Major Bands Research Articles

Assessing Chinese-to-English Translation Quality – A Systemic Functional Linguistics Perspective

Translation quality assessment is an important issue in translation teaching and learning, but it has been under-researched in translation studies. Whether a translation is good or not depends largely on a translator’s ability of text analysis. Taking the translation task of TEM8 (Test for English Majors Band 8) in 2023 as an example, this paper presents a pilot project aimed at exploring a systematic way of analyzing translation errors by referring to systemic functional linguistics (SFL). In particular, the paper investigates how SFL-based text analysis of ideational meaning, interpersonal meaning and textual meaning can be used for translation teaching and learning, through comparative analyses of a set of texts, including a Chinese source text, two translation texts from TEM8 in 2023, and an AI-generated literal translation as back translation. The study finds that it is possible to identify, describe and classify translation errors in the translated texts, and more significantly, the resulting error description and classification allows translation teachers a more precise expression of the nature of poor translation or translation errors that would otherwise be simply put as “inadequate” or “awkward” translation, and students a more tangible understanding of what counts as an “excellent” translation. Following the analyses, the paper discusses the pedagogical effects of SFL-based text analysis by conducting a survey and semi-structured interviews with students. The quantitative data show that overall, students held a positive attitude towards translation, and the qualitative data analysis uncovers specific benefits and challenges experienced by the students.

Evaluating serum proteinogram methodologies for the diagnosis of inflammation in fish: Acute and chronic patterns in gilthead seabream (Sparus aurata) injected with λ-carrageenan.

Proteinogram is a semiquantitative method specially used in clinic to separate the serum proteins from patients for use in the diagnosis of diseases. However, this methodology has only been applied very recently with this approach in farmed fish. Thus, the aim of this study was to explore the changes in the serum proteinogram of gilthead seabream (Sparus aurata), after triggering an acute or chronic sterile inflammation. For this, two experiments were carried out: i) Acute inflammation experiment: seabream specimens were injected intramuscularly with 50 μL of λ-carrageenan (0.5 mg fish-1) or buffer (control) and blood samples were collected at 3, 6 and 24 h post-injection; ii) Chronic inflammation experiment: specimens were injected at 0, 7 and 14 days with 500, 250 and 250 μL of λ-carrageenan, respectively (20 mg fish-1) or buffer, and blood samples were collected at 15 days post-injection. In both cases, serum was obtained and processed by electropherograms and HPLC-mass spectrometry. Results of electropherograms of control fish revealed four major proteins of 19.5, 76.3, 104.4, and 156.7 kDa in the serum. These four proteins were correlated with apolipoprotein A-II (II (the counterpart of mammalian albumin, Apo fraction), serotransferrin (β fraction), inter-α-trypsin inhibitor heavy chain H3-like (α1 fraction) and α-2-macroglobulin-like (α2 fraction) according to the results obtained with HPLC-mass spectrometry. In a statistical view (p<0.05), no variations were detected in the four major serum protein bands between the control and the acutely inflamed groups. However, in chronically inflamed fish, the Apo fraction decreased statistically compared to the control group. In contrast, the α1 and α2 fractions were statistically increased in the serum of fish sampled 15 days after λ-carrageenan injection, compared to those found in the control fish. α1 and α2 protein fractions are recognized indicators of inflammation in mammals. Consequently, our study presents a novel method for assessing both acute and chronic λ-carrageenan-induced sterile inflammation in gilthead seabream, which could be applicable to other marine species for diagnostic purposes.

A Preliminary Analysis of Factors Influencing Paragraph Dictation

This study begins with a brief analysis of the impact of six barriers (vocabulary, grammatical knowledge, phonetic comprehension ability, cultural background knowledge, and short-term memory capacity) on the paragraph dictation, component of the Test for English Majors Band 4 (TEM4). The study proposes corresponding strategies to enhance dictation skills, aiming to assist teachers and students in adopting effective training methods, and to boost learning interest and confidence.

Optical properties of carbon dots generated in liquid by pulsed IR laser at 1064 nm

Biocompatible carbon dots (CDs) have been synthesized by the laser ablation of graphite and vegetable carbon (charcoal) placed in a phosphate-buffered saline (PBS) solution. The carbon nanoparticles are produced by a pulsed IR laser beam, operating at 1064 nm, 100 mJ energy, and 3 ns pulse duration, interacting with the carbon matrix placed in the liquid at a 0.2 Hz repetition rate. The ablation rate, in terms of removed carbon mass per laser shot, was evaluated to be about 75.8 ng/pulse and 758 ng/pulse for graphite and charcoal, respectively. Optical and electronic microscopy, UV-Vis spectroscopy, and luminescence measurements were employed to evince the CDs dispersion through its photoluminescence emission. The UV excitation at a 365 nm wavelength induces CDs luminescence in the visible region, as a result of electron transition, at a wavelength band depending on the laser spot size, i.e., of the laser fluence. CDs luminescence emission obtained from charcoal is independent of the laser fluence, showing a major emission peak around 475 nm and a secondary emission peak at 515 nm. CDs luminescence emission obtained from graphite depends on the laser fluence, showing a minor wavelength band, around 474 nm, at high laser fluences and a major wavelength band, around 670 nm, at low laser fluence. The CDs luminescence of the produced biocompatible solution finds many applications in the bio-medical field, as will be presented and discussed.

α-Sr2SiO4:Ce3+, Dy3+, Na+ phosphors with abnormal thermal quenching properties for solid-state lighting applications

There is urgent need of thermally stable phosphors for fabricating high-performance white light emitting diodes (LEDs). In this paper, Sr2SiO4:0.02Ce3+,xDy3+, (0.02+x)Na+ phosphors were successfully synthesized by the solid-state reaction method and their luminescence properties were studied. Phase analysis shows that single-phasic α-Sr2SiO4 was prepared when x was greater than 0.006, while a mixed phase of α-Sr2SiO4 and β-Sr2SiO4 were obtained in the samples with x of 0.006 or less. When excited at 344 nm, there is a major emission band at 380–500 nm corresponding to the 5d-4f transition of Ce3+, and other emission peaks with a dominated one at 575 nm corresponding to the 4F9/2-6H13/2 transition of Dy3+. The as-developed Sr2SiO4:Ce3+,Dy3+,Na+ phosphors exhibit excellent thermal stability. To be specific, the intensity retention rate of 425 and 572 nm at 300 °C is as high as 103.6 % and 89.2 %, respectively. Furthermore, near-ultraviolet (nUV) chip-pumped white LED prototypes were assembled using the co-activated phosphor and commercial green and red phosphors, which demonstrate its great potential in high-power white LEDs for solid-state lighting applications.

Spin-dependent electronic phenomena in heavily-doped monolayer graphene

The controlled manipulation of doping levels in graphene is crucial for advancing next-generation low-power electronics. Owing to its peculiar band structure, graphene's electronic functionalities can be easily tuned by electron doping, resulting in the bandgap openings, orbital hybridization, and induced spin-polarization. Here, we unveil the substantial doping of the graphene layer and the emergence of a significant bandgap by sandwiching a monolayer graphene, supported on ferromagnetic cobalt, between two europium layers. Our angle- and spin-resolved photoemission spectroscopy experiments, accompanied by dedicated density functional theory calculations, demonstrate that single-spin electron pockets form as a result of the hybridization of the topmost europium majority bands with graphene, while hybridization gaps are induced in the graphene π∗ bands by the Eu minority bands. Spin-resolved measurements further emphasize a single-spin dispersionless contribution proximal to the Fermi level, possibly arising from the coupling of single-spin polarized graphene bands to optical phonons. This work provides crucial insights into the phase diagram of heavily doped graphene, with significant potential for the design and development of novel 2D systems.

Characteristics and properties of co-precipitated protein and film based on Bambara groundnut protein isolate and fish skin acid-soluble collagen

Co-precipitated protein (CPP) from Bambara groundnut protein isolate (BGPI) and fish skin acid-soluble collagen (ASC) at different BGPI/ASC ratios (100:0, 75:25, 50:50, 25:75 and 0:100 (v/v)) were prepared and characterized. CPP of BGPI/ASC at ratio of 75:25 had higher solubility at acidic and alkaline pHs, compared to other CPP samples. All CPPs had good emulsifying properties. Based on protein patterns, the combination of major bands from BGPI and ASC in the resulting CPP sample was observed. CPP with BGPI/ASC at ratio of 75:25 showed higher surface hydrophobicity than those of other CPP samples. When the films from CPPs were fabricated, similar tensile strength (p > 0.05) was observed, regardless of BGPI/ASC ratios. Nevertheless, film from CPP with BGPI/ASC ratio of 25:75 had higher elongation at break along with lower water vapor permeability (p < 0.05), compared to other CPP films. All CPP films had bright-yellowish color. Increasing ASC ratio augmented (p < 0.05) light transmission of resulting CPP films. FTIR spectra revealed that all CPP films had the similar pattern and functional groups. Therefore, the co-precipitated BGPI and ASC at appropriate ratio could improve properties of resulting proteins, especially for film forming ability.

Signatures of magnetism control by flow of angular momentum

Exploring new strategies to manipulate the order parameter of magnetic materials by electrical means is of great importance not only for advancing our understanding of fundamental magnetism but also for unlocking potential applications. A well-established concept uses gate voltages to control magnetic properties by modulating the carrier population in a capacitor structure1–5. Here we show that, in Pt/Al/Fe/GaAs(001) multilayers, the application of an in-plane charge current in Pt leads to a shift in the ferromagnetic resonance field depending on the microwave frequency when the Fe film is sufficiently thin. The experimental observation is interpreted as a current-induced modification of the magnetocrystalline anisotropy ΔHA of Fe. We show that (1) ΔHA decreases with increasing Fe film thickness and is connected to the damping-like torque; and (2) ΔHA depends not only on the polarity of charge current but also on the magnetization direction, that is, ΔHA has an opposite sign when the magnetization direction is reversed. The symmetry of the modification is consistent with a current-induced spin6–8 and/or orbit9–13 accumulation, which, respectively, act on the spin and/or orbit component of the magnetization. In this study, as Pt is regarded as a typical spin current source6,14, the spin current can play a dominant part. The control of magnetism by a spin current results from the modified exchange splitting of the majority and minority spin bands, providing functionality that was previously unknown and could be useful in advanced spintronic devices.

Systematic investigation of physical properties of Mg3XO4 (X = Cr, Mn, Fe, Co, Ni); a computational approach

Material development is primarily dependent on their design and theoretical exploration. Density functional theory is a great tool to achieve this goal. Here, Mg3XO4 (X = Cr, Mn, Fe, Co, Ni) are considered in order to reveal their full characteristics using density functional theory. Mg3XO4 (X = Cr, Mn, Fe, Co, Ni) are investigated in terms of their structural, elastic, mechanical, thermodynamic, electronic, and dynamic properties. The formation energies for Mg3XO4 (X = Cr, Mn, Fe, Co, Ni) are found to be negative implying synthesisability and dynamic stability of these materials. The evolution of elastic constants of materials demonstrates that all materials satisfy the Born stability criterion, hence Mg3XO4 (X = Cr, Mn, Fe, Co, Ni) are mechanically stable. Several polycrystalline parameters are derived by using elastic constants and evaluated. All materials are found be brittle, hard (Vickers hardness) and magnetic. They exhibit some degree of anisotropy in Young/Shear modulus and Poisson’s ratio. The electronic band structures for Mg3CrO4, Mg3MnO4 and Mg3FeO4 indicated a semi-metallic nature whereas for Mg3CoO4 and Mg3NiO4 indicated metallic nature because both the majority and minority energy bands cut the Fermi level. The phonon modes are found to be in positive frequencies that confirms dynamical stability. The materials’ free energy, entropy, specific heat capacity, Debye and melting temperatures, minimum thermal conductivity and Grüneisen parameters are also obtained and discussed.

Purification, Structural Characterization, and Anticandidal Activity of a Chitin-Binding Peptide with High Similarity to Hevein and Endochitinase Isolated from Pepper Seeds.

With the emergence of multidrug-resistant microorganisms, microbial agents have become a serious global threat, affecting human health and various plants. Therefore, new therapeutic alternatives, such as chitin-binding proteins, are necessary. Chitin is an essential component of the fungal cell wall, and chitin-binding proteins exhibit antifungal activity. In the present study, chitin-binding peptides isolated from Capsicum chinense seeds were characterized and evaluated for their in vitro antimicrobial effect against the growth of Candida and Fusarium fungi. Proteins were extracted from the seeds and subsequently the chitin-binding proteins were separated by chitin affinity chromatography. After chromatography, two fractions, Cc-F1 (not retained on the column) and Cc-F2 (retained on the column), were obtained. Electrophoresis revealed major protein bands between 6.5 and 26.6kDa for Cc-F1 and only a ~ 6.5kDa protein band for Cc-F2, which was subsequently subjected to mass spectrometry. The protein showed similarity with hevein-like and endochitinase and was then named Cc-Hev. Data are available via ProteomeXchange with identifier PXD054607. Next, we predicted the three-dimensional structure of the peptides and performed a peptide docking with (NAG)3. Subsequently, growth inhibition assays were performed to evaluate the ability of the peptides to inhibit microorganism growth. Cc-Hev inhibited the growth of C. albicans (up to 75% inhibition) and C. tropicalis (100% inhibition) and induced a 65% decrease in cell viability for C. albicans and 100% for C. tropicalis. Based on these results, new techniques to combat fungal diseases could be developed through biotechnological applications; therefore, further studies are needed.

Infrared Spectroscopic Characterization of Early 4d Transition Metal Carbene Cations, ZrCH2+ and NbCH2.

IR multiple-photon dissociation (IRMPD) action spectroscopy is combined with quantum chemical calculations to examine the [M,C,2H]+ species for the early 4d metals, M = Zr and Nb. These ions were formed by reacting laser ablated M+ ions with cyclopropane (c-C3H6) in a molecular beam apparatus. Both IRMPD spectra exhibit one major band near 700 cm-1 and a second weaker band at about twice that wavenumber, more evident when irradiated in focus. The [Nb,C,2H]+ species also has a sharp band at 800 cm-1. Comparison with B3LYP calculations allow assignment of the [M,C,2H]+ structures to agostic carbenes, which is similar to the structures found for the 5d analogues, WCH2+ and TaCH2+. A molecular orbital analysis traces the reasons for the agostic deformation from a classic C2v symmetric carbene.

Seaweed assisted preparation of Fe2O3 nanoparticles and their antiviral studies against White Spot Syndrome Virus (WSSV): In vitro and in silico approach.

In the present study, preparation of Fe2O3 nanoparticles using seaweed Sargassum swartzii extract and characterized using XRD, FTIR, and FE-SEM with EDAX analysis. The crystalline nature of γ-Fe2O3 nanoparticles (hematite powders) were confirmed using XRD. In FT-IR spectra of the Fe2O3 nanoparticles, the major bands at 594 cm−1 and 461 cm−1 observed correspond to the metal‑oxygen (FeO) vibrational modes. The surface morphology of Fe2O3 nanoparticles has been studied by FE-SEM. In vitro toxicity and anti-WSSV activity of Fe2O3 nanoparticles were carried out using the shrimp-insect hybrid cell line (PmLyo-Sf9). The bioactivity of Fe2O3 nanoparticles against the WSSV infected with the PmLyo-SF9 cell line was analyzed through dose-dependent attachment inhibition and virucidal activity at an optimum concentration of 320 μg/mL and confirmed by the expression of viral envelope protein VP28. Further, the computational approach of VP28 envelope protein and Fe2O3 binding affinity was confirmed using molecular docking studies. Hence, the Fe2O3 nanoparticles can be formulated as an anti-viral agent against the aquaculture pathogens in efficient disease control.

Structural and Functional Characterization of New Lipid Transfer Proteins with Chitin-Binding Properties: Insights from Protein Structure Prediction, Molecular Docking, and Antifungal Activity.

Faced with the emergence of multiresistant microorganisms that affect human health, microbial agents have become a serious global threat, affecting human health and plant crops. Antimicrobial peptides have attracted significant attention in research for the development of new microbial control agents. This work's goal was the structural characterization and analysis of antifungal activity of chitin-binding peptides from Capsicum baccatum and Capsicum frutescens seeds on the growth of Candida and Fusarium species. Proteins were initially submitted to extraction in phosphate buffer pH 5.4 and subjected to chitin column chromatography. Posteriorly, two fractions were obtained for each species, Cb-F1 and Cf-F1 and Cb-F2 and Cf-F2, respectively. The Cb-F1 (C. baccatum) and Cf-F1 (C. frutescens) fractions did not bind to the chitin column. The electrophoresis results obtained after chromatography showed two major protein bands between 3.4 and 14.2 kDa for Cb-F2. For Cf-F2, three major bands were identified between 6.5 and 14.2 kDa. One band from each species was subjected to mass spectrometry, and both bands showed similarity to nonspecific lipid transfer protein. Candida albicans and Candida tropicalis had their growth inhibited by Cb-F2. Cf-F2 inhibited the development of C. albicans but did not inhibit the growth of C. tropicalis. Both fractions were unable to inhibit the growth of Fusarium species. The toxicity of the fractions was tested in vivo on Galleria mellonella larvae, and both showed a low toxicity rate at high concentrations. As a result, the fractions have enormous promise for the creation of novel antifungal compounds.

Snakehead Fish, Channa striata (Bloch, 1973), Protein Concentrate: Excellent Recovery of Fish-Based Albumin Source and Its Possible Application for Sperm Capacitation

Snakehead fish protein concentrate (SFC) shows promising recovery of excellent protein content that has broad potential applications, including the future use of its albumin content as a sperm capacitation promoter. However, the quantity of snakehead fish albumin recovered depends on several variables, including the habitat in which the fish thrives, extraction procedures, and the assay employed. To optimise the albumin content retrieved from snakehead fish flesh with more reliable results, multiple protein extraction methods were undertaken through the protein concentrate preparation and analysed using the Bromocresol purple (BCP) albumin assay. Total soluble protein (TSP), albumin level, and albumin proportion were recovered at a significant reduction in an acid solvent when exposed to up to 50 °C heating compared to extractions undertaken without heating. Moreover, the small number of protein bands identified indicates that the combination of acid solvent and heating treatment was similarly damaging. In this study, we detected the presence of albumin in SFC at 32 %, the highest percentage ever recorded employing the BCP assay, following extraction with water solvent without thermal treatment. Using SDS-PAGE and densitometric analysis, the identified putative albumin-related bands from the two major bands at 40 kDa and 47 kDa, containing respective proportions of 57 % and 16 % of the total protein loaded. Although this exploratory work requires additional analysis and purification steps, further research employing the SFC is worth identifying its ability and how this alternative albumin source can replace serum albumin to modulate the capacitation process in mammalian sperm.

In silico analysis: Fulleropyrrolidine derivatives against HIV-PR mutants and SARS-CoV-2 Mpro

Abstract Approximately 37.9 million people living with HIV (PLWH) are at risk of severe consequences from COVID-19. Urgent development of tailored treatments for PLWH, who have historically been excluded from vaccine trials, is crucial. The present study introduces some modified fulleropyrrolidine derivatives with chalcogen atoms (O, S, or Se) and hydroxymethylcarbonyl (HMC) groups to target 11 single and double HIV-1 protease (HIV-PR) mutations and the main protease of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2 Mpro). The inhibitory activities of these derivatives are computationally examined through molecular docking, molecular dynamic simulations for 200 ns, and Lipinski’s rule of five (RO5). Fourier-transform infrared spectroscopy spectra and thermodynamic properties are calculated and analyzed using Density Functional Theory B88-PW91 method. The results indicate that the suggested O-compounds obey three parameters of the RO5 and HMC forms hydrogen bonds with studied viral proteases. Compounds with O and S additives display a high binding affinity with negative binding energy values for HIV-PR mutations (A71V-I84V, V77I-I84V, and I84V-L90M) and SARS-CoV-2 Mpro. The compounds with S and Se additives shift to lower frequencies of the major vibrational bands. Specifically, compound 1, with two oxygen additives, emerges as the most effective in inhibiting both HIV-PR mutations and SARS-CoV-2 Mpro.

Expression and basic biochemical characteristics of recombinant surfactant protein D of bottlenose dolphin (Tursiopstruncatus)

We previously identified surfactant protein D (SP-D) in the bottlenose dolphin Tursiops truncatus as a unique evolutionary factor of the cetacean pulmonary immune system. In this short report, recombinant SP-D of bottlenose dolphin (dSP-D) was synthesized in mammalian cells, and its properties were analyzed in vitro. The recombinant proteins were purified using Ni-carrier or Co-carrier. Sodium dodecyl sulfate poly-acrylamide gel electrophoresis and western blotting revealed a 50 kDa major band with minor secondary bands. Enzyme-linked immunosorbent assay-like methods revealed that recombinant dSP-D bonded to gram-positive and gram-negative bacterial walls. Our findings suggest the clinical usefulness of dSP-D for cetacean pneumonia.

Serum proteinogram of gilthead seabream (Sparus aurata) and European sea bass (Dicentrarchus labrax) as a new useful approach for detecting loss of haemostasis

Proteinograms, a semiquantitative analytical method that separates proteins into multiple bands, have not been explored in teleosts for diagnostic or prognostic purposes. This study aimed to establish reference values for proteinograms in the serum of gilthead seabream (Sparus aurata) and European sea bass (Dicentrarchus labrax), two important farmed fish species in the Mediterranean region. Serum proteins were studied using SDS-PAGE, electropherogram, and HPLC-mass spectrometry. SDS-PAGE analysis revealed four major bands of proteins around 11, 25, 70, and 100 kDa in the serum of gilthead seabream and European sea bass. Electropherogram results showed that a protein with a molecular weight of 76.8 kDa was the most abundant protein in the serum of gilthead seabream, while a peak of 75.5 kDa was the most abundant in European sea bass. HPLC-mass spectrometry detected 87 proteins and 119 proteins in the serum of gilthead seabream and European sea bass, respectively, including α1-globulins, α2-globulins, β-globulins, and γ-globulins. Notably, the albumin sequence was not detected in either of the two species. These results help to characterize the serum protein profile and to establish reference proteinograms for these two fish species. They also provide a basis for the development of novel approaches for the rapid detection of loss of haemostasis due to stress, health disorders or disease in farmed fish.

Epsilon subunit of T-complex protein-1 from Leishmania donovani: A tetrameric chaperonin

The cytosolic T-complex protein-1 ring complex (TRiC), also referred as chaperonin containing TCP-1(CCT), comprising eight different subunits stacked in double toroidal rings, binds to around 10 % of newly synthesized polypeptides and facilitates their folding in ATP dependent manner. In Leishmania, among five subunits of TCP1 complex, identified either by transcriptome or by proteome analysis, only LdTCP1γ has been well characterized. It forms biologically active homo-oligomeric complex and plays role in protein folding and parasite survival. Lack of information regarding rest of the TCP1 subunits and its structural configuration laid down the necessity to study individual subunits and their role in parasite pathogenicity. The present study involves the cloning, expression and biochemical characterization of TCP1ε subunit (LdTCP1ε) of Leishmania donovani, the causative agent of visceral leishmaniasis. LdTCP1ε exhibited significant difference in primary structure as compared to LdTCP1γ and was evolutionary close to LdTCP1 zeta subunit. Recombinant protein (rLdTCP1ε) exhibited two major bands of 132 kDa and 240 kDa on native-PAGE that corresponds to the dimeric and tetrameric assembly of the epsilon subunit, which showed the chaperonin activity (ATPase and luciferase refolding activity). LdTCP1ε also displayed an increased expression upto 2.7- and 1.8-fold in the late log phase and stationary phase promastigotes and exhibited majorly vesicular localization. The study, thus for the first time, provides an insight for the presence of highly diverge but functionally active dimeric/tetrameric TCP1 epsilon subunit in Leishmania parasite.

Sour orange (Citrus aurantium) seed, a rich source of protein isolate and hydrolysate – A thorough investigation

Sour orange (Citrus aurantium) seeds are typically discarded by juice processors as waste. This study aimed to extract protein isolates, produce hydrolysates from de-oiled sour orange seeds (SOS), and characterize their physicochemical properties. Previous studies have described methods to obtain protein isolates and hydrolysates from agricultural residues. However, there is limited data on the SOS. This research characterized protein isolates and hydrolysates from SOS, emphasizing yield, purity, and amino acid composition. Protein isolates were extracted using borate saline buffer, saline, and distilled water. Enzymatically hydrolysis was conducted using Protamex® (a commercial protease) at concentrations ranging from 0.2 to 5 g enzyme/100g protein isolate. Differential scanning calorimetry, electrophoresis, and FT-IR spectroscopy were utilized to characterize the isolates and hydrolysates. Data showed that using 5 % saline resulted in protein extraction with a yield and purity of 30 and 86 %, respectively. DSC analysis revealed that the denaturation temperature of the protein isolate was 68 °C, while the hydrolysates exhibited structural instability, as indicated by a decrease in enthalpy change compared to the isolate. The protein isolate had a 76° contact angle. The amino acid profile showed a significant presence of glutamic acid (130.530 mg/g) and arginine (70.210 mg/g). Electrophoresis analysis exhibited four major bands of the protein. The bands' intensity decreased, and new bands appeared after hydrolysis. The enzyme hydrolysis was confirmed using the O-phthaldialdehyde method and FTIR. Findings revealed that based on the free amine group quantity, the hydrolysate obtained using 5 g enzyme/100g protein isolate was 14.220 ± 0.299 μmol/mg protein. The study concluded that sour orange seeds are a good source of protein, with protein isolates and hydrolysates exhibiting desirable characteristics. More research needs to be conducted to acquire further information about their functional properties and potential applications.

A series of triphenylamine-derived fluorophores attached to a Cu-based MOF for gaseous CO optical sensing: synthesis, performance, and mechanism.

A series of triphenylamine-derived fluorescent dyes were attached to a Cu2+-containing MOF (metal-organic framework), denoted as Pm@CuMOF. The molecular structures of these dyes were discussed by the single crystal structures. Their major absorption bands peaked at 410-450 nm, showing emission bands ranging from 556 to 586 nm with emission quantum yields ranging from 8.0 to 15.1%. It was found that the [-N(C2H5)2] group generally improved sensing performance, and the -OH group in the dyes helped the Cu2+ quenching effect. Pm@CuMOF was observed by SEM as nanorods with a width of ~100 nm and a length of 300 nm. Their XRD patterns and N2 adsorption/desorption isotherms were recorded to confirm their porous structure. A low probe loading level of ~4% was determined by TGA result. The CO sensing mechanism was revealed as a Cu2+/Cu+-involved sensing mechanism based on the result of NMR titration, IR, XPS, and EPR. The fluorescence of these triphenylamine-derived dyes was firstly quenched by CuMOF. In contact with CO, Cu2+ was reduced to Cu+, accompanied by the release and fluorescence recovery of the fluorescent dyes, showing emission turn-on effect towards CO gas. Pm@CuMOF showed increased emission intensity at CO level of 0.005% (versus N2), with response times ranging from 123 s to 280 s (depending on various temperatures). Good selectivity was observed over competing alkane gases, with stable emission for at least 5 days, but no linear calibration plots were observed.