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The use of antimicrobial agents is responsible for the emergence and spread of antibiotic resistant bacteria. Nevertheless, multiresistant bacteria have been found in animals that have never been exposed to antimicrobial agents. Wild animals that are carriers of methicillin-resistant organisms represent a hazard since they can transmit their bacteria to other animals and to humans. In the hunting season 2009/2010 nasal swabs of 98 red deer and 109 wild boars were examined for the presence of methicillin-sensitive and methicillin-resistant staphylococci. From each wild boar methicillin-susceptible staphylococci (Staphylococcus aureus in 28% and Staphylococcus spp. in 72% of the animals) were isolated. In red deer the detection rate of Staphylococcus (S.) aureus and methicillin-susceptible staphylococci was 49% and 17%, respectively. The occurrence of S. aureus was significantly higher (p < 0.05) in red deer than in wild boars. Methicillin-resistant staphylococci were not found. However, in one third of the red deer, methicillin-resistant bacteria of the genus Enterococcus spp. and Bacillus spp. were isolated. The results of the present study indicate that wildlife, especially red deer are an important reservoir for S. aureus and that the upper respiratory tract of red deer is regularly colonised with methicillin-resistant bacteria such as Bacillus spp. and Enterococcus spp. Primarily, commensal bacteria are harmless to human health, however, red deer may be a reservoir for antibiotic-resistant bacteria.

The H2O2-low-temperature-plasma-sterilization (STERRAD 100) works with a temperature below 50 degrees C (140 degrees F). This system is appliable for thermostabile materials as well as for thermolabile materials. The efficancy of this new system is shown by a biological test with Bacillus pumilus spores. 5 typical ophthalmic surgical instruments were contaminated. After sterilization the numerical reduction of the microorganisms had to be at least 6 log levels. Corrosion caused by hydrogene peroxide was excluded after exposing steal with a high quantity of this substrate. Electromicroscopy analysations of the surfaces of stainless steal after LTP, steam sterilization and hot-air sterilization are compared. Options and limitations of this new sterilization technique are discussed. A newly developed operating system with a complete instrumental box (OP-Set) will be introduced.

Microbiological examinations of mouth-cleaning, cooling, and turbine spray waters from various types of dental units showed different degrees of water contamination. The detection of Pseudomonas aeruginosa, because of the classification of this organism as a "problem germ", indicates the necessity for a more critical analysis of water used in stomatology including the elimination of possible sources of contamination.

This paper describes investigations on disinfection of germ carriers, contaminated with an alcoholic suspension of Bacillus cereus or Bacillus subtilis. Result of disinfection is compared with that of an additional heat treatment (80 degrees C, 60 min) after disinfection. Besides Formalin, Tegodor forte (Th. Goldschmidt, Essen) and P 3 oxonia active (Henkel KG, Düsseldorf) are tested with different concentration and duration. Heat activation was possible with all three disinfectants. For illuminating the conditions of activation, circumstances of heat action after disinfection with formaldehyde-aerosol have been varied. Heat activation in dry air, moist air and distilled water was not successful. Only in Nutrient Broth (Standard I-Bouillon; Merck, Darmstadt) spores were viable again, after activation. Addition of serum as a protective cover had no influence on the result. Consequences of the results on a disinfection method with formaldehyde-aerosol are discussed.

In total 30 nitrogen-fixing, saccharolytic Clostridia and 4 nitrogen-fixing bacilli, all freshly isolated from gleyed soils, were screened for sensitivity to 20 antibiotics. The isolates were compared in their sensitivity with 5 type cultures representing the species Clostridium butyricum, C. saccharobutyricum (2 strains) C. multifermentans and C. sporogenes. Generally speaking, both clostridia and bacilli are sensitive to the same antibiotics (Table 2). In addition, the nitrogen-fixing bacilli belonging to Bacillus polymyxa and B. macerans showed sensitivity to neomycin and kanamycin. Except for the species C. tyrobutyricum, none of the various saccharolytic Clostridium species could be distinguished by differences in sensitivity to antibiotics. Differential methods are given in Table 3.

Three new antibiotics, merulinic acids A, B, and C, have been isolated from fruiting bodies of Merulis tremellosus and Phlebia radiata. They are closely related derivatives of beta-resorcylic and salicylic acid, carrying monounsaturated C17-alkyl side chains in 6-position. The merulinic acids are mixtures of the delta8'-compounds with minor amounts of the corresponding delta10'-, dehydro, and dihydro derivatives, separable only by means of HPLC. delta8'-Merulinic acid A (I) was synthesized via a biomimetic cyclization of a linear precursor. The merulinic acids inhibit a variety of bacteria and are not active against fungi. RNA, DNA, and protein synthesis in Bacillus brevis and Ehrlich carcinoma ascites cells are inhibited shortly after the addition of the antibiotics. Almost complete hemolysis of human erythrocytes is caused by 25 microgram/ml of merulinic acid B and C or by 73 microgram/ml of merulinic acid A.

The sporocidal properties of peracetic acid (PAA) at defined concentrations were characterized by determination of decrease in PAA after addition of D-glucose, human albumin and suspensions of spores; concentration of PAA, which inactivates 10(6)-10(7) spores of Bacillus cereus, B. subtilis, B. megaterium and B. licheniformis within 10-30 min; inactivation constant k, decimal reduction time D and the sporocidal index (mg PAA X min X ml-1) at that concentration. In contrast to albumin, the spore suspension caused relatively little reduction of PAA concentration (less than 5% at the concentrations used). B. cereus, B. subtilis and B. megaterium had similar inactivation rates with k-values in the range of 0.368 and 0.541 min-1, D-values between 4.26 min and 6.26 min at 0.2 mg/ml PAA. B. lichenformis was much more resistant showing a k = 0.345 min-1 and D = 6.66 min at 3.0 mg/ml PAA. The sporocidal index of B. lichenformis was 180 mg X min X ml-1 while the three other species had sporocidal index-values of 7 mg X min X ml-1.

Using the suspension test the action of dibromoisocyanuric acid (DBI) and--for the purpose of a comparison--elemental chlorine and Chloramine-T on three different spore strains at pH 7.0 and room temperature has been investigated. DBI proved to be a desinfecting agent by which at a concentration of 0.01 M positive halogene (= 1.45 g DBI/I) in 15--60 minutes (depending on the spore strain) a reliable kill can be achieved. Although using elemental chlorine shorter kill rates have been obtained (Chloramine-T was without any effect) DBI shows some advantages which also suggest its use in practice. As possible reasons for the differing efficiency of the three investigated substances the equilibrium concentrations of the hydrolysis products (HOCl resp. HOBr) and diffusion effects are discussed.