ABSTRACT
Unfortunately, M. M. Vrvic name has been published incorrectly in the original publication as M. M. Vrivic, corrected name appears in this erratum.
ABSTRACT
Twenty different streptomycete isolates were obtained from soils of southeast Serbia. Five isolates identified as Streptomyces hygroscopicus (SH100, SH101, SH102, SH103, and SH104) showed strong activity against Botrytis cinerea, a parasite found in domestic vines. These isolates were extensively studied for their in vitro antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria, yeasts and fungi, and also antiviral activity against Herpes simplex. The results indicated that the obtained isolates were highly active against Botrytis cinerea, Candida albicans, and Herpes simplex, with an inhibition zone of approximately 31 mm. The structure of the bioactive components was determined using elemental analysis, as well as UV/VIS, FTIR, and TLC.
Subject(s)
Streptomyces/physiology , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Antiparasitic Agents/isolation & purification , Antiparasitic Agents/pharmacology , Antiviral Agents/isolation & purification , Antiviral Agents/pharmacology , Botrytis/drug effects , Botrytis/growth & development , Candida albicans/drug effects , Candida albicans/growth & development , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/growth & development , Gram-Positive Bacteria/drug effects , Gram-Positive Bacteria/growth & development , Simplexvirus/drug effects , Simplexvirus/growth & development , Soil Microbiology , Streptomyces/classification , Streptomyces/isolation & purificationABSTRACT
The sunflower oil methanolysis was studied in a stirred reactor at different agitation speeds. The measurements of drop size, drop size distribution and the conversion degree demonstrate the effects of the agitation speed in both non-reaction (methanol/sunflower oil) and reaction (methanol/KOH/sunflower oil) systems. Drop size distributions were found to become narrower and shift to smaller sizes with increasing agitation speed as well as with the progress of the methanolysis reaction at a constant agitation speed. During the methanolysis reaction, the Sauter-mean drop diameter stays constant in the initial slow reaction region, rapidly decreases during the fast reaction period and finally reaches the equilibrium level. Due to the fact that the interfacial area increases, one can conclude that the rate of reaction occurring at the interface will also be enhanced progressively. The "autocatalytic" behavior of the methanolysis reaction is explained by this "self-enhancement" of the interfacial area, due to intensive drop breakage process.
Subject(s)
Methanol/chemistry , Plant Oils/chemistry , Emulsions/chemistry , Hydroxides/chemistry , Potassium Compounds/chemistry , Sunflower OilABSTRACT
The ultrasonic extraction (UE) of oil from the seeds of a semi-oriental tobacco (Nicotiana tabacum L.) plant strain by using n-hexane and petroleum ether was studied at different temperatures and seeds-to-solvent ratios. The oil yield depended on the seed comminution, the extraction temperature, the seeds-to-solvent ratio and the type of solvent. The oil yield was much higher if the seeds were ground before extraction. The oil yield increased with increasing the extraction temperature and with decreasing the seeds-to-solvent ratio. n-Hexane was somewhat more efficient in the oil extraction than petroleum ether. In recovering the tobacco seed oil (TSO), the UE was less efficient than the Soxhlet extraction. The advantage of the UE was a relatively high oil yield at 25 degrees C in a shorter time. The kinetics of UE of TSO was described using the model of unsteady diffusion through plant material.
Subject(s)
Nicotiana/chemistry , Plant Oils/isolation & purification , Ultrasonics , Seeds/chemistry , Solvents/chemistryABSTRACT
The specific growth rate, the maximum specific dextransucrase production rate and the maximum dextransucrase yield during the dextransucrase fermentation byLeuconostoc mesenteroides were all unaffected by both the pH of the culture medium, maintained at 5.5 or 6.7, and the mode of pH control, by adding NaOH or K2HPO4.