Amphipathic Phenylalanine-Induced Nucleophilic-Hydrophobic Interface Toward Highly Reversible Zn Anode

Aqueous Zn^(2+)-ion batteries(AZIBs),recognized for their high security,reliability,and cost efficiency,have garnered considerable attention.However,the prevalent issues of dendrite growth and parasitic reactions at the Zn electrode interface significantly impede their practical application.In this study,we introduced a ubiquitous biomolecule of phenylalanine(Phe)into the electrolyte as a multifunctional additive to improve the reversibility of the Zn anode.Leveraging its exceptional nucleophilic characteristics,Phe molecules tend to coordinate with Zn^(2+)ions for optimizing the solvation environment.Simultaneously,the distinctive lipophilicity of aromatic amino acids empowers Phe with a higher adsorption energy,enabling the construction of a multifunctional protective interphase.The hydrophobic benzene ring ligands act as cleaners for repelling H_(2)O molecules,while the hydrophilic hydroxyl and carboxyl groups attract Zn^(2+)ions for homogenizing Zn^(2+)flux.Moreover,the preferential reduction of Phe molecules prior to H_(2)O facilitates the in situ formation of an organic-inorganic hybrid solid electrolyte interphase,enhancing the interfacial stability of the Zn anode.Consequently,Zn||Zn cells display improved reversibility,achieving an extended cycle life of 5250 h.Additionally,Zn||LMO full cells exhibit enhanced cyclability of retaining 77.3%capacity after 300 cycles,demonstrating substantial potential in advancing the commercialization of AZIBs.

The Identification of Phenylalanine Ammonia-Lyase(PAL)Genes from Pinus yunnanensis and an Analysis of Enzyme Activity in vitro

Phenylalanine ammonia lyase(PAL)is the rate-limiting and pivotal enzyme of the general phenylpropanoid path-way,but few reports have been found on PAL genes in Pinus yunnanensis.In the present study,three PAL genes were cloned and identified from P.yunnanensis seedlings for thefirst time,namely,PyPAL-1,PyPAL-2,and PyPAL-3.Our results indicated that the open-reading frames of PyPAL genes were 2184,2157,and 2385 bp.Phylogenetic tree analysis revealed that PyPALs have high homology with other known PAL genes in other plants.In vitro enzymatic analysis showed that all three PyPAL recombinant proteins could catalyze the deamination of L-phenylalanine to form trans-cinnamic acid,but only PAL1 and PAL2 can catalyze the conversion of L-tyrosine toρ-coumaric acid.Three PyPAL genes were expressed in different tissues in 1-year-old P.yunnanensis,and such genes had different expression patterns.This study lays a foundation for further understanding of the biosynthesis of secondary metabolites in P.yunnanensis.

YCl_3-β-Phenylalanine(Phe)-H_2O体系的相化学行为

The solubilities of YCl 3 D,L β Phenyl α alanine(phe) H 2O ternary system at 25 ℃ were investigated using a semimicro phase equilibrium method and the refractive indices of the saturated solutions were determined. The results indicated that there are two new complexes formed in this system at 25 ℃, namely, Y(Phe)Cl 3·3H 2O and Y(Phe) 2Cl 3·6H 2O, both are incongreunt in water.

Polyphenol Oxidase, Peroxidase and PhenylalanineAmmonium Lyase Induced in Postharvest Peach Fruitsby Inoculation with Pichia membranefaciensor Rhizopus stolonifer

Rhizopus rot of peach fruits could be significantly suppressed by Pichia membranefaciens. Polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonium-lyase (PAL) activities induced by inoculation with P. membrane faciens or R. stolonifer were studied in postharvest peach fruits. The activities of PPO and PAL in peaches increased significantly after being inoculated with P. membrane faciens + R. stolonifer by 24 h, the activities maintained at a high level throughout the experiment. Under the condition of infected with R. stolonifer alone, activity of PPO and PAL could also increased, but the levels were lower than those treated with P. membrane faciens+ R. stolonifer. However, fruits inoculaed with P. membrane-faciens + R. stolonifer or R. stolonifer alone did not stimulated POD activity. The results suggest that the activation of these defense enzymes is involved in the action of P. membrane faciens against R. stolonifer.

Enhancement of Phenylalanine Ammonia Lyase,Polyphenoloxidase,and Peroxidase in Cucumber Seedlings by Bemisia tabaci (Gennadius) (Hemiptera:Aleyrodidae) Infestation

In this study, the activities of phenylalanine ammonia lyase （PAL）, polyphenoloxidase （PPO）, and peroxidase （POD） were assayed in cucumber seedlings （Cucumis sativus L.） at 0, 6, 12, 24, 48, 72, and 96 h after they were infested by Bemisia tabaci （Gennadius） using spectrophotometric analysis. The results indicated that herbivore infestation increased the activities of PAL, PPO, and POD. The enzymes showed different activity levels at different times after the infestation. The PAL activity reached the first high peak by 23.1% at 6 h and the highest peak by 29.1% at 48 h compared to the control. The PPO activity reached the first high peak by 22.7% at 6 h and the highest peak by 52.6% at 24 h, and the POD activity reached the highest peak by 213.2% at 6 h and another higher peak value by 135.2% at 96 h. The results suggest that the enhanced activities of the enzymes may contribute to bioprotection of cucumber plants against B. tabaci infestation.

Phenylalanine ammonia-lyase gene families in cucurbit species: Structure, evolution, and expression

Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.

EFFECTIVE INVERSION OF LEFT HEART REMODELING BY PHENYLALANINE IN ESSENTIAL HYPERTENSION

Objective The aim is to ascertain whether phenylalanine (Phe) can inverse the left heart"remodeling" in patients with essential hypertension. Methods The changes of echocardiographic variables werecompared aler 3,6 and 9 months of observation between the Phe intervention group (Phe 1g/d+amiloride complex1 tablet/d, 20 cases) and control group (placebo 1g/d+amiloride complex 1 tablet/d, 20 cases) with eitherinterventricular septum and (or) post- wall thickness≥12mm, and were carried on further to compare incross- over trial. Results (1) Phe improved elfectively the left heart and systolic dyslunction; while theimprovement, also shown in control group due to the concurrent use of diuretic antihypertensive drug-amiloridecomplex, was much less evident than that in Phe group. (2) The disturbed left heart structure and systolic functionwere improved prominently while placebo was crossed over to Phe, and the improvement decreased afer Phe wascrrossed over to placebo. (3) The changes almost attained to its peak level after 6 months and not improved furtherat 9 months. (4) The differences seen between above 2 groops could not be eoplained by their diverse drops of bloodpressure. Conclusion Phe does exert an indopendent inverse effect on cardiac "remodeling", which mightimplicate an important clinical oplication upon the prevention and control of essential hypertension and itscomplications.

Spectrofluorimetric determination of zinc（Ⅱ）with N－salicylidene phenylalanine

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Chiral Resolution of β-dl-Phenylalanine Using Chiral Macrocyclic Nickel(Ⅱ) Complexes

The reactions of chiral four-coordinated nickel（Ⅱ） complex [Ni（RR-L）]（ClO4）2/[Ni（SS- L）]（ClO4）2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni（RR-L）（β-d-HPhe）]（ClO4）2（1） and [Ni（SS-L）（β-l-HPhe）]（ClO4）2（2）, respectively（L = 5,5,7, 12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, HPhe = phenylalanine）. Single-crystal X-ray diffraction analyses revealed that the nickel（Ⅱ） atom displays a distorted octahedral coordination geometry by coordinating with four nitrogen atoms of L in a folded configuration, and two carboxylate oxygen atoms of β-d/l-HPhe in cis-position in both complexes. The monomers of [Ni（RR-L）（β-d-HPhe）]2＋ and [Ni（SS-L）（β-l-HPhe）]2＋ are connected through intermolecular hydrogen bonds to generate one-dimensional zigzag chains, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy.

Genetic diversity and population structure analysis of Pistacia species revealed by phenylalanine ammonia-lyase gene markers and implications for conservation

Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon＇s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei＇s genetic distance and genetic identity between populations revealed a close association between geographically iso- lated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among- population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species.

Synthesis, Characterization and Antibacterial Properties of Rare Earth Complexes with L-Phenylalanine and o-Phenanthroline

New solid ternary complexes of rare earth with L-Phenylalanine （ L-Phe ） and o-Phenanthroline （Phen） were synthesized in ethyl alcohol solution. Their composition were characterized by elemental analysis, molar conductance, IR, Raman, UV-VIS, TG-DTA. The compositions of the complexes were confirmed to be RE （ Phe ）3Phen Cl3 · 3H2O （ RE = La^3＋, Ce^3＋, Pr^3＋, Nd^3＋, Sm^3＋, Eu^3＋, Er^3＋, Y^3＋）. The antibacterial activities testing indicates that all these solid ternary complexes have antibacterial ability against Escherich coli, Staphy lococcus aureus, Candida albican （MIC are about 65 × 10^-4%, 15 × 10^-3%, 4 × 10^-2%, respectively）.

Modified DIX model for ion-exchange equilibrium of L-phenylalanine on a strong cation-exchange resin

L-phenylalanine,one of the nine essential amino acids for the human body,is extensively used as an ingredient in food,pharmaceutical and nutrition industries.A suitable equilibrium model is required for purification of L-phenylalanine based on ion-exchange chromatography.In this work,the equilibrium uptake of L-phenylalanine on a strong acid-cation exchanger SH11 was investigated experimentally and theoretically.A modified Donnan ion-exchange(DIX) model,which takes the activity into account,was established to predict the uptake of L-phenylalanine at various solution pH values.The model parameters including selectivity and mean activity coefficient in the resin phase are presented.The modified DIX model is in good agreement with the experimental data.The optimum operating pH value of 2.0,with the highest L-phenylalanine uptake on the resin,is predicted by the model.This basic information combined with the general mass transfer model will lay the foundation for the prediction of dynamic behavior of fixed bed separation process.

Hydrogenation of phenylpyruvic acid to phenylalanine catalyzed by Ni-B/SiO_2

Phenylalanine （Phe） is a significant amino acid that cannot be synthesized by human themselves but must be taken from environment. It was initially found that the nanosized amorphous Ni-B/SiO2 alloy prepared by the chemical reduction method was an effective catalyst for the preparation of Phe from phenylpyruvic acid （PPA） by amination and hydrogenation. It has been found that the amorphous Ni-B/SiO2 alloy catalyst exhibits superior activity and selectivity to the traditional catalysts Raney Ni and Urushibara nickel. The effects of reaction time, amounts of catalysts and ammonia solution, reaction temperature, and H2 pressure on the reaction have been investigated systematically. The results indicated that the yield of Phe was 97.9%, and the selectivity for Phe reached 98.9% when the reaction was carried out for 3 h at 333 K and 2.0 MPa of H2 with m（Cat.） ： m（PPA） = 0.6 ： 1.0 and n（NH3） ： n（PPA） = 3 ： 1. The catalysts were characterized by XRD, AAS, XPS, BET, and TEM, and the relationship between the catalyst structure and the catalytic activity was discussed in detail. It was found that the reason why Ni-B/SiO2 amorphous alloy catalyst was much more active for the preparation of Phe could be accounted for by the presence of electron-rich Ni due to electron donation from alloying B; the smaller size of Ni-B particles, the larger specific surface area of Ni-B/SiO2.

Chiral Separation of N-Benzoyl Phenylalanine Methyl Ester by Nonaqueous Capillary Electrophoresis

A successful chiral separation of N-benzoyl phenylalanine methyl ester has been achieved by nonaqueous capillary electrophoresis (NACE) using P-CD as chiral selector in formamide (FA). Some experimental parameters influencing the chiral separation such as concentration of P-CD, ionic strength and apparent pH (pH*) are discussed.

Prognostic value of ^(13)C-phenylalanine breath test on predicting survival in patients with chronic liver failure

AIM: To evaluate the prognostic value of percentage of 13C-phenylalanine oxidation (13C-PheOx) obtained by 13C-phenylalanine breath test (13C-PheBT) on the survival of patients with chronic liver failure. METHODS: The hepatic function was determined by standard liver blood tests and the percentage of 13C-PheOx in 118 chronic liver failure patients. The follow-up period was of 64 mo. Survival analysis was performed by the Kaplan-Meier method and variables that were significant (P < 0.10) in univariate analysis and subsequently introduced in a multivariate analysis according to the hazard model proposed by Cox. RESULTS: Forty-one patients died due to progressive liver failure during the follow-up period. The probability of survival at 12, 24, 36, 48 and 64 mo was 0.88, 0.78, 0.66, 0.57 and 0.19, respectively. Multivariate analysis demonstrated that Child-Pugh classes, age, creatinine and the percentage of 13C-PheOx (HR 0.338, 95% CI: 0.150-0.762, P = 0.009) were independent predictors of survival. When Child-Pugh classes were replaced by all the parameters of the score, only albumin, bilirubin, creatinine, age and the percentage of 13C-PheOx (HR 0.449, 95% CI: 0.206-0.979, P = 0.034) were found to be independent predictors of survival.CONCLUSION: Percentage of 13C-PheOx obtained by 13C-PheBT is a strong predictor of survival in patients with chronic liver disease.

Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation

The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells （chronic myeloid leukemic cells） was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data： C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = -0.15（12）, a = 5.7916（10）, b = 11.5078（19）, c = 12.924（2） A, β = 97.781（3）°, Z = 2, V = 853.4（2） A^3, De = 1.321 g/cm^3, F（000） = 356, -7≤h≤7, -10≤k≤14, -15 ≤ l≤15, R = 0.0628, wR = 0.1540 and μ（MoKa） = 0.327 mm^-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N（1）-H（1A）…O（1） makes a five-membered ring of O（1）--C（6）-C（5）--N（1）--H（1A）.

Synthesis and Crystallization of N-Benzoyl Tauryl Phenylalanine

The substrate hippuryl phenylalanine of carboxypeptidase A was selected as model to design new hapten molecule. N-Benzoyl tauryl phenylalanine (I) was synthesized and its structure was characterized by X-ray crystallography method.

Preparation of D-Phenylalanine by Asymmetric Transformation

The method of preparing D-phenylalanine by asymmetric transformation is reported. D-phenylalanine was prepared from DL-phenylalanine by two-step reaction. D-phenylalanine (2S, 3S)-tartrate was prepared by heating DL-phenylalanine, salicylaldehyde, and (2S, 3S)-tartaric acid in propionic acid; the obtained D-phenylalanine (2S, 3S)-tartrate was treated with triethylamine in ethanol giving D-phenylalanine with 98% optical purity in 69% yield.

Synthesis,Crystal Structure and Antitumor Activity of a New Zn(Ⅱ) Complex Based on N-Acetyl-L-phenylalanine and 1,10-Phenanthroline

A new Zn（Ⅱ） complex, [Zn（L）2（phen）（H2O）]（1, HL = N-acetyl-L-phenylalanine, phen = 1,10-phenanthroline） has been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction analysis. The Zn（Ⅱ） complex belongs to monoclinic, space group P21 with a = 12.6749（13）, b = 5.5965（6）, c = 22.985（2） A, β = 104.296（2）°, V = 1580.0（3） A^3, Z = 2, Mr = 676.02, Dc = 1.421 μg·m^（-3）, μ = 0.833 mm^-1, F（000） = 704, and the final R = 0.0460, wR = 0.0899 for 4422 observed reflections with I 〉 2σ（I）. The molecules form a 1D chained structure by hydrogen bonds. The antitumor activities of Zn（Ⅱ） complex against human hepatoma SMMC-7721 cells, human lung adenocarcinoma A549 cells and human colon carcinoma WiDr cells have also been investigated.

Study on parameters of L-[1-^(13)C]phenylalanine breath test for quantitative assessment of liver function in healthy subjects and patients with hepatitis B virus-related liver disease

The aims of this study are to investigate the feasibility and validity of the L-[1-13C] phenylalanine breath test (13C-PheBT) which has been used to measure hepatocyte functional capacity in hepatitis B virus-related liver disease patients and to propose validity parameters of the test in 12 healthy volunteer, 8 chronic hepatitis and 26 liver cirrhotic patients. 100mg/body nonradiative L-[1-13C] phenylalanine (13C-Phe) was administered orally to all subjects. Breath samples were taken before and different intervals within 360 min after administration. The 13CO2/12CO2 en-richment was assessed by isotope ratio mass spectrometer. The parameter percentage 13C excretion rate 13CERt (% 13C dose/h) all peaked within 10-30 min after oral 13C-Phe application. The parameters such as maximum value of 13C excretion rate,13CERmax (% 13C dose/h) (controls: 18.0±3.3; Child A: 11.0±3.8; Child B: 5.0±0.5; Child C: 3.6±1.2), 13C excretion rate at 30min, 13CER30 (% dose/h) (controls: 11. 9±2.1; Child A: 8.1±0.4; Child B: 6.1±0.9; Child C: 3.2±1.2), 13C cumulative excretion of first 60 min, 13Ccum60 (% 13C dose) (controls: 9.3±1.4; Child A: 6.6±0.7; Child B: 4.1±0.3; Child C: 2.6±0.9) and half time of 13C excretion rate, T1/2 (minutes) (controls: 40.4±4.4; chronic hepatitis: 53.4±4.4; Child A: 59.8±4.5; Child B: 102.0±17.3; Child C: 212.1±87.9) were effective indexes which could be employed to stage hepatocyte impairment and liver functional reserve of advanced HBV-related cirrhotic patients (i.e. healthy subjects, Child A, B, C); T1/2 was also useful for distinguishing mild HBV-related liver injure.