scholarly journals Differences In The Properties of Extracellular Polymeric Substances Responsible For PAH Degradation Isolated From Mycobacterium Gilvum SN12 Grown On Pyrene And Benzo[a]pyrenee

2021 ◽  
Author(s):  
Chunyun Jia ◽  
Changfeng Liu ◽  
Zongqiang Gong ◽  
Xiaojun Li ◽  
Zijun Ni
Keyword(s):  
Smooth Surface ◽  
Extracellular Polymeric Substances ◽  
Emulsifying Activity ◽  
Compact Structure ◽  
Heating Method ◽  
First Report ◽  
Texture Profile ◽  
Bacterial Cultures ◽  
Pah Biodegradation ◽  
Main Components

Abstract To evaluate the differences in the characteristics of extracellular polymeric substances (EPS) secreted by Mycobacterium gilvum SN12 (M.g. SN12) cultured on pyrene (Pyr) and benzo[a]pyrene (BaP) , heating method was used to extract EPS from M.g. SN12, and the composition, emulsifying activity and morphology of EPS extracts were investigated in this study. It was indicated that EPS extracts varied significantly with the addition of Pyr or BaP to the bacterial cultures. Concentration of proteins and carbohydrates, the main components of the EPS extracts, first increased and then decreased, with an increase in the concentration of Pyr (0–120 mg L-1) and BaP (0–120 mg L-1). A similar trend was observed for the emulsifying activity of the EPS extracts. EPS extracted from all cultures exhibited a compact structure with smooth surface, except EPS extracted from BaP-grown M.g. SN12, which exhibited a more fragile and softer surface. These findings suggest that Pyr and BaP had different influence on the properties of isolated EPS, providing insights into the mechanism underlying PAH biodegradation by some bacteria secreting EPS. To the best of our knowledge, this is the first report on the texture profile of EPS samples extracted from M.g. SN12 grown on PAHs.

scholarly journals Essential Oil Composition of Helichrysum conglobatum from Cyprus

2016 ◽  
Vol 11 (10) ◽  
pp. 1934578X1601101
Author(s):  
Kaan Polatoğlua ◽  
Betül Demirci ◽  
İhsan Çalιş ◽  
Kemal Hüsnü Can Başer
Keyword(s):  
Essential Oil ◽  
Essential Oil Composition ◽  
Oil Yield ◽  
Hexadecanoic Acid ◽  
Oil Composition ◽  
Tetradecanoic Acid ◽  
First Report ◽  
Aerial Parts ◽  
Main Components ◽  
Essential Oil Yield

The essential oil of aerial parts of Helichrysum conglobatum (Viv.) Steudel. (Asteraceae) from Cyprus was analyzed by GC and GC-MS. The essential oil yield was 0.01, v/w. Forty five compounds were identified in the oil comprising 96.1% of the total. The essential oil was mainly composed of sesquiterpene type compounds and oxygenated sesquiterpene derivatives. The main components of the oil were β-caryophyllene (14.6%), γ-curcumene (14.1%), hexadecanoic acid (13.5%), tetradecanoic acid (7.5%), rosifoliol (5.4%) and δ-cadinene (5.3%). This is the first report on the essential oil composition of H. conglobatum from Cyprus.

scholarly journals Biosynthesis of Extracellular Polymeric Substances by the Marine BacteriumSaccharophagus degradansunder Different Nutritional Conditions

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Yolanda González-García ◽  
Alejandra Heredia ◽  
Juan Carlos Meza-Contreras ◽  
Froylán M. E. Escalante ◽  
Rosa María Camacho-Ruiz ◽  
...  
Keyword(s):  
Carbon Source ◽  
Synergistic Effect ◽  
Maximum Concentration ◽  
Marine Bacterium ◽  
Extracellular Polymeric Substances ◽  
Mineral Medium ◽  
Saccharophagus Degradans ◽  
First Report ◽  
Nutritional Conditions ◽  
New Feature

The effect of carbon source, carbon to nitrogen (C/N) ratio, and limitation in nutrients (N, P, K, Ca, Mg, and Fe) on extracellular polymeric substances (EPS) synthesis by the marine bacteriumSaccharophagus degradanswas studied. This strain was able to grow in mineral medium and produce EPS with different efficiency according to the C source used (g EPS/L): glucose or starch (1.5 ± 0.2); galactose, sucrose, or xylose (0.7 ± 0.2); and fructose (0.3 ± 0.1). The C/N ratio (glucose/ammonium) had a significant effect on EPS biosynthesis due to its production rise as the C/N ratio increased from 3 to 100 (0.7 to 2.1 g EPS/L). It was also observed that limitation in nutrients such as N, P, K, Ca, Mg, and Fe also favored EPS biosynthesis. When taking into account both factors (C/N ratio, 100; nutrients limitation, 50%) a positive synergistic effect was noted on EPS production since under these conditions the maximum concentration obtained was 4.12 ± 0.3 g/L after 72 h of culture. The polymer was found to be a polysaccharide of mainly glucose, mannose, and galactose. This is the first report on EPS production byS. degradanswhich is a new feature of this versatile marine bacterium.

Development of a continuous protein and polysaccharide measurement method by Sequential Injection Analysis for application in membrane bioreactor systems

2007 ◽  
Vol 56 (6) ◽  
pp. 163-171 ◽  
Author(s):  
R. Mehrez ◽  
M. Ernst ◽  
M. Jekel
Keyword(s):  
Extracellular Polymeric Substances ◽  
Screening Tests ◽  
Sequential Injection Analysis ◽  
Lower Sensitivity ◽  
Sequential Injection ◽  
Good Correspondence ◽  
Automated Method ◽  
Lowry Method ◽  
Main Components ◽  
Lowry Assay

Polysaccharides and proteins are the main components of extracellular polymeric substances, which are considered to give a major contribution to the overall fouling potential of the MBR system. This work focuses on the automation of spectrophotometrical assays for protein and polysaccharide determination for on-line measurement in MBR. Sequential Injection Analysis (SIA) was identified as more suitable for continuous measurements. In screening tests the selection of an appropriate assay for the successful automation by means of SIA was carried out. Lowry Assay and Dubois Assay were chosen for protein and polysaccharide determination. Lowry Assay could be successfully automated by means of SIA. The automated method shows a lower sensitivity than the manual Lowry method, what can be contributed to specific characteristic of SIA. The confidence limit was calculated to 2.8 mg/L. The automated method shows in validation tests good correspondence with protein concentrations measured with the manual assay (R2=0.971). The successful establishment of the Dubois Assay for polysaccharides failed so far due to sensitivity problems.

scholarly journals Production and Biotechnological Potential of Extracellular Polymeric Substances from Sponge-Associated Antarctic Bacteria

2017 ◽  
Vol 84 (4) ◽  
Author(s):  
Consolazione Caruso ◽  
Carmen Rizzo ◽  
Santina Mangano ◽  
Annarita Poli ◽  
Paola Di Donato ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Survival Ratio ◽  
Uronic Acids ◽  
Emulsifying Activity ◽  
Biotechnological Potential ◽  
Content Type ◽  
Antarctic Bacteria ◽  
Emulsification Index ◽  
Potential Applications ◽  
Commercial Polymers

ABSTRACTFour sponge-associated Antarctic bacteria (i.e.,Winogradskyellasp. strains CAL384 and CAL396,Colwelliasp. strain GW185, andShewanellasp. strain CAL606) were selected for the highly mucous appearance of their colonies on agar plates. The production of extracellular polymeric substances (EPSs) was enhanced by a step-by-step approach, varying the carbon source, substrate and NaCl concentrations, temperature, and pH. The EPSs produced under optimal conditions were chemically characterized, resulting in a moderate carbohydrate content (range, 15 to 28%) and the presence of proteins (range, 3 to 24%) and uronic acids (range, 3.2 to 11.9%). Chemical hydrolysis of the carbohydrate portion revealed galactose, glucose, galactosamine, and mannose as the principal constituents. The potential biotechnological applications of the EPSs were also investigated. The high protein content in the EPSs fromWinogradskyellasp. CAL384 was probably responsible for the excellent emulsifying activity toward tested hydrocarbons, with a stable emulsification index (E24) higher than those recorded for synthetic surfactants. All the EPSs tested in this work improved the freeze-thaw survival ratio of the isolates, suggesting that they may be exploited as cryoprotection agents. The addition of a sugar in the culture medium, by stimulating EPS production, also allowed isolates to grow in the presence of higher concentrations of mercury and cadmium. This finding was probably dependent on the presence of uronic acids and sulfate groups, which can act as ligands for cations, in the extracted EPSs.IMPORTANCETo date, biological matrices have never been employed for the investigation of EPS production by Antarctic psychrotolerant marine bacteria. The biotechnological potential of extracellular polymeric substances produced by Antarctic bacteria is very broad and comprises many advantages, due to their biodegradability, high selectivity, and specific action compared to synthetic molecules. Here, several interesting EPS properties have been highlighted, such as emulsifying activity, cryoprotection, biofilm formation, and heavy metal chelation, suggesting their potential applications in cosmetic, environmental, and food biotechnological fields as valid alternatives to the commercial polymers currently used.

scholarly journals The unusual sclerotium of Rhizopogon roseolus reported from pure cultures

2021 ◽  
Vol 948 (1) ◽  
pp. 012018
Author(s):  
P Putra ◽  
R Hermawan ◽  
T Aimi ◽  
N Shimomura
Keyword(s):  
Smooth Surface ◽  
Current Knowledge ◽  
Morphological Observation ◽  
Bacterial Cells ◽  
Rhizopogon Roseolus ◽  
First Report ◽  
Pure Cultures ◽  
Luria Agar

Abstract During the assessment of mycelial cords of Rhizopogon roseolus on poor nutrient of Modified Melin-Norkrans (MMN) medium, we found some sclerotia produced on the surface of extraradical mycelia. The sclerotia were 0.27 mm in average of diameter and produced after 2 months of incubation. The current knowledge defined the sclerotium as mass of hyphae and normally having no spores in or on it. However, we found and suspected the small structures like spores (1-1.5 um) inside the sclerotium. These structures were ellipsoid, hyaline, with the smooth surface. We then incubated the sclerotium and these small structures on TM7 detecting medium whether they can produced the secondary mycelia of R. Roseolus, but no germination was observed. Interestingly, the bacterial colonies which connected to hyphae of sclerotium were appeared. The colonies were transferred to Luria agar (LA) medium. The morphological observation of bacterial cells from TM7 and LA confirmed that they were the same as small structures inside the sclerotium. This is the first report on production of unusual sclerotium of R. roseolus in pure cultures. Further study is required to reveal the role of bacteria on production of sclerotium of R. Roseolus.

scholarly journals OPTIMIZACION DE UNA FORMULACIÓN DE BUTIFARRA DULCE SECA CON CARNE DE LLAMA, PECANAS Y KAÑIWA

2021 ◽  
Vol 23 (2) ◽  
pp. 77-84
Author(s):  
Bettit Karim Salvá Ruiz ◽  
◽  
Carlos César Augusto Elías-Peñafiel ◽  
Judith Larico Condori ◽  
◽  
...  
Keyword(s):  
Design Method ◽  
Desirability Function ◽  
Pork Meat ◽  
Variable Response ◽  
Sample Mean ◽  
Texture Profile ◽  
Degree Of Satisfaction ◽  
Lama Glama ◽  
Objective Value ◽  
Main Components

In the formulation of dried sweet sausage, pork meat and fat are traditionally used, which can be replaced by healthy products such as pecans (Carya illinoinensis) and kañiwa (Chenopodium pallidicaule); as well as llama meat (Lama glama) that is low in fat and cholesterol. For this reason, the present investigation aimed to optimize a formulation of dried sweet sausage considering three main components: llama meat, kañiwa flour and pecans. The D-Optimal mixture design method of the Design-Expert®7 program was applied, obtaining fourteen formulations. For each formulation, color, water activity and texture profile were evaluated. Only the cohesiveness fit a meaningful mathematical model. Subsequently, the optimization of the variable response was carried out, using the desirability function of the "objective value" type, so that the product could resemble the target (sausage made with pork meat and fat). In the sensory analysis of the optimal formulation, four sensory attributes were evaluated: color, odor, taste and texture, in a Z test to demonstrate whether the sample mean of the degree of satisfaction for each attribute of the product was acceptable or not. All these attributes are believed to be above the population mean taken as a target. In conclusion, the optimal formula was composed of 80% llama meat and 20% pecans, observing that kañiwa flour did not improve the texture and color of the sausage.

Effect of Ammonia on CeO2 Microspheres Prepared by Internal Gelation Process

2018 ◽  
Vol 281 ◽  
pp. 9-14
Author(s):  
Xue Qiang Ding ◽  
Jing Tao Ma ◽  
Xing Yu Zhao ◽  
Shao Chang Hao ◽  
Chang Sheng Deng ◽  
...  
Keyword(s):  
Grain Size ◽  
Surface Morphology ◽  
Cerium Dioxide ◽  
Smooth Surface ◽  
Molar Ratio ◽  
Internal Gelation ◽  
Compact Structure ◽  
Gelation Process ◽  
The Stability

The internal gelation process was used to prepare cerium dioxide microspheres. The effect of ammonia on the stability of the precursor solutions was investigated with the NH3∙H2O/Ce (NH4)2(NO3)6 molar ratio from 0 to 1.25. The surface morphology and microstructure of the sintered CeO2 microspheres were analyzed. With the increase of NH3∙H2O/Ce (NH4)2(NO3)6 molar ratio, the solutions became more unstable, which indicated that their gelation was initiated. When the NH3∙H2O/Ce (NH4)2(NO3)6 ratio varied from 0 to 0.75, the surface of the microspheres became rougher and grain size became larger. Further increase in the NH3∙H2O/Ce (NH4)2(NO3)6 ratios to 1 and 1.25 led to CeO2 microspheres with smooth surface and compact structure.

A New Incremental Bending System to Form Curved Metal Plate by Experiment and Finite Element Simulation

2018 ◽  
Author(s):  
Xiaobing Dang ◽  
Kai He ◽  
Feifei Zhang ◽  
Qiyang Zuo ◽  
Ruxu Du
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Conventional Method ◽  
Smooth Surface ◽  
Metal Plate ◽  
Basic Process ◽  
Important Process ◽  
High Quality ◽  
Heating Method ◽  
Element Simulation

Bending curved metal plate is an important process for many heavy industries such as shipbuilding. It is a basic process to manufacture hull surface. The conventional method is the so-called line heating method, which is not only labor intensive but also inefficient and error-prone. We have presented a new method of incremental bending. In this paper the incremental bending system is explained from its hardware and software. A kind of curved metal plate is formed by experiment and finite element simulation. The manufactured workpiece is of high quality with smooth surface. The presented method can be successfully used to form curved metal plate. It is a highly flexible forming method. It would have a wide application in industry.

scholarly journals Essential Oil of Piper oradendron from the Pacific Slope of Guatemala

2019 ◽  
Vol 14 (1) ◽  
pp. 1934578X1901400 ◽  
Author(s):  
José V. Martínez-Arévalo ◽  
Sully M. Cruz ◽  
Miriam A. Apel ◽  
Amélia T. Henriques ◽  
Armando Cáceres
Keyword(s):  
Chemical Composition ◽  
Essential Oil ◽  
Essential Oils ◽  
Endemic Species ◽  
First Report ◽  
The Pacific ◽  
Three Samples ◽  
Germacrene D ◽  
Pacific Slope ◽  
Main Components

Essential oils of leaves of the endemic species Piper oradendron Trel. & Standl. (Piperaceae) were obtained from three sites of the Guatemalan Pacific slope. The yields of the essential oils obtained by hydrodistillation varied from the site of collection (0.4-1.4%). The GC/MS analysis showed that sample A (Samayac) had up to 53 peaks that were identified, B (Popoyá) showed 31 peaks and C (Bulbuxyá) showed 22; major constituents were similar in the three samples, including α- and β-pinene (28.3-46.9%), germacrene D (10.7-22.7%), and iso-spathulenol (10.2-22-3%). This is the first report on the chemical composition of the essential oil of samples of P. oradendron from different provenances of Guatemala, suggesting little variability in its main components.

Sign in / Sign up

Export Citation Format

Share Document