Adina-Elena Segneanu

Bio: Adina-Elena Segneanu is an academic researcher from West University of Timișoara. The author has contributed to research in topics: Secondary metabolite & Serviceability (structure). The author has an hindex of 3, co-authored 10 publications receiving 62 citations.

Organic Compounds FT-IR Spectroscopy

Abstract: General spectral range of electromagnetic radiation with a wavelength greater than 750 nm (i.e. with the number of wavelength below 13000 cm-1) bears the name of the domain infrared (IR). In this field samples absorb electromagnetic radiation due to transitions of vibration of the structure of molecules, molecular transitions in vibrations crystalline network (if the sample is in the solid state of aggregation) or due to transitions of molecular rotation. Subdomain of spectral wavelengths between 2500 50000 nm (respectively the wave numbers 4000 to 200 cm-1) bears the name of the middle infrared domain.

Peptide and Amino Acids Separation and Identification from Natural Products

Abstract: The natural extracts of plants are an important source for the identification of new biologically active compounds with possible applications in the pharmaceutical field. Phytotherapy embraces especially the isolation from herbs, of compounds with unique chemical structures, which are considered to be pharmacologically active. Recent statistics show that, on an annual basis, there are identified over 1500 new compounds from different species of plants, and about one quarter of prescription drugs contain substances of plant origin.

Bioactive Molecules Profile from Natural Compounds

Abstract: Currently, wide world research is focused on sustainable development and the demand for innovative clean technologies, nevertheless natural potential reconsideration could represent a viable solution for the identification and design of new pharmacological agents from renewable resources. The main reason consists of special properties of these natural derivates: immunomodulating activity with continuously perfectible selectiv‐ ity and efficiency. Plants and herb extracts have been used for centuries as traditional medicines, throughout the entire world. Romanian phytotherapy represents practically a very important part of our traditional knowledge and heritage. Therapeutic properties of plant active principles still continue to be the subject of many researches. In this chapter, an overview of plant bioactive molecules from the perspective of modern phytochemis‐ try is presented. A special part is devoted to a very special medicinal plant, Viscum album, in particular identification of amino acids and thionins from mistletoe.

Assessment of the Different Type of Materials Used for Removing Phosphorus from Wastewater

Abstract: Reducing the costs associated with water management, improving water quality and the environment are fundamental requirements of sustainable development. Maintaining the optimal level of phosphorus has a direct impact on water quality and the biological system. Current methods used in tertiary wastewater treatment for phosphorus removal present several disadvantages that influence the final water processing cost. Therefore, it is essential for water quality and food safety to develop ecological, cheap and highly efficient materials. This study reported the first comparative assessment of three different types of materials (magnetic, semiconductors and composite) as environmentally friendly, cheap adsorbents for phosphorus removal from wastewater. Several experiments were done to investigate the influence of adsorbent type, dosage and contact time on the efficiency of the processes. The adsorption process was fast and equilibrium was reached within 150 min. We found that the phosphorus adsorption efficiency on of these materials was higher than the chemical method. The obtained results indicated that specific surface area directly influences the performance of the adsorption process. EDS analysis was used to analyze adsorbents composition and analyze the type and content of elements in the substrate before and after reaction with wastewater.

Artemisia annua Growing Wild in Romania—A Metabolite Profile Approach to Target a Drug Delivery System Based on Magnetite Nanoparticles

Abstract: The metabolites profile of a plant is greatly influenced by geographical factors and the ecological environment. Various studies focused on artemisinin and its derivates for their antiparasitic and antitumoral effects. However, after the isolation and purification stage, their pharmaceutical potential is limited due to their low bioavailability, permeability and lifetime. The antibacterial activity of essential oils has been another topic of interest for many studies on this plant. Nevertheless, only a few studies investigate other metabolites in Artemisia annua. Considering that secondary metabolites act synergistically in a plant, the existence of other metabolites with antitumor and high immunomodulating activity is even more important. Novel nano-carrier systems obtained by loading herbs into magnetic nanoparticles ensures the increase in the antitumor effect, but also, overcoming the barriers related to permeability, localization. This study reported the first complete metabolic profile from wild grown Romanian Artemisia annua. A total of 103 metabolites were identified under mass spectra (MS) positive mode from 13 secondary metabolite categories: amino acids, terpenoids, steroids, coumarins, flavonoids, organic acids, fatty acids, phenolic acids, carbohydrates, glycosides, aldehydes, hydrocarbons, etc. In addition, the biological activity of each class of metabolites was discussed. We further developed a simple and inexpensive nano-carrier system with the intention to capitalize on the beneficial properties of both components. Evaluation of the nano-carrier system’s morpho-structural and magnetic properties was performed.

Observation of Potential Contaminants in Processed Biomass Using Fourier Transform Infrared Spectroscopy

Abstract: With rapidly increased interests in biomass, diverse chemical and biological processes have been applied for biomass utilization Fourier transform infrared (FTIR) analysis has been used for characterizing different types of biomass and their products, including natural and processed biomass During biomass treatments, some solvents and/or catalysts can be retained and contaminate biomass In addition, contaminants can be generated by the decomposition of biomass components Herein, we report FTIR analyses of a series of contaminants, such as various solvents, chemicals, enzymes, and possibly formed degradation by-products in the biomass conversion process along with poplar biomass This information helps to prevent misunderstanding the FTIR analysis results of the processed biomass

Highly Conductive, Stretchable, and Transparent PEDOT:PSS Electrodes Fabricated with Triblock Copolymer Additives and Acid Treatment

Abstract: Here, we report on a highly conductive, stretchable, and transparent electrode of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) fabricated via modification with triblock copolymer, poly(ethylene glycol)–block–poly(propylene glycol)–block–poly(ethylene glycol) (PEO20–PPO70–PEO20, Pluronic P123), and post-treatment with sulfuric acid. The fabricated electrode exhibits high transparency (89%), high electrical conductivity (∼1700 S/cm), and minimal change in resistance (∼4%) under repetitive stretch–release cycles at 40% tensile strain after stabilization. P123 acts as a secondary dopant and plasticizer, resulting in enhanced electrical conductivity and stretchability of PEDOT:PSS. Furthermore, after sulfuric acid post-treatment, P123 helps the electrode to maintain its stretchability. A successful demonstration of the stretchable interconnection was shown by stretching the P123-modified PEDOT:PSS electrodes, which were connected with light-emitting diodes (LEDs) in series. Finally, a st...

The Plant Alkaloids

Abstract: THE alkaloids of plants have long offered a most interesting and attractive, if always difficult, field of research to both chemists and physiologists. The subtle chemistry of the vegetable cell evolves no objects more fascinating to study than these “vegetable alkalis,” as Serturner first termed them; bodies usually of highly complex chemical structure, and often of appalling potency in their physiological effects. Of the problems which they offer, one in particular—that of their chemical constitution-has received a large amount of attention during the last two or three decades, and much progress has been made with it. How much is perhaps scarcely realised until the results are collected and collated, as in the book under notice, in such fashion that a bird's-eye view of the whole field can be readily obtained. Then the reader notes that “alkaloids of unknown constitution” form only one group out of nine, and that group not a remarkably large one; whilst in the case of several members even of this group—for example, the aconites, colchicum, and ergot—knowledge of their structure is beginning to accumulate. The Plant Alkaloids. By Dr. T. A. Henry. Pp. vii + 466. (London: J. and A. Churchill, 1913.) Price 18s. net.