1.THE BREEDING STUDY BY UV-INDUCING PROTOPLASTS OF LENTINUS EDODES
Zhirong LIANG ; Moping AN ; Zhanyuan TONG
Microbiology 2001;28(2):38-41
The experiment was carried out to inquire about the possibility of strain selection and improvement in Lentinus edodes through protoplast formation and mutagenesis by UV. Mycelial growth rate, yield, and period of fructification of 105 selected regenerants from UV-treated protoplasts have been measured and compared with their parents. Several selected regenerants achieved some better qualities such as higher yield and earlier fruiting. Several repeated cultivations of these regenerants reconfirmed their new capacities. The results indicated that protoplast formation and mutagenesis are the potential methods for strain selection and improvement in edible fungi.
2.0253-2654(2001)02-0012-04 THE PRELIMINARY RESEARCH ABOUT THE REASONS OF BUSTING BAGS OCCASIONALLY DURING SOY STORAGE
Zhiyuan SUN ; Huanshu LIU ; Xiaobin ZHANG
Microbiology 2001;28(2):12-15
Shan Qi soy has busting bags, bacteria sum overproof, continue acidification and other problems occasionally during the storage. It's probably caused by the Lactobacillus continue growth in the soy. We tried expounding the relationship between growth and producing acid when Lactobacillus growing in the thin fermented material.
3.CULTURE CONDITIONS FOR CREATININASE FORMATIONBY PSEUDOMONAS SP. K9510
Jianguo LIU ; Jiyuan KE ; Jinfang WANG ; Gaoxiang LI
Microbiology 2001;28(2):7-11
From air bacteria capable of decomposing creatinine, three single independent strains K9510、K9511 and K9512 have been isolated. The highest creatinine amidohydrolase (EC 3.5.2.10; creatininase) producing strain K9510 was screened out. The strain K9510 was identified as Pseudomonas sp. The results of culture condition for creatininase formation by strain K9510 were obtained as follows: creatinine and creatine were found to be the effective inducers for enzyme formation; the solution of mixed metallic salts could stimulate cell growth and enzyme formation. The suitable medium for creatininase formation was consisted of 0.9% creatinine、 0. 15% yeast extract、 0. 09% malt extract、0.05% NH4C1 and some amount of the solution of mixed metallic salts at pH5. 5. When the bacterium was grown in 250mL conic flask containing 50mL of the medium mentioned above on the rotary shaker(250r/min) at 35℃ for 33 h, about 50 u creatininase was obtained.
4.STUDIES ON HARMFUL MICROBES IN RECIRCULATING WATER SYSTEM OFHEATING PIPELINE IN TAIYUAN
Microbiology 2001;28(2):4-7
The microbial counts, type, as well as relationship between microbial counts and the temperature of water in reticulating water system of heating pipeline in Taiyuan were studied, which the main biofouling harmful microbes included slimeforming heterotrophic bacteria, sulfate reducing bacteria, iron bacteria and fungi, respectively. The results showed that the harmful microbes in water system were lower than that of control guideline during heating period, whereas the microbes were higher than that of control guideline, which would result in biofouling of water tube during non-heating period.
5.THE STUDY OF RELATIONSHIP BETWEEN THE MOVEMENT OF SOILBACTERIAL NUMBER AND ECOLOGICAL FACTORS ON THELEYMUS CHINENSIS GRASSLAND
Microbiology 2001;28(2):1-4
This paper preliminary studied the movement of soil bacterial number, and the relationship with 8 kinds of ecological factors. The result indicated: soil bacterial number only appears a biggest value in one year (2.67×10-7个 individual g-1dry soil). Among 8 kinds of ecological factors, soil water content, temperature, hydrolyted nitrogen, quick acting postossium and active organic matter have straight relationship with siol bacteria, and have negative relationship with soil pH, electric conduct rate, effective phosphorus. The component analysis indicated that soil water content, temperature, electric conduct rate, active organic matter are principal effective factors.
6.BREEDING OF HIGH PRODUCING STRAIN OF LIPASE USING FAST NEUTRON
Yan ZHOU ; Peng ZHANG ; Qingyun MENG ; Tinawei TAN
Microbiology 2001;28(2):81-85
Four methods of breeding high producing strain of Lipase are studied. As a result, the Lipase activity produced by one strain is 93 times as high as befor, and the Lipase activity produced by another is 3.0 times. On these bases, the effects of four methods in breeding are discussed, and the usinng Fast Neutron is more effective method in breeding.
7.A STRAIN OF PSEUDOMONAS AERUGINOSA WITH TEMPERATURE-SENSITIVE FORMATION OF FILAMENTS
Yanguang CONG ; Junkang LIU ; Zetao YYAN ; Qiwang XU
Microbiology 2001;28(2):76-80
A strain of P. Aeruginosa,which was seperated from clinical environment ,shows a special characteristic . It keeps normal short rod shape when cultured at 37℃,however,it forms filament without pyocyanin producing when cultured at 25℃ overnight. The filaments will divide and form short rods,simultaneously,produce pyocyanin when culture time is prolonged to over 72h or culture temperature is raised to 37℃. The preliminary study indicates that this phenomenin has nothing to do with nutritive conditions and could the inbluenced by inoculating density and irradiating with ultraviolet rays The absence of pyocyanin was not the cause of filamentous formation by the test results.
8.STUDIES ON PHARMACOLOGICAL ACTIVITY OF MYCENA DENDROBII
Chunlan WANG ; Xiaomei CHEN ; Shunxing GUO ; Xinmin LIU ; Shaomei SUN ; Shengping WANG ; Weifen SHANG
Microbiology 2001;28(2):73-76
The pharmacological activity of Mycena dendrobii Fan et Guo, a new species of endophytic fungus was studied. It was revealed that the mycelia methanol extracts and the fermentation liquid ethanol extracts of Mycena dendrobii showed anglgesic effect to mice, which have the correlations to that of the traditional Chinese medicine ‘shihu’. The fermentation liquid ethanol extracts of Mycena dendrobii showed excitation effect to central nervous system of mice. Then the effective parts of anglgesic effect was determined.
9.BIODEGRADABLE POLY (D,L-LACTIDE-CO-GLYCOLIC ACID) MICROSPHERESUSED AS ADJUVANT IN DNA IMMUNIZATION OF HEPATITIS B VIRUS S GENE
Fei GONG ; Shude JIANG ; Weidong LI ; Junying CHEN
Microbiology 2001;28(2):68-72
Study the immunological adjuvant function of biodegradable microspheres for DNA immunization. Empty poly(D,L-lactide-co-glycolic acid) microspheres were prepared using the water-inoil-in-water(w-o-w)technique; A plasmid DNA pRc-CMV encoding hepatitis B virus S antigen was constructed;The mixture of the microspheres and the plasmid DNA was prepared by incubation method. The mixture was administered to Balb/c mice by intramuscular injection. Result: The high antibody titer (1:1600) of intramuscular injection of the mixture of microspheres and the plasmid DNA was obtained, similar to that of intramuscular injection of the mixture of AL(OH)3 and hepatitis B virus S antigen; while intramuscular injection the plasmid DNA elicited no serum antibody respones. Conclusion: biodegradable microspheres may be used as an good adjuvant for DNA immunization.
10.AN IMPROVED TECHNIQUE ON NUTIONAL GB NUTRIENT AGAR FOR COUNTING BACTERIA RIENT AGAR FOR COUNTING BACTERIA
Jiangzhen LIU ; Guozhon CHEN ; Haibo LI ; Haitao ZHOU ; Yanyan LIANG
Microbiology 2001;28(2):63-68
Both Chinese GB nutrient agar and American FDA standard method agar are commonly used for counting bacteria in food inspection. A number of our experiments showed that the count of bacteria by FDA standard method agar is 23.9% higher than that by GB nutrient agar. The present C8 medium is an improved medium based on the composition of the two media mentioned above The result of our comparison experiment showed that the C8 medium used for counting bacteria was 35.8% higher than that by GB nutrient agar and 9.5% higher than that by FDA standard method agar respectively.