High-resolution and high-sensitivity absorption spectroscopy in external optical resonators with fast frequency tuning.

The effect of the laser frequency tuning rate on a weak optical absorption line profile ~(10-5-10-7) cm-1 under conditions when the molecules were in a high-quality optical resonator was studied. The authors used a diode laser and an analytical cavity with two pairs of mirrors with reflectivity of 99% and 99.98% in the ~1.4 µm region. Water vapor at reduced pressure (0.03-1) Torr served as an absorbing medium. A high spectral resolution was obtained by directing laser radiation into the cavity with a small offset relative to its axis (off-axis ICOS). The frequency tuning rate was varied within (102-103) cm-1 s-1. With the increase of the rate, a shift and asymmetry of the Doppler absorption profile were observed. When the tuning direction was changed and the rate was kept the same, the effect preserved in time and mirrored symmetrically on the frequency scale. The measurements were consistent with calculations that took into account the finite lifetime of photons in the cavity and the real ratio of the effective optical path to the coherence length of the laser radiation. Limitations on the frequency tuning rate were discussed using quantitative absorption spectroscopy methods for measuring molecule concentrations.

Biocatalytic conversion of poultry processing leftovers: Optimization of hydrolytic conditions and peptide hydrolysate characterization.

Peptide hydrolysate (PH) was produced by deep controllable bioconversion of poultry processing leftovers (broiler necks), by means of a multienzyme composition, containing four commercially available enzyme preparations (Alcalase, Neutrase, Flavourzyme, Protamex). The design of multienzyme composition (MEC) was applied to yield a hydrolysate with adjusted properties, including minimized antigenicity and bitterness. The protein recovery was optimized using Box-Behnken response surface design. The individual and interactive effects of hydrolysis conditions (time, hydromodule and MEC dosage) were studied. The experimental data were analyzed by ANOVA method and a well-predictive, second order polynomial model was developed using multiple regression analysis. Optimal hydrolysis conditions were found to be: hydrolysis time 3 h, hydromodule 2.25 l/kg and dosage of MEC 0.25%. The corresponding predicted value for protein recovery was 75.34%, 2 times higher compared to traditional long-term heating hydrolysis. The PH obtained is a low allergenic product with high antioxidant capacity.

[Reactivating factor of Luteococcus japonicus subsp. casei: isolation and characterization].

It has been shown that a producer strain of reactivating factor (RF) is identical to a typical strain of Luteococcus japonicus DSM 10546 from the Propionibacteriaceae family according to the physiological and biochemical properties and the sequencing of 16S rRNA fragments. A number of phenotypical differences from the model strain allowed the producer strain to be considered a subspecies of Luteococcus japonicus, and it was named Luteococcus japonicus subsp. casei. At cultivation of the producer, RF is secreted into the medium and plays the role of a signaling molecule. RF antioxidant activities towards various organic radicals may be a possible mechanism of its protective and reactivating effects. Metabolites secreted by the L. casei producer strain into the culture medium were separated by a combination of liquid chromatographies. Four components possessing biological activities were found. The most active one was studied by MALDI-TOF mass spectrometry, which revealed that it is a polypeptide. Primary identification of some amino acid residues was performed. Sugar residues were found in the structure.

[Results of measuring neutrons doses and energy spectra inside Russian segment of the International Space Station in experiment "Matryoshka-R" using bubble detectors during the ISS-24-34 missions].

The paper presents the results of calculating the equivalent dose from and energy spectrum of neutrons in the right-hand crewquarters in module Zvezda of the ISS Russian segment. Dose measurements were made in the period between July, 2010 and November, 2012 (ISS Missions 24-34) by research equipment including the bubble dosimeter as part of experiment "Matryoshka-R". Neutron energy spectra in the crewquarters are in good agreement with what has been calculated for the ISS USOS and, earlier, for the MIR orbital station. The neutron dose rate has been found to amount to 196 +/- 23 microSv/d on Zvezda panel-443 (crewquarters) and 179 +/- 16 microSv/d on the "Shielding shutter" surface in the crewquarters.

[Analysis of functional properties of biologically active substances using eukaryotic cell models (review)].

This work presents an analysis of current data on the investigation into the functional properties of biologically active substances in model systems based on cultivated human cells. The knowledge regarding the practical application of cell cultures for the analysis of functional properties of bioactive substances is summarized, including antioxidant, immunomodulating, pro- and prebiotics, and chemoprevention properties. The most promising directions in cell culture model development for the investigation of functional properties, including three-dimensional models, are discussed.

[Comparisons of cerebral circulation parameters in schoolchildren living in the Far East and European North].

Transcranial Doppler sonography and impedansometry was used to study cerebral circulation in students aged from 7 to 17 living in the North in the "absolute discomfort" area (Magadan region. 62 degrees North, 158 degrees East, n = 167) and "discomfort" area (Arkhangelsk region, 61 degrees North, 41 degrees East, n = 52). New data were obtained about both blood flow parameters in main cerebral arteries, vessels tone and vasomotor reactivity as well as differences between these indices in children from the two northern areas. The results reveal that arterial blood flow velocity (BFV) in cerebral arteries is faster in Koryaks and Evens who are the children of the native population compared to BFV in the children born in the North whose parents represent newcomers. A tendency exists in the form of vascular tone rising in the living in the North students. This tendency is more expressed in children and adolescents from Magadan region which is distinguished from Arkhangelsk region by more severe climate. The indices that characterize individual alterations of cerebral circulation under hypoxic-cold factors as well as population peculiarities related to "polar adaptive type of metabolism" forming are discussed.

[Enzymatic hydrolysis of keratin-containing stock for obtaining protein hydrolysates].

Optimization of the process of enzymatic hydrolysis of keratin-containing stock aimed at obtaining hydrolysates of high biological value has been performed. The increasing of the stock/water weight ratio, the amount of the alkaline protease preparation from Acremonium chrysogenium added and the temperature of the reaction mixture resulted in an increase in the yield and antioxidant capacity of hydrolysis products. The molecular masses of soluble products obtained under optimal hydrolysis conditions ranged from 3.55 to 3.60 kDa. High antioxidant capacity, 100% bioavailability and a well-balanced amino acid composition was characteristic of the hydrolysis products.

[Antioxidant and peroxidase activity of saliva in patients with inflammatory periodontal diseases and ability of their correction].

Comparative investigation of antioxidant and peroxidase activities of mixtured saliva during testing loads in control group, as well as in patients with caries and combination of caries with inflammatory periodontal diseases was carried out. Antioxidant activity of saliva in the last two groups was significantly lower, so their correction with xidiphone was made.

[Application of xidiphone in complex of measures for inflammatory periodontal disease prevention].

Investigation of basic biochemical parameters of mixed saliva during sugar and urea tests including application of xidiphone has been carried out. Following parameters--pH, concentration of calcium, inorganic phosphate and fluoride--were measured. It was shown that xidiphone was an universal regulator of acid-base state, calcium-phosphorus an calcium-fluoride homeostasis in oral cavity.

Diode ring-down spectroscopy without intensity modulation in an off-axis multipass cavity.

Cavity ring-down spectroscopy with an off-axis multipass cell and space separated detectors is proposed to record absorption spectra without modulation of the diode laser intensity. The spectral resolution is approximately 0.0003 cm-1. The whole spectrum is obtained for one continuous tuning of the laser frequency for approximately 20 ms. When comparing this method to conventional CRDS the required rise time is 1000 times slower. The recording of the whole spectrum for one measurement gives additional possibilities of signal extraction at relatively high noise. The technique is applied to absorption measurement of NO2 in atmosphere.

Integrative and replicative transformation of Penicillium canescens with a heterologous nitrate-reductase gene.

A wild isolate of Penicillium canescens was subjected to mutagenesis, and 150 chlorate-resistant mutants were isolated and classified in respect of their ability to utilize various nitrogen sources. Strains supposedly deficient in nitrate reductase have been transformed with the nitrate-reductase gene from Aspergillus niger. Transformation probably occurred by non-homologous integration of the transforming vector into the chromosome. Co-transformation with the AMA 1 replicating element from A. nidulans enhanced transformation frequency up to 2000-fold, and was shown to result in autonomous maintenance of replicating concatenates, one of which was re-isolated by transformation of E. coli.

[Molecular cloning of the gene for secreted beta-galactosidase of the filamentous fungus Penicillium canescens]. / Molekuliarnoe klonirovanie gena sekretiruemoi beta-galaktozidazy mitselial'nogo griba Penicillium canescens.

A secreted beta-galactosidase gene from P. canescens was cloned using synthetic oligonucleotide probes and its nucleotide sequence was partially determined. The gene was shown to be present in the genome as a single copy. The deduced primary structure of the signal peptide and the first 25 amino acid residues of the mature protein was established. The structure analysis of the beta-galactosidase gene revealed at least one short intron 64 bp long. The transcription start point was found to be located 89 bp upstream the initiation codon. Some peculiarities of the signal peptide cleavage mechanism are discussed.

[Molecular characteristics of beta-galactosidase secreted by Penicillium canescens]. / Molekuliarnye kharakteristiki sekretiruemoi beta-galaktozidzay Penicillium canescans.

Extracellular beta-galactosidase from P. canescens culture medium was purified by ion-exchange chromatography on DEAE and CM-Sepharose CL-6B and gel filtration. The enzyme active form was shown to be a monomer with a molecular weight of about 120 kDa; the isoelectric point is 6.7 and the sedimentation coefficient is 6.5. In terms of physico-chemical and catalytic properties, the purified enzyme is similar to beta-galactosidases of other fungi of genus Penicillium. The amino acid composition and the NH2-terminal sequence of 24 residues non-homologous to the corresponding sequences of bacterial and yeast beta-galactosidases were determined.

Soybean 11S globulin polypeptides have an antigenic homology with 11S globulins from various plants.

Rabbit serum antibodies (AB) against glycinin acidic polypeptides were separated by cross exhausting, and the antibody fractions for each of the two subfamilies of glycinin subunits (A1 and A3) were obtained. The antibodies were used in the immuno blot assay with seed protein of various plant classes. Polypeptides homologous to soybean glycinin were detected. Homology with A1 polypeptide was revealed in more cases than with A3. Total seed protein preparations were subjected to centrifugation in sucrose density gradient, and the polypeptides, imunochemically related to glycinin, occurred only in fractions with sedimentation constant about 11S. The nativity of conservative antigenic determinants of 11S globulins is discussed.