Substrate properties as controlling parameters in attached algal cultivation

Imaging fluorescence spectroscopy proves to be a fast and sensitive method for measuring the thickness of thin coatings in the manufacturing industry. This encouraged us to systematically study, theoretically and experimentally, parameters that influence the fluorescence of thin layers. We analyzed the fluorescence signal as a function of the scattering and reflectance properties of the sample substrate. In addition, we investigated effects of the layer properties on fluorescence emission. A ray-tracing software is used to describe the influence of these parameters on the fluorescence emission of thin layers. Experiments using a custom-made system for imaging fluorescence analysis verify the simulations. This work shows a factor five variation of fluorescence intensity as a function of the reflectance of the sample substrate. Simulations show variations by a factor of up to eight for samples with different surface roughness. Results on tilted samples indicate a significant increase of the detected fluorescence signal, for fluorescent droplets on reflective substrates, if illuminated and coaxially observed at angles greater than 25°. These findings are of utmost relevance for all applications which utilize the fluorescence emission to quantify thin layers. These applications range from in-line lubricant monitoring in press plants to monitoring of functional coatings in medical technology and the detection of filmic contaminations.

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Advanced Greenhouse Horticulture: New Technologies and Cultivation Practices

Horticulturae ◽

10.3390/horticulturae7010001 ◽

2020 ◽

Vol 7 (1) ◽

pp. 1

Author(s):

Athanasios Koukounaras

Keyword(s):

New Technologies ◽

Light Emitting Diode ◽

Dye Sensitized Solar Cells ◽

Original Research ◽

Brewery Wastewater ◽

Cultivation Practices ◽

Substrate Properties ◽

Greenhouse Horticulture ◽

Negative Impacts ◽

The Impact

Greenhouse horticulture is one of the most intensive agricultural systems, with the advantages of environmental parameter control (temperature, light, etc.), higher efficiency of resource utilization (water, fertilizers, etc.) and the use of advanced technologies (hydroponics, automation, etc.) for higher productivity, earliness, stability of production and better quality. On the other hand, climate change and the application of high inputs without suitable management could have negative impacts on the expansion of the greenhouse horticulture sector. This special issue gathers twelve papers: three reviews and nine of original research. There is one review that focuses on irrigation of greenhouse crops, while a second surveys the effects of biochar on container substrate properties and plant growth. A third review examines the impact of light quality on plant–microbe interactions, especially non-phototrophic organisms. The research papers report both the use of new technologies as well as advanced cultivation practices. In particular, new technologies are presented such as dye-sensitized solar cells for the glass cover of a greenhouse, automation for water and nitrogen deficit stress detection in soilless tomato crops based on spectral indices, light-emitting diode (LED) lighting and gibberellic acid supplementation on potted ornamentals, the integration of brewery wastewater treatment through anaerobic digestion with substrate-based soilless agriculture, and application of diatomaceous earth as a silica supplement on potted ornamentals. Research studies about cultivation practices are presented comparing different systems (organic-conventional, aeroponic-nutrient film technique (NFT)-substrate culture), quantitative criteria for determining the quality of grafted seedlings, and of wild species as alternative crops for cultivation.

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Reaction of human chymase with reactive site variants of alpha 1-antichymotrypsin. Modulation of inhibitor versus substrate properties.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)49508-2 ◽

1993 ◽

Vol 268 (31) ◽

pp. 23626-23633 ◽

Cited By ~ 1

Author(s):

N.M. Schechter ◽

L.M. Jordan ◽

A.M. James ◽

B.S. Cooperman ◽

Z.M. Wang ◽

...

Keyword(s):

Reactive Site ◽

Substrate Properties

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Resolving few-layer antimonene/graphene heterostructures

npj 2D Materials and Applications ◽

10.1038/s41699-021-00230-3 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Tushar Gupta ◽

Kenan Elibol ◽

Stefan Hummel ◽

Michael Stöger-Pollach ◽

Clemens Mangler ◽

...

Keyword(s):

Scanning Transmission Electron Microscopy ◽

Structural Diversity ◽

Growth Behavior ◽

Oxide Formation ◽

Rich Phase ◽

One Dimensional ◽

Transmission Electron ◽

Scanning Transmission ◽

Substrate Properties ◽

The Rich

AbstractTwo-dimensional (2D) antimony (Sb, “antimonene”) is of interest in electronics and batteries. Sb however exhibits a large allotropic structural diversity, which is also influenced by its support. Thus, Sb heterostructure formation is key in 2D Sb integration. Particularly, 2D Sb/graphene interfaces are important. We thus study here few-layered 2D Sb/graphene heterostructures with atomic resolution (scanning) transmission electron microscopy. We find two Sb morphologies to coexist: first, a 2D morphology of layered β-Sb with β-Sb(001)||graphene(001) texture. Second, one-dimensional Sb nanowires which can be matched to β-Sb[2-21]⊥graphene(001) and are closely related to cubic Sb(001)||graphene(001). Importantly, both Sb morphologies show rotational van-der-Waals epitaxy with graphene. Both are resilient against oxidation, although superficial Sb-oxide formation merits consideration, including epitaxial Sb2O3(111)/β-Sb(001) heterostructures. Exact Sb growth behavior depends on processing and substrate properties including, notably, the support underneath the graphene. Our work elucidates the rich phase and epitaxy landscape in 2D Sb and 2D Sb/graphene heterostructures.

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Enzymatic Synthesis and Characterization of Different Families of Chitooligosaccharides and Their Bioactive Properties

Applied Sciences ◽

10.3390/app11073212 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3212

Author(s):

Noa Miguez ◽

Peter Kidibule ◽

Paloma Santos-Moriano ◽

Antonio O. Ballesteros ◽

Maria Fernandez-Lobato ◽

...

Keyword(s):

High Performance ◽

Chemical Characterization ◽

Amperometric Detection ◽

Anion Exchange Chromatography ◽

Exchange Chromatography ◽

Enzymatic Production ◽

Bioactive Properties ◽

Substrate Properties ◽

Chitin Hydrolysis

Chitooligosaccharides (COS) are homo- or hetero-oligomers of D-glucosamine (GlcN) and N-acetyl-D-glucosamine (GlcNAc) that can be obtained by chitosan or chitin hydrolysis. Their enzymatic production is preferred over other methodologies (physical, chemical, etc.) due to the mild conditions required, the fewer amounts of waste and its efficiency to control product composition. By properly selecting the enzyme (chitinase, chitosanase or nonspecific enzymes) and the substrate properties (degree of deacetylation, molecular weight, etc.), it is possible to direct the synthesis towards any of the three COS types: fully acetylated (faCOS), partially acetylated (paCOS) and fully deacetylated (fdCOS). In this article, we review the main strategies to steer the COS production towards a specific group. The chemical characterization of COS by advanced techniques, e.g., high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and MALDI-TOF mass spectrometry, is critical for structure–function studies. The scaling of processes to synthesize specific COS mixtures is difficult due to the low solubility of chitin/chitosan, the heterogeneity of the reaction mixtures, and high amounts of salts. Enzyme immobilization can help to minimize such hurdles. The main bioactive properties of COS are herein reviewed. Finally, the anti-inflammatory activity of three COS mixtures was assayed in murine macrophages after stimulation with lipopolysaccharides.

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Hidden diversity in the oomycete genus Olpidiopsis is a potential hazard to red algal cultivation and conservation worldwide

European Journal of Phycology ◽

10.1080/09670262.2019.1664769 ◽

2019 ◽

Vol 55 (2) ◽

pp. 162-171

Author(s):

Yacine Badis ◽

Tatyana A. Klochkova ◽

Janina Brakel ◽

Paola Arce ◽

Martin Ostrowski ◽

...

Keyword(s):

Potential Hazard ◽

Red Algal ◽

Algal Cultivation

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Influence of thermal substrate properties on the damage threshold of UV coatings

10.1117/12.344387 ◽

1999 ◽

Author(s):

Holger Blaschke ◽

Sven Martin ◽

Andreas Morak ◽

Ch. Koenigsdoerffer ◽

M. Roth ◽

...

Keyword(s):

Damage Threshold ◽

Substrate Properties

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Integration of Waste Valorization for Sustainable Production of Chemicals and Materials via Algal Cultivation

Topics in Current Chemistry ◽

10.1007/s41061-017-0175-y ◽

2017 ◽

Vol 375 (6) ◽

Cited By ~ 5

Author(s):

Yong Chen ◽

Li-ping Sun ◽

Zhi-hui Liu ◽

Greg Martin ◽

Zheng Sun

Keyword(s):

Sustainable Production ◽

Waste Valorization ◽

Algal Cultivation

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Enzymatic synthesis and phosphorolysis of 4(2)-thioxo- and 6(5)-azapyrimidine nucleosides by E. coli nucleoside phosphorylases

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.12.254 ◽

2016 ◽

Vol 12 ◽

pp. 2588-2601 ◽

Cited By ~ 3

Author(s):

Vladimir A Stepchenko ◽

Anatoly I Miroshnikov ◽

Frank Seela ◽

Igor A Mikhailopulo

Keyword(s):

Purine Nucleoside Phosphorylase ◽

Reaction Conditions ◽

E Coli ◽

No Formation ◽

Structural Peculiarities ◽

Substrate Properties ◽

Nucleoside Phosphorylases ◽

Derivatives Of

The trans-2-deoxyribosylation of 4-thiouracil (4SUra) and 2-thiouracil (2SUra), as well as 6-azauracil, 6-azathymine and 6-aza-2-thiothymine was studied using dG and E. coli purine nucleoside phosphorylase (PNP) for the in situ generation of 2-deoxy-α-D-ribofuranose-1-phosphate (dRib-1P) followed by its coupling with the bases catalyzed by either E. coli thymidine (TP) or uridine (UP) phosphorylases. 4SUra revealed satisfactory substrate activity for UP and, unexpectedly, complete inertness for TP; no formation of 2’-deoxy-2-thiouridine (2SUd) was observed under analogous reaction conditions in the presence of UP and TP. On the contrary, 2SU, 2SUd, 4STd and 2STd are good substrates for both UP and TP; moreover, 2SU, 4STd and 2’-deoxy-5-azacytidine (Decitabine) are substrates for PNP and the phosphorolysis of the latter is reversible. Condensation of 2SUra and 5-azacytosine with dRib-1P (Ba salt) catalyzed by the accordant UP and PNP in Tris∙HCl buffer gave 2SUd and 2’-deoxy-5-azacytidine in 27% and 15% yields, respectively. 6-Azauracil and 6-azathymine showed good substrate properties for both TP and UP, whereas only TP recognizes 2-thio-6-azathymine as a substrate. 5-Phenyl and 5-tert-butyl derivatives of 6-azauracil and its 2-thioxo derivative were tested as substrates for UP and TP, and only 5-phenyl- and 5-tert-butyl-6-azauracils displayed very low substrate activity. The role of structural peculiarities and electronic properties in the substrate recognition by E. coli nucleoside phosphorylases is discussed.

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