIMOL", Kyiv region; State Enterprise "Starokostiantyniv Dairy Plant", Khmelnytsky region. Analytical, organoleptic (appearance, color, consistency, smell, taste) were used to achieve the research goal; physicochemical (mass fraction of moisture, mass fraction of fat, titrated acidity of plasma oil and acidity of fatty phase of oil, mass fraction of sodium chloride, determination of margarine and vegetable fats), microbiological (KMAFАNM, the presence of Escherichia coli bacteria, pathogenic microorganisms, in particular genus Salmonella, species Listeria monocytogenes; molds) and variation-statistical research methods. Developed patented express method for detecting adulteration of sweet cream oil using resorcinol solution in benzene with a mass fraction of 5.0% and concentrated hydrochloric acid can be used in production laboratories at milk and dairy products, supermarkets, wholesale bases, shops and public laboratories. in laboratories of veterinary and sanitary examination in agro-industrial markets. The oil produced by different manufacturers according to organoleptic parameters: appearance, color, texture, smell and taste met the requirements of DSTU 4399: 2005. According to physical and chemical parameters, the samples of sweet butter also met DSTU 4399: 2005, except for sample № 5 (SE "Starokostiantyniv Dairy Plant" of Khmelnytsky region), which showed an increase of + 0.6% by weight of sodium chloride. Research has established the falsification of sweet cream oil according to the developed patented method, according to which the probability in the indicators was 99.9%, produced: TDV "Yagotinsky butter factory" - up to 1.5% (light purple color) oil and "Farm Peasant", manufacturer LLC Food Development "- from 1.6 to 5.0% (bright purple color). Microbiological parameters of sweet butter: KMAFANM, bacteria of the Escherichia coli group, bacteria of the genus Salmonella, species Listeria monocytogenes, as well as molds met the requirements of DSTU 4399: 2005. Key words: sweet and butter, dairy processing enterprises of Ukraine, organoleptic, physicochemical, microbiological indicators, falsification, safety, quality.

Dual-electroactive metal–organic framework nanosheets as negative electrode materials for supercapacitors

Exploring high-efficiency and robust multifunctional negative electrode materials are vital to develop high-performance asymmetric supercapacitors (ASCs). As one class of important functional materials, metal–organic frameworks (MOFs) have been widely applied in adsorption/separation, optoelectronics, sensing, catalysis, and energy storage fields, but they are rarely served as negative electrodes for construction of ASCs. Herein, the novel electrochromic MOFs-based hierarchical nanosheets (called EV-HNSs) that self-assembled from negative electroactive organic viologen ligands and europium ions, are successfully synthesized through a solid-state precursor and surfactant dual-template-directed approach, and employed as negative electrode of supercapacitors. The obtained EV-HNSs show high areal capacity (186.25 mF cm−2 at 1 mA cm−2), excellent cycling stability, and good rate capability under the voltage from −0.9 to −0.1 V (vs. Ag/AgCl), superior to their bulk counterparts. Especially, during the charge and discharge process, such EV-HNSs display a smart potential-correlated electrochromic feature. The color of EV-HNSs electrode turns from colorless to bright purple when the voltage gets negative, and then it can go back reversibly. Their distinct dual-electroactive composition, molecular stacking mode, and hierarchical porous nanosheet assembly structures endow the specific energy storage performance of EV-HNSs. Next, by choosing the electrodeposited MnO2 as positive electrode, the EV-HNSs//MnO2 ASCs are further fabricated, which manifest satisfactory operating voltage (1.55 V) and high areal energy density (9.4 μWh cm−2 at 775 μW cm−2), outperforming most of reported ASCs devices. This work may shed light on developing hierarchical MOFs-nanosheets-based multifunctional negative electrodes, and promote their applications in smart energy storage devices or other clean energy options.

Location probing by males complicates sexual dynamics and successful mate‐guarding in squid groups

Reproductive fitness is defined by the successful passing of an individual's genes to the next generation. Cephalopods that mate in groups, in particular coastal squid and cuttlefish species, have evolved complex sexual tactics in order to maximize reproductive success (Morse and Huffard 2019). Through dynamic skin patterning accompanied by typical body postures, individuals send visual signals in the form of displays to potential mates and rival competitors, often engaging in escalating conflicts (Moynihan and Rodaniche 1982, Mather 2016).

Paleoproterozoic Rajapalot Au-Co system associated with evaporites: Chemical composition and boron isotope geochemistry of tourmaline, and sulfur isotopes of sulfates, Peräpohja belt, northern Finland

The Raja Au-Co mineralization in the Paleoproterozoic Peräpohja belt in northern Finland is part of the wider Rompas-Rajapalot mineralized area with several known Au-Co occurrences. The area is characterized by distinct tourmaline occurrences, spatially associated with Au-Co mineralization. Four texturally distinct tourmaline types were identified although all analysed tourmalines belong to the alkali-group and are classified as dravite. δ 11B values and fractionation modelling indicates that at least two distinct fluids were responsible for the tourmaline formation with initial end member δ11B values of the fluids at −8‰ and −1‰. Possible sources for boron rich fluids are Svecofennian orogeny related (ca. < 1.9 Ga) metamorphic fluids and magmatic-hydrothermal fluids related to the late-orogenic ca. 1.78 Ga granitoids. Structural data from the quartz-tourmaline veins outlines a strong linear trend towards the Raja high-grade mineralization trend. This is interpreted as evidence for structural control of the Raja mineralization, which possibly is contained in shear-zones or within the hinge regions of local high degree folding.A distinctive rock unit with bright purple anhydrite layers and white gypsum veins has been intersected by drilling. While the sulfate-rich unit is unmineralized, the mineralogy and regional geological setting suggests an evaporitic origin. Anhydrite has δ34S values in a narrow range from 8.1 to 9.8 ‰. Gypsum has slightly heavier δ34S from 10.6 to 12.2 ‰. Together with isotope fractionation constraints, textural evidence suggests the authigenic formation of gypsum with SO42- sourced from anhydrite. Significant similarities in textures and sulfur isotope values to well-known evaporite successions of the Onega basin, western Russia, further supports the presence of evaporitic strata within the Peräpohja belt.

Synthesis of high-performance copper barium silicate composite pigment from waste iron ore tailings

Iron ore tailings (IOT) is a kind of solid waste that is a mixture of a variety of non-metallic minerals. However, the research on preparing functional materials by virtue of the endowment characteristics of its non-metallic mineral mixture is still at the beginning. Herein, bright purple copper barium silicate (BaCuSi2O6) composite pigment was prepared by IOT, sodium silicate, Cu2+ and Ba2+ via a simple and mild one-step hydrothermal method. In the process, the structure of IOT was decomposed and acted as a silicate resource and carrier. The presence of IOT enhanced the crystallinity of BaCuSi2O6 and improved its dispersibility. At a Ba:Cu:Si molar ratio of 1:1:8 and hydrothermal temperature of 200 °C, the obtained BaCuSi2O6 composite pigment exhibited the most vivid purple color (L* = 55.7, a* = 25.3, b* = −46.6), which is much better than the commercial cobalt violet pigment (L* = 46, a* = 33, b* = −32). Moreover, the theoretical content of IOT in composite pigment was 36.17 wt%, which significantly reduces the synthesis cost of the purple composite pigment.

Crystal structure, Hirshfeld surfaces and energy frameworks of 5,10,15,20-tetrakis (4-ethylphenyl) porphyrin

Abstract A novel porphyrin based on 5,10,15,20-tetrakis(4-ethylphenyl) porphyrin (TEPP) was analyzed by X-ray diffraction techniques. This compound crystallizes as a bright purple block in the monoclinic system, space group P21/n, with a = 10.4224 (12) A, b = 9.5711 (9) A, c = 21.2750 (2) A, β = 102.488 (11) °, V = 2072.1 (4) A3 and Z = 2. The refinement converged to R1(F) = 0.0675, wR2(F2) = 0.2605 and S = 1.050. The supramolecular packing array involves N–H···N hydrogen bonds, H···π and π···π interactions. Hirshfeld surface analysis revealed that the H···H (70.0%) interactions have a major contribution to the molecular surface. The energy frameworks were computed using the basis set B3LYP/6–31G(d,p) and, using this model the electrostatic, polarization, dispersion and repulsion energies were determined, as well as the interaction energies for all molecular units within of a sphere 3.8 A around the central molecule. The dispersion energy (E'dis =-225.7 kJ/mol) framework is dominant over the electrostatic energy ((E'ele=-35.5 kJ/mol) framework.

An Improved Polymerase Cross-Linking Spiral Reaction Assay for Rapid Diagnostic of Canine Parvovirus 2 Infection.

With increasing complications of canine parvovirus infection cases, disease diagnosis and treatment have become more difficult. In this study, specificity primers for the conserved region of the VP2 gene of canine parvovirus 2 (CPV-2) were synthesized and evaluated. An improved polymerase cross-linking spiral reaction (PCLSR) method for early and rapid diagnosis of CPV-2 was established. The results showed that the amplification reaction was optimal when run at 62°C for 50 min and could be used to detect CPV-2 without any cross-reactions with other pathogens of canine infectious diseases. Reaction results were directly judged by the naked eyes, with the positive amplification tube shown as luminous yellow and the negative tube as bright purple. Compared with the previously reported polymerase spiral reaction (PSR) method for CPV-2 detection, this reaction was performed using improved primer pairs and a better dye identification method (using an indicator comprising phenol red and cresol red). The detection limit of PCLSR was 3.9 × 101 copies using gel electrophoresis or a visible dye. The positive rate of 132 clinical samples was 42.42%, which was identically the same as that of the PSR method and slightly higher than that of the colloidal gold strip method (39.39%). The newly developed CPV-PCLSR assay shows the advantage of rapid visualization of results and offers a convenient and rapid method for early CPV-2 diagnosis with higher sensitivity and specificity than the established methods.

Invisible Inks for Secrecy and Anticounterfeiting: From Single to Double-encryption by Hydrochromic Molecules.

Secret information recorded by traditional single-encrypted invisible inks is easily cracked because the inks can switch only between "NONE" and "TRUTH". Developing double-encrypted systems makes the information reversibly switchable between "FALSE" and "TRUTH", which is helpful to ensure the safety of the secret information during transport. Here, we prepared heat-developed invisible inks by hydrochromic molecules donor-acceptor Stenhouse adducts (DASAs) and oxazolidines (OXs) and promoted the invisible inks from single to double encryption. DASAs coordinate with water molecules and form stable colorless cyclic DASA·xH2O molecules, which lose coordinated water molecules after heating and switch to colored linear DASAs. In contrast, OXs are colored with water and are colorless after heating. Single-encrypted secrecy was realized by DASA invisible inks. The information is invisible under the encrypted state and becomes bright purple after heating. Vapor treating re-encrypted the information in ∼5 min. Furthermore, the single-encryption was promoted to double-encryption by a DASA/OX invisible inks system. Heating and vapor treating switch the information between the "FALSE" and "TRUTH" reversibly. The DASA/OX invisible ink system is applied for secrecy of texts, graphic images, and quick response (QR) codes.

Photosynthetic Profiles of Green, Purple, and Spotted-Leaf Morphotypes of Tipularia discolor (Orchidaceae)

Three morphotypes of Tipularia discolor (Cranefly Orchid) occur sympatrically in the piedmont of North Carolina, producing leaves with upper (adaxial) surfaces that are either green, purple, or green with purple spots; all leaves exhibit bright purple lower (abaxial) surfaces. The basis for differences in coloration between individuals in this species is unknown. Because leaf purpling is often a sign of physiological stress, we hypothesized that adaxially purple and/or spotted individuals would exhibit reduced photosynthetic capacity compared to adaxially green individuals, and that adaxially purple tissues would exhibit symptoms of shade acclimation relative to adaxially green tissues (consistent with a photoprotective function of anthocyanin pigments). We made the following measurements on samples of the 3 morphotypes: photosynthetic response to light and intercellular CO2, monthly photosynthetic gas exchange and chlorophyll fluorescence, and quantification of foliar pigments (chlorophylls, xanthophylls, and anthocyanins). Inconsistent with both hypotheses, the 3 morphotypes did not differ in any of the parameters measured, except anthocyanin content. Furthermore, corms continued to produce leaves with the same pigment patterns in subsequent years, even when sunlight, fertilizer, and water were controlled for in a greenhouse setting. We conclude that leaf purpling and spotting in Cranefly Orchid are most likely not related to physiological stress, and are more likely genetic in nature, perhaps representing alternative phenotypic adaptations related to herbivory defense.

A new forest dwelling button spider from South Africa (Araneae, Theridiidae, Latrodectus).

The medically important spider genus Latrodectus Walckenaer 1805, commonly referred to as "button spiders" in South Africa, is represented by six species in the country. Using morphology and the COI barcoding gene we describe a new forest dwelling species,Latrodectus umbukwane n. sp. Wright, Wright, Lyle and Engelbrecht. Females have red markings on both the ventral and posterior dorsal surfaces of the abdomen, parallel spermathecae and three loops of the copulatory ducts. Males have an embolus with four loops and diagnostic white markings on the ventral surface of the abdomen that darken with age. Egg sacs are smooth, large, and bright purple when freshly laid, turning shiny grey with time. Latrodectus umbukwane n. sp.is known only from sand forest vegetation types in northern Zululand, KwaZulu-Natal, South Africa. A predicted geographic distribution for this species is provided based on cartographic mapping of known habitat and altitudinal preference, from which area of occupancy (AOO; 698 km2) and extent of occurrence (EOO; 4963 km2) were calculated to assess potential IUCN Red List status. Due to the uncertainty of the distribution of this species, a Red List status of Data Deficient (DD) is recommended. An updated key to the southern African species of Latrodectus is provided.

IDENTIFIKASI TANAMAN HANJUANG (CORDYLINE FRUTICOSA) DI KEBUN RAYA BOGOR SEBAGAI TANAMAN LANSKAP BERDASARKAN MORFOLOGI DAN ANATOMINYA

Hanjuang (Cordyline fruticosa) is perennial plant which has function as protective plant and barrier in rice fields or fields. The research purpose was to determine Hanjuang (Cordyline fruticosa) plant based on morphology and anatomy. The research method used was descriptive qualitative. Samples were taken at Bogor Botanical Gardens. The anatomy Observed under microscope light with magnification 100-400 times. The research resulted that leaves morphology showed pointed apical and base, arrangement pinnate bones, flesh like paper, lanceolate shape, smooth surface, choppy edges, bright purple when exposed to sunlight and purple when is not, and type leaf sheath. Moreover, leaves, stems, and roots have support tissue in form of colenchyma. The anatomy of stem and root showed transport tissue but xylem observed larger than its phloem. Root showed radially shape. Leaves has an actinositic stomata and content ergastic in the form of needle crystals. Leaves could be seen purple in water and changes when to yellow and green after some drops of basic solutions. It showed that Hanjuang (Cordyline fruticosa) leaves contain anthocyanin but no carotenoid.

Development of paper indicator from sambang colok (Aerva sanguinolenta) plant extract

This study aims to develop a paper indicator from Aerva sanguinolenta plant extract. The experimental method is used including the analysis of the dye, the extraction of various solvents, the test of the phenolic compound, and the absorbance measurement of the UV-Vis spectrophotometry of the plant extract, and the creation of indicator paper by absorbing the extract of A. sanguinolenta, and testing it on the pH range of 1-14. The experimental results show that the indicator made from coarse filter paper with ethanol extract of the polypropylene binder of the decoction product has the best characteristic shown by the absorbance of 1,186 ppm of bright purple anthocyanin. The resulting color change range is evident from purple to yellow in the pH range 11-12. This research is expected to facilitate the teacher using indicator paper in practice.

Understanding Color Polymorphism in the Sea Star, Pisaster ochraceus, Through Activity Levels and Dietary Preference

Color polymorphism is found in a wide array of organisms ranging from copepods to black bears. Pisaster ochraceus, an intertidal sea star on the North Pacific West Coast, shows a striking color polymorphism including a range of orange, brown, maroon, and purple. Pisaster shows extensive geographic color variation, with &gt;95% frequency of bright purple Pisaster in the Vancouver region; while the open pacific coast has a frequency distribution of 6-28% orange, 68-90% reddish-brown to dull purple, and a small percentage of bright purple. Maintenance of color polymorphism remains unknown, but one hypothesis suggests an underlying genetic component with regional-scale variation controlled by an ecological factor. Two ecological factors suggested are diet and salinity. This study analyzes the differences in dietary preference and activity levels between the color morphs in Bamfield, British Columbia. Pisaster was binned into two colors, orange and purple, for statistical analysis. Feeding laboratory trials showed no preference between the color morphs for Mytilus edilus or Mytilus californianus. Self-righting trials were performed in a low (20 psu) and controlled (35 psu) salinity and no significant difference was found between the color morphs. Interestingly, the activity levels of orange color morphs were not significantly different between low and control salinity. The results suggest there are ecological differences between the color morphs that still need to be evaluated.

Development of edible films from tapioca starch and agar, enriched with red cabbage (Brassica oleracea) as a sausage deterioration bio-indicator

Sausage spoilage has been identified as a cause of some food poisoning cases. Development of a bioindicator film is one of the alternative methods to detect sausage deterioration. The objectives of this paper were to develop a bioindicator edible films (BEF) from tapioca starch (TS), agar, and red cabbage juice (RC), and to evaluate its performance on sausage deterioration detection. The experiment had a 3x3 randomized factorial experimental design (agar: 3, 5, 7% by weight of TS; RC: 10, 15, 20% v/v based on 100% of suspension). Glycerol was used as the plasticizer. The results showed that the addition of agar into the film solution increased the thickness, elongation, and tensile strength, and decreased water vapour transmission rate (WVTR). While the addition of RC increased the thickness, but decreased elongation, tensile strength, and WVTR. BEF consisting of 2% tapioca starch, 7% (w/w) agar and 10 % (v/v) RC was chosen to apply on sausage. It could detect an increase in the microbial population and in the pH variations as result of sausage deterioration at 24, 48, and 72 h shown through color changes of BEF from bright purple at 0 h to light purple, dark purple-blue, and purple-green color respectively.