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Lycopodium japonicum Thunb. has attracted great interests due to its rich alkaloids with significant anticancer activity. However, significant chemical differences often exist in a plant species from different geographic origins and affect its quality and bioactivities. Thus, it is urgent to reveal their chemical and biological distinctions at the molecular level. In this context, a comparative chemical analysis of LAs using HPLC-UV-ESI-MS/MS was firstly conducted and resulted in the detection of 46 LAs, 28 of which were identified, and a series of unique LAs markers, such as peaks 2, 9, 10, and 11, were further found to be characteristic LAs and selected as markers from four different origins for their quality control. In parallel, the comparative bioactivity assay revealed that the total LAs from Hubei province exhibited much higher inhibitory rate at 65.95% against HepG2 cells than those at 26.72%, 20.26%, and 33.62% for Kenya, Guangxi province, and Zhejiang province in China, respectively. To this end, significant chemical fingerprinting differences and discrepancies in bioactivity of LAs were explored firstly, which could provide valuable information for quality control and further activity studies on LAs from different sources and promote their better pharmaceutical applications in the future as well. [ABSTRACT FROM AUTHOR]

An investigation was conducted on the phytoplankton's community composition, abundance, and their relations with environmental factors in Beixi of Jiulongjiang River, Fujian Province in February (dry season), May (wet season), and October (normal season), 2011. A total of 107 phytoplankton species were identified, belonging to 64 genera and 7 phyla. The dominant species changed with seasons. Campylomonas marssoni and Cyclotella meneghiniana dominated in dry season, Scenedesmus quadricauda and Crucigenia tetrapedia dominated in wet season, and Merismopedia tenuissima dominated in normal season. The phytoplankton's abundance was the highest in dry season (averaged 154. 77×104 cells ⋅L-1), followed by in normal season (76. 40×104 cells ⋅L-1), and in wet season (45.40×104 cells ⋅L-1). The abundance in dry and normal seasons was significantly positively correlated with water ammonium nitrogen concentration (P<0. 05), while that in wet season was significantly positively correlated with water temperature (P<0. 01). Canonical correspondence analysis (CCA) showed that water temperature was the most important factor affecting the phytoplankton's community structure, and dissolved phosphorous concentration also played important role for the community structure. The CCA ordination plots could well display the phytoplankton's community structure and its relationships with environmental factors. [ABSTRACT FROM AUTHOR]

A 3-year pot experiment with 8-year continuously cropped greenhouse cucumber soil was conducted to study the effects of different cultivation systems on the soil quality, soil nematode quantity, and crop yields. The third year's data were taken into analysis. Comparing with traditional cultivation system (two seasons planting cucumber with fallowing in summer), planting leafy vegetable and garlic in summer increased the yields of the two crops and the soil microbial biomass carbon content, total microbial population, and sucrase activity, decreased the amounts of soil nematode and root-knot nematode, and maintained a relative high Shannon-Weaver index. Planting crown daisy, garlic, and spinach in summer increased soil sucrase activity by 8.9%,89.5%, and 36.9%, and the planting of crown daisy and garlic also increased the Shannon-Weaver index by 7.7% and 9.4%, respectively. All the results suggested that catching crop and rotation had definite restoration effects on the soil quality under continuously cropping of cucumber, and the effects of planting crown daisy and garlic were more significant. [ABSTRACT FROM AUTHOR]

An investigation was conducted on the phytoplankton' s community composition, abundance, and their relations with environmental factors in Beixi of Jiulongjiang River, Fujian Province in February (dry season), May (wet season), and October (normal season), 2011. A total of 107 phytoplankton species were identified, belonging to 64 genera and 7 phyla. The dominant species changed with seasons. Campylomonas marssoni and Cyclotella meneghiniana dominated in dry season, Scenedesmus quadricauda and Crucigenia tetrapedia dominated in wet season, and Merismopedia tenuissima dominated in normal season. The phytoplankton's abundance was the highest in dry season (averaged 154.77 x 10(4) cells x L(-1)), followed by in normal season (76.40 x 10(4) cells x L(-1)), and in wet season (45.40 x 10(4) cells x L(-1)). The abundance in dry and normal seasons was significantly positively correlated with water ammonium nitrogen concentration (P<0.05) , while that in wet season was significantly positively correlated with water temperature (P<0.01). Canonical correspondence analysis (CCA) showed that water temperature was the most important factor affecting the phytoplankton's community structure, and dissolved phosphorous concentration also played important role for the community structure. The CCA ordination plots could well display the phytoplankton' s community structure and its relationships with environmental factors.

A 3-year pot experiment with 8-year continuously cropped greenhouse cucumber soil was conducted to study the effects of different cultivation systems on the soil quality, soil nematode quantity, and crop yields. The third year' s data were taken into analysis. Comparing with traditional cultivation system (two seasons planting cucumber with fallowing in summer) , planting leafy vegetable and garlic in summer increased the yields of the two crops and the soil microbial biomass carbon content, total microbial population, and sucrase activity, decreased the amounts of soil nematode and root-knot nematode, and maintained a relative high Shannon-Weaver index. Planting crown daisy, garlic, and spinach in summer increased soil sucrase activity by 8.9%, 89.5%, and 36.9%, and the planting of crown daisy and garlic also increased the Shannon-Weaver index by 7.7% and 9.4%, respectively. All the results suggested that catching crop and rotation had definite restoration effects on the soil quality under continuously cropping of cucumber, and the effects of planting crown daisy and garlic were more significant.

The title compound, [Ag(C(7)H(4)ClO(2))(C(6)H(8)N(2))(2)], is a mononuclear silver(I) complex. The Ag(I) atom is three-coordinated by two pyridine N atoms from two 5-methyl-pyridin-2-ylamine ligands and by one O atom of a 4-chloro-benzoate ligand, forming a distorted T-shaped coordination. In the crystal structure, the mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains running along the b axis.

Nocardia, Rhodococcus and Streptomyces, all members of the actinomycetes family, are Gram-positive eubacteria with high G+C content and able to form mycelium. We report here a newly identified plasmid pXT107 of Nocardia sp. 107, one of the smallest circular plasmids found in Nocardia. The complete nucleotide sequence of pXT107 consisted of 4335 bp with 65% G+C content, and encoded one replication extragenic palindromic (Rep) and six hypothetical proteins. The Rep, double-strand origin and single-strand origin of pXT107 resembled those of typical rolling-circle-replication plasmids, such as pNI100 of Nocardia, pRE8424 of Rhodococcus and pIJ101 of Streptomyces. The Escherichia coli-Nocardia shuttle plasmid pHAQ22, containing the rep gene of pXT107, is able to propagate in Nocardia but not in Streptomyces.

A gene replacement/disruption system of Amycolatopsis mediterranei U32 was developed based on the established electroporation conditions as well as appropriate selective markers. Through two-step selection, ahbas gene in U32 was replaced by a promoterless alpha-amylase gene constructed on the plasmid pDK110 of E. coli. The first single-crossover and the second double-crossover frequencies were approximately 0.5%-0.7% and 2%, respectively. Denaturation of the plasmid pDK110 increased the integration frequency about 7-10 folds, while electric shock treatment of the single-crossover recombinants increased the frequency of second crossover recombination about 5 folds. Employing denatured DNA fragments containing an apramycin-resistance gene flanked with regions of the respective genes, One-step disruption of rifO and amrA genes of U32 was also achieved with an efficiency of 30-50 transformants per microgram of DNA.