In Vitro Sensitivity Research Concerning Some Microorganisms at Hydroxyquinoline and Cupric Derivatives Deposited onto Hydroxyapatite

ABSTRACT Introduction: The preparations based on hydroxyquinoline, in various combinations, are used in medicine, being shown to have an inhibitory effect against bacteria, molds, fungi, parasites, and viruses, but also having other beneficial effects mentioned in other medical conditions (anti-cancer, anti-degenerative, anti-inflammatory). Aims: In vitro susceptibility testing of microorganisms: bacteria (Gram positive and Gram negative), yeast (Candida spp.,) and unicellular algae (Prototheca spp.) at the preparations based on hydroxyquinoline (HQ) and its cupric derivatives deposited on hydroxyapatite (HAP). Materials and methods: There were tested microbial strains of the following genera: Escherichia, Staphylococcus, Micrococcus, Bacillus, Candida, and Prototheca. The tested products (developed in the Laboratory for Nanobiomaterials Synthesis, Center of Physical Chemistry, Faculty of Chemistry and Chemical Engineering, UBB Cluj-Napoca) were developed in three versions: 1) HQ-Cu2+-HAP1; 2) HQ-Cu2+-HAP2; and 3) NHQ-Cu2+-HAP2, where NHQ stands for nitro hydroxyquinoline. Determination of the inhibitory effect was conducted by diffusion technique in nutrient agar, according to CLSI 2013 standards, with necessary adaptations for testing of products made in the form of suspensions. Results: Following interpretation, it was found that the inhibition zones, arising from the antimicrobial effect of the tested products showed variability in size, depending on the test product and the microbial strain: Escherichia coli (8-10 mm), Staphylococcus sp. (17.6 - 23.2 mm), Micrococcus spp. (24.4 - 27.6 mm), Bacillus spp. (14.0 - 16.0 mm), Candida spp. (20.4 - 25.2 mm), Prototheca spp. (20.8 - 30.0 mm). From the three tested products, the best efficacy was found at the product no. 3 (NHQ - Cu2+ - HAP2), followed by no. 1 (HQ- Cu2+-HAP1) and no. 2 (HQ-Cu2+-HAP2). Conclusions: The inhibitory effect was bactericidal, manifested more intensively against Gram-positive bacteria, yeasts, and prototheca. Such products, prepared in the form of suspensions, may have practical application in the prevention and treatment of skin or hooves disorders. No resistance phenomena are recorded. Keywords: copper, hydroxyapatite, hydroxyquinoline, microorganisms, sensitivity

Morphological and Cultural Characterization of some Strains of Unicellular Algae of the Genus Prototheca Sampled from Mastitic Cow Milk

Prototheca is a unicellular, achlorophillous, ubiquitary and saprophytic alga spread in the surrounding environment mostly in vastly damp locations in the presence of the organic matters. This is deemed to be pathogenic to a low degree, taking immediate advantage of the environment and triggering diseases at a time when the immunological capability of defense of the organisms is low or, when favorable factors come about. Prototheca is capable to induce disease in man as well as in several other animal species. Twenty strains of Prototheca sp, were sampled from cows with mastitis. The strains are characterized morphologically and developmentally on various culture media: glucose media (broth and agar), blood agar, potato medium, glucose medium of various pH values, medium containing antibiotics, Mac Conkey agar, Smith Baskerville medium (without antibiotics), and engine-oil medium. Growth took place within conditions of aerobic at 37 C and the culture became visible within 36-48 hours. On liquid media there has been noticed that the medium keeps settled and the tube bottom shelters granular drags, that lend to slight homogenization. On solid media the colonies become visible within 36-48 hours. By continuing to maintain them at room temperature, they increase in size. First, they are small, irregular in shape resembling ice crystals reflecting shiny irisations. With lapse of time, they increase in size reaching 3-5 mm, displaying pale-white colour. They also increase in height and the surface takes a mulberry or cauliflower shape. Morphological assessment was carried out on wet smear in Lol solution or in thinned staining solutions (methylene blue, malachite green, Congo red or fuchsine), allowing for good differentiation in the inner structures. The prevailig shape of Prototheca is that of an egg, seldom round or, that of a kidney with variation in size between 9.5/10.5?m up to 27.5/30.4?m. With some cells 6 to 8 endospores were noticed. Based on morphological and cultural characters there was set down that the strains under surveillance belonged to the species of Prototheca zopfii.</span