PCR-DGGE Technique Research Articles

Rhizosphere-associated microbiota of Canavalia ensiformis in sulfentrazone bioremediation

The objective of this study was to determine the efficiency of the microbial rhizosphere (Canavalia ensiformis) in the phytoremediation of sulfentrazone using quantification methods (CO2 evolution, microbial biomass carbon, and metabolic quotient) and identification of bacteria (PCR-DGGE technique). The experiment was conducted in a completely randomized design, in a 2x4 factorial scheme, with four replications. The treatments were composed of rhizospheric soil (cultivated with C. ensiformis) and non-rhizosphere soil (uncultivated soil); and four levels of contamination by sulfentrazone (0, 200, 400, and 800 g ha−1 a.i.). The microbiota associated with the rhizosphere of C. ensiformis efficiently reduced sulfentrazone residues in the soil, with better performance at the dose of 200 g ha−1 a.i. Using the PCR-DGGE technique allowed the distinction of two profiles of bacteria in the rhizospheric activity of C. ensiformis. The second bacterial profile formed was more efficient in decontaminating soil contaminated with sulfentrazone residue. The microbiota associated with the rhizosphere of C. ensiformis has an efficient profile in decontaminating soils with residues equivalent to 200 g ha−1 a.i. the herbicide sulfentrazone.

Analysis of Microbial Community Structure in the Start-up Phase of SNAD Process for Domestic Sewage by PCR-DGGE Technique

Analysis of Microbial Community Structure in the Start-up Phase of SNAD Process for Domestic Sewage by PCR-DGGE Technique

Comparison of culture-dependent and culture-independent techniques in the detection of lactic acid bacteria biodiversity and dynamics throughout the ripening process: The case of Turkish artisanal Tulum cheese produced in the Anamur region.

Our objective was to analyze the diversity of the microbiota over 180 d of ripening of eight batches of artisanal goatskin Tulum cheeses by culture-dependent and culture-independent (PCR-DGGE) methods. V3 region of the bacterial 16S rRNA gene was amplified with the PCR after direct DNA isolation from the cheese samples. Nine different species and five genera were determined by culturing, while 11 species were identified in the PCR-DGGE technique. This diversity revealed the uniqueness of artisanal cheese varieties. The dominant genera in all the cheese samples were composed of Enterococcus species. The culture-dependent method revealed five genera (Enterococcus,Bacillus,Lactococcus,Lactobacillus, Sphingomonas) while three genera (Enterococcus, Streptococcus, Lactococcus) were detected in the culture-independent method. It was concluded that combining the two methods is important for characterizing the whole microbiota of the Tulum cheese varieties produced in the Anamur region.

Direct PCR-DGGE Technique Reveals Wrinkle-Lipped Free-Tailed Bat (Chaerephon plicatus Buchanan, 1800) Predominantly Consume Planthoppers and Mosquitoes in Central Thailand

Insectivorous bats may significantly contribute to human well-being by suppressing pest insects and possibly preventing the emergence of diseases. To understand the roles these bats play in their ecosystems, a diet analysis of their guano can be carried out. However, each diet analysis method has its drawbacks, e.g., some soft-bodied insects might be missed in microscopic analysis of guano. We aimed to examine the diet of the wrinkle-lipped free-tailed bats (Chaerephon plicatus) using direct PCR and DGGE (denaturing gradient gel electrophoresis) technique. Sequencing was done for 240 guano samples collected from two caves in Thailand over the course of a year. Direct PCR and DGGE was successfully applied for bat guano analysis. Seventy-six Operational Taxonomic Units were identified, in which 25 were determined to the species level. Diptera was the most abundant insect order found in bats' diet, with a percentage frequency of occurrence (%FOO) of 32.8%, followed by Hemiptera (27.2%), Lepidoptera (24.1%) and Coleoptera (10.3%). Hemipterans were preferred during active rice-growing months, while dipterans were consumed year-round. Eight known crop pests were found, and the brown planthopper (Nilaparvata lugens) was the most dominant throughout the year. Mosquitoes also substantially contributed to the bat's diet. The bats probably encounter these insects during insect dispersal at high elevations. The prey species recorded strongly indicated that this bat plays a role in facilitating rice and crop productions, which increases food security. In addition, this bat may play a role in suppressing potential disease-carrying insects such as various species of mosquitoes. We urge local and international authorities to increase conservation efforts and that similar studies should be done with other bat species.

Assessment of the migration of the operational taxonomic units (OTUs) from rice rhizosphere to endosphere

An experiment was conducted to understand the migration of the OTUs from rice rhizosphere to endosphere at vegetative and flowering stages of the crop. The soil and plant samples were studied through culture independent molecular PCR-DGGE technique involving denaturing gradient gel electrophoresis (DGGE) of PCR-amplified V3 region of 16S rRNA gene. The DGGE analysis revealed higher species richness in soil, followed by root, stem and leaf. The analyses for range-weighted richness and Shannon diversity index indicated vegetative stage carries more diverse microflora in soil and root samples than stem and leaf samples. The Sorenson’s similarity index indicates the migration of bacterial population from rhizosphere to endosphere. The soil samples shared about 28 to 35 % similarity with different plant compartments viz., root, stem and leaf at both crop stages. The fingerprinting of rhizosphere and endosphere samples would be a useful resource for plant microbe breeding through understanding of the associated microbial community.st

Nghiên cứu đa dạng vi khuẩn trong trầm tích biển tại quần đảo Trường Sa bằng phương pháp truyền thống kết hợp kỹ thuật điện di biến tính

The denaturing gradient gel electrophoresis (DGGE) is an effective culture-independent technique for assessing diversity of microbial communities. In this study, the PCR-DGGE technique was applied for analyzing the diversity of bacterial communities in marine sediment in the Truong Sa archipelago (Spratly Islands), Vietnam, and a comparison with cultivable bacterial fraction was performed. Three sediment samples taken from different depths were used in the study. A total of 17 bacterial strains were isolated and divided into 6 groups based on their colony and cell morphologies. Comparative analyses of nearly full-length 16S rDNA sequences retrieved from six representative strains of these morphologically distinguished groups indicated that they were most closely related to Bacillus amyloliquefaciens, Bacillus filamentosus, Bacillus endophyticus, Bacillus licheniformis, Pseudomonas balearica, and Raoultella ornithinolytica. The PCR-DGGE analyses carried out with the three sediment samples showed relatively diverse bacterial communities with 9 distinct bands, 6 of which were related to the isolated representatives, whereas the other three were identified as Vibrio proteolyticus, Priestia filamentosa, and Clostridium halophilum. Thus, by applying the PCR-DGGE technique, more thorough information on bacterial communities in the sediment of Truong Sa archipelago could be elucidated, providing useful information for further studies on the conservation and utilization of microbial resources in this ecosystem.

Improved PCR-DGGE analysis by emulsion-PCR for the determination of food geographical origin: A case study on Greek PDO “avgotaracho Mesolonghiou”

Greek avgotaracho Mesolonghiou (fish eggs from Flathead Mullet) is a highly valuable food product which holds Protected Destination of Origin status. The aim of this work was to use PCR-DGGE technique to examine whether there is a correlation between bacteria population in fish eggs and geographical origin. Cluster analysis of fish eggs from three geographical locations (Mesolonghi, Australia and Mauritania) discriminated samples according to their provenance. Moreover, we utilized emulsion-PCR amplification in DGGE analysis in order to investigate whether we could obtain further information about food products’ bacteria communities. PCR-DGGE proved to be a suitable method for fish eggs traceability, moreover emulsion PCR-DGGE provides better results. Emulsion-PCR can face up the existing limitations of conventional PCR and thus can be demonstrated as alternative molecular technique for complex and processed matrices, regarding food traceability and authentication.

Effective microorganisms: Microbial diversity and its effect on the growth of palisade grass

Effective microorganisms (EM) are inoculants used by farmers on various crops, and the actual efficiency of EM and their composition have been widely discussed. The objective of this study was to analyze the profile of the microbial community in soils after applying 3 EM inoculants from different origins with and without manure and to determine the impacts on growth and chemical composition of Urochloa brizantha (palisade grass). We showed, by PCR-DGGE technique, that the community structure of the fungi and bacteria in soil differed with EMs from different sources and that adding manure to the soil also significantly altered the bacterial and fungal profile. We also found that adding manure to soil resulted in a pronounced increase in both dry matter yield and crude protein concentration in palisade grass, while benefits of applying EM were largely restricted to a farmer-produced inoculant, where CP% was increased and NDF% was reduced when applied along with manure.

Longitudinal characterization of bifidobacterial abundance and diversity profile developed in Thai healthy infants

The early bifidobacterial colonization and development of infant gut is considered crucial for the immediate and lifelong health of human host. This study longitudinally analyzed and characterized fecal bifidobacterial profiles in association with feeding regimens observed in six infants during 5months after birth. The dominant fecal microbiota of bifidobacteria, lactobacilli/enterococci, clostridia, bacteroides and eubacteria were specifically enumerated using fluorescent in situ hybridization (FISH) technique. Breastfeeding exhibited close association with the predomination of bifidobacteria with the highest relative abundance of 32-70% detected in both infants with exclusive breastfeeding. The nested PCR-DGGE technique revealed high diversity existing within a bifidobacterial species with multiple strain variantsof B. bifidum, B. longum, B. breve and B. dentium continuously detected in feces of exclusively breast- and combination-fed infants over the period of 5months. Contrarily, B. breve, B. adolescentis, B. dentium, B. bifidum, B. faecale, B. kashiwanohense and B. lactis detected in all exclusively formula-fed infants seem to be transient species. The persisting strains seem to derive primarily from maternal breastmilk as demonstrated by PCR-DGGE profiles of human milk and feces from three mother-infant pairs. The results suggested the pivotal role of breastfeeding regimen in supporting colonization and succession of bifidobacteria in infant gut.

Influence of different sources of contamination on the microbiological quality of lettuce in the Teresópolis region, RJ, Brazil

ABSTRACT Irrigation water and cultivated soil have been identified as possible sources of contamination in several crops. In certain vegetables that are eaten raw, such as lettuce, this contamination can lead to public health problems. Aiming to evaluate the influence of these sources on the quality of lettuce grown in the Córrego Sujo Basin, Teresópolis, RJ, an important agricultural pole whose production services the metropolitan region of Rio de Janeiro, water from different sources (spring, weir and river) was collected in this region, as well as samples of soil and lettuce irrigated with these waters, to carry out conventional microbiological analyzes (counts of total heterotrophic bacteria and thermotolerant coliforms) and molecular analyzes (PCR-DGGE). The count of fecal coliforms in lettuce suggests that there is an influence of irrigation water and the cultivated soil on the contamination of these vegetables. The grouping of bacterial communities in the different samples obtained by the PCR-DGGE technique shows that irrigation water has a greater influence on the contamination of these vegetables in relation to the soil where they are grown. These results corroborate the need to monitor water bodies used for irrigation and demonstrate that the PCR-DGGE technique is of great value for the study of microbial communities and, when associated with specific primers, can help in the detection of pathogens in food.

不同土壤深度对宁夏石嘴山盐碱地细菌菌群多样性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 不同土壤深度对宁夏石嘴山盐碱地细菌菌群多样性的影响 DOI: 10.5846/stxb201805141055 作者: 作者单位: 中国水产科学研究院淡水渔业研究中心,中国水产科学研究院淡水渔业研究中心,中国水产科学研究院淡水渔业研究中心 作者简介: 通讯作者: 中图分类号: 基金项目: 中国水产科学研究院基本科研业务费（2016ZD0604）；中国水产科学研究院淡水渔业研究中心基本科研业务费（2017JBFM13） Effect of depth on bacterial diversity in saline-alkali soil in Shizuishan region in Ningxia Author: Affiliation: Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences,Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences,Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences Fund Project: Special Scientific Research Funds for Central Non-profit Institutes, Chinese Academy of Fishery Sciences（NO.2016ZD0604）；Central Public-interest Scientific Institution Basal Research Fund, Freshwater Fisheries Research Center, CAFS (NO. 2017JBFM13) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:宁夏自治区是我国受到土壤次生盐渍化危害的重点区域，然而对该地区盐碱化形成机制及影响因素的研究资料较少。在宁夏石嘴山地区采集土壤样本，采用基于16S rRNA的PCR-DGGE技术对不同深度土壤的细菌群落多样性和优势种群进行分析，以期从土壤生态角度探索该地盐渍化成因及改良措施。带谱相似性和UPGMA聚类结果表明，表层（D < 20 cm）土壤和底层（D > 80 cm）土壤样本中细菌菌群相似程度较高；而中间层（20 cm < D < 80 cm）土壤样本中细菌菌群相似程度很低。多样性指数分析显示，随着地层深度的增加，菌落的丰富度和多样性均趋于下降；而均匀程度变化幅度不大。对其中5个优势条带进行测序比对的结果表明，该地区土壤可识别优势细菌菌群为变形细菌门Proteobacteria和拟杆菌门Bacteroidetes，但大部分条带未可识别。结果表明该地区盐碱土壤中的细菌菌群多样性程度较高，且优势菌群不尽相同；土壤深度与细菌菌落多样性在一定程度上存在线性关系。为深入研究次生盐渍化土壤的形成机制以及影响因素提供理论参考。 Abstract:As a key area affected by secondary soil salinization in China, there is limited relevant research data on the formation mechanisms, as well as their influencing factors, in the Ningxia Autonomous Region. In this study, soil samples were collected at various soil depths in the Shizuishan area, Ningxia. A 16S rRNA-related PCR-DGGE technique was used to analyze bacterial diversity and dominant populations at different depths to explore the causes of salinization and its improvement measures from the perspective of soil ecology. Results from band similarity and UPGMA clustering indicated that the degree of bacterial diversity in the surface (D < 20 cm) and bottom (D > 80 cm) layers were similar and relatively high, whereas it was low in the middle layer (20 cm < D < 80 cm). The diversity indices analysis demonstrated that with increasing depth, the degree of richness and diversity tended to decline; whereas the degree of uniformity did not change considerably. Sequence comparison of five clones showed that the most predominant bacterial communities in this region were Proteobacteria and Bacteroidetes, whereas the remaining bands were not identified. The results of this study indicated that the degree of microbial diversity in saline-alkali soil in this area is very high, and the predominant bacterial flora is not the same. Generally, the bacterial diversity showed a linear relationship with depth, which is possibly related to the soil moisture content. However, more profound and in-depth data is needed to support this study. This study aimed to provide a theoretical reference for further in-depth study on secondary salinized soil formation mechanisms and their influencing factors. 参考文献 相似文献 引证文献

COMPARISON EFFICACY OF ITS AND 18S rDNA PRIMERS FOR DETECTION OF FUNGAL DIVERSITY IN COMPOST MATERIAL BY PCR-DGGE TECHNIQUE

Through composting process, biosolid wastes are gradually transformed into compost material which can be used as soil fertilizer. Among microorganisms involved in composting process, fungi play important roles because they break down complex substrates, such as ligno-cellulose. Recently, PCR-DGGE technique has been considered as a useful tool for analysis of fungal diversity in environmental samples. Among other factors, primer set selection is necessary for successful of the PCR-DGGE analysis. There are several PCR primer sets targeting fungal variable regions of 18S ribosomal DNA (rDNA) and internal transcribed spacer (ITS) for the use in community analyses, however there exist just few reports on efficacy of these primers in studying fungal communities in compost materials. In this study, four different primer sets were tested, including EF4/Fung5 (followed by EF4/NS2-GC), EF4/ITS4 (followed by ITS1F-GC/ITS2), NS1/GC-Fung, and FF390/FR1-GC. Extracted DNA from compost materials often contains co-extracted humic substances and other PCR inhibitors. Therefore, the primers were tested for (i) tolerance to the PCR inhibitors presenting in the DNA extracted from compost materials, and (ii) efficacy and specificity of the PCR. The results showed that of the four primer sets, only FF390/FR1-GC achieved both criteria tested whereas the other three did not, i.e. primer EF4/ITS4 had low tolerance to PCR inhibitors, primers EF4/Fung5 was low in PCR amplification efficacy, whereas primers EF4/ITS4 created unspecific products. DGGE analyses of PCR products amplified with the primer set FF390/FR1-GC showed single bands for reference pure cultures Penicillium sp., Aspergillus sp., and Trichoderma sp., as well as distinctly separated bands for the fungal communities of three different composting materials. Thus, the primer set FF390/FR1-GC could be suitable for studying structure and dynamic of fungal communities in compost materials.

Biohydrogen production from palm oil mill effluent (POME) by two stage anaerobic sequencing batch reactor (ASBR) system for better utilization of carbon sources in POME

The production of biohydrogen through dark fermentation of palm oil mill effluent (POME) was evaluated in two-stages of biohydrogen in an anaerobic sequencing batch reactor (ASBR) system using enriched mixed culture for the first time. This study attempts to examine the effect of HRT and its interaction behavior with the solid retention time (SRT), and the sugar consumption. The effluent after discharged from the thermophilic reactor contained 7.61 g/L TC and 22.87 g/L TSS was fed to the secondary mesophilic reactor system. Results indicated that the overall sugar consumption reached 88.62% at the optimum HRT of 12 h with the SRT set to 20 h. The optimum hydrogen yield and HPR in the thermophilic stage were 2.99 mol H2/mol-sugar and 8.54 mmol H2/L·h respectively, while for the mesophilic stage were 1.19 mol H2/mol-sugar and 1.47 mmolH2/L·h respectively. The overall HPR showed an improvement and increase from 8.54 mmol H2/L·h to 10.34 mmol H2/L.h. Microbial community analysis of mixed culture in the two-stage thermophilic (55.0 °C) and mesophilic (37.0 °C) ASBR reactor was dominated by Thermoanaerobacterium sp. based on the PCR-DGGE technique.

Evaluation of different air dosing strategies to enhance H2S removal in microaerobic systems treating low-strength wastewaters

ABSTRACT This study aimed to evaluate different air dosing strategies such as microaeration flow rates and air dosing points to enhance H2S removal in microaerobic systems treating low-strength wastewaters. Efficiency and stability of the reactors, as well as biogas quality, were assessed, and microbial community changes were evaluated using the PCR-DGGE technique. The results showed that the air dosing point affected the H2S concentration and that air dosing at the headspace promoted the highest H2S removal efficiency. The airflow rate also affected the process, since H2S concentration in the biogas was higher at 0.1 mL air.min−1 than at 0.3 mL air.min−1. The methane concentration in the biogas was also affected by both air dosing point and flow rate, since the lowest value was observed at the highest airflow rate of the headspace dosing point, due to dilution by the N2 influx applied to the system. The highest productivity and operational efficiency were observed at this air dosing point, with this airflow (HD0.3), which corroborates with the operational results and the ecological parameters, since the microaeration at this stage promoted high bacterial and archaeal species richness and diversity, optimum functional organization, high COD and H2S removal efficiencies.

Ecology and biotechnological potential of bacterial community from three marine sponges of the coast of Rio de Janeiro, Brazil.

Marine sponges has been a large reservoir of microbial diversity, with the presence of many species specific populations as well as producing biologically active compounds, which has attracted great biotechnological interest. In order to verify the influence of the environment in the composition of the bacterial community present in marine sponges and biotechnological potential of bacteria isolated from these organisms, three species of sponges and the waters surrounding them were collected in different beaches of Rio de Janeiro, Brazil. The profile of the bacterial community present in sponges and water was obtained by PCR-DGGE technique and the biotechnological potential of the strains isolated by producing amylase, cellulase, protease and biosurfactants. The results showed that despite the influence of the environment in the composition of the microbial community, studied marine sponges shown to have specific bacterial populations, with some, showing potential in the production of substances of biotechnological applications.

Application of Reverse Transcriptase-PCR-DGGE as a rapid method for routine determination of Vibrio spp. in foods

The aim of this research was to evaluate the feasibility of PCR-DGGE and Reverse Transcriptase-PCR-DGGE techniques for rapid detection of Vibrio species in foods. Primers GC567F and 680R were initially evaluated for amplifying DNA and cDNA of ten references Vibrio species by PCR method. The GC-clamp PCR amplicons were separated according to their sequences by the DGGE using 10% (w/v) polyacrylamide gel containing 45–70% urea and formamide denaturants. Two pair of Vibrio species, which could not be differentiated on the gel, was Vibrio fluvialis - Vibrio furnissii and Vibrio parahaemolyticus - Vibrio harveyi. To determine the detection limit, in the community of 10 reference strains containing the same viable population, distinct DNA bands of 3 species; Vibrio cholerae, Vibrio mimicus and Vibrio alginolyticus were consistently observed by PCR-DGGE technique. In fact, 5 species; Vibrio cholerae, Vibrio mimicus, Vibrio alginolyticus, Vibrio parahaemolyticus and Vibrio fluvialis consistently observed by Reverse Transcriptase-PCR-DGGE. In the community containing different viable population increasing from 102 to 105CFU/mL, PCR-DGGE analysis only detected the two most prevalent species, while RT-PCR-DGGE detected the five most prevalent species. Therefore, Reverse Transcriptase-PCR-DGGE was also selected for detection of various Vibrio cell conditions, including viable cell (VC), injured cells from frozen cultures (IVC) and injured cells from frozen cultures with pre-enrichment (PIVC). It was found that cDNA band of all cell conditions gave the same migratory patterns, except that multiple cDNA bands of Plesiomonas shigelloides under IVC and PIVC conditions were found. When Reverse Transcriptase-PCR-DGGE was used for detecting Vibrio parahaemolyticus in the pathogen-spiked food samples, Vibrio parahaemolyticus could be detected in the spiked samples containing at least 102CFU/g of this pathogen. The results obtained also corresponded to standard method (USFDA, 2004). In comparison with the detection of the Vibrio profiles in fourteen food samples using standard method, Reverse Transcriptase-PCR-DGGE resulted in 100%, 75% and 50% similarity in 3, 1 and 6 food samples, respectively.

Classification of Culturable Bifidobacterial Population from Colonic Samples of Wild Pigs (Sus scrofa) Based on Three Molecular Genetic Methods.

Occurrence of bifidobacteria, known as health-promoting probiotic microorganisms, in the digestive tract of wild pigs (Sus scrofa) has not been examined yet. One hundred forty-nine fructose-6-phosphate phosphoketolase positive bacterial strains were isolated from colonic content of twenty-two individuals of wild pigs originated from four localities in the Czechia. Based on PCR-DGGE technique targeting the variable V3 region of the 16S rRNA genes, strains were initially differentiated into four groups represented by: (i) probably a new Bifidobacterium species (89 strains), (ii) B. boum/B. thermophilum/B. thermacidophilum subsp. porcinum/B. thermacidophilum subsp. thermacidophilum (sub)species (49 strains), (iii) Pseudoscardovia suis (7 strains), and (iv) B. pseudolongum subsp. globosum/B. pseudolongum subsp. pseudolongum (4 strains), respectively. Given the fact that DGGE technique did not allow to differentiate the representatives of thermophilic bifidobacteria and B. pseudolongum subspecies, strains were further classified by the 16S rRNA and thrS gene sequences. Primers targeting the variable regions of the latter gene were designed to be applicable in identification and phylogeny of Bifidobacteriaceae family. The 16S rRNA-derived phylogenetic study classified members of the first group into five subgroups in a separated cluster of thermophilic bifidobacteria. Comparable results were obtained by the thrS-derived phylogenetic analysis. Remarkably, variability among thrS sequences was higher compared with 16S rRNA gene sequences. Overall, molecular genetic techniques application allowed to identify a new Bifidobacterium phylotype which is predominant in the digestive tract of examined wild pigs.

Microbial Diversity during Fermentation of Sweet Paste, a Chinese Traditional Seasoning, Using PCR-Denaturing Gradient Gel Electrophoresis.

The aim of this study was to elucidate the changes in the microbial community and biochemical properties of a traditional sweet paste during fermentation. PCR-denaturing gradient gel electrophoresis (DGGE) analysis showed that Aspergillus oryzae was the predominant species in the koji (the fungal mixture), and the majority of the fungi isolated belonged to two Zygosaccharomyces species in the mash. The bacterial DGGE profiles revealed the presence of Bacillus subtilis during fermentation, and Lactobacillus acidipiscis, Lactobacillus pubuzihii, Lactobacillus sp., Staphylococcus kloosi, and several uncultured bacteria were also detected in the mash after 14 days of main fermentation. Additionally, during main fermentation, amino-type nitrogen and total acid increased gradually to a maximum of 6.77 ± 0.25 g/kg and 19.10 ± 0.58 g/kg (30 days) respectively, and the concentration of reducing sugar increased to 337.41 ± 3.99 g/kg (7 days). The 180-day fermented sweet paste contained 261.46 ± 19.49 g/kg reducing sugar and its pH value remained at around 4.65. This study has used the PCR-DGGE technique to demonstrate the microbial community (including bacteria and fungi) in sweet paste and provides useful information (biochemical properties) about the assessment of the quality of sweet paste throughout fermentation.

Monitoring of changes in lactic acid bacteria during production of Thai traditional fermented shrimp (Kung-Som) by culturing method and PCR-DGGE technique

Monitoring of changes in lactic acid bacteria during production of Thai traditional fermented shrimp (Kung-Som) by culturing method and PCR-DGGE technique

Assessment of commercial probiotic products in China for labelling accuracy and probiotic characterisation of selected isolates

Microbial populations in probiotic supplements in China were investigated using the plate count method and PCR–DGGE technique. Our results indicated that total viable cells in most probiotic products could meet the minimum requirement of the Chinese National Standards (106 CFU/mL); however, total viable cell counts of the species detected in the probiotic products did not correspond with the cell number given in the label.