scholarly journals The quantitative metabolome is shaped by abiotic constraints

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Amir Akbari ◽  
James T. Yurkovich ◽  
Daniel C. Zielinski ◽  
Bernhard O. Palsson
Keyword(s):  
Isotope Labeling ◽  
Theoretical Biology ◽  
Acid Stress ◽  
Living Systems ◽  
Charge Imbalance ◽  
Fundamental Part ◽  
Physico Chemical ◽  
Transcriptional Regulatory ◽  
Key Characteristics ◽  
Abiotic Constraints

AbstractLiving systems formed and evolved under constraints that govern their interactions with the inorganic world. These interactions are definable using basic physico-chemical principles. Here, we formulate a comprehensive set of ten governing abiotic constraints that define possible quantitative metabolomes. We apply these constraints to a metabolic network of Escherichia coli that represents 90% of its metabolome. We show that the quantitative metabolomes allowed by the abiotic constraints are consistent with metabolomic and isotope-labeling data. We find that: (i) abiotic constraints drive the evolution of high-affinity phosphate transporters; (ii) Charge-, hydrogen- and magnesium-related constraints underlie transcriptional regulatory responses to osmotic stress; and (iii) hydrogen-ion and charge imbalance underlie transcriptional regulatory responses to acid stress. Thus, quantifying the constraints that the inorganic world imposes on living systems provides insights into their key characteristics, helps understand the outcomes of evolutionary adaptation, and should be considered as a fundamental part of theoretical biology and for understanding the constraints on evolution.

scholarly journals The quantitative metabolome is shaped by abiotic constraints

2020 ◽  
Author(s):  
Amir Akbari ◽  
James T. Yurkovich ◽  
Daniel C. Zielinski ◽  
Bernhard O. Palsson
Keyword(s):  
Isotope Labeling ◽  
Theoretical Biology ◽  
Acid Stress ◽  
Living Systems ◽  
Transport Systems ◽  
Charge Imbalance ◽  
Physico Chemical ◽  
Transcriptional Regulatory ◽  
Key Characteristics ◽  
Abiotic Constraints

AbstractLiving systems formed and evolved under governing constraints that characterize their interactions with the inorganic world. These interactions are definable using basic physico-chemical principles. Here, we formulate a comprehensive set of ten governing abiotic constraints that define possible quantitative metabolomes. We apply these constraints to a metabolic network of Escherichia coli that represents 90% of its metabolome. We show that the quantitative metabolomes allowed by the abiotic constraints are consistent with metabolomic and isotope labeling data. We find that: (i) Network-wide characterization of charge-, proton- and magnesium-related constraints shape transcriptional regulatory responses to osmotic stress; (ii) Proton and charge imbalance underlie transcriptional regulatory responses to acid stress; (iii) Abiotic constraints drive the evolution of transport systems, such as high-affinity phosphate transporters. Thus, quantifying the constraints that the inorganic world imposes on living systems provides insights into their key characteristics, helps understand the outcomes of evolutionary adaptation, and should be considered as a fundamental part of theoretical biology and for understanding the constraints on evolution.

scholarly journals Ohmic Heating in the Food Industry: Developments in Concepts and Applications during 2013–2020

2021 ◽  
Vol 11 (6) ◽  
pp. 2507
Author(s):  
Zina T. Alkanan ◽  
Ammar B. Altemimi ◽  
Asaad R. S. Al-Hilphy ◽  
Dennis G. Watson ◽  
Anubhav Pratap-Singh
Keyword(s):  
Energy Consumption ◽  
Ohmic Heating ◽  
Bioactive Compound ◽  
Heating Time ◽  
Microbial Inactivation ◽  
Conventional Heating ◽  
Food Ingredients ◽  
Physico Chemical ◽  
Key Characteristics ◽  
Comparable Performance

Various technologies have been evaluated as alternatives to conventional heating for pasteurization and sterilization of foods. Ohmic heating of food products, achieved by passage of an alternating current through food, has emerged as a potential technology with comparable performance and several advantages. Ohmic heating works faster and consumes less energy compared to conventional heating. Key characteristics of ohmic heating are homogeneity of heating, shorter heating time, low energy consumption, and improved product quality and food safety. Energy consumption of ohmic heating was measured as 4.6–5.3 times lower than traditional heating. Many food processes, including pasteurization, roasting, boiling, cooking, drying, sterilization, peeling, microbiological inhibition, and recovery of polyphenol and antioxidants have employed ohmic heating. Herein, we review the theoretical basis for ohmic treatment of food and the interaction of ohmic technology with food ingredients. Recent work in the last seven years on the effect of ohmic heating on food sensory properties, bioactive compound levels, microbial inactivation, and physico-chemical changes are summarized as a convenient reference for researchers and food scientists and engineers.

scholarly journals Coating Matters: Review on Colloidal Stability of Nanoparticles with Biocompatible Coatings in Biological Media, Living Cells and Organisms

2018 ◽  
Vol 25 (35) ◽  
pp. 4553-4586 ◽  
Author(s):  
Jonas Schubert ◽  
Munish Chanana
Keyword(s):  
Colloidal Stability ◽  
Biological Fluids ◽  
Chemical Properties ◽  
Coating Material ◽  
Living Systems ◽  
Biological Media ◽  
Coating Materials ◽  
Physico Chemical ◽  
Environment Temperature ◽  
To Come

Within the last two decades, the field of nanomedicine has not developed as successfully as has widely been hoped for. The main reason for this is the immense complexity of the biological systems, including the physico-chemical properties of the biological fluids as well as the biochemistry and the physiology of living systems. The nanoparticles’ physicochemical properties are also highly important. These differ profoundly from those of freshly synthesized particles when applied in biological/living systems as recent research in this field reveals. The physico-chemical properties of nanoparticles are predefined by their structural and functional design (core and coating material) and are highly affected by their interaction with the environment (temperature, pH, salt, proteins, cells). Since the coating material is the first part of the particle to come in contact with the environment, it does not only provide biocompatibility, but also defines the behavior (e.g. colloidal stability) and the fate (degradation, excretion, accumulation) of nanoparticles in the living systems. Hence, the coating matters, particularly for a nanoparticle system for biomedical applications, which has to fulfill its task in the complex environment of biological fluids, cells and organisms. In this review, we evaluate the performance of different coating materials for nanoparticles concerning their ability to provide colloidal stability in biological media and living systems.

scholarly journals Pharmacognostic and Analytical Profile of Leaves of Erythroxylum Moonii Hochr. – An Ethno-Medicinal Plant

2021 ◽  
Vol 12 (2) ◽  
pp. 353-359
Author(s):  
Perera P A N G ◽  
Acharya Rabinarayan ◽  
Pandya P ◽  
Harisha C R ◽  
Shukla V J
Keyword(s):  
Test Sample ◽  
Phytochemical Analysis ◽  
Standard Procedures ◽  
Physico Chemical ◽  
Key Characteristics ◽  
Microscopic Evaluation ◽  
Microscopic Features ◽  
Acuminate Apex ◽  
Analytical Standards ◽  
Light Green

Erythroxylum moonii Hochr. is a shrub or small tree in family Erythroxylaceae and folklore claims report the use of its leaves in the treatment of helminthiasis. Aim: Hence, present study aims to evaluate the pharmacognostic and analytical characters including HPTLC of its leaves. Methods: E. moonii fresh and powdered leaves were explored for the macroscopic and microscopic features along with their physico-chemical, phytochemical properties and HPTLC following standard procedures. Results: The leaf of E. moonii is simple, alternate, petiolate, stipulate, elliptic and lanceolate with obtusely caudate-acuminate apex, acute base and entire margins. Fresh leaf is light green, slight astringent with characteristic odour and smooth texture. Powdered dry leaves were light green, slight astringent with aromatic odour and coarse, fibrous texture. Microscopic evaluation revealed the presence of simple, bilobed and stellate trichomes (with and without lignification), rosette, rhomboidal, prismatic and cluster crystals, paracytic stomata and starch grains as key characteristics both in fresh leaves and powdered leaves. Obtained values for loss on drying, total ash, acid insoluble ash, pH, water and methanol soluble extractive were 10.44±0.31%, 2.2±0.67%, 0.93±0.06%, 5, 7.63±0.57% and 6.44±0.38% respectively. Qualitative phytochemical analysis suggested the presence of carbohydrates, steroids, glycosides, saponins, alkaloids, tannins and flavonoids in the test sample. HPTLC study revealed 17 and 11 peaks at short (254nm) and long (366nm) ultraviolet consecutively. Conclusion: Obtained results can be used to establish pharmacognostic and analytical standards of leaves of E. moonii which can serve as an important source to determine the quality, purity and strength of the powdered drug. 

Nanostructures of Water Molecules in Iteratively Filtered Water

2011 ◽  
Vol 495 ◽  
pp. 37-40 ◽  
Author(s):  
Vittorio Elia ◽  
Elena Napoli
Keyword(s):  
Electrical Conductivity ◽  
Chemical Properties ◽  
Dissipative Structures ◽  
Living Systems ◽  
Water Molecules ◽  
Distilled Water ◽  
Main Ingredient ◽  
Structure Of Water ◽  
Physico Chemical

This work presents some experimental results on the variation of the physico-chemical properties of pure, twice distilled water, when subject to a procedure of iterative filtrations through Pyrex glass filters (Büchner funnels). The study involves the determination of electrical conductivity. After the filtrations, electrical conductivity increases three times. Part of those increases, about 10-30%, is to be attributed to impurities released by the glass filters. The hypothesis is that the remaining 70-90% of the increases comes from variations in the super-molecular structure of water. The iterative filtration procedure involves a flux of energy and material in an open system. The energy flux is partially dissipated as heat permitting the formation of “dissipative structures”. Water, the main ingredient of living systems, exhibits an extraordinary auto-organization potentiality triggered by several kinds of perturbations, including mechanical ones.

Biological Recursion and Digital Systems: Conceptual Tools for Analysing Man-Machine Interaction

2020 ◽  
Vol 37 (5) ◽  
pp. 27-49
Author(s):  
Paolo Totaro ◽  
Domenico Ninno
Keyword(s):  
Living System ◽  
Digital Systems ◽  
Living Systems ◽  
Common Denominator ◽  
Theory Of Computation ◽  
Computational Results ◽  
Order Relations ◽  
Physico Chemical ◽  
The Many ◽  
Machine Interaction

The theory of numbers, the theory of computation and well-known biological and neurological studies on cognition and consciousness all indicate the concept of recursion as their common denominator. Mathematical recursion owes its meaning and properties to a dual relationship between its results, which always constitute a sequence, and the operator that generated them, which is instead invariant. This article proposes that this duality in recursion originates from the duality between the biological homeostatic equilibrium in living systems and the adaptive physico-chemical changes required to sustain such equilibria. Such duality gives order and meaning to the experiences of a living system. One of the many implications of this innovative perspective is that this duality can decouple computational results from our intuitive order relations, and that this can cause a rarefaction of the capacity of digital systems to convey communication and favour adaptation to the environment.

Nuclear magnetic resonance spectroscopy of living systems: applications in comparative physiology

1996 ◽  
Vol 76 (3) ◽  
pp. 799-837 ◽  
Author(s):  
G. Van Den Thillart ◽  
A. Van Waarde
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Acid Stress ◽  
Living Systems ◽  
Biological Research ◽  
Resonance Spectroscopy ◽  
Comparative Physiology ◽  
Nuclear Magnetic

The most attractive feature of nuclear magnetic resonance spectroscopy (MRS) is the noninvasive and nondestructive measurement of chemical compounds in intact tissues. MRS already has many applications in comparative physiology, usually based on observation of 31P, since levels of phosphorus compounds indicate tissue energy status and are changed during exercise, fatigue, recovery, hypometabolism, anesthesia, hypoxia, hypercapnia, and osmotic and acid stress. Nuclei other than 31P may also be monitored, such as 1H, 13C, 15N, 19F, or 23Na, and applied in biological research. Particularly, 13C-MRS is interesting because it allows the analysis of metabolic pathways in living systems. Applications of MRS in comparative physiology and biochemistry are comprehensively discussed in this review. The main focus is on anaerobic metabolism during hypoxia, ischemia, and exercise. Species as widely different as slime molds, nematodes, frogs, turtles, and ducks have been studied by 31P-MRS. It is not surprising that striking species differences do occur, but many similarities are also observed. Unique is the occurrence of six different phosphagens with different values of Gibbs free energy in polychete worms The presence of a particular phosphagen may be related to the average oxygen tension within the tissues. Phosphagens and their kinases are also discussed in relation to hypercapnia and acid stress. Other topics discussed in this paper are enzyme kinetics, anesthetics, development and growth, parasitism, and the detection of previously unknown compounds.

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