Antilisterial Activity of a Broad-Spectrum Bacteriocin,Enterocin LR/6 from <Emphasis Type="Italic">Enterococcus faecium</Emphasis> LR/6

Enterocin LR/6, a purified bacteriocin, exhibited broad inhibitory spectrum both against related as well as some food-borne pathogens such as Listeria monocytogenes, Yersinia enterocolitica, Aeromonas sp., Shigella sp., and Bacillus licheniformis. In this investigation, we have focused on L. monocytogenes as the target organism, as it is not only an important pathogen but can also survive over a wide range of environmental conditions such as refrigeration temperature, low pH, and high-salt concentration. This allows the pathogen to overcome many food preservation and safety barriers and poses a potential risk to human health. The enterocin LR/6 showed a bactericidal action against L. monocytogenes and completely inhibited the growth on agar plates, supplemented with 200 AU/ml of enterocin LR/6. The effectiveness of enterocin LR/6 in completely killing a population of acid-adapted (pH 5.2, 2 h) L. monocytogenes exposed to different temperatures (4–37 °C), pH (2.5–8.0), and osmotic (up to 30% NaCl) stress is reported here. This paper focuses on the key issue of killing of the acid-adapted L. monocytogenes cells under adverse environmental conditions.     

Expression and Characterization of the Dictyoglomus thermophilum Rt46B.1 Xylanase Gene (xynB) in Bacillus subtilis

To obtain extracellular and high-level expression of the Dictyoglomus thermophilum Rt46B.1 xylanase B gene, this gene was integrated into the α-amylase gene site of a host strain of Bacillus subtilis WB800. The extreme thermophile xylanase gene was successfully integrated and expressed in the host, measured at 24 ± 0.4 XUs/mL in the Luria broth medium supernatant. The recombinant enzyme was purified by ammonium sulfate precipitation, anion exchange chromatography, and gel filtration. The molecular mass and pI value of xylanase were estimated to be 24 kDa and 4.3, respectively. The optimal pH level and temperature of the purified enzyme were 6.5 and 85 °C, respectively. Xylanase showed reasonable activity at temperatures up to 95 °C and remained stable at 4 °C for 1 week. The purified enzyme retained most of its activity in 1 mM ethylenediaminetetraacetic acid or dithiothreitol and 0.1% Tween-20 or Triton X-100. However, strong inhibition was observed in the presence of 5 mM Mn²⁺, 0.5% sodium dodecyl sulfate, Tween-20, or Triton X-100; a strong stimulating effect was also observed in the presence of Fe²⁺. The K _m and V _max values of the recombinant xylanase for birchwood xylan were calculated to be 2.417 ± 0.36 mg/mL and 325 ± 41 μmol/min mg, respectively. Xylanase was found to be useful in the prebleaching process of paper pulps.     

Characterization of Rhamnolipid Produced by <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> Isolate Bs20

Rhamnolipid produced by Pseudomonas aeruginosa isolate Bs20 is viscous sticky oily yellowish brown liquid with a fruity odor. It showed solubility at aqueous pH > 4 with optimum solubility at pH 7–7.5 and freely soluble in ethyl acetate. This biosurfactant has a very high surface activity as it could lower the surface tension of water to 30 mN/m at about 13.4 mg/L, and it exhibited excellent stabilities at high temperatures (heating at 100°C for 1 h and autoclaving at 121°C for 10 min), salinities (up to 6% NaCl), and pH values (up to pH 13). The produced biosurfactant can be used in the crude form either as cell-free or cell-containing culture broth of the grown bacteria, since both preparations showed high emulsification indices ranged between 59% and 66% against kerosene, diesel, and motor oil. These characters make the test rhamnolipid a potential candidate for use in bioremediation of hydrocarbon-contaminated sites or in the petroleum industry. High-performance thin-layer chromatography densitometry revealed that the extracted rhamnolipid contained the two most active rhamnolipid homologues dirhamno dilipidic rhamnolipid and monorhamno dilipidic rhamnolipid at 44% and 56%, respectively, as compared to 51% and 29.5%, respectively, in a standard rhamnolipid preparation. The nature and ratio of these two rhamnolipid homologues showed to be strain dependent rather than medium-component dependent.     

Synthesis of electrospun BaSrTiO<Subscript>3</Subscript>/PVP nanofibers

Ba_1−x Sr _x TiO₃(x = 0–0.5, BST) nanofibers with diameters of 150–210 nm were prepared by using electrospun BST/polyvinylpyrrolidone (PVP) composite fibers by calcination for 2 h at temperatures in the range of 650–800 °C in air. The morphology and crystal structure of calcined BST/PVP nanofibers were characterized as functions of calcination temperature and Sr content with an aid of XRD, FT-IR, and TEM. Although several unknown XRD peaks were detected when the fibers were calcined at temperatures less than 750 °C, they disappeared with increasing the temperature (above 750 °C) due to its thermal decomposition and complete reaction in the formation of BST. In addition, the FT-IR studies of BST/PVP fibers revealed that the intensities of the O–H stretching vibration bands (at 3430 and 1425 cm⁻¹) became weaker with increasing the calcination temperature and a broad band at 540 cm⁻¹, Ti–O vibration, appeared sharper and narrower after calcination above 750 °C due to the formation of metal oxide bonds. However, no effect of Sr content on the crystal structure of the composites was detected.     

Purification and Characterization of Thermostable Chitinase from <Emphasis Type="Italic">Bacillus licheniformis</Emphasis> SK-1

Chitinase was purified from the culture medium of Bacillus licheniformis SK-1 by colloidal chitin affinity adsorption followed by diethylamino ethanol-cellulose column chromatography. The purified enzyme showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular size and pI of chitinase 72 (Chi72) were 72 kDa and 4.62 (Chi72) kDa, respectively. The purified chitinase revealed two activity optima at pH 6 and 8 when colloidal chitin was used as substrate. The enzyme exhibited activity in broad temperature range, from 40 to 70°C, with optimum at 55°C. It was stable for 2 h at temperatures below 60°C and stable over a broad pH range of 4.0–9.0 for 24 h. The apparent K _m and V _max of Chi72 for colloidal chitin were 0.23 mg ml⁻¹ and 7.03 U/mg, respectively. The chitinase activity was high on colloidal chitin, regenerated chitin, partially N-acetylated chitin, and chitosan. N-bromosuccinamide completely inhibited the enzyme activity. This enzyme should be a good candidate for applications in the recycling of chitin waste.     

The highly crosslinked dimethacrylic/divinylbenzene copolymers

The thermal stability of the ionic liquids (ILs) 1-n-butyl-3-methylimidazolium bromide, [BMIM]Br, and 1-n-octyl-3-methylimidazolium bromide, [OMIM]Br, was evaluated through thermogravimetry (TG). Long-term isothermal TG studies revealed that both of these ILs exhibit appreciable decomposition even at temperatures significantly lower than the onset decomposition temperature, previously determined from fast scan TG experiments. The long-term TG studies of both the ILs showed linear mass loss as a function of time at each temperature of 10 °C interval in the range 533–573 K over a period of 10 h. The kinetics of isothermal decomposition of ILs was analyzed using pseudo-zero-order rate expression. The activation energies for the isothermal decomposition of [BMIM]Br and [OMIM]Br under nitrogen atmosphere are 219.86 and 212.50 kJ mol⁻¹, respectively. The moisture absorption kinetics of these ILs at 25 °C and 30% relative humidity (RH) and at 85 °C and 85% RH were also studied. Water uptake of ILs exposed at 25 °C/30%RH follows a simple saturation behavior in agreement with Weibull model while that at 85 °C/85%RH fortuitously fit into the Henderson–Pabis model.     

Characterization of Smallest Active Monomeric Lipase from Novel <Emphasis Type="Italic">Rhizopus</Emphasis> Strain: Application in Transesterification

An extracellular lipase-producing fungus was isolated from oil-rich soil. This fungus belongs to the genus Rhizopus and clades with Rhizopus oryzae. Lipase was purified to homogeneity from this novel fungal source using ammonium sulphate precipitation followed by Q-Sepharose chromatography. The extracellular lipase was purified 8.6–fold, and enzymatic properties were studied. The molecular mass of the purified enzyme was estimated to be 17 kD by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and 16.25 kD by matrix-assisted laser desorption ionization/time-of-flight analysis. The native molecular mass was estimated to be 17.5 kD by gel filtration, indicating the protein to be monomer. The optimum pH and temperature for the enzyme catalysis were 7.0 °C and 40 °C, respectively. Enzyme was stable in pH range 6.0–7.0 and retains 95–100% activity when incubated at 50 °C for 1 h. The pI of the purified lipase was 4.2. Enzyme was stable in the organic solvents such as ethanol, hexane and methanol for 2 h. Purified enzyme was used for transesterification of oleic acid in the presence of ethanol for production of oleic acid ethyl ester with a conversion efficiency of 66% after 24 h at 30 °C.     

Antifungal and Antiproliferative Activities of Lectin from the Rhizomes of Curcuma amarissima Roscoe

A lectin was purified from the rhizomes of Curcuma amarissima Roscoe by aqueous extraction, fractionation with 80% saturated ammonium sulfate, and a combination of affinity and gel chromatography on ConA Sepharose and Superdex G-75, respectively. The molecular mass of the purified lectin was 32.4 kDa, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The lectin showed no significant specificity in its ability to hemagglutinate erythrocytes from human blood groups (A, B, AB, and O), but for other animals, it only agglutinated rabbit and rat, and not mouse, guinea pig, goose, and sheep erythrocytes. The lectin was stable at temperatures below 40°C, but the hemagglutinating activity halved when it was heated to 45–85°C and was completely lost at 95°C. The hemagglutinating activity was more stable at 80°C than at 70°C and was rapidly inactivated at 90°C. It showed a maximum hemagglutination activity within the pH range of 8.0–11.0. The deduced amino acid sequence of an internal tryptic peptide sequence of this purified lectin showed sequence similarity (homology) to other members of the leucoagglutinating phytohemagglutinin precursor family, whilst the complete lectin inhibited the in vitro growth of three plant pathogenic fungi, Fusarium oxysporum, Exserohilum turicicum, and Colectrotrichum cassiicola, at a concentration of 17.5 to 35 μg, and showed in vitro cytotoxicity against the BT474 breast cancer cell line with an IC₅₀ of approximately 21.2 μg.     

Purification and Properties of a Psychrotrophic <Emphasis Type="Italic">Trichoderma</Emphasis> sp. Xylanase and its Gene Sequence

A psychrotrophic fungus identified as Trichoderma sp. SC9 produced 36.7 U/ml of xylanase when grown on a medium containing corncob xylan at 20 °C for 6 days. The xylanase was purified 37-fold with a recovery yield of 8.2%. The purified xylanase appeared as a single protein band on SDS-PAGE with a molecular mass of approximately 20.5 kDa. The enzyme had an optimal pH of 6.0, and was stable over pH 3.5–9.0. The optimal temperature of the xylanase was 42.5 °C and it was stable up to 35 °C at pH 6.0 for 30 min. The xylanase was thermolabile with a half-life of 23.9 min at 45 °C. The apparent K _m values of the xylanase for birchwood, beechwood, and oat-spelt xylans were found to be 3, 2.1, and 16 mg/ml respectively. The xylanase hydrolyzed beechwood xylan and birchwood xylan to yield mainly xylobiose as end products. The enzyme-hydrolysed xylotriose, xylotetraose, and xylopentose to produce xylobiose, but it hardly hydrolysed xylobiose. A xylanase gene (xynA) with an open reading frame of 669 nucleotide base pairs (bp), encoding 222 amino acids, from the strain was cloned and sequenced. The deduced amino acid sequence of XynA showed 85% homology with Xyn2 from a mesophilic strain of Trichoderma viride.     

Sugar Ester Synthesis by Thermostable Lipase from <Emphasis Type="Italic">Streptomyces thermocarboxydus</Emphasis> ME168

The extracellular lipase from Streptomyces thermocarboxydus ME168 was purified to 9.5-fold with 20% yield, following concentration by acetone precipitation, ion exchange chromatography (Resource Q) and gel filtration chromatography (Superdex 200), respectively. The purified enzyme had an apparent molecular mass of 21 kDa by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The N-terminal sequence of the lipase was ASDFDDQILG and was different from most other reported lipase. The enzyme showed maximum activity at 50 °C with the half-life of 180 min at 65 °C. It showed high stability at a broad pH range of 5.5–9.5 and was thermostable at the temperature range of 25–60 °C. The K _m and V _max were 0.28 mM and 1,428 U/mg, respectively, using p-nitrophenyl palmitate as substrate. It was active toward p-nitrophenyl ester with medium to long acyl chain (C₈–C₁₆). Lipase activity was inhibited by Zn²⁺, dithiothreitol (DTT), EDTA and some organic solvents, e.g., ethanol, acetone, dioxane, acetronitrile, tert-butanol and pyridine. Immobilized crude lipase of S. thermocarboxydus ME168 on celite could be used to synthesize sugar esters from glucose and vinyl acetate, vinyl butyrate or vinyl caproate in tert-butanol:pyridine (55:45 v/v) at 45 °C with conversion yields of 93, 67 and 55%, respectively.     

Purification and Biochemical Characterization of a Highly Thermostable Xylanase from <Emphasis Type="Italic">Actinomadura</Emphasis> sp. Strain Cpt20 Isolated from Poultry Compost

An extracellular thermostable xylanase from a newly isolated thermophilic Actinomadura sp. strain Cpt20 was purified and characterized. Based on matrix-assisted laser desorption–ionization time-of-flight mass spectrometry analysis, the purified enzyme is a monomer with a molecular mass of 20,110.13 Da. The 19 residue N-terminal sequence of the enzyme showed 84% homology with those of actinomycete endoxylanases. The optimum pH and temperature values for xylanase activity were pH 10 and 80 °C, respectively. This xylanase was stable within a pH range of 5–10 and up to a temperature of 90 °C. It showed high thermostability at 60 °C for 5 days and half-life times at 90 °C and 100 °C were 2 and 1 h, respectively. The xylanase was specific for xylans, showing higher specific activity on soluble oat-spelt xylan followed by beechwood xylan. This enzyme obeyed the Michaelis–Menten kinetics, with the K _m and k _cat values being 1.55 mg soluble oat-spelt xylan/ml and 388 min⁻¹, respectively. While the xylanase from Actinomadura sp. Cpt20 was activated by Mn²⁺, Ca²⁺, and Cu²⁺, it was, strongly inhibited by Hg²⁺, Zn²⁺, and Ba²⁺. These properties make this enzyme a potential candidate for future use in biotechnological applications particularly in the pulp and paper industry.     

Fibrinolytic Serine Protease Isolation from <Emphasis Type="Italic">Bacillus amyloliquefaciens</Emphasis> An6 Grown on <Emphasis Type="Italic">Mirabilis jalapa</Emphasis> Tuber Powders

In this study, Mirabilis jalapa tuber powder (MJTP) was used as a new complex organic substrate for the growth and production of fibrinolytic enzymes by a newly isolated Bacillus amyloliquefaciens An6. Maximum protease activity (1,057 U/ml) with casein as a substrate was obtained when the strain was grown in medium containing (grams per liter) MJTP 30, yeast extract 6, CaCl₂ 1, K₂HPO₄ 0.1, and K₂HPO₄ 0.1. The strain was also found to grow and produce extracellular proteases in a medium containing only MJTP, indicating that it can obtain its carbon, nitrogen, and salts requirements directly from MJTP. The B. amyloliquefaciens An6 fibrinase (BAF1) was partially purified, and fibrinolytic activity was assayed in a test tube with an artificial fibrin clot. The molecular weight of the partially purified BAF1 fibrinolytic protease was estimated to be 30 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration. The optimum temperature and pH for the caseinolytic activity were 60 °C and 9.0, respectively. The enzyme was highly stable from pH 6.0 to 11.0 and retained 62% of its initial activity after 1 h incubation at 50 °C. However, the enzyme was inactivated at higher temperatures. The activity of the enzyme was totally lost in the presence of phenylmethylsulfonyl fluoride, suggesting that BAF1 is a serine protease.     

Production and Characterization of Cellobiohydrolase from a Novel Strain of <Emphasis Type="Italic">Penicillium purpurogenum</Emphasis> KJS506

A high cellobiohydrolase (CBH)-producing strain was isolated and identified as Penicillium purpurogenum KJS506 according to the morphology and comparison of internal transcribed spacer rDNA gene sequence. When rice straw and corn steep powder were used as carbon and nitrogen sources, respectively, a maximum CBH activity of 2.6 U mg-protein⁻¹, one of the highest among CBH-producing microorganisms, was obtained. The optimum temperature and pH for CBH production were 30 °C and 4.0, respectively. The increased production of CBH in P. purpurogenum culture at 30 °C was confirmed by two-dimensional electrophoresis followed by MS/MS sequencing of the partial peptide. The internal amino acid sequences of P. purpurogenum CBH showed a significant homology with hydrolases from glycoside hydrolase family 7. The extracellular CBH was purified to homogeneity by sequential chromatography of P. purpurogenum culture supernatants on a DEAE-sepharose column, a gel filtration column, and then on a Mono Q column with fast-protein liquid chromatography. The purified CBH was a monomeric protein with a molecular weight of 60 kDa and showed broad substrate specificity with maximum activity towards p-nitrophenyl β-d-cellobiopyranoside. P. purpurogenum CBH showed t _1/2 value of 4 h at 60 °C and V _max value of 11.9 μmol min⁻¹ mg-protein⁻¹ for p-nitrophenyl-d-cellobiopyranoside. Although CBHs have been reported, the high specific activity distinguishes P. purpurogenum CBH.     

Synthesis and colour properties of pigments based on terbium-dopped Mg<Subscript>2</Subscript>SnO<Subscript>4</Subscript>

The main aim of this work was to synthesize the magnesium orthostannate doped by terbium cations and tested whether these materials can be used for colouring of the different materials, e.g. organic binder and ceramic glazes. Initial composition of pigments was counted according the general formula 2MgO(1 − x)SnO₂–xTbO₂, where values of x varied from 0.1 to 0.5 in 0.1 steps. The simultaneous TG/DTA measurements of mixture containing tin oxide, magnesium carbonate hydroxide and terbium oxide showed that the formation of a new compound started at temperature 1,029 °C, but single-phase system was not prepared. Granulometric compositions of samples that were prepared by calcining at temperatures 1,300–1,400 °C are characterized by values of median (d ₅₀) in range 4–8 μm. The calcining temperature 1,500 °C caused the increase of the particle sizes at around 12 μm. The composition of sample 2MgO–1.5SnO₂–0.5TbO₂ and heating temperature 1,500 °C are the most suitable conditions for preparation of colourfully interesting pigment that can be recommended also for colouring of ceramic glazes. Especially, for colouring of decorative lead containing glaze G 07091 containing 5 wt% of PbO and 8 wt% of Al₂O₃.     

Purification and Characterization of Pectin Lyase Produced by Aspergillus terricola and its Application in Retting of Natural Fibers

An indigenously isolated fungal strain identified as Aspergillus terricola with assigned fungal strain number MTCC 7588 has been used as source for pectin lyase production. The extracellular pectin lyase was purified to homogeneity from the culture filtrate of A. terricola by ion exchange and gel filtration chromatography. The determined molecular weight was 35 ± 01 kDa. The K _m and k _cat (turnover) values of the purified enzyme at 37 °C using citrus pectin as the substrate were found to be 1.0 mg/ml and 110.0 s⁻¹, respectively. The pH and temperature optima of the enzyme were 8.0 and 50 °C, respectively. The retting ability of the purified pectin lyase for natural fibers viz. Cannabis sativa and Linum usitatissimum has been demonstrated for the first time.     

Fast responsive poly(<Emphasis Type="Italic">N,N</Emphasis>-diethylacrylamide) hydrogels with interconnected microspheres and bi-continuous structures

We prepared thermo-responsive polymer hydrogels by γ-ray irradiation of aqueous solutions of N, N-diethylacrylamide at different temperatures below and above its lower critical solution temperature (LCST). Poly(N, N-diethylacrylamide) gel had a transparent and homogeneous structure when the radiation-induced polymerization and crosslinking were carried out below the LCST (25 °C) of the polymer. On the other hand, cloudy and heterogeneous gels were formed at temperatures above the LCST of the polymer (>35 °C). From environmental scanning electron microscopy observations, the gels prepared at 35 and 40 °C were seen to show sponge-like bi-continuous porous structures, while those prepared at 50 °C showed a porous structure consisting of interconnected microspheres. For temperature changes between 10 and 40 °C, gels with porous structures showed rapid volume transitions on a time scale of about a minute, not only for shrinking but also for swelling processes, which is in remarkable contrast to the porous poly(N-isopropylacrylamide) hydrogels.     

A new charging mode of Li-ion batteries with LiFePO<Subscript>4</Subscript>/C composites under low temperature

Li-ion batteries with LiFePO₄/C composites are difficult to be charged at low temperatures. In order to improve the low temperature performance of LiFePO₄/C power batteries, the charge–discharge characteristics were studied at different temperatures, and a new charging mode under low temperature was proposed. In the new charging mode, the batteries were excited by current pulses with the charge rates between 0.75 C and 2 C, while the discharge rates between 3 and 4 C before the conventional charging (CC–CV). Results showed that the surface temperature of Li-ion battery ascended to 3 °C at the end of pulse cycling when the environment temperature was −10 °C. Comparing with the conventional charging, the whole charge time was cut by 36 min (23.4%) and the capacity was 7.1% more at the same discharge rate, respectively.     

Development of a UHPLC-MS/MS method for the measurement of chlortetracycline degradation in swine manure

An ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed capable of simultaneously measuring chlortetracycline (CTC), epi-chlortetracycline, and isochlortetracycline (ICTC), as well as other structurally related tetracyclines in swine manure. A simple sample preparation was used consisting of extraction, dilution, centrifugation, and ultrafiltration. The concentrations of analyte were calculated using d₆-tetracycline as an internal standard in the matrix-matched standard curve. A solvent gradient resolved the compounds in 3.5 min with an additional 1.5 min of re-equilibration allowing the analyses of a large number of samples in a short period of time. MS/MS was used as the detection method giving analyte confirmation in addition to a large dynamic range and low detection limit. The UHPLC-MS/MS method successfully resolved multiple degradation products of CTC from the complex manure matrix. The method detection limits ranged from 1.9 pg/μL for CTC to 7.3 pg/μL for ICTC, and the calibration curve was linear from 1 to 10,000 pg/μL. The method was tested by measuring CTC and its degradation products as a function of time in incurred swine manure that had been incubated at three different temperatures (22 °C, 38 °C, and 55 °C). CTC concentration at 22 °C decreased 44% after 25 days; greater percentage decreases were observed when the manure was stored at elevated temperatures (96% and 98% for 38 °C and 55 °C, respectively). The concentration of the microbiologically inactivate isomer, ICTC, increased over the incubation period. At 22 °C, ICTC continued to increase through 25 days of incubation; at 38 °C, ICTC concentration plateaued on day 14 while at 55 °C ICTC concentration plateaued on day 7, with concentration increases of 198%, 374%, and 282% for 22 °C, 38 °C, and 55 °C, respectively.     

Production and Stability of Protease from <Emphasis Type="Italic">Candida buinensis</Emphasis>

Cow raw milk from dairy cooperatives was examined for its microbial composition. Among the isolates identified, 17.6% were yeasts. The most frequent genus was Candida, although members belonging to the genera Brettanomyces, Dekkera, and Geotricum were also identified. Although qualitative and quantitative tests for extracellular proteolytic activity were positive for all the species isolated, Candida buinensis showed the highest response (23.5 U/mg); therefore, it was selected for subsequent investigation. The results of fermentations carried out at variable temperature, pH, and soybean flour concentration, according to a 2³ full factorial design, demonstrated that this yeast ensured the highest production of extracellular proteases (573 U/mL) when cultivated at 35 °C, pH 6.5, and using soybean flour concentrations in the range 0.1–0.5% (w/v). The cell-free supernatants showed the highest activity at 25 °C and pH 7.0, and satisfactory stability in the ranges 25–30 °C and pH 7–9. The first-order rate constants of protease inactivation in the cell-free supernatants were calculated at different temperatures from semi-log plots of the residual activity versus time and then used in Arrhenius and Eyring plots to estimate the main thermodynamic parameters of thermoinactivation (E* = 40.0 kJ/mol; ΔH* = 37.3 kJ/mol; ΔS* = −197.5 J/mol K; ΔG* = 101 kJ/mol).