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Author(s):  
Ruohao Tang ◽  
Xiaowei Peng ◽  
Caihong Weng ◽  
Yejun Han

Cupriavidus necator H16 is an ideal strain for polyhydroxybutyrate (PHB) production from CO 2 . Low-oxygen-stress can induce PHB synthesis in C. necator H16 while reducing bacterial growth under chemoautotrophic culture. The optimum growth and PHB synthesis of C. necator H16 cannot be achieved simultaneously, which restricts PHB production. The present study was initiated to address the issue through comparative transcriptome and gene function analysis. Firstly, the comparative transcriptome of C. necator H16 chemoautotrophically cultured under low-oxygen-stress and non-stress conditions was studied. Three types of transcription different genes were discovered: PHB enzymatic synthesis, PHB granulation, and regulators. Under low-oxygen-stress condition, acetoacetyl-CoA reductase gene phaB2 , PHB synthase gene phaC2 , phasins genes phaP1 and phaP2 , regulators genes uspA and rpoN were up-regulated 3.0, 2.5, 1.8, 2.7, 3.5, 1.6 folds, respectively. Secondly, the functions of up-regulated genes and their applications in PHB synthesis were further studied. It was found that the over-expression of phaP1 , phaP2 , uspA , and rpoN can induce PHB synthesis under non-stress condition, while phaB2 and phaC2 have no significant effect. Under the optimum condition, PHB percentage content in C. necator H16 was respectively increased by 37.2%, 28.4%, 15.8%, and 41.0% with the over-expression of phaP1 , phaP2 , uspA , and rpoN , and the corresponding PHB production increased by 49.8%, 42.9%, 47.0%, and 77.5% under non-stress chemoautotrophic conditions. Similar promotion by phaP1 , phaP2 , uspA , and rpoN was observed in heterotrophically cultured C. necator H16. The PHB percentage content and PHB production were respectively increased by 54.4% and 103.1% with the over-expression of rpoN under non-stress heterotrophic conditions. Importance Microbial fixation of CO 2 is an effective way to reduce greenhouse gases. Some microbes such as C. necator H16 usually accumulate PHB when they grow under stress. Low-oxygen-stress can induce PHB synthesis when C. necator H16 is autotrophically cultured with CO 2 , H 2 , and O 2 , while under stress, growth is restricted and total PHB yield is reduced. Achieving the optimal bacterial growth and PHB synthesis at the same time is an ideal condition for transforming CO 2 into PHB by C. necator H16. The present study was initiated to clarify the molecular basis of low-oxygen-stress promoting PHB accumulation and to realize the optimal PHB production by C. necator H16. Genes up-regulated under non-stress conditions were identified through comparative transcriptome analysis and over-expression of phasin and regulator genes were demonstrated to promote PHB synthesis in C. necator H16.


2021 ◽  
Vol 843 (1) ◽  
pp. 012007
Author(s):  
V V Kovtunov ◽  
N A Kovtunova ◽  
A S Popov

Abstract The current paper presents the study results of protein percentage, content of lysine and starch in the collection samples of grain sorghum of various ecological and geographical origin. It was determined that the seed protein percentage in the grain sorghum samples varied from 9.0 to 13.5%. The highest values were identified in the samples from Russia (KiM, Krymbel, Krusta, Ros’), Ukraine (Pioner 412/Milovskoe 6, No. 13-13, Pioner 878/Genicheskoe brown 129) and China (KX 8, No. 26-14) with 13.0-13.5%. The lysine content in protein of the studied samples was 2.5-4.3%, while the value of the standard variety Zernogradskoe 88 was 3.17% with the standard deviation of 0.24%. The maximum content (3.8-4.3%) was identified in the samples Early Hegari (Peru), Line ExF3 IS12606 (Australia), DN-35f (Ukraine), CS-175 (Philippines), H.S.-21 (Romania), Sorghum k-9553 (Korea). The starch content in seed of the collection samples varied within 70.2-77.5%. The highest intragroup values were showed by the samples from Peru (73.9%), Australia (73.8%), France (73.0%), Senegal (73.4%).


Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6549
Author(s):  
Jian Song ◽  
Jiaxin Ma ◽  
Fengyan Li ◽  
Lina Chai ◽  
Wenfu Chen ◽  
...  

In order to explore the fractal characteristics of particle size distribution (PSD) of various minerals in loess and lime-treated loess, the Q4 undisturbed loess and lime-treated loess were studied. From the perspective of multi-scaled microstructure, the internal characteristics of loess were observed and the regularity statistics were carried out from a macroscopic view. Fractal theory was used to quantitatively study the distribution of mineral particles in undisturbed loess and lime-treated loess. It was found that the skeleton particles of undisturbed loess were obvious and the structure of soil was loose. While that of lime-treated loess decreased, the fine particles were connected with each other, and the structure of soil changed from loose to dense. The three mineral particles in the undisturbed loess and lime-treated loess did not accord with the single fractal distribution characteristics, but the total particles had fractal characteristics. The percentage content of the mineral particles in the soil varied greatly with the particle size. In addition, the non-uniform degrees of mineral particles in the two soils from large to small were carbonate minerals of lime-treated loess, carbonate minerals of undisturbed loess, quartz minerals of lime-treated loess, feldspar mineral of lime-treated loess, feldspar mineral of the undisturbed loess, and the quartz mineral of the undisturbed loess. This paper provided a basis for the future study of the different soil mechanical properties of undisturbed loess and lime-treated loess.


2021 ◽  
Vol 910 (1) ◽  
pp. 012093
Author(s):  
Azhin Bakhtyar Mahmood Abdulrahman ◽  
Huda Jamal Mhamad ◽  
Sonia Sardar Talb ◽  
Ali Muhi Aldeen Omar Aljabary

Abstract In this study, four pomegranate cultivars were selected in Halabja City. Their physical properties such as peel, arils, juice, seed, and juice concentrate percentage, chemical properties, and some phenolic and sugars compounds of the juices and juices concentrate was compared among all cultivars. Of all four cultivars (Wonderful, Swra hanar, Salakhani, and Kaua hanar), Wonderful and Salakhani presented the highest pH values in juice and juice concentrate and they obtained a signififcant percentage of juice concentrate, total sugars, total anthocyanin, total phenols, and ascorbic acid. Other cultivars presented also individual properties such as high phenolic compounds were studied and interesting juice concentrate percentage content (Swra hanar cultivar) and the highest arils percentage and high amounts of fructose, sucrose, glucose, and ascorbic the acid in juice and juice concentrate content (Kaua hanar cultivar) and highest juice percentage (Wonderful cultivar). Thus, this work will help pomegranate producers in selecting the extreme appropriate cultivar depending on its final utilize, especially being convenient for fresh consumption or juice concentrate.


2021 ◽  
Vol 11 (15) ◽  
pp. 7152
Author(s):  
Ying Zhang ◽  
Qian-Jin Zhu ◽  
Shuai Gao ◽  
Shuang Liu ◽  
Long-Hai Li ◽  
...  

Straw fiber seedling pots are a promising substitute for plastic seedling pots. The mixing mode of straw fiber affects the mechanical properties of the raw material membrane of the seedling pot. To explore the processing technology of making the raw material membrane of the seedling pot with two kinds of plant fibers in a layered manner, the optimal combination of the process parameters of the raw material membrane of the seedling pot without additives in the production process was studied experimentally. Response surface methodology (RSM) was used to analyze the parameters (beating degree of unbleached softwood kraft pulp fiber, beating degree of wheat straw fiber, wheat straw fiber quality percentage content, and film grammage) with regard to the dry tensile index and Z-direction tensile index of the seedling pot body. The optimal process parameter combination with a certain dry tensile index and Z-direction tensile index of seedling pot raw material was obtained by using four factors and five levels of a quadratic regression orthogonal rotation center combination design parameter optimization experiment. The optimal technical parameters were optimized as wheat straw fiber quality percentage content 70%, film grammage 70 g/m2, unbleached softwood kraft pulp fiber beating degree 47–48 °SR, and wheat straw fiber beating degree 65–75 °SR. With the optimal conditions, the dry tensile index of the seedling bowl raw material film was between 21 and 22 N·(m·g−1), and the Z-direction tensile index was greater than 2.1 N·(m·g−1). Using wheat straw fibers and unbleached sulfite wood pulp fibers as raw materials for seedling pots, the raw material membrane of the seedling pots was made in a layered manner. The experimental study proved this feasibility. With this mixing process of raw materials, the straw fiber-based plant fiber seedling pot would meet the demands of a crop nursery after adding chemical additives. The research results provide a theoretical basis and technical support for the manufacture of the raw material membrane of the seedling pot body.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1474
Author(s):  
María José Beriain ◽  
María T. Murillo-Arbizu ◽  
Kizkitza Insausti ◽  
Francisco C. Ibañez ◽  
Christine Leick Cord ◽  
...  

The physicochemical and sensory differences between the PGI-Certified Ternera de Navarra (CTNA) (Spanish origin) and Certified Angus Beef (CAB) (US origin) were assessed in Spain and the USA. To characterize the carcasses, the ribeye areas (REAs), and marbling levels were assessed in both testing places. Twenty striploins per certified beef program were used as study samples. For sensory analysis, the striploins were vacuum packaged and aged for 7 days at 4 °C and 85% RH in each corresponding laboratory. Thereafter, the samples were half cut and frozen. One of the halves was shipped to the other counterpart-testing place. The fat and moisture percentage content, Warner Bratzler Shear Force (WBSF), and total and soluble collagen were tested for all the samples. The CAB carcasses had smaller REAs (p < 0.0001) and exhibited higher marbling levels (p < 0.0001). The CAB striploins had a higher fat content (p < 0.0001) and required lower WBSF (p < 0.05) than the CTNA samples. Trained panelists rated the CAB samples as juicer (p < 0.001), more tender/less tough (p < 0.0001), and more flavorful (p < 0.0001) than the CTNA counterparts. This study shows that beef from both countries had medium-high tenderness, juiciness, and beef flavor scores and very low off-flavor scores. Relevant differences found between the ratings assigned by the Spanish and the US panelists suggest training differences, or difficulties encountered in using the appropriate terminology for defining each sensory attribute. Furthermore, the lack of product knowledge (i.e., consumption habits) may have been another reason for such differences, despite the blind sensory evaluation.


Author(s):  
Dominika Matuszek ◽  
Karol Bierczyński ◽  
Andżelika Jędrysiak ◽  
Angelika Kraszewska

The article presents the results of homogeneity assessments for selected food mixes based on computer image analysis. The study was conducted on müsli and condiment mixes standardly available on the consumer market. A total of 40 different ready-for-use products were analysed. Collected samples from three package of each product were placed in a special chamber and then photographed. Photographs were then subjected to computer image analysis to acquire information on the percentage content of individual components. Homogeneity assessment was based on the contents of a selected component called tracer and the coefficient of variation (CV). Lower CV values (3.02–27.31%) and thus better homogeneity was observed for condiment mixes as compared to müsli mixes (3.57–59.15%). Fourteen of twenty condiment mixes had adequate (acceptable at CV ≤ 10%) mixing degree. For the müsli, only six of the tested mixes had appropriate homogeneity. The presented results are a preliminary to developing an image-based methodology for determining the uniformity of granular dry food mixes.


2021 ◽  
Vol 45 (3) ◽  
pp. 394-398
Author(s):  
A.V. Demin ◽  
E.N. Sechak ◽  
S.P. Prisyazhnyuk

The article presents results of the development and research of a hyperspectral imaging spectrometer for analyzing borehole fluids in real operating conditions in the spectral range from 0.35 microns to 2.1 microns. A mathematical model and an algorithm for identifying the borehole fluid by composition and percentage content based on the results of hyperspectral image analysis are developed.


2021 ◽  
Vol 16 (2) ◽  
pp. 153-162
Author(s):  
P. A. Idowu ◽  
E. O. Shonubi

Background: Ciprofloxacin, a widely used antimicrobial agent, is available in Nigeria in various tablet and injectable dosage forms. In this era of fake and substandard drugs, it is important to be sure of the quality and antimicrobial potency of ciprofloxacin injectables imported and sold in Nigeria.Objectives: This study is aimed at evaluating and comparing the antibacterial efficacy of five different brands of ciprofloxacin infusion available in Nigeria against clinical bacterial isolates.Method: Ultraviolet-visible (UV-VIS) spectroscopy was used to determine the percentage content of active pharmaceutical ingredient in each brand, while antibacterial activities were compared against five bacterial strains including: Escherichia coli (E), Klebsiella pneumoniae (K), Pseudomonas aeruginosa (Ps), Proteus mirabilis (Pr), Staphylococcus aureus (St) and Salmonella typhi (Sa). Minimum inhibitory concentrations (MICs) and the minimum bactericidal concentration (MBCs) were determined by broth dilution method. Statistical analysis of the results obtained was done by ANOVA.Result: The percentage content of all the five brands of ciprofloxacin injection was not less than the specification (95-105%) of the British Pharmacopoeia, BP (2009). The susceptibility test showed that 16 out of 30 (53.3%) isolates were multidrug resistant. Ciprofloxacin was active on most of the clinical isolates which justify its wide use in treating infections in Nigeria; however, resistance to ciprofloxacin is increasing.Conclusion: Comparing the different brands, there was slight variation but no significant difference (p> 0.05) in their antibacterial activity (p= 0.96, 0.999 for sensitivity at 10μg/ml and MIC respectively). Keywords: Ciprofloxacin brands, Fake drugs, Physicochemical analysis, Antibacterial, Antimicrobial resistance


2021 ◽  
Vol 2 (1) ◽  
pp. 20-25
Author(s):  
F.M. Yushau ◽  
◽  
S. Awwalu ◽  
A. Musa

Background: Metformin tablets are oral anti hyperglycaemic agents that are used as the first line agent in the management of type 2 diabetes mellitus. The proliferation of many brands of metformin tablets in the market has led to availability of different types; some of which may be substandard or counterfeit. Thus, the need to determine the quality of the various brands marketed in Zaria. Objective: To compare the quality of different brands of metformin tablets that are available in Zaria using British pharmacopoeia standards. Method: Seven brands of metformin tablet (500 mg) were randomly sampled from various community pharmacies within Zaria and analysed with respect to identification, weight variation, friability, disintegration time, dissolution and drug content assay using Pharmacopoeial standards. Results: Except for the dissolution and assay tests, the results of all the other parameters for the various brands were within the Pharmacopoeial limits. The percentage content of metformin in brand 2 was 89.90 % which is outside the official range (95 – 105 %). Furthermore, only 70.61, 75.34 and 70.58 % of metformin dissolved from brands 2, 4 and 7 respectively, after 30 minutes of the dissolution test. Conclusion: It can be concluded that of the seven brands evaluated, only four brands are interchangeable with each other and can be substitutes of each other.


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