scholarly journals Hot Resistance of Spores from the Thermophilic Bacillus horneckiae SBP3 of Shallow Hydrothermal Vent Origin Elucidated by Spectroscopic Analyses

2021 ◽  
Vol 11 (9) ◽  
pp. 4256
Author(s):  
Vincenzo Zammuto ◽  
Maria Teresa Caccamo ◽  
Salvatore Magazù ◽  
Antonio Spanò ◽  
Salvatore Guglielmino ◽  
...  
Keyword(s):  
Hydrothermal Vent ◽  
Saturated Fatty Acids ◽  
Protein Structures ◽  
Ftir Analysis ◽  
Basic Information ◽  
Thermophilic Bacillus ◽  
Spectroscopic Analyses ◽  
Heat Treated ◽  
Wet Heat ◽  
Spore Proteins

Spores from Bacillus horneckiae SBP3 (SBP3) of shallow hydrothermal vent origin have recently been reported to survive extreme conditions more often than their close phylogenetic relatives B. horneckiae DSM 23495T (BHO) and B. subtilis 168 (BSU) used in biodosimetry and the space microbiology model. To investigate the structures of unheated spores, Fourier-transform infrared spectroscopy (FTIR) analysis was used. The FTIR spectra of the spores from the strains SBP3, BHO and BSU mainly differed in the region that referred to lipids and amino acids or polypeptides, indicating that the SBP3 spores were richer in saturated fatty acids, and the protein structures of SBP3 and BHO spores were more aggregated and complex than those of BSU. SBP3 spores were more resistant (LD90 = 4.2 ± 0.3 min) to wet heat treatment (98 °C) than BHO (LD90 = 1.8 ± 0.2 min) and BSU (LD90 = 2.9 ± 0.5 min) spores were. In comparison to the untreated spores, the Raman spectra of the wet-heat-treated SBP3 spores showed minor variations in the bands that referred to proteins, whereas major changes were observed in the bands that referred to lipids and amide I in the heated BSU spores and to both lipids and proteins bands in the treated BHO spores. These results suggest that the major stability of SBP3 spore proteins could explain their greater resistance to wet heat compared to BHO and BSU. Our findings provide basic information for further comparative studies into spore responses to natural and laboratory stresses, which are useful in several different fields, such as astrobiology.

XRD and FTIR analysis heat treated lithium bismo-borate glasses doped with 1.0 mol% copper ferrite

2018 ◽  
Author(s):  
Arti Yadav ◽  
P. Narwal ◽  
Manjeet S. Dahiya ◽  
T. Dahiya ◽  
A. Agarwal ◽  
...  
Keyword(s):  
Copper Ferrite ◽  
Borate Glasses ◽  
Ftir Analysis ◽  
Heat Treated

Effect of Heat Treatment on the Combustion Characteristics of a Lignite

2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Zhezi Zhang ◽  
Mingming Zhu ◽  
Jianbo Li ◽  
Kai Zhang ◽  
Guoqing Shen ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Ignition Delay ◽  
Delay Time ◽  
Heat Treatment Temperature ◽  
Ignition Delay Time ◽  
Treatment Temperature ◽  
Ftir Analysis ◽  
Single Particles ◽  
Heat Treated ◽  
Ignition And Combustion

In this study, the ignition and combustion behavior of raw and heat-treated single particles of lignite were experimentally investigated, with a focus on the effect of heat treatment temperatures. The lignite particles were heat treated to various final temperatures (473, 623 and 773 K) in nitrogen and characterized using proximate, ultimate, and Fourier transform infrared spectroscopy (FTIR) analysis. A single lignite particle of 2 or 3 mm in diameter was suspended on a silicon carbide fiber and burned in air in a horizontal tube furnace operating at 1123 K. The ignition and combustion process of the particle was record using a color CCD camera at 25 fps. The ignition mechanism, ignition delay time, volatile flame duration, and burnout time of the single particles were examined by processing the recorded images. The proximate and ultimate analysis results indicated that the volatile matter and oxygen contents decreased, while the carbon content increased with increasing temperature of heat treatment. This trend was consistent with observations in the FTIR analysis, in which the intensity of oxygen-containing functional groups decreased with increasing the heat treatment temperature. The ignition of raw and heat treated lignite particles followed a joint hetero-homogeneous mechanism under all conditions studied. The ignition delay time, volatile flame extinction time, and the total combustion time decreased with increasing heat treatment temperature up to 623 K. A further increase in the heat treatment temperature to 773 K resulted in prolonged key ignition and combustion characteristic times.

Highly Porous Hydroxyapatite Ceramics for Engineering Applicatios

2010 ◽  
Vol 63 ◽  
pp. 408-413 ◽  
Author(s):  
Hrvoje Ivankovic ◽  
Sebastijan Orlic ◽  
Dajana Kranzelic ◽  
Emilija Tkalcec
Keyword(s):  
Average Length ◽  
Average Diameter ◽  
Ftir Analysis ◽  
X Ray Diffraction ◽  
Gas Cell ◽  
Porous Hydroxyapatite ◽  
Hydroxyapatite Ceramics ◽  
Heat Treated ◽  
Hydrothermal Transformation ◽  
Highly Porous

Highly porous hydroxyapatite (Ca10(PO4)6(OH)2, HA) was prepared through hydrothermal (HT) transformation of aragonitic cuttlefish bones (Seppia Officinalis L. Adriatic Sea) in the temperature range from 140°C to 220°C for 20 minutes to 48 hours. Mechanism of hydrothermal transformation of bones was investigated by DTA/TG analyzer coupled online with FTIR spectrometric gas cell equipment (DTA-TG-EGA-FTIR analysis), X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). DTA-TG-EGA-FTIR analysis have shown the release of CO2 at about 400°C, 680°C and 990°C. The first release could be attributed to organics not completely removed from the heat treated bones, and the second release to decomposition of unconverted aragonite, whereas, the third one could be attributed to CO3 2– groups incorporated in the structure of HA. The interconnecting porous morphology of the starting material (aragonite) was maintained during the HT treatment. The formation of dandelion-like HA spheres with diameter from 3 to 8 μm were observed, which further transformed into nanoplates and nanorods with an average diameter of about 200-300 nm and an average length of about 8-10 μm.

scholarly journals Kinetics of Germination of Wet-Heat-Treated Individual Spores of Bacillus Species, Monitored by Raman Spectroscopy and Differential Interference Contrast Microscopy

2011 ◽  
Vol 77 (10) ◽  
pp. 3368-3379 ◽  
Author(s):  
Guiwen Wang ◽  
Pengfei Zhang ◽  
Peter Setlow ◽  
Yong-qing Li
Keyword(s):  
Heat Treatment ◽  
Raman Spectroscopy ◽  
Spore Germination ◽  
Great Majority ◽  
Lytic Enzyme ◽  
Differential Interference Contrast ◽  
Content Type ◽  
Heat Treated ◽  
Wet Heat ◽  
Kinetics Of

ABSTRACTRaman spectroscopy and differential interference contrast (DIC) microscopy were used to monitor the kinetics of nutrient and nonnutrient germination of multiple individual untreated and wet-heat-treated spores ofBacillus cereusandBacillus megaterium, as well as of several isogenicBacillus subtilisstrains. Major conclusions from this work were as follows. (i) More than 90% of these spores were nonculturable but retained their 1:1 chelate of Ca2+and dipicolinic acid (CaDPA) when incubated in water at 80 to 95°C for 5 to 30 min. (ii) Wet-heat treatment significantly increased the time,Tlag, at which spores began release of the great majority of their CaDPA during the germination ofB. subtilisspores with different nutrient germinants and also increased the variability ofTlagvalues. (iii) The time period, ΔTrelease, betweenTlagand the time,Trelease, at which a spore germinating with nutrients completed the release of the great majority of its CaDPA, was also increased in wet-heat-treated spores. (iv) Wet-heat-treated spores germinating with nutrients had higher values ofIrelease, the intensity of a spore's DIC image atTrelease, than did untreated spores and had much longer time periods, ΔTlys, for the reduction inIreleaseintensities to the basal value due to hydrolysis of the spore's peptidoglycan cortex, probably due at least in part to damage to the cortex-lytic enzyme CwlJ. (v) Increases inTlagand ΔTreleasewere also observed when wet-heat-treatedB. subtilisspores were germinated with the nonnutrient dodecylamine, while the change inIreleasewas less significant. (vi) The effects of wet-heat treatment on nutrient germination ofB. cereusandB. megateriumspores were generally similar to those onB. subtilisspores. These results indicate that (i) some proteins important in spore germination are damaged by wet-heat treatment, (ii) the cortex-lytic enzyme CwlJ is one germination protein damaged by wet heat, and (iii) the CaDPA release process itself seems likely to be the target of wet-heat damage which has the greatest effect on spore germination.

scholarly journals Calcium-Induced Activity and Folding of a Repeat in Toxin Lipase from Antarctic Pseudomonas fluorescens Strain AMS8

Toxins ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 27 ◽  
Author(s):  
Nur Shidaa Mohd Ali ◽  
Abu Bakar Salleh ◽  
Raja Noor Zaliha Raja Abd Rahman ◽  
Thean Chor Leow ◽  
Mohd Shukuri Mohamad Ali
Keyword(s):  
Fourier Transform ◽  
Secondary Structure ◽  
Pseudomonas Fluorescens ◽  
Calcium Binding ◽  
Protein Structures ◽  
Titration Calorimetry ◽  
Ftir Analysis ◽  
High Concentration ◽  
Spectroscopy Analysis ◽  
Repeat Structure

It is hypothesized that the Ca2+ ions were involved in the activity, folding and stabilization of many protein structures. Many of these proteins contain repeat in toxin (RTX) motifs. AMS8 lipase from Antarctic Pseudomonas fluorescens strain AMS8 was found to have three RTX motifs. So, this research aimed to examine the influence of Ca2+ ion towards the activity and folding of AMS8 lipase through various biophysical characterizations. The results showed that CaCl2 increased lipase activity. The far-UV circular dichroism (CD) and Fourier-transform infrared (FTIR) analysis suggested that the secondary structure content was improved with the addition of CaCl2. Fluorescence spectroscopy analysis showed that the presence of CaCl2 increased protein folding and compactness. Dynamic light scattering (DLS) analysis suggested that AMS8 lipase became aggregated at a high concentration of CaCl2.The binding constant (Kd) value from the isothermal titration calorimetry (ITC) analysis proved that the Ca2+ ion was tightly bound to the AMS8 lipase. In conclusion, Ca2+ ions play crucial roles in the activity and folding of the AMS8 lipase. Calcium binding to RTX nonapeptide repeats sequences will induced the formation and folding of the RTX parallel β-roll motif repeat structure.

scholarly journals Amino acids profile of loofah gourd Luffa cylindrica (M J Roem) seeds subjected to different heat processing methods

2020 ◽  
Vol 47 (2) ◽  
pp. 280-288
Author(s):  
M. A. Onigemo ◽  
F. A. S. Dairo ◽  
Y. A. A. Oso
Keyword(s):  
Amino Acids ◽  
Essential Amino Acids ◽  
Heat Processing ◽  
Limiting Factor ◽  
Processing Methods ◽  
Heat Treated ◽  
Wet Heat ◽  
Reduction Effect ◽  
Amino Acids Profile ◽  
Limiting Amino Acids

The major limiting factor to the utilisation of loofah gourd seeds (LGS) as food is its high content of anti-nutrient. Heat processing is one of the process of reducing the concentration of anti-nutrients in food resources which may adversely influence the amino acids contents of such resources. Raw seeds of loofah gourds (RLGS) were toasted (TLGS), boiled (BLGS) and cooked (CGLS) and analysed for the amino acids content. The amino acids score, the essential amino acids score and the predicted (P-PER) of the raw and heat treated RLGS were calculated using standard equations. Results revealed that heat treatment significantly reduced (P<0.05) the essential amino acids, total sulphur containing amino acids and total basic amino acids while significantly (P<0.05) increasing the total amino acids, and total non-essential amino acids. cysteine is the most reduced amino acids and toasting had the highest reduction effect on the amino acids. P-PER of LGS were significantly enhanced by heat processing. Glutamic acid and aspartic acid were the most abundant amino acids while cysteine and methionine were the major limiting amino acids in the raw and processed LGS. In conclusion, heat processing enhances the nutritional potentials of LGS and wet heat processing boiling and cooking are the most preferred processing methods for loofah gourd seed.

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