scholarly journals Apiin-induction of β-apiosidase production by Aspergillus sp. strains

2020 ◽  
Vol 13 (1) ◽  
pp. 72-76
Author(s):  
Klaudia Karkeszová ◽  
Viera Illeová ◽  
Peter Kis ◽  
Vladimír Mastihuba ◽  
Milan Polakovič
Keyword(s):  
Aspergillus Niger ◽  
Minor Component ◽  
Enzyme Preparations ◽  
High Productivity ◽  
Agric Food ◽  
Volatile Terpenes ◽  
Aspergillus Sp ◽  
A Minor ◽  
Hydrolysis Of ◽  
Enzyme Source

Abstractβ-Apiosidase is a rare glycosidase applied in winemaking for flavour enhancement. This enzyme is involved in the release of volatile terpenes by hydrolysis of their odourless glycosidic precursors. It is found as a minor component in commercial pectinase/cellulase preparations. Microbial production of β-apiosidase by two Aspergillus sp. strains was investigated. Apiin-induced production of this extracellular glycosidase was confirmed only during the cultivation of Aspergillus niger CBS 554.65 but the high productivity value reported in the work of Dupin et al. (1992) J. Agric. Food Chem. 40(10): 1886—1891 could not be reproduced. The achieved productivity was by far not satisfactory considering the apiin cost. Commercial enzyme preparations with β-apiosidase side-activity thus remain a better alternative as the enzyme source for biocatalytic applications.

scholarly journals Use of a Hydrolytic Procedure and Spectrometric Methods in the Structure Elucidation of a Thiocarbonyl Analogue of Sildenafil Detected as an Adulterant in an Over-the-Counter Herbal Aphrodisiac

2009 ◽  
Vol 92 (5) ◽  
pp. 1336-1342 ◽  
Author(s):  
John C Reepmeyer ◽  
D Andr d'Avignon
Keyword(s):  
Dietary Supplement ◽  
Carbonyl Group ◽  
Minor Component ◽  
Pyrimidine Ring ◽  
Over The Counter ◽  
Methyl Group ◽  
Nmr Spectrometry ◽  
A Minor ◽  
Hydrolysis Of ◽  
Hydroxyethyl Group

Abstract A sildenafil-related compound was detected in an herbal dietary supplement marketed as an aphrodisiac. The compound was identified as an analogue of sildenafil in which the carbonyl group in the pyrimidine ring of sildenafil was substituted with a thiocarbonyl group, and the methyl group on the piperazine ring was substituted with a hydroxyethyl group. Based on this structure, the compound was named thiohydroxyhomosildenafil. The structure of the compound was established using HPLC/MS, UV spectrometry, electrospray ionization-MS/MS, NMR spectrometry, and a hydrolytic process. One key product of hydrolysis was 1-(2-hydroxyethyl)-piperazine; the identification of this product defined the amine portion of the compound. Another key product of hydrolysis was hydroxyhomosildenafil, generated by hydrolysis of the thiocarbonyl group to a carbonyl group (C S C O). Hydroxyhomosildenafil was detected as a minor component in the dietary supplement.

Preparation of N-Acetylchitooligosaccharides by Enzymatic Hydrolysis of Chitosans

2010 ◽  
Vol 160-162 ◽  
pp. 1358-1361
Author(s):  
Hong Zhu ◽  
Zhi Hui Qiu ◽  
Qiong Hou
Keyword(s):  
Enzymatic Hydrolysis ◽  
Aspergillus Niger ◽  
Acetic Anhydride ◽  
Production Process ◽  
Chemical Reactions ◽  
Enzyme Preparations ◽  
High Yields ◽  
Hydrolysis Of

An economical production process of higher N-acetylchitooligosaccharides [(GlcNAc)n, n=5~7 ] was developed with enzymatic and chemical reactions in this study. (GlcNAc)n were prepared selectively and efficiently by hydrolysis of chitosans with cheap enzyme preparations including cellulase TV, cellulosin A.C and hemicellulase, followed by N-acetylation with acetic anhydride. Higher (GlcNAc)n could be obtained in high yields by using cellulosin A.C and hemicellulase, which are originated from Aspergillus niger.

scholarly journals Produksi kultur rendam jamur Aspergillus niger dan Aspergillus oryzae ITBCCL sebagai sumber enzim untuk produksi bioetanol dari singkong

2018 ◽  
Vol 5 (1) ◽  
pp. 350
Author(s):  
Siti Maemunah ◽  
Achmad Ali S
Keyword(s):  
Enzymatic Hydrolysis ◽  
Aspergillus Niger ◽  
Aspergillus Oryzae ◽  
Raw Material ◽  
Starchy Material ◽  
Pre Treatment ◽  
Liquefaction Process ◽  
Aspergillus Sp ◽  
Hydrolysis Of ◽  
Fuel Source

Bio ethanol is a very attractive fuel source for communities or even countries that wish to be self-sustainable and not reliant on foreign resources. A variety of feedstock materials may be used to produce ethanol, such as glucose or starchy material (cassava, corn, etc.), by preparing it with a hydrolysis pre-treatment to form glucose. The enzymatic hydrolysis of starch requires at least two different enzymes such as α-amylase for liquefaction process and maltase for saccharification process. The main objective of this research is to produce sub-merged culture enzyme from Aspergillus sp that contained α-amylase and maltase enzymes in sufficient quantity to convert starch which is contained in cassava powder to form glucose. Aspergillus niger CCL 74 ITB and Aspergillus oryzae CCL ITB were cultivated in sub-merged culture. The main raw material of the medium had been varied between vinase from molasse and cake from peanut. Sub-merged culture from Aspergillus niger CCL74 ITB in the vinase medium gave higher a-amylase and maltase activities, compare to sub­ merged culture from A. oryzae CCL ITB. Using vinase from molasse gave higher enzymes yield than using medium from peanut cake.Keywords: α-amylase and Maltase, Sub-merged culture of Aspergillus niger. Aspergillus oryzae AbstrakBahan bakar hayati seperti bioetanol merupakan bahan bakar ramah lingkungan yang potensial dalam mengurangi impor BBM Indonesia. Rute utama pembuatan bioetanol adalah viafermentasi bahan berkarbohidrat. Bahan berkarbohidrat yang potensial dikembangkan di Indonesia dalam produksi bioetanol adalah singkong. Proses konversi pati dalam singkong menjadi etanol biasanya dilakukan melalui proses enzimatik yaitu proses likuefaksi oleh enzim α-amilase, proses sakarifikasi oleh enzim maltase dan fermentasi. Tujuan penelitian ini adalah mendapatkan kultur jamur Aspergillus sp. yang menghasilkan enzim α-amilase dan maltase dalam kuantitas memadai yang akan digunakan sebagai sumber enzim penghidrolisis pati dalam singkong. Jenis jamur yang digunakan Aspergillus niger CCL 74 ITB dan Aspergillus oryzae CCL ITB. Bahan baku utama medium divariasikan antara vinase dan bungkil kacang tanah. Kultur Aspergillus niger CCL74 ITB memberikan aktivitas a-amilase dan maltase yang lebih tinggi dibandingkan dengan kultur Aspergillus oryzae CCL ITB. Penggunaan vinase memberikan hasil yang lebih baik dibandingkan dengan medium bungkil kacang tanah dalam produksi kedua enzim.Kata Kunci: Enzim α-amilase, Glukoamilase, Aspergillus niger.  Aspergillus oryzae

scholarly journals Galactosamine in walls of slow-growing mycobacteria

1997 ◽  
Vol 327 (2) ◽  
pp. 519-525 ◽  
Author(s):  
Philip DRAPER ◽  
Kay-Hooi KHOO ◽  
Delphi CHATTERJEE ◽  
Anne DELL ◽  
R. Howard MORRIS
Keyword(s):  
Fast Atom Bombardment ◽  
Minor Component ◽  
Amino Sugar ◽  
Human Pathogens ◽  
Partial Acid Hydrolysis ◽  
A Minor ◽  
State Examination ◽  
Slow Growing ◽  
Hydrolysis Of ◽  
Fast Atom Bombardment Ms

Galactosamine was found consistently as a minor component of the envelope of five species of slow-growing mycobacteria, including all the major human pathogens, but not three rapid-growing species. The amino sugar was a component of the arabinogalactan of the cell wall skeleton, and occurred at the level of about one residue per arabinogalactan chain. Its amino group was in the free, un-N-acetylated state. Examination of oligosaccharides released by partial acid hydrolysis of arabinogalactan by fast atom bombardment-MS and gas chromatography-MS identified a series of oligoarabinans, each possessing one GalN unit, linked to position 2 of arabinose. It is proposed that the GalN residues occur as stub branches of 1 → 5-linked arabinose chains in the arabinogalactan. Possible functions of GalN are discussed.

SATOUMI APPROACH FOR REALIZING SUSTAINABLE COASTAL USE IN A RIASTYPE BAY: A CASE OF SHIZUGAWA BAY IN SANRIKU COAST HIT BY THE HUGE TSUNAMI ON 11 MARCH 2011

2017 ◽  
Author(s):  
Teruhisa Komatsu ◽  
Teruhisa Komatsu ◽  
Shuji Sasa ◽  
Shuji Sasa ◽  
Shigeru Montani ◽  
...  
Keyword(s):  
Local Governments ◽  
Minor Element ◽  
Coupling Model ◽  
Sanriku Coast ◽  
High Productivity ◽  
Biological Coupling ◽  
Miyagi Prefecture ◽  
Human Use ◽  
A Minor ◽  
Aquaculture Facilities

Rias-type bays are one of the most common coasts in Japan where aquacultures have been active due to sheltered geological shape with a deep bottom. The huge tsunami hit Sanriku Coast consisting of open rias-type bays near the epicenter facing Pacific Ocean on 11 March 2011. For recovering Sanriku Coast, it is important to include sustainability in its program. Satoumi is defined as the human use and management of coastal seas for high productivity while maintaining high biodiversity. Therefore, we proposed Satoumi approach to an open rias-type bay, Shizugawa Bay, in southern Sanriku Coast. We conducted scientific researches on mapping of coastal habitats and aquaculture facilities, hydrography, and material flows of nutrients, a minor element (Fe) and organic matters in the bay including those from the rivers and from the offshore waters. At the same time, Committee for Shizugawa Bay Management of Fishermen’s Cooperative of Miyagi Prefecture decided to decrease in aquaculture facilities for sustainable development of aquaculture. Based on these data, a physical-biological coupling model was used for calculating the number of aquaculture facilities that are suitable not only for yields but also for environments. These researches were established on strong collaborations among a fishermen’s’ cooperative, local governments and scientists. Results of this practice may help to realize sustainable coastal use of a rias-type bay.

Protonation effects on dynamic flux properties of aqueous metal complexes

2009 ◽  
Vol 74 (10) ◽  
pp. 1543-1557 ◽  
Author(s):  
Herman P. Van Leeuwen ◽  
Raewyn M. Town
Keyword(s):  
Complex Formation ◽  
Metal Ion ◽  
Good Description ◽  
Minor Component ◽  
Outer Sphere ◽  
Metal Species ◽  
Central Metal ◽  
Inner Sphere ◽  
A Minor ◽  
Protonated Ligand

The degree of (de)protonation of aqueous metal species has significant consequences for the kinetics of complex formation/dissociation. All protonated forms of both the ligand and the hydrated central metal ion contribute to the rate of complex formation to an extent weighted by the pertaining outer-sphere stabilities. Likewise, the lifetime of the uncomplexed metal is determined by all the various protonated ligand species. Therefore, the interfacial reaction layer thickness, μ, and the ensuing kinetic flux, Jkin, are more involved than in the conventional case. All inner-sphere complexes contribute to the overall rate of dissociation, as weighted by their respective rate constants for dissociation, kd. The presence of inner-sphere deprotonated H2O, or of outer-sphere protonated ligand, generally has a great impact on kd of the inner-sphere complex. Consequently, the overall flux can be dominated by a species that is a minor component of the bulk speciation. The concepts are shown to provide a good description of experimental stripping chronopotentiometric data for several protonated metal–ligand systems.

scholarly journals Improvement of Enzymatic Saccharification of Cellulose-Containing Raw Materials Using Aspergillus niger

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1360
Author(s):  
Ekaterina Budenkova ◽  
Stanislav Sukhikh ◽  
Svetlana Ivanova ◽  
Olga Babich ◽  
Vyacheslav Dolganyuk ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Aspergillus Niger ◽  
Filter Paper ◽  
Raw Materials ◽  
Enzymatic Saccharification ◽  
Wood Chip ◽  
Cellulase Activity ◽  
Wood Chips ◽  
Acid Pretreatment ◽  
Hydrolysis Of

Enzymatic hydrolysis of cellulose-containing raw materials, using Aspergillus niger, were studied. Filter paper, secondary cellulose-containing or starch-containing raw materials, miscanthus cellulose after alkaline or acid pretreatment, and wood chip cellulose, were used as substrates. The study focused on a wild A. niger strain, treated, or not (control), by ultraviolet (UV) irradiations for 45, 60, or 120 min (UV45, UV60, or UV120), or by UV irradiation for 120 min followed by a chemical treatment with NaN3 + ItBr for 30 min or 80 min (UV120 + CH30 or UV120 + CH80). A mixture of all the A. niger strains (MIX) was also tested. A citrate buffer, at 50 mM, wasthe most suitable for enzymatic hydrolysis. As the UV exposure time increased to 2 h, the cellulase activity of the surviving culturewas increased (r = 0.706; p < 0.05). The enzymatic activities of the obtained strains, towards miscanthus cellulose, wood chips, and filter paper, were inferior to those obtained with commercial enzymes (8.6 versus 9.1 IU), in some cases. Under stationary hydrolysis at 37 °C, pH = 4.7, the enzymatic activity of A. niger UV120 + CH30 was 24.9 IU. The enzymatic hydrolysis of secondary raw materials, using treated A. niger strains, was themost effective at 37 °C. Similarly, the most effective treatment of miscanthus cellulose and wood chips occurred at 50 °C. The maximum conversion of cellulose to glucose was observed using miscanthus cellulose (with alkaline pretreatment), and the minimum conversion was observed when using wood chips. The greatest value of cellulase activity was evidenced in the starch-containing raw materials, indicating that A. niger can ferment not only through cellulase activity, but also via an amylolytic one.

Petrography and provenance of the Marambio Group, Vega Island, Antarctica

1994 ◽  
Vol 6 (4) ◽  
pp. 517-527 ◽  
Author(s):  
Duncan Pirrie
Keyword(s):  
Late Cretaceous ◽  
Sedimentary Rocks ◽  
Clay Mineralogy ◽  
Minor Component ◽  
Source Area ◽  
Low Grade ◽  
Western Margin ◽  
Sediment Input ◽  
A Minor ◽  
Sandstone Petrography

Late Cretaceous sedimentary rocks assigned to the Santa Marta (Herbert Sound Member) and López de Bertodano (Cape Lamb and Sandwich Bluff members) formations of the Marambio Group, crop out on Cape Lamb, Vega Island. Although previous studies have recognized that these sedimentary rocks were derived from the northern Antarctic Peninsula region, the work presented here allows the provenance and palaeogeographical evolution of the region to be described in detail. On the basis of both sandstone petrography and clay mineralogy, the Herbert Sound and Cape Lamb members reflect sediment input from a low relief source area, with sand grade sediment sourced from low grade metasediments, and clay grade sediment ultimately derived from the weathering of an andesitic source area. In contrast, the Sandwich Bluff Member reflects a switch to a predominantly andesitic volcaniclastic source. However, this sediment was largely derived from older volcanic suites due to renewed source area uplift, with only a minor component from coeval volcanism. Regional uplift of both the arc terrane and the western margin of the James Ross Basin was likely during the Maastrichtian.

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