scholarly journals Free-standing spider silk webs of the thomisid Saccodomus formivorus are made of composites comprising micro- and submicron fibers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Christian Haynl ◽  
Jitraporn Vongsvivut ◽  
Kai R. H. Mayer ◽  
Hendrik Bargel ◽  
Vanessa J. Neubauer ◽  
...  
Keyword(s):  
Spider Silk ◽  
Structural Integrity ◽  
Chemical Properties ◽  
Free Standing ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
Crab Spiders ◽  
Ambush Predators ◽  
The Web ◽  
And Chemical Properties

Abstract Our understanding of the extraordinary mechanical and physico-chemical properties of spider silk is largely confined to the fibers produced by orb-weaving spiders, despite the diversity of foraging webs that occur across numerous spider families. Crab spiders (Thomisidae) are described as ambush predators that do not build webs, but nevertheless use silk for draglines, egg cases and assembling leaf-nests. A little-known exception is the Australian thomisid Saccodomus formivorus, which constructs a basket-like silk web of extraordinary dimensional stability and structural integrity that facilitates the capture of its ant prey. We examined the physical and chemical properties of this unusual web and revealed that the web threads comprise microfibers that are embedded within a biopolymeric matrix containing additionally longitudinally-oriented submicron fibers. We showed that the micro- and submicron fibers differ in their chemical composition and that the web threads show a remarkable lateral resilience compared with that of the major ampullate silk of a well-investigated orb weaver. Our novel analyses of these unusual web and silk characteristics highlight how investigations of non-model species can broaden our understanding of silks and the evolution of foraging webs.

scholarly journals Effect of Slice Weight and Soaking Time on the Physico-Chemical Properties of Cassava Flour (Manihotesculentus) used for Bakery Products

2021 ◽  
pp. 10-24
Author(s):  
C. R. Abah ◽  
C. N. Ishiwu ◽  
J. E. Obiegbuna ◽  
E. F. Okpalanma ◽  
C. S. Anarado
Keyword(s):  
Chemical Properties ◽  
Process Variables ◽  
Soaking Time ◽  
Cassava Flour ◽  
Baked Goods ◽  
Cassava Root ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
And Chemical Properties

Quality cassava(Manihotesculentus, Crantz) flour is often influenced by process variables such as slice weight and soaking time which may affect its nutritional quality. In this study, the effect of process variables (slice weight and soaking time) on quality of cassava flour was carried out. Cassava root was peeled, washed and cut into varied sizes (25.86 - 54.14 g) and soaked at varied time (7.03 - 40.97 h). The proximate composition, physical and chemical properties of the flour were carried out using standard methods. The result in our findings showed that slice weight and soaking time had significant increase (p<0.05) on the proximate and physico-chemical properties of the flour.The amylose and amylopectin content of the flour increased with increasing soaking time while the hydrogen cyanide content decreased with increase in soaking time. Overall, the quality cassava flour displayed desirable properties for its incorporation into baked goods.

scholarly journals Physical and Chemical Properties and Methods of Control of Pantoprazol Sodium Sesquihydrate (Review)

2020 ◽  
Vol 9 (1) ◽  
pp. 46-53
Author(s):  
V. A. Shelekhova ◽  
K. R. Savelyeva ◽  
S. V. Polyakov ◽  
V. N. Shestakov
Keyword(s):  
Chemical Properties ◽  
Reaction Products ◽  
Chemical Methods ◽  
Spectrophotometric Methods ◽  
Physico Chemical ◽  
Inflammatory Drugs ◽  
Physical And Chemical ◽  
Direct Spectrophotometry ◽  
Methods Of Control ◽  
And Chemical Properties

Introduction. Pantoprazole sodium sesquihydrate is a proton pump inhibitor. This substance is used in the treatment of peptic ulcer of the duodenum or stomach in the acute phase, including those associated with the use of non-steroidal anti-inflammatory drugs.Text. Pantoprazole is sodium 5-(difluoromethoxy)-2-[(RS)-[(3,4-dimethoxypyridin-2-yl)methyl]sulfinyl]benzimidazol-1-ide sesquihydrate in its structure. The substance is readily soluble in water and ethyl alcohol. The identification of pantoprazole is confirmed by infrared absorption spectrophotometry, as well as by a positive reaction to sodium ion. For the assay of this substance chemical and physico-chemical methods are used. The first group of methods includes titration in a non-aqueous medium with perchloric acid and permanganatometry. Physico-chemical methods used for pantoprazole assay are spectrophotometry and HPLC. The most commonly used method is direct spectrophotometry associated with the measurement of optical density at a wavelength of the maximum absorption of pantoprazole in various solvents. In addition, spectrophotometric methods of assay are known, based on the study of the absorption of colored pantoprazode reaction products. The derivative spectrophotometry is used for the analysis of its preparations. The control of the content of impurities and pantoprazole in the substance and its dosage forms is carried out, as a rule, using HPLC.Conclusion. An analysis of the literature has shown that this substance is unstable. Therefore, this feature of pantoprazole must be considered when choosing excipients when developing a dosage form. The preferred method for analyzing pantoprazole preparations is HPLC, since it is possible to determine the substance in the presence of other compounds, which will allow one to control the quantitative content and stability of pantoprazole in the preparation.

scholarly journals Physico-Chemical Properties of Purified Carboxylesterase from the Seeds of Tamarindus indica

2021 ◽  
pp. 42-58
Author(s):  
S. Kantharaju ◽  
M. Mylarappa
Keyword(s):  
Molecular Weight ◽  
Gel Filtration ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Tamarindus Indica ◽  
Physico Chemical ◽  
Sds Page ◽  
Physical And Chemical ◽  
Naphthyl Acetate ◽  
And Chemical Properties

The present work is focus on physical and chemical properties of purified Carboxylesterase using the Seeds of Tamarindus Indica.The esterases are extracted from the germinating tamarind seeds using 50 mM phosphate buffer, pH 7 and purified. The Km with α-naphthyl acetate, β-naphthyl acetate and α-naphthyl butyrate as the substrates is 28.6 μM, 22.2 μM and 26.7 μM respectively. The Vmax for the same substrates is 7.1 x 10-3 µmole/min, 7.41 x 10-3 µmole/min and 8.00 x 10-3 µmole/min respectively. The enzymes optimally active at pH 7.0 and are stable between pH 5.0 to 8.0. The optimum temperature of esterase activity is 40˚C. The molecular weight of 27.5 kD as determined by SDS-PAGE, both in the presence and absence of β-mercaptothanol and is in close agreement with the molecular weight determined by gel-filtration on Sephadex G-100 (26.9 kD).

scholarly journals Impacts of the Physico-chemical Properties of Al-Chibayish Water Marshes on The Biodiversity of Phytoplankton

2021 ◽  
pp. 402-414
Author(s):  
Firas AbdulHassan Jaafar ◽  
Ahmed Saad Abdulwahhab
Keyword(s):  
Aquatic Ecosystems ◽  
Phytoplankton Community ◽  
Chemical Properties ◽  
P Value ◽  
Total Density ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
Clear Increase ◽  
And Chemical Properties

Phytoplankton, as one of the most important primary producers in aquatic ecosystems, has been widely used to indicate the health of ecosystems. Nine physico-chemical parameters of water, as well as the phytoplankton community, of Al-Chibayish marsh were studied. Samples were collected from four sites and analyzed every two months from January to October 2019.     Seasonal variations in physical and chemical properties were observed at all sites during the study period. The results indicated that 154 species of phytoplankton were recorded. The highest percentage of species was recorded to be 64.28% for Bacillariophyceae (diatoms) (Centrales 3.24% and Pennales 61.03%), followed by Chlorophyceae (16.23%), Cyanophyceae (11.68%), and Charophyceae and Euglenophyceae (3.24%), while Pyrrophyceae recorded the lowest value (1.29%) The numbers of phytoplankton species were 102, 94, 102, 99 in sites 1, 2, 3 and 4 ,respectively, during the study period.  The total density of phytoplankton ranged from 223.769 cells x103 during January to 2784.693 cells x103 during September in site 2, with a clear increase during March and September, while the lowest number was 223.796 - 237.248 cells x103 in January and May, respectively. The dominance of diatoms was observed in all sites by 49.07% of the total density of phytoplankton, while the lowest abundance was 0.04% for the Pyrrophyceae. The results of the statistical analysis showed significant differences among sites and months, concerning the physical, chemical, and biological factors measured during the study period, at p-value <0.05.

Onion-Like Carbon Nanostructures: An Overview of Bio-Applications

2019 ◽  
Vol 26 (38) ◽  
pp. 6896-6914 ◽  
Author(s):  
Diana M. Bobrowska ◽  
Piotr Olejnik ◽  
Luis Echegoyen ◽  
Marta E. Plonska-Brzezinska
Keyword(s):  
Physicochemical Properties ◽  
Carbon Nanostructures ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Unusual Structure ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
And Chemical Properties

: This article presents a brief review of the knowledge concerning onion-like carbons (OLCs). These nanostructures are some of the most fascinating carbon forms due to their unusual structure and physico-chemical properties. Generally, OLCs consist of a hollowspherical fullerene core surrounded by concentric graphitic layers with increasing diameter. Nevertheless, they can have different size, shape and type of core, which determine their physicochemical properties. In this article, we review the most important literature reports in this area and briefly describe these nanostructures, their physical and chemical properties and their potential uses with a focus on biomedicine.

Research on physico-chemical properties of sugars and sugar crystallization at the University of Chemistry and Technology in Prague

2020 ◽  
pp. 294-298
Author(s):  
Z. Bubnik ◽  
P. Kadlec ◽  
E. Sarka ◽  
V. Pour ◽  
A. Hinkova ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Main Research ◽  
Research Areas ◽  
Research Activities ◽  
Physico Chemical ◽  
Wide Range ◽  
The University ◽  
Physical And Chemical ◽  
Kinetics Of ◽  
And Chemical Properties

This paper represents a summary of most important research activities in sucrose crystallization, in which the Department of Carbohydrates and Cereals, part of the University of Chemistry and Technology (UCT) Prague, has been involved over the last 25 years. A wide range of these projects has been carried out in cooperation with other research institutes, universities and industrial partners. These activities can be divided into four main research areas that are interconnected and support each other. – Physical and chemical properties of sucrose and sugar solutions; – Growth kinetics of sugar crystals in pure and technical sugar solutions; – Simulation and mathematical modeling of new processes and technologies; – Experimental work for industry and cooperation with industrial partners.

scholarly journals Physico-chemical Evaluation of Some Introduced Date Fruits Cultivars grown under Sudanese conditions

2015 ◽  
Vol 3 (4) ◽  
pp. 731-736
Author(s):  
Islam K. Saeed ◽  
Fatima A. El-Rauof ◽  
H.D. Dawoud
Keyword(s):  
Crude Protein ◽  
Reducing Sugars ◽  
Chemical Properties ◽  
Fruit Weight ◽  
Chemical Evaluation ◽  
Physical Chemical ◽  
Physico Chemical ◽  
Fruit Samples ◽  
Physical And Chemical ◽  
And Chemical Properties

Fruit samples of five date cultivars, three cultivars of them were introduced from Emirates Tissue culture Laboratory-Alien Abu Dhabi and cultivated in Haj-Bashir orchard - Khartoum region were collected at the beginning of the Tamar stages. The present study was aimed to investigate the physical and chemical properties. The results showed that the physical characteristics like fruit weight, length, flesh thickness, seed weight differed significantly (P < 0.05) between the various cultivars. Chemical analysis indicated small amounts of crude fiber, crude protein, Fat and ash, while sugars predominated. In general the majority of date cultivars investigated was found to be of the soft date type characterized by the dominance of reducing sugars. The performance of introduced cultivars was well when compared with the indigenous cultivar of most physical, chemical characteristics and general evaluation.Int J Appl Sci Biotechnol, Vol 3(4): 731-736

scholarly journals GENETIC DIVERSITY AND FRUIT QUALITY OF SEVERAL POMELO “JERUK BALI” (Citrus grandis L. Osbeck) CULTIVARS IN BALI

2017 ◽  
Vol 5 (1) ◽  
pp. 43
Author(s):  
Ida Bagus Komang Mahardika ◽  
I Nyoman Rai ◽  
Made Sudiana Mahendra ◽  
Rindang Dwiyani
Keyword(s):  
Genetic Diversity ◽  
Rapd Markers ◽  
Morphological Character ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Physico Chemical ◽  
Chemical Content ◽  
Physical And Chemical ◽  
And Chemical Properties

This study aimed to determine the genetic diversity and fruits quality of the "Jeruk Bali" cultivars grown in Bali. This research was conducted in all regencies and city in Bali, during 2016. Furthermore, several cultivars of “Jeruk Bali” were genetically analyzed based on RAPD markers using 10 primers. Analysis of the quality of fruit is based on physical properties and chemical content. Eighteen cultivars of "Jeruk Bali" obtained have a fruit morphological character with round, short round, and piriform fruit shapes, which are red, pink, cream and white flesh color. RAPD analysis results at 53% similarity level are grouped into 5 groups. The first group was only one cultivar, the second group consisted of 13 cultivars, the third and fourth groups were only one cultivar, while the fifth group consisted of two cultivars. The analysis of the diversity between cultivars based on the combination of physical and chemical properties of the fruit with hierarchy method on similarity level about 85% in a group is obtained by 4 (four) groups. Groupings by combination of physical and chemical properties of the fruit are not synchronized in their entirety with dendograms based on their genetic diversity. This illustrates the physico-chemical properties of “Jeruk Bali” fruit in general is not fully genetical expressed, but also influenced by conditions of environmental growth.

Research on the Correlation between Biodiesel's Composition and Physical & Chemical Properties

2015 ◽  
Vol 737 ◽  
pp. 65-70
Author(s):  
Dong Bo Yang ◽  
Xing Kai Meng ◽  
Xia Zhang ◽  
Jing Jing Tian
Keyword(s):  
Cetane Number ◽  
Chemical Properties ◽  
Rapid Test ◽  
Least Square Method ◽  
Least Square ◽  
Physical And Chemical Properties ◽  
Cold Filter Plugging Point ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
And Chemical Properties

Biodiesel's composition has a significant effect on biodiesel’s main physical and chemical properties. Through the test and analysis of the composition and the physical & chemical properties of 5 types of biodiesel, this paper uses linear regression model and least square method to conduct a research on the correlation between biodiesel's physical and chemical properties such as density, cold filter plugging point (CFPP), cetane number and kinematic viscosity, biodiesel's FAME content and the number of double bonds in its UFAME, and establishes correlation functions for relevant indexes, providing a theoretical basis for rapid test of biodiesel’s physico-chemical performance index.

scholarly journals Physico-chemical and Functional Properties of Two Jackfruit (Artocarpus heterophyllus Lam.) Varieties in Eastern Visayas, Philippines

2017 ◽  
pp. 100-106 ◽  
Author(s):  
Lorina Galvez ◽  
Erlinda Dizon
Keyword(s):  
Functional Properties ◽  
Total Phenolics ◽  
Chemical Properties ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Tannin Content ◽  
Physico Chemical ◽  
Total Titratable Acidity ◽  
Physical And Chemical ◽  
And Chemical Properties

Quality is a wide-ranging concept determined by many factors. It is a composite of those physical and chemical properties of the material which govern its acceptability and processing suitability. This study aimed to determine the physico-chemical and functional properties of the two jackfruit varieties (EVIARC Sweet and AES-2) grown in Eastern Visayas, Philippines. Fresh ripe jackfruit varieties were subjected to physico-chemical properties and functional component analyses following standard protocols. The two jackfruit varieties were found to have the following properties: the pH were 4.80 and 5.50; total soluble solids (TSS), 24.00 and 22.60oB; total titratable acidity (TTA), 0.33% and 0.12% citric acid; moisture content (MC), 77.30% and 75.96% (wb); total phenolics (TP), 127.73 and 125.91mg CE/100g; tannin content (TC),127.73 and 208.72 mg VE/100g; total reducing sugar (TRS), 15.43% and14.38%; total sulfur (TS), 0.36 and 0.57ppm; and antioxidant activity (AOA), 39.55 and 52.35% LP (lipid peroxidation) for EVIARC sweet and AES-2, respectively. Variety significantly affects the pH, TSS, TTA, %MC, TC, TRS, TS and AOA. Non-significance was noted on their TP contents.

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