Aims: This study aims to evaluate the effectiveness of bacteriophages isolated from Klang and Penang, Malaysia against Dickeya chrysanthemi that causes soft rot disease. Methodology and results: Basic characterization such as dextrose test, citrate test, lactose fermentation test and ornithine test were carried out on D. chrysanthemi. Activity of bacteriophages against D. chrysanthemi was evaluated using spot test. Double agar overlay assay was performed to purify and enumerate the quantify of bacteriophages. Bacteriophages were also checked for its effectiveness in controlling soft rot on post-harvested vegetables: potato (Solanum tuberosum), cucumber (Cucumis sativus) and apple (Malus domestica). Results showed that D. chrysanthemi able to utilize citrate and dextrose as the source of energy, which indicated that D. chrysanthemi inclined to choose fruits and vegetables containing citrate and dextrose as the target of attack. Clear zone observed on the bacterial lawn (spot test) indicated the ability of the bacteriophages to infect and lyse D. chrysanthemi. All the bacteriophages studied herein reached the highest concentration on day 3 and were monovalent. Conclusion, significance and impact of study: All the isolated bacteriophages were able to restrain the spreading of soft rot caused by D. chrysanthemi either work alone or as cocktail. This study provides information for the formulation development of bacteriophage against soft rot disease cause by D. chrysanthemi. Furthermore, this study reveals the potential of locally isolated bacteriophages against the D. chrysanthemi and paving the application of phage treatment on agriculture products that are not limited to potatoes, cucumber and apple.

Letters to the EditorOptochin sensidvity of f3-haemolytic streptococci group A Optochin (ethyl hydrocuprein hydrochloride) sensitivity testing is routinely performed by most laboratories for the differentiation of Streptococcus pneumoniae from other streptococci.In our laboratory all streptococci, seen by Gram staining of blood cultures, are tested for sensitivity to optochin. The optochin test results are read after 4-6 h incubation at 36°C, along with other antibiotic sensitivity tests.This procedure was followed on a set of blood cultures from a patient who was subsequently shown to have a 83-haemolytic streptococcus group A infection; however, there was a zone size >14 mm round the optochin disc on the original chocolate agar plate. On overnight testing 18-haemolysis was apparent, but the isolate still gave a zone >14 mm on a fresh chocolate agar plate.We have investigated the phenomenon of optochin sensitive /8-haemolytic streptococci group A and our results are presented. Material