Isolation and identification of bioactive substance 1-hydroxyphenazine from Pseudomonas aeruginosa and its antimicrobial activity.

A strain named as Pseudomonas aeruginosa 2016NX1, which could produce phenazine and cereusitin, was isolated from the root of Millettia specisoa. Phenazines were extracted, isolated and purified by chloroform, thin-layer chromatography, column chromatography and high-performance liquid chromatography. Then the purified materials were identified by analysis of nuclear magnetic resonance. The major yellow component is 1-hydroxyphenazine and the minor blue component is cereusitin A. The tests of antimicrobial activity of yellow component showed that the growth of several common plant pathogenic fungi and bacteria (such as Cochliobolus miyabeanus, Diaporthe citri, Salmonella sp., Klebsiella oxytoca) could be strongly inhibited. This study suggested that Pseudomonas aeruginosa strain 2016NX1 had a significant potential for biological control of phytopathogenic fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, one bioactive substance from Pseudomonas aeruginosa 2016NX1 was identified and its antimicrobial activity was verified. This study demonstrated that one bioactive substance from P. aeruginosa can strongly inhibit the growth of plant pathogenic fungi and bacteria. This study suggested that P. aeruginosa strain 2016NX1 has a significant potential for biological control of phytopathogenic fungi.

[The effect of functional endoscopic sinus surgery on mucociliary clearance].

OBJECTIVE: To explore the effect of functional endoscopic sinus surgery(FESS) on the mucociliary clearance of nasal mucosa. METHOD: 105 patients suffered from chronic sinusitis and undergone FESS from Jan. 1998 to Dec. 1998 were staged and analyzed according to the standard set up in Haikou in 1997. The nasal mucociliary transport rate (MTR) was measured by "saccharin" before, three months and six months after surgery. RESULT: 1. The difference of the stages for chronic sinusitis affected directly the surgical result. 2. The difference of properties, limits and extents of pathological changes in sinuses was significantly associated with the MTR. The MTR showed a marked reduction in stage II-II, II-III and III. The MTR was increased after surgery. 3. The difference of the stages affected directly the recovery of MTR. The MTR in stage I-I, I-II, I-III and II-I recovered more quickly. CONCLUSION: The MTR of nasal mucosa tended to recover after FESS. The study confirmed that the present staging system for chronic sinusitis was seasonable. We therefore propose the "saccharin" technique as a simple, safe, reliable and objective method of assessing the results of surgery.