scholarly journals Characterization of Glucomannan Extracted from Fresh Porang Tubers Using Ethanol Technical Grade

Molekul ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 1
Author(s):  
Nurlela Nurlela ◽  
Nina Ariesta ◽  
Dwi Sutari Laksono ◽  
Edi Santosa ◽  
Tjahja Muhandri
Keyword(s):  
Extraction Methods ◽  
Second Step ◽  
Drying Process ◽  
Direct Extraction ◽  
Technical Grade ◽  
Sem Image ◽  
Concentration Method ◽  
Fixed Concentration ◽  
Low Levels

Glucomannan is a polysaccharide consisting of β-1.4-linked D-mannose and D-glucose monomers, which have many benefits especially in the food and pharmaceutical industry. It has been widely reported that one of the main sources of glucomannan is porang tuber (Amorphophallus muelleri Blume). Generally, glucomannan extracted or purified from porang flour. However, the drying process causes other compounds than glucomannan stick strongly, resulting low levels of glucomannan. This study was to obtain glucomannan extract in an easy, effective, and inexpensive method, by direct extraction from fresh porang tubers using ethanol technical grade. We performed two extraction methods. The first is a fixed concentration method, the sample was repeatedly extracted using 50% ethanol (FC50) and 96% ethanol (FC96) 3 times, respectively. The second is a multilevel concentration method, the sample was repeatedly extracted using ethanol 60% (first step), 80% (second step), and 96% (third step), one replication each step. The highest glucomannan content (66.56%) was obtained by a multilevel concentration method. Moisture, lipid, protein, crude fiber, calcium oxalate level significantly reduce to 13.58%, 0.07%, 4.03%, 4.95%, 0.56% respectively. FTIR spectra confirmed the presence of functional groups (O-H, C=O, C-O, C-H), that compose the glucomannan compound. SEM image showed that the granules form of glucomannan were round and oval, began to change its phase from amorphous to crystalline, related to XRD data. The results showed that the direct extraction from fresh porang tuber using ethanol technical grade with a multilevel concentration method was an effective method to extract the glucomannan

scholarly journals Glandular Secretions of Ants (Hymenoptera: Formicidae): A Review on Extraction, Chemical Characterization and Antibiotic Potential

Sociobiology ◽  
2020 ◽  
Vol 67 (1) ◽  
pp. 13
Author(s):  
Carin Guarda ◽  
Junir Antonio Lutinski
Keyword(s):  
Scientific Literature ◽  
Chemical Characterization ◽  
Antimicrobial Effect ◽  
Extraction Methods ◽  
Immune Defense ◽  
Direct Extraction ◽  
Ant Behavior ◽  
Antifungal Potential ◽  
Microclimatic Conditions

Ants live under ideal microclimatic conditions for the development of microorganisms. As mechanisms to ensure the health of the colony and as a defense strategy, these insects developed exocrine glands that work in the production of antibiotics (chemical defense) and in the immune defense of the colony. This study aimed to describe the state-of-the-art on extraction methods, chemical characterization and the antibiotic potential of glandular secretions of ants. This is a review of the scientific literature between 1989 and 2017. A total of 52 articles were selected. These addressed the behavior, chemical characterization, the antimicrobial effect and evaluated methods of extraction. The most investigated genera are Atta, Acromyrmexand Crematogaster. The glands most reported in the articles involving extraction of secretions were Dufour, mandibular and metapleural. The most reported methods of extraction were gland maceration and extraction with (organic) solvents and direct extraction of the gland. Most studies evaluated secretions with respect to ant behavior. There is a paucityin the literature about the chemical characterization of most glandular secretions of ants, as well as for most taxa. The same deficiency is observed with regard to prospecting the antibiotic and antifungal potential of these secretions. for most taxa. The same deficiency is observed with regard to prospecting the antibiotic and antifungal potential of these secretions.

Characterization of dissolved organic matter (DOM) extracted from soils by hot water percolation (HWP)

2010 ◽  
Vol 59 (1) ◽  
pp. 99-108 ◽  
Author(s):  
M. Takács ◽  
Gy. Füleky
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Natural Organic Matter ◽  
Extraction Methods ◽  
Soil Samples ◽  
Hot Water ◽  
Soil Extracts ◽  
Water Percolation ◽  
Soil Humic Acid

The Hot Water Percolation (HWP) technique for preparing soil extracts has several advantages: it is easily carried out, fast, and several parameters can be measured from the same solution. The object of this study was to examine the possible use of HWP extracts for the characterization of soil organic matter. The HPLC-SEC chromatograms, UV-VIS and fluorescence properties of the HWP extracts were studied and the results were compared with those of the International Humic Substances Society (IHSS) Soil Humic Acid (HA), IHSS Soil Fulvic Acid (FA) and IHSS Suwannee Natural Organic Matter (NOM) standards as well as their HA counterparts isolated by traditional extraction methods from the original soil samples. The DOM of the HWP solution is probably a mixture of organic materials, which have some characteristics similar to the Soil FA fractions and NOM. The HWP extracted organic material can be studied and characterized using simple techniques, like UV-VIS and fluorescence spectroscopy.

scholarly journals A Tracer Study on sCO2 Corrosion with Multiple Oxygen-Bearing Impurities

2021 ◽  
Author(s):  
Juho Lehmusto ◽  
Anton V. Ievlev ◽  
Ercan Cakmak ◽  
James R. Keiser ◽  
Bruce A. Pint
Keyword(s):  
Production Systems ◽  
Power Production ◽  
Model Alloy ◽  
Tracer Study ◽  
Protective Oxide ◽  
Scale Thickness ◽  
Low Levels ◽  
High Temperature Reactions ◽  
Ti Addition

AbstractSeveral modern power production systems utilize supercritical CO2 (sCO2), which can contain O2 and H2O as impurities. These impurities may degrade the compatibility of structural alloys through accelerated oxidation. However, it remains unclear which of these impurities plays a bigger role in high-temperature reactions taking place in sCO2. In this study, various model and commercial Fe‐ and Ni‐based alloys were exposed in 300 bar sCO2 at 750 °C to low levels (50 ppm) of O2 and H2O for 1,000 h. 18O-enriched water was used to enable the identification of the oxygen source in the post-exposure characterization of the samples. However, oxygen from the water did not accumulate in the scale, which consisted of Cr2O3 in the cases where a protective oxide formed. A 2wt.% Ti addition to a Ni-22%Cr model alloy resulted in the formation of thicker oxides in sCO2, while a 1wt.% Al addition reduced the scale thickness. A synergistic effect of both Al and Ti additions resulted in an even thicker oxide than what was formed solely by Ti, similar to observations for Ni-based alloy 282.

scholarly journals Nanotechnology in Roman Opaque Red Glass from the 2nd Century AD. Archaeometric Investigation in Red Sectilia from the Decoration of the Lucius Verus Villa in Rome

Heritage ◽  
2019 ◽  
Vol 2 (3) ◽  
pp. 2597-2611 ◽  
Author(s):  
Mario Bandiera ◽  
Patrice Lehuédé ◽  
Marco Verità ◽  
Luis Alves ◽  
Isabelle Biron ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Chemical Characterization ◽  
Second Step ◽  
Colorimetric Analysis ◽  
Historical Sources ◽  
Pixe Analysis ◽  
X Ray ◽  
Colorimetric Measurements ◽  
Shed Light

This work aims to characterise the chemical composition of Roman opaque red glass sectilia dated to the 2nd century A.D and to shed light on Roman glassmaking production of different shades of red, from red to reddish-brown. Due to the lack of technical historical sources for this period many questions about technological aspects still remain. In this project a multi-disciplinary approach is in progress to investigate the red glass sectilia with several red hues from the Imperial Villa of Lucius Verus (161–169 A.D.) in Rome. First, colorimetric measurements were taken to identify the various red hues. The second step was chemical characterization of the samples and the identification of crystalline colouring phases. Particle Induced X-Ray Emission (PIXE) analysis was used to investigate the chemical composition of these glass samples, while the crystalline phases were identified by Raman Spectroscopy and Scanning Electrons Microscope with Energy Dispersive X-ray Spectrometry (SEM-EDS). Using SEM-EDS nanoparticles were detected as a colouring agent, the chemical composition and the morphology of which has been studied in depth. This information has been compared with the colorimetric analysis to establish any correlation with the different colour hues.

scholarly journals Optimization of extraction methods for characterization of phenolic compounds in apricot fruit (Prunus armeniaca)

2019 ◽  
Vol 10 (10) ◽  
pp. 6492-6502
Author(s):  
Lisard Iglesias-Carres ◽  
Anna Mas-Capdevila ◽  
Francisca Isabel Bravo ◽  
Cinta Bladé ◽  
Anna Arola-Arnal ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Extraction Methods ◽  
Prunus Armeniaca ◽  
Health Promoting

Fruits are rich in phenolic compounds with health-promoting activities.

scholarly journals Characterization of Trypsin Inhibitor in Florunner Peanut Seeds (Arachis hypogaea L.)1

1988 ◽  
Vol 15 (2) ◽  
pp. 81-84 ◽  
Author(s):  
E. M. Ahmed ◽  
J. A. Applewhite
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Arachis Hypogaea ◽  
Trypsin Inhibitor ◽  
Low Molecular Weight ◽  
Arachis Hypogaea L ◽  
Amino Acid Profiles ◽  
Low Levels

Abstract Florunner peanut seeds contained five trypsin isoinhibitors. Amino acid profiles of the trypsin inhibitors fraction showed high levels of aspartic acid, half-cystine and serine and low levels of histidine and tyrosine. The molecular weight of the inhibitor was 8.3 KDa. The presence of multiforms of this inhibitor, its low molecular weight and the high amount of half-cystine indicate that peanut trypsin inhibitor is of the Bowman-Birk type.

Headnote Prediction Using Machine Learning

2021 ◽  
Vol 18 (5) ◽  
Author(s):  
Sarmad Mahar ◽  
Sahar Zafar ◽  
Kamran Nishat
Keyword(s):  
Machine Learning ◽  
Feature Extraction ◽  
Active Learning ◽  
Text Classification ◽  
Extraction Methods ◽  
Text Summarization ◽  
Training Data ◽  
Second Step ◽  
Support Vector ◽  
Classification Algorithms

Headnotes are the precise explanation and summary of legal points in an issued judgment. Law journals hire experienced lawyers to write these headnotes. These headnotes help the reader quickly determine the issue discussed in the case. Headnotes comprise two parts. The first part comprises the topic discussed in the judgment, and the second part contains a summary of that judgment. In this thesis, we design, develop and evaluate headnote prediction using machine learning, without involving human involvement. We divided this task into a two steps process. In the first step, we predict law points used in the judgment by using text classification algorithms. The second step generates a summary of the judgment using text summarization techniques. To achieve this task, we created a Databank by extracting data from different law sources in Pakistan. We labelled training data generated based on Pakistan law websites. We tested different feature extraction methods on judiciary data to improve our system. Using these feature extraction methods, we developed a dictionary of terminology for ease of reference and utility. Our approach achieves 65% accuracy by using Linear Support Vector Classification with tri-gram and without stemmer. Using active learning our system can continuously improve the accuracy with the increased labelled examples provided by the users of the system.

scholarly journals Assessing high-throughput environmental DNA extraction methods for meta-barcode characterization of aquatic microbial communities

2018 ◽  
Vol 17 (1) ◽  
pp. 37-49 ◽  
Author(s):  
Abdolrazagh Hashemi Shahraki ◽  
Subba Rao Chaganti ◽  
Daniel Heath
Keyword(s):  
Microbial Community ◽  
Microbial Communities ◽  
High Throughput ◽  
Environmentally Friendly ◽  
Environmental Dna ◽  
Magnetic Bead ◽  
Extraction Methods ◽  
Environmental Research ◽  
Rrna Gene

Abstract The characterization of microbial community dynamics using genomic methods is rapidly expanding, impacting many fields including medical, ecological, and environmental research and applications. One of the biggest challenges for such studies is the isolation of environmental DNA (eDNA) from a variety of samples, diverse microbes, and widely variable community compositions. The current study developed environmentally friendly, user safe, economical, and high throughput eDNA extraction methods for mixed aquatic microbial communities and tested them using 16 s rRNA gene meta-barcoding. Five different lysis buffers including (1) cetyltrimethylammonium bromide (CTAB), (2) digestion buffer (DB), (3) guanidinium isothiocyanate (GITC), (4) sucrose lysis (SL), and (5) SL-CTAB, coupled with four different purification methods: (1) phenol-chloroform-isoamyl alcohol (PCI), (2) magnetic Bead-Robotic, (3) magnetic Bead-Manual, and (4) membrane-filtration were tested for their efficacy in extracting eDNA from recreational freshwater samples. Results indicated that the CTAB-PCI and SL-Bead-Robotic methods yielded the highest genomic eDNA concentrations and succeeded in detecting the core microbial community including the rare microbes. However, our study recommends the SL-Bead-Robotic eDNA extraction protocol because this method is safe, environmentally friendly, rapid, high-throughput and inexpensive.

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