Study of Triple System Calcium Iodide-HMTA-Water

Research relevance: synthesis, physicochemical studies of complexes bioactivity with salts of biometals and organic ligands are of great interest for bio-coordination chemistry. Materials and research methods: isothermal method was used to study heterogeneous equilibria at 25 °C. The concentration limits of compounds existence and the types of their solubility have been established. Research objectives: to investigate compounds of hexamethylenetetramine with salts of biometals with organic ligands in order to reduce toxicity, increase the bioactivity and bioavailability of coordination compounds. Research results: concentration limits of compounds existence and types of their solubility have been established. Conclusions: in obtained complexes, HMTA ligand contains four equivalent electron donor nitrogen atoms.

Protease Produced by Endophytic Fungi: A Systematic Review

The purpose of this systematic review was to identify the available literature of production, purification, and characterization of proteases by endophytic fungi. There are few complete studies that entirely exhibit the production, characterization, and purification of proteases from endophytic fungi. This study followed the PRISMA, and the search was conducted on five databases: PubMed, PMC, Science Direct, Scopus Articles, and Web of Science up until 18 May 2021, with no time or language restrictions. The methodology of the selected studies was evaluated using GRADE. Protease production, optimization, purification, and characterization were the main evaluated outcomes. Of the 5540 initially gathered studies, 15 met the inclusion criteria after a two-step selection process. Only two studies optimized the protease production using statistical design and two reported enzyme purification and characterization. The genus Penicillium and Aspergillus were the most cited among the eleven different genera of endophytic fungi evaluated in the selected articles. Six studies proved the ability of some endophytic fungi to produce fibrinolytic proteases, demonstrating that endophytic fungi can be exploited for the further production of agents used in thrombolytic therapy. However, further characterization and physicochemical studies are required to evaluate the real potential of endophytic fungi as sources of industrial enzymes.

Cyclodextrin-assisted surface-enhanced Raman spectroscopy: a critical review

Numerous approaches have been proposed to overcome the intrinsically low selectivity of surface-enhanced Raman spectroscopy (SERS), and the modification of SERS substrates with diverse recognition molecules is one of such approaches. In contrast to the use of antibodies, aptamers, and molecularly imprinted polymers, application of cyclodextrins (CDs) is still developing with less than 100 papers since 1993. Therefore, the main goal of this review is the critical analysis of all available papers on the use of CDs in SERS analysis, including physicochemical studies of CD complexation and the effect of CD presence on the Raman enhancement. The results of the review reveal that there is controversial information about CD efficiency and further experimental investigations have to be done in order to estimate the real potential of CDs in SERS-based analysis. Graphical abstract

Pharmacognostic and Preliminary Phytochemical Evaluation of Leaf of Syzygium Cumini (L.) Skeels

Syzygium cumini (L.) Skeels (Family: Myricaceae) commonly known as Jamun is a widely used medicinal plant in Ayurveda. In spite of its numerous medicinal attributes, no published work is available on pharmacognostic characterization, physicochemical analysis of its leaves. The measures taken for pharmacognostic characterization were macroscopy, microscopy, powder microscopy, physicochemical evaluation, fluorescence analysis, and preliminary phytochemical screening. The microscopic evaluation showed useful characters for the recognition of leaf of Syzygium cumini (L.) Skeels . Transverse section, showed presence of single layer of wavy epidermal cells with striated cuticle single layer Palisade beneath upper epidermis in lamina region (contains compact elongated cells), Spheraphide in lamina region, collenchyma below the upper epidermis and above the lower epidermis in midrib region, Xylem and phloem in center, Sclerenchyma in between vascular bundle and collenchyma in midrib region. Wavy epidermal cell in the upper epidermis, anisocytic stomata in the lower epidermis, Bordered pitted reticulate vessels, Calcium oxalate crystal sheath in the lamina, fragment of fibers and Spiral vessels were observed in powder microscopy. Physicochemical studies showed total ash (3.1%), acid insoluble ash (0.7%), alcohol soluble extractive values (10.96 %), and water-soluble extractive values (12.32 %). Phytochemical analysis revealed the presence of sugar, lipid, Glycoside, saponins, phenols, flavonoids, tannins, tri-terpenoids and steroids. The study forms the first report on pharmacognostic characters and a physicochemical parameter which could be useful for identification and authentication of the plant.

A Comparative Study of Cerium- and Ytterbium-Based GO/g-C3N4/Fe2O3 Composites for Electrochemical and Photocatalytic Applications

The design of sustainable and efficient materials for efficient energy storage and degradation of environmental pollutants (specifically organic dyes) is a matter of major interest these days. For this purpose, cerium- and ytterbium-based GO/g-C3N4/Fe2O3 composites have been synthesized to explore their properties, especially in charge storage devices such as supercapacitors, and also as photocatalysts for the degradation of carcinogenic dyes from the environment. Physicochemical studies have been carried out using XRD, FTIR, SEM, and BET techniques. Electrochemical techniques (cyclic voltammetry, galvanic charge discharge, and electrochemical impedance spectroscopy) have been employed to measure super-capacitance and EDLC properties. Results show that the gravimetric capacitance calculated from GCD results is 219 Fg−1 for ytterbium- and 169 Fg−1 for cerium-based nanocomposites at the current density of 1 A/g and scan rate of 2 mV/sec. The specific capacitance calculated for the ytterbium-based nanocomposite is 189 Fg−1 as compared to 125 Fg−1 for the cerium-based material. EIS results pointed to an enhanced resistance offered by cerium-based nanocomposites as compared to that of ytterbium, which can be assumed with the difference in particle size, as confirmed from structural studies including XRD. From obtained results, ytterbium oxide-based GO/g-C3N4/Fe2O3 is proven to be a better electro-catalyst as compared to cerium-based nanocomposites. Photocatalytic results are also in agreement with electrochemical results, as the degradation efficiency of ytterbium oxide-based GO/g-C3N4/Fe2O3 (67.11 and 83.50% for rhodamine B and methylene blue dyes) surpasses values observed for cerium-based GO/g-C3N4/Fe2O3 (63.08 and 70.61%).