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Gastric cancer is a common malignancy worldwide. The occurrence of multidrug resistance (MDR) is the major obstacle for effective gastric cancer chemotherapy. In this study, the in-depth molecular mechanism of the DJ-1-induced MDR in SGC7901 gastric cancer cells was investigated. The results showed that DJ-1 expression level was higher in MDR variant SGC7901/VCR cells than that in its parental SGC7901 cells. Moreover, DJ-1 overexpression conferred the MDR phenotype to SGC7901 cells, while DJ-1 knockdown in SGC7901/VCR cells induced re-sensitization to adriamycin, vincristine, cisplatin, and 5-fluorouracil. These results suggested that DJ-1 mediated the development of MDR in SGC7901 gastric cancer cells. Importantly, further data revealed that the activation of PI3k/Akt and Nrf2 signaling pathway were required for the DJ-1-induced MDR phenotype in SGC7901 gastric cancer cells. Meanwhile, we found that PI3k/Akt pathway was activated probably through DJ-1 directly binding to and negatively regulating PTEN, consequently resulting in Nrf2 phosphorylation and activation, and thereby inducing Nrf2-dependent P-glycoprotein (P-gp) and Bcl-2 expressions in the DJ-1-mediated MDR of SGC7901 gastric cancer cells. Overall, these results revealed that activating PTEN/PI3K/Akt/Nrf2 pathway and subsequently upregulating P-gp and Bcl-2 expression could be a critical mechanism by which DJ-1 mediates the development of MDR in SGC7901 gastric cancer cells. The new findings may be helpful for understanding the mechanisms of MDR in gastric cancer cells, prompting its further investigation as a molecular target to overcome MDR.

Traditional fermented soybean contains a variety of microflora. To obtain a comprehensive and accurate understanding of the microbial community structure and metabolic potential of fermented soybean, comparative metagenomics and metatranscriptomics were performed on a sample of fermented soybean in Yunnan Province. Metagenomic DNA and metatranscriptomic RNA were sequenced using Illumina HiseqTM2500, which yielded a total of 92,192,276 reads, with an average read length of 150 bp and 38,798,262 paired-end sequences, with an average length of 151 bp. The results show that Providencia stuartii was the most abundant species and the genes of carbohydrates (2296, 13.30%), protein metabolism (1530, 8.86%), and amino acids and amino acid derivatives (1423, 8.24%) were dominant. The expression levels of the genes belonging to amino acid transport and metabolism processes were the highest according to the reads per length of transcript in kilo-bases per million mapped reads (RPKM) values, followed by energy production and conversion and carbohydrate transport and metabolism. The metabolic pathways were primarily associated with carbohydrates, proteins and amino acids, which might be in accordance with the high levels of proteins and other nutrients in soybeans. Overall, these findings provide insights into the community structure and metabolic potential of the fermented soybean microbiome.

The goal of this study was to explore the regulatory mechanisms of phenyllactic acid (PLA) overaccumulation in Lactobacillus plantarum. The dynamics of PLA production revealed that 24 h was a suitable fermentation time, at which one of the largest differences in PLA content between strains S1 and YM-4-3 was 22.42 mg/L. Additionally, an optimization experiment showed that PLA production under the optimal condition (sample YM-4-3y) was up to 400.74 mg/L, 7.61-13.26 times as those of YM-4-3 and S1. Subsequently, an integrated analysis of genomic, transcriptomic and metabolomic data revealed that, YM-4-3 and YM-4-3y, compared with S1, although lacking a complete de novo biosynthetic pathway, increased PLA production by strengthening the core pathway and central carbon metabolism, and weakening the biosynthesis pathway of amino acids and their derivatives. These changes can provide sufficient precursors and compensate for or balance the energy consumed by the reinforced core pathway.

Lactobacillus (Lb.) plantarum is typically used as a starter culture in salt-fermented foods. Here we report 3-4% NaCl reducing the antimicrobial activity of Lb. plantarum strain YM-4-3, owing to the decrease of bacterial growth, plantaricin activity and expression levels of plantaricin biosynthesis-related genes (PBGs). Meanwhile, 1% NaCl promoted slightly the growth of YM-4-3 and up-regulated the expression of PBGs to the greatest level. The results from a spoilage experiment of fermented soybean products revealed that the 1% NaCl and YM-4-3 treatment group had the longest shelf life representing the minimum number of pathogenic bacteria and the lowest degree of mildew. Therefore, a combination of Lb. plantarum with a low concentration of salt, such as 1% NaCl, is a recommended condition for preparing fermented foods.

The objective of this study was to evaluate the effects of a three-strain yogurt formulation in slow-transit constipation (STC) patients. Each individual in both treatment groups consumed 250 mL of the formulated yogurt daily for a week (7 days), and fecal samples were collected for gut microbiota and short-chain fatty acid (SCFA) analyses. A significant increase in the defection frequency (p<0.001) and bacterial diversity (p=0.027) at the 100% sequence homology level and a decrease in the concentrations of acetic acid (p=0.014), propionic acid (p=0.019), and butanoic acid (p=0.005) were observed after the STC patients consumed three-strain yogurt formulation. In addition, the consumption of the three-strain yogurt formulation significantly altered the composition of the intestinal bacteria in the STC patients. The relative abundances of 23 genera in the top dominating genera were altered significantly after the STC patients consumed the yogurt. In summary, the consumption of 250 mL day− the three-strain yogurt formulation described in this study can play a role in improving the symptoms of STC.

Intestinal bacteria are symbiotic microbiota within the human gut and are implicated in the occurrence and development of colorectal cancer (CRC). The current study investigated the changes in bacterial composition prior to and following surgery, as well as the differences in the bacterial community structure between cancer tissue and adjacent normal tissue. The diversity of the bacterial community and the composition of the bacteria were assessed. In addition, phylogenetic analysis and principle component analysis (PCA) were performed. The results revealed that cancer tissue and adjacent normal tissue exhibited similar bacterial compositions. However, a significant difference was identified in the composition of intestinal bacteria in stool samples collected from patients following surgery compared with stool samples collected prior to surgery. Each patient had their own unique intestinal bacterial community, likely due to a number of factors, including diet, genetic factors and health status. In addition, phylogenetic trees revealed that the most abundant operational taxonomic unit, 0001, was associated with Escherichia coli in all samples. Finally, PCA suggested that the bacterial community structure in all patient stools was similar following surgery. The current study provides information regarding the diversity of the intestinal bacterial community of patients with CRC and provides a basis for postoperative intestinal assessments.

Constipation is a frequent complaint, and probiotics could have a potentially synergistic effect on intestinal transit. In the present study, yoghurt intake improved the symptoms of slow-transit constipation, which was confirmed in 144 mice (nine groups, n = 16) with loperamide-induced constipation. Yoghurt fermented with different probiotics was administered orally. Loperamide treatment caused a marked increase in first defecation time and a decrease in the charcoal transit ratio (P

The isotonic substitution of extracellular chloride by gluconate (extracellular Cl--free) has been demonstrated to elicit cardioprotection by attenuating ischaemia/reperfusion-induced elevation of intracellular chloride ion concentration ([Cl-]i). However, the downstream mechanism underlying the cardioprotective effect of extracellular Cl--free is not fully established. Here, it was investigated whether extracellular Cl--free attenuates mitochondrial dysfunction after hypoxia/reoxygenation (H/R) and whether mitochondrial permeability transition pore (mPTP) plays a key role in the extracellular Cl--free cardioprotection. H9c2 cells were incubated with or without Cl--free solution, in which Cl- was replaced with equimolar gluconate, during H/R. The involvement of mPTP was determined with atractyloside (Atr), a specific mPTP opener. The results showed that extracellular Cl--free attenuated H/R-induced the elevation of [Cl-]i, accompanied by increase of cell viability and reduction of lactate dehydrogenase release. Moreover, extracellular Cl--free inhibited mPTP opening, and improved mitochondria function, as indicated by preserved mitochondrial membrane potential and respiratory chain complex activities, decreased mitochondrial reactive oxygen species generation, and increased ATP content. Intriguingly, pharmacologically opening of the mPTP with Atr attenuated all the protective effects caused by extracellular Cl--free, including suppression of mPTP opening, maintenance of mitochondrial membrane potential, and subsequent improvement of mitochondrial function. These results indicated that extracellular Cl--free protects mitochondria from H/R injury in H9c2 cells and inhibition of mPTP opening is a crucial step in mediating the cardioprotection of extracellular Cl--free.

Folate is an important intermediate in cellular metabolism. However, because of a lack of key enzymes in the folate biosynthetic pathway, humans require supplementation with dietary folate. Some Lactobacillus plantarum strains have the ability to produce folate. To gain a better understanding of the folate biosynthetic pathway in the L. plantarum strain 4_3, which generates high folate yields, L. plantarum strain 4_3 was grown in folic acid casei medium (FACM) and fermented soybean, after obtaining a draft genome sequence. The pH values and folate yields were monitored during culturing, as were the transcriptomic profiles of cultured bacteria. The folate content increased for 12 h and then decreased before increasing again. All the genes involved in the de novo biosynthesis of folate were detected in both the genomic and transcriptomic data. The upregulation of the para-aminobenzoate biosynthesis pathway could explain the folate production in fermented soybean. Soybeans are a good substrate for the production of functional foods because of their well-suited cultivation and nutritional quality. The results of this study provide a good explanation for the high folate production observed during the fermentation of soybeans.

Lactobacillus plantarum is an important probiotic and is mostly isolated from fermented foods. We sequenced the genome of L. plantarum strain 5-2, which was derived from fermented soybean isolated from Yunnan province, China. The strain was determined to contain 3114 genes. Fourteen complete insertion sequence (IS) elements were found in 5-2 chromosome. There were 24 DNA replication proteins and 76 DNA repair proteins in the 5-2 genome. Consistent with the classification of L. plantarum as a facultative heterofermentative lactobacillus, the 5-2 genome encodes key enzymes required for the EMP (Embden-Meyerhof-Parnas) and phosphoketolase (PK) pathways. Several components of the secretion machinery are found in the 5-2 genome, which was compared with L. plantarum ST-III, JDM1 and WCFS1. Most of the specific proteins in the four genomes appeared to be related to their prophage elements.

Yond bap is a traditional fermented milk product from the Yunnan province in China. Yond baps are mostly produced with goat’s milk and occasionally with cow’s milk. As a traditional dairy product produced by fermentation, yond bap contains an abundant microflora. The microbes that play a role in the fermentation of goat milk form a specific community structure. In this work, 11 types of yond bap were characterized from four different regions in the Yunnan province. We employed bar-coded pyrosequencing of 16S rRNA to analyze the bacterial community structure in the yond baps. The results indicated that the bacterial community structures of the 11 yond baps were different. Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria were detected in all the samples. Pseudomonas, a proteobacterium, was the predominant bacterial genus. Pseudomonas sequences were detected often and in most of the samples. Next, Streptococcaceae, Lactobacillaceae, and Lactococcus belonging to Streptococcaceae family played important roles in the fermentation of yond baps as the numbers of sequences belonging to these species were higher. The results demonstrate the presence of different bacterial community structures of yond baps from different regions in the Yunnan Province of China. This study provides information about the diversity of the microbial community of fermented food and a reliable theoretical foundation for improving the quality and flavor of yond baps.

The gut microbiota is known to have a considerable impact on health; some types of organisms, including bifidobacteria and lactobacilli, are considered to be ‘good’ colonizing bacteria, while other species are potentially pathogenic. The initial colonization of a newborn infant affects his/her health in the future. Recently, research has indicated that the fetus may actually be colonized with bacteria during gestation. Accordingly, this study was conducted to assess the similarities in the bacterial species detected in the infant’s first feces with samples obtained from the mother’s placenta and vagina., BACKGROUND: The gut microbiota plays an important role in human health. It is essential to understand how the composition of the gut microbiota in neonates is established. OBJECTIVES: To investigate the nature of the microbial community in the first feces of newborn infants compared with the mothers’ placentae and vaginas. METHODS: One infant who was delivered via Cesarean section was compared with an infant who was delivered vaginally. Bar-coded pyro-sequencing of 16S ribosomal RNA genes was used to investigate the bacterial community composition and structure of each site. RESULTS: Neonatal feces of both infants had similar bacterial communities, and they were similar to the mother’s placenta regardless of the method of delivery. The vaginal bacterial community differed between the two mothers, but not different sites within the vagina. The bacteria in the neonatal feces and the mothers’ placentae demonstrated considerably higher diversity compared with the vaginas. The family Lactobacillaceae dominated in the vaginal samples, while the most abundant family in the fecal and placental samples was Micrococcineae. CONCLUSIONS: These results may provide new directions for the study of infant gut microbial formation.

Quorum sensing (QS) is a means of cell-to-cell communication that regulates, via small signalling molecules, expression of a series of genes and controls multicellular behaviour in many bacterial species. The enzyme S-ribosylhomocysteine lyase (LuxS) transforms S-ribosylhomocysteine (SRH) into 4, 5-dihydroxy-2, 3-pentanedione (DPD), the precursor of the interspecies QS signalling molecule autoinducer-2 (AI-2). In this study, two LuxS-coding genes, luxS1 and luxS2, with 70% sequence identity were isolated from Lactobacillus plantarum YM-4-3, and overexpressed in Escherichia coli BL21 (DE3), and the protein products were purified successfully. After incubation of LuxS1 or LuxS2 with SRH, the reaction products were able to induce Vibrio harveyi BB170 bioluminescence, clearly demonstrating that both LuxS1 and LuxS2 synthesize AI-2 from SRH in vitro. Ellman's assay results revealed optimal temperatures for LuxS1 and LuxS2 of 45 and 37 °C, respectively, and their activities were stimulated or inhibited by several metal ions and chemical reagents. In addition, enzyme kinetics data showed that Km, Vmax and Kcat value of LuxS1 for the substrate (SRH) were higher than that of LuxS2. These results suggest that LuxS1 and LuxS2 mediate QS in a temperature-dependent manner and may play conserved roles in AI-2 synthesis but exhibit different activities in response to external environmental stress. To our knowledge, this paper is the first report of two luxS genes present in one bacterial genome and the subsequent comparative elucidation of their functions in AI-2 production. Collectively, our study provides a solid basis for future research concerning the AI-2/LuxS QS system in L. plantarum YM-4-3.

To avoid the biases associated with PCR amplification in analysis of microbial communities, a new method has been tested for direct sequencing of the cDNA of full-length Small-subunit Ribosomal RNA withOut specific PCR amplification (SROP). In silico analysis of the SROP method demonstrated that more than 99 % of the SROP sequences could be correctly annotated. Two environmental samples (activated sludge and anaerobic sludge) with complex microbial communities were used for comparison in this study. The SROP results demonstrated that the families Rhodocyclaceae and Nitrosomonadaceae in activated sludge and the phyla Synergistetes and Spirochaetes in anaerobic sludge were underestimated by PCR-based detection. One third of the 16S ribosomal RNA (rRNA) sequences obtained by the SROP method covered the V3 amplicon region, and they are suitable for phylogenetic and diversity index analyses. The microbial diversity index calculated from the rRNA sequences by the SROP was much higher than that calculated by conventional PCR, particularly for the anaerobic sludge. The metatranscriptome-based SROP method will contribute to our better understanding of the diversity of complex microbial communities.

Fermented foods and beverages are important parts of human diet. Fen liquor, a Chinese liquor is a fermented beverage that uses a traditional fermentation process. Starters are the main microbial source and also provide nutrients for microorganisms during fermentation. In this study, starters of Fen liquor were produced through a complex traditional fermentation process. To investigate the community structure and the composition of microorganisms in the starter production process, bacterial 16S rRNA and fungal internal transcribed spacer (ITS) regions were sequenced using clone libraries and pyrosequencing, respectively. There was much higher diversity among the bacteria than among the fungi in the starter production process. Bacteria on the surface of the starters belonged mostly to the Lactobacillaceae family, while members of the Bacillacae family were dominant in the interior of the samples that lacked access to air and water. In the fungi population, diversity was high only in the raw material. In all other samples, nearly all of the fungal sequences were from Pichia kudriavzevii, a member of the Saccharomycetaceae family. Nearly all samples showed similar fungal community structures, indicating that there was little change in the fungal community. To the best of our knowledge, this is the first report to reveal the whole process of the starter production of Chinese traditional liquor. The findings obtained in this study provide new insights into understanding the composition of the microbial community during the traditional Chinese liquor starter production process and information about the production process control and monitoring.

The rmtB gene, one of the 16S rRNA methylase genes whose products confer high-level resistance to aminoglycosides, is most prevalent among Enterobacteriaceae strains. In this study, eight non-duplicate rmtB-carrying avian Escherichia coli strains from a farm in China were isolated and characterized, and further examined by phylogenetic grouping, conjugation experiments and PCR-based replicon typing. In addition, the genetic environment of rmtB was investigated by cloning and sequencing. Six rmtB-carrying E. coli were identified as phylogroup A, sequence type (ST) 156 (A-ST156), with two assigned to D-ST117; however, all of them carried the same IncI1 ST136 plasmid. The genetic environment of the rmtB gene in these eight plasmids was the same, as shown by PCR mapping. A multidrug-resistant region carrying blaTEM-1, rmtB, a class 1 integron cassette array (intI1-dfrA12-orfF-aadA2-qacEΔ1-sul1) and aacC2 was characterized on the conjugative IncI1 ST136 plasmid. Co-location of the rmtB gene with a class 1 integron cassette array and aacC2 on the conjugative plasmid will facilitate its maintenance and dissemination.

This study investigated the molecular types of the Cryptococcus neoformans species complex isolates and their clinical manifestations among human immunodeficiency virus (HIV)-positive and HIV-negative patients in southeast China in the past 15 years. The molecular types of 109 isolates from 108 patients were analyzed by the PCR fingerprinting method, sequences of internal transcribed spacers of rDNA (ITS region), and sequences of the capsule-associated gene (CAP59). In HIV-positive patients, clinical isolates were grouped into molecular types VNI (75%, 15/20), VNII (15%, 3/20), and VNIII (10%, 2/20). In HIV-negative patients, the majority of the clinical isolates were grouped into molecular types VNI (72%, 64/89), VNII (13%, 12/89), VGI (12%, 11/89), VNIII (1%, 1/89), and VGII (1%, 1/89). In reference to the mating type of the isolates, 97% (106/109) were of the MATα, 2% (2/109) were of the MATα/− and 1% (1/109) were of the MATα/a. As for the clinical manifestations of the molecular types among the patients, the average cerebrospinal fluid (CSF) pressure of the patients infected by the C. gattii was higher than that of the patients infected by the C. neoformans. These results suggest that both HIV-positive and HIV-negative cryptococcal patients in the southeast of China are mostly infected by the C. neoformans strains. No C. gattii strains were found in HIV-positive patients.

The Changjiang estuary and the coastal area of the East China Sea (ECS) represent important interfaces of terrestrial and marine environments. This study included analyses of water and sediments collected during different seasons in these regions to determine the composition of microbial assemblages by means of 16S rRNA gene clone libraries. We retrieved 1946 sequences and 779 distinct operational taxonomic units from 36 clone libraries. Shannon-Weaver diversity index values and rarefaction analysis indicated that bacterial diversity in the sediment samples was much higher than in the water samples. Proteobacteria (72.9%) was the most abundant phylum, followed by Firmicutes (6.4%), Bacteroidetes (4.6%) and Actinobacteria (4.1%). In the water, clone sequences related to Alphaproteobacteria were the most abundant, whereas in the sediment samples, sequences affiliated with Gammaproteobacteria were predominant. Principal coordinate analysis showed that water samples collected from the Changjiang estuary and the ECS clustered separately. However, this spatial pattern could not be observed in sediment samples, which were mainly distinguished from one another by the season. Bacterial diversity in the Changjiang estuary was higher than that in the ECS, which may be the result of the mixing of bacterial communities from the Changjiang River, the estuary and the coastal ocean.

PCR-based methods for rRNA gene analysis have been widely used to study diversity of microbiology. However, the analysis would be difficult when the DNA content in samples is too low to be amplified by conventional PCR. Nested PCR comes up with the advantage of higher sensitivity. It can detect target DNA at several-fold lower concentrations than conventional PCR. However, the amplification bias and factors that potentially affect measurement of sample diversity associated with nested PCR method has received little attention. Here, nested PCR was compared to reconditioning PCR which is based on conventional PCR and it would reduce the formation of heteroduplex. We investigated the use of both nested and reconditioning PCR methods to construct clone libraries of 16S rRNA genes from four swimming pool water samples. Abundances of OTUs (operational taxonomic units) were correlated between the libraries (r 2 = 0.88, P

Aims: This study aimed to determine the microbial diversity in the starter of Fen Liquor. Methods and Results: The plate method was used to enumerate the micro-organisms; meanwhile, the 16S rDNA of bacteria and the internal transcribed spacer of fungi were used to determine microbial diversity. Several genera were accordingly identified. Among the bacteria, Lactobacillales and Actinomycetales were detected only on the surface of the starter, whereas Bacillales was dominant within the starter. Among the fungi, Saccharomycopsis and Issatchenkia were the main genera in surface and interior starter, respectively; in addition, Thermomyces was found in interior starter, while other species of fungi were detected on the surface. Conclusions: The culture-dependent and polymerase chain reaction-based methods revealed the significant microbial diversity in different locations in the starter of Fen Liquor. Significance and Impact of the Study: This study is the first to identify the bacterial and fungal communities associated with the starter of Fen Liquor using both traditional and molecular methods; it is also the first to compare the microbial diversity on the surface of starter with that in the interior. The results enrich our knowledge on liquor-related micro-organisms, and can be used to promote the development of the traditional fermentation technology.

Two new phenylglycol derivatives, (S)-(+)-2-(3,4-dihydroxy phenyl)-2-ethoxyl- ethanol and (S)-(+)-2-(3,4-dihydroxy phenyl)-2-acetoxy-ethanol, were isolated from the leaves of Syringa reticulata var. mandshurica, along with two known phenethylols, p-hydroxyl phenethanol and 3,4-dihydroxy phenethanol. The planar structures of the new compounds were established on the basis of their spectral data, and their absolute stereochemistry was established by modified Mosher's method. The two known compounds were identified by comparison of spectral data with published references. The two new compounds showed conspicuous antifungal activities by agar medium assay.

An anaerobic ammonium-oxidation (anammox) reactor was operated for more than 500 days and the anammox activity of the biomass in the reactor reached 0.58 kg Ntotal/kg VSS d. The removal ratios of NO2−-N to NH4+-N in both reactor and activity tests were nearly 1.1. The bacterial diversity in the reactor was investigated by analysis of 16S rRNA gene clone libraries and quantitative real-time PCR (qPCR). The analysis showed that more than half of the clones in the library were affiliated to recognized filamentous bacteria. The previously recognized anammox bacterium (AnAOB) Candidatus Kuenenia stuttgartiensis was only detected by using a Planctomycetes-specific 16S rRNA gene primer set. However, at least two different types of AnAOB were detected by the primer set targeting the hydrazine-oxidizing enzyme gene (hzo). The aerobic ammonium-oxidizing bacteria (AAOB) Nitrosomonas europaea–eutropha group, which is widely detected in oxygen-limited environments, was also found in this reactor. The result of qPCR indicated that AnAOB comprised 16% of the community population while AAOB comprised less than 1% in the reactor.

Biological treatment of saline wastewater is considered unfavorable due to salinity inhibition on microbial activity. In this study, intertidal wetland sediment (IWS) collected from a high saline environment was investigated as a novel inoculation source for anaerobic treatment of saline pharmaceutical wastewater. Two parallel lab-scale anaerobic sequencing batch reactors (AnSBR) were set up to compare the organic removal potential of IWS with conventional anaerobic digested sludge (ADS). Under steady-state condition, IWS reactor (R(i)) showed organic reduction performance significantly superior to that of ADS reactor (R(a)), achieving COD removal efficiency of 71.4 ± 3.7 and 32.3 ± 6.1%, respectively. In addition, as revealed by fluorescent in situ hybridization (FISH) analysis, a higher relative abundance of methanogenic populations was detected in R(i). A further 16S rRNA gene pyrosequencing test was conducted to understand both the bacterial and archaeal community populations in the two AnSBRs. A predominance of halophilic/tolerant microorganisms (class Clostridia of bacteria, genera Methanosarcina, and Methanohalophilus of archaea) in R(i) enhanced its organic removal efficiency. Moreover, several microbial groups related with degradation of hardly biodegradable compounds (PAHs, n-alkenes, aliphatic hydrocarbons, and alkanes, etc.) were detected in the IWS. All these findings indicated that IWS is a promising inoculation source for anaerobic treatment of saline wastewater.

Lactobacillus plantarum is an important probiotic that is isolated mostly from fermented foods. Here, we report the first draft genome sequence of L. plantarum strain AY01, isolated from the raw material of fermented goat milk cheese. This bacterium, with optimum growth at 30°C, has a G+C content of 43.68%.

Tidal flats are soil resources of great significance. Nitrification plays a central role in the nitrogen cycle and is often a critical first step in nitrogen removal from estuarine and coastal environments. We determined the abundance as well as composition of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in different soils during land reclamation process. The abundance of AOA was higher than that of AOB in farm land and wild land while AOA was not detected in tidal flats using real-time polymerase chain reaction (PCR). The different abundances of AOB and AOA were negatively correlated with the salinity. The diversities of AOB and AOA were also investigated using clone libraries by amplification of amoA gene. Among AOB, nearly all sequences belonged to the Nitrosomonas lineage in the initial land reclamation process, i.e., tidal flats, while both Nitrosomonas and Nitrosospira lineages were detected in later and transition phases of land reclamation process, farm land and wild land. The ratio of the numbers of sequences of Nitrosomonas and Nitrosospira lineages was positively correlated with the salinity and the net nitrification rate. As for AOA, there was no obvious correlation with the changes in the physicochemical properties of the soil. This study suggests that AOB may be more import than AOA with respect to influencing the different land reclamation process stages.

This research was aimed at isolating and identifying the predominant lactic acid bacteria (LAB) in the traditional Chinese salt-fermented soybean food, douchi, from Yunnan, China. The predominant LAB present were isolated and identified by conventional culture-dependent methods combined with molecular biological methods. Two hundred and sixty isolates were obtained from thirty kinds of traditional fermented douchi from six cities and counties in Yunnan, and those strains were divided into twelve groups by their morphological and biochemical characteristics. Based on 16S ribosomal DNA (rDNA) sequencing and analysis, 56 representative strains were identified as belonging to 6 genera and 14 species: Lactobacillus (4 spp.), Weissella (3 spp.), Pediococcus (2 spp.), Staphylococcus (2 spp.), Enterococcus (1 sp.), and Bacillus (2 spp.). The results show that douchi contains a large natural population of LAB of diverse composition from which some strains could be selected as starters for functional fermented foods. This is the first study on the original douchi from Yunnan, and the results suggest that it may be a useful source for the isolation of LAB. This study has also laid a foundation for further research on developing functional douchi products.

This study endeavored to investigate the variability of bacteria and fungi present during the fermentation process of the light-fragranced distilled liquor known as Fen liquor. To accomplish this, we used a combination of clone libraries of 16S rRNA genes, bar-coded pyrosequencing of the internal transcribed spacer region 1 (ITS1), and quantitative real-time PCR (qPCR). Fifteen families of bacteria and six families of fungi were detected. More than 91% of 16S rRNA gene sequences could be assigned to the family Lactobacillaceae, which were then classified to eight different operational taxonomic units (OTUs), based on a 3% cut-off. The most abundant OTU which contributed to 51% of the total 16S rRNA gene sequences was affiliated with Lactobacillus acetotolerans and had a significantly similar variation trend with the chemical constituents detected. Sixty percent of the fungal ITS1 region sequences were affiliated with the family Saccharomycetaceae. The most abundant OTU was very similar to Issatchenkia orientalis, which displayed notable similarities with respect to the change trends in both ethanol and organic acid contents. The sequences of the second most abundant OTU were closest to Saccharomyces cerevisiae, an important species in the process of ethanol production. Furthermore, about one fourth of the ITS1 region sequences belonged to the family Saccharomycopsidaceae. Conversely, very few sequences could be grouped together with filamentous fungi. The results of qPCR showed that the content of bacteria was increased while that of fungi was more stable in the fermentation process. It is very important to simultaneously investigate bacterial and fungal variations in food-fermentation processes.

Two new phenylglycol derivatives, (S)-(+)-2-(3,4-dihydroxy phenyl)-2-ethoxyl- ethanol and (S)-(+)-2-(3,4-dihydroxy phenyl)-2-acetoxy-ethanol, were isolated from the leaves of Syringa reticulata var. mandshurica, along with two known phenethylols, p-hydroxyl phenethanol and 3,4-dihydroxy phenethanol. The planar structures of the new compounds were established on the basis of their spectral data, and their absolute stereochemistry was established by modified Mosher's method. The two known compounds were identified by comparison of spectral data with published references. The two new compounds showed conspicuous antifungal activities by agar medium assay.