Effect of compost temperature on oxygen uptake rate, specific growth rate and enzymatic activity of microorganisms in dairy cattle manure

Investigations were carried out to find out the relationship between temperature and microbial activity in dairy cattle manure composting using oxygen uptake rate, specific growth rate and enzymatic activities during autothermal and isothermal composting experiments. In autothermal composting, oxygen uptake rate and specific growth rate were found to be most intensive in order of 43 degrees C, 60 degrees C and 54 degrees C. Isothermal composting at 54 degrees C resulted highest levels of enzymatic activity and promoted the volatile solids reduction. Based on the maximum enzymatic activity, specific growth rate appeared to be more closely linked with microbial activity in compost than with oxygen uptake rate. The enhancement of specific growth rate, enzymatic activity and volatile solids reduction were induced at 54 degrees C in cattle manure composting.     

Growth of ammonia-oxidizing archaea and bacteria in cattle manure compost under various temperatures and ammonia concentrations

A recent study showed that ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) coexist in the process of cattle manure composting. To investigate their physiological characteristics, liquid cultures seeded with fermenting cattle manure compost were incubated at various temperatures (37°C, 46°C, or 60°C) and ammonium concentrations (0.5, 1, 4, or 10?mM NH (4) (+) -N). The growth rates of the AOB and AOA were monitored using real-time polymerase chain reaction analysis targeting the bacterial and archaeal ammonia monooxygenase subunit A genes. AOB grew at 37°C and 4 or 10?mM NH (4) (+) -N, whereas AOA grew at 46°C and 10?mM NH (4) (+) -N. Incubation with allylthiourea indicated that the AOB and AOA grew by oxidizing ammonia. Denaturing gradient gel electrophoresis and subsequent sequencing analyses revealed that a bacterium related to Nitrosomonas halophila and an archaeon related to Candidatus Nitrososphaera gargensis were the predominant AOB and AOA, respectively, in the seed compost and in cultures after incubation. This is the first report to demonstrate that the predominant AOA in cattle manure compost can grow and can probably oxidize ammonia under moderately thermophilic conditions.     

Effect of matured compost as a bulking and inoculating agent on the microbial community and maturity of cattle manure compost

Cattle manure composts were consecutively manufactured. Compost that reached maturity first was used as a bulking and inoculating agent for subsequent compost production. The microbial community was measured through phospholipid fatty acid analysis. Changes in the content of fatty acid methyl esters derived from phospholipids were similar in all the composts. The diversity index for the fatty acid methyl ester content increased in the secondary-produced compost from the onset of composting. Microbial succession was accelerated using matured compost. The proportion of biomarker fatty acids for gram-positive bacteria also increased in the secondary-produced compost from the early stage of composting. Changes in germination index indicated the maturity stage of the compost. The proportion of biomarker fatty acids for gram-positive bacteria was positively correlated to the germination index, indicating that phospholipid fatty acid analysis is an indicator for evaluating the maturity of cattle manure composts.     

Effect of temperature and temperature fluctuation on thermophilic anaerobic digestion of cattle manure

The influence of temperature, 50 and 60 degrees C, at hydraulic retention times (HRTs) of 20 and 10 days, on the performance of anaerobic digestion of cow manure has been investigated in completely stirred tank reactors (CSTRs). Furthermore, the effect of both daily downward and daily upward temperature fluctuations has been studied. In the daily downward temperature fluctuation regime the temperatures of each reactor was reduced by 10 degrees C for 10 h while in the daily upward fluctuation regime the temperature of each reactor was increased 10 degrees C for 5 h. The results show that the methane production rate at 60 degrees C is lower than that at 50 degrees C at all experimental conditions of imposed HRT except when downward temperature fluctuations were applied at an HRT of 10 days. It also was found that the free ammonia concentration not only affects the acetate-utilising bacteria but also the hydrolysis and acidification process. The upward temperature fluctuation affects the maximum specific methanogenesis activity more severely as compared to imposed downward temperature fluctuations. The results clearly reveal the possibility of using available solar energy at daytime to heat up the reactor(s) without the need of heat storage during nights, especially at an operational temperature of 50 degrees C and at a 20 days HRT, and without the jeopardising of the overheating.     

Characterization of dairy cattle manure/wallboard paper compost mixture

The aim of this research was to evaluate the use of manufacturing wallboard paper scraps as an alternative bulking agent for dairy cattle manure composting. The characteristics of the composting process were studied based on the changes in physico-chemical parameters and final compost quality. Composting of dairy cattle manure with wallboard paper was performed in a 481-L cylindrical reactor with vacuum-type aeration. Rapid degradation of organic matter was observed during the thermophilic stage of composting due to high microbial activity. High temperature and alkaline pH conditions promoted intense ammonia emission during the early stage of composting. The number of mesophilic and thermophilic microorganisms were found to be affected by changes in temperature at different composting stages. The total nitrogen (N), phosphorus (P), potassium (K), and sodium (Na) concentrations of the mixture did not change significantly after 28days of composting. However, the presence of gypsum in the paper scraps increased the calcium content of the final compost. The wallboard paper had no phyto-inhibitory effects as shown by high germination index of final compost (GI=99%).     

Effect of anaerobic digestion temperature on odour, coliforms and chlortetracycline in swine manure or monensin in cattle manure

Aims: This study evaluated the effect of anaerobic digestion at 22, 38 and 55°C on odour, coliforms and chlortetracycline (CTC) in swine manure or monensin (MON) in cattle manure. Methods and Results: Swine or cattle were fed the respective growth promotant, manure was collected, and 2‐l laboratory methane digesters were established at the various temperatures and sampled over 25 or 28 days. After 21 days, the concentration of CTC in the 22, 38 and 55°C swine digester slurries decreased 7, 80 and 98%, respectively. Coliforms in the 22°C digester slurries were still viable after 25 days; however, they were not detectable in the 38 and 55°C slurries after 3 and 1 days, respectively. After 28 days, the concentration of MON in the 22, 38 and 55°C cattle digester slurries decreased 3, 8 and 27%, respectively. Coliforms in the 22°C cattle digester slurries were still viable after 28 days; however, they were not detectable in the 38 and 55°C slurries after 14 and 1 days, respectively. Conclusions: These studies indicate that anaerobic digestion at 38 or 55°C may be an effective treatment to reduce coliforms and CTC; however, it is not an effective treatment to reduce MON. Significance and Impact of the Study: More studies are needed to determine which pharmaceuticals are susceptible to degradation by a specific manure treatment to prevent negative environmental consequences.     

Effect of salinity on cable bacteria species composition and diversity

Cable bacteria (CB) are Desulfobulbaceae that couple sulphide oxidation to oxygen reduction over centimetre distances by mediating electric currents. Recently, it was suggested that the CB clade is composed of two genera, Ca. Electronema and Ca. Electrothrix, with distinct freshwater and marine habitats respectively. However, only a few studies have reported CB from freshwater sediment, making this distinction uncertain. Here, we report novel data to show that salinity is a controlling factor for the diversity and the species composition within CB populations. CB sampled from a freshwater site (salinity 0.3) grouped into Ca. Electronema and could not grow under brackish conditions (salinity 21), whereas CB from a brackish site (salinity 21) grouped into Ca. Electrothrix and decreased by 93% in activity under freshwater conditions. On a regional scale (Baltic Sea), salinity significantly influenced species richness and composition. However, other environmental factors, such as temperature and quantity and quality of organic matter were also important to explain the observed variation. A global survey of 16S rRNA gene amplicon sequencing revealed that the two genera did not co-occur likely because of competitive exclusion and identified a possible third genus.     

The effects of pesticides on the diversity of culturable soil bacteria

The numbers of culturable soil bacteria in plots that had received either no pesticides or the full combination (aldicarb, chlorfenvinphos, benomyl, glyphosate, plus chlorotoluron or triadimefon) over a 20 year period were compared. Differences were very small although there were consistently higher numbers on the treated plot, possibly reflecting the greater crop yields which had been reported previously. There was no significant difference in numbers of bacterial colonies with homology to a nif gene probe in soils from the two plots. Genetic fingerprinting of Pseudomonas fluorescens isolates from the plots, using ERIC-PCR, showed that the dominant strains in the two populations were not the same although there was no obvious difference in the degree of diversity. Substrate utilization by microbial populations from the two plots was compared using Biolog plates. The population from the pesticide-treated plot showed a higher rate of substrate utilization which could reflect a slightly higher inoculum of heterotrophic bacteria, but could also indicate greater metabolic diversity in the population.     

The diversity of culturable organotrophic bacteria from local solar salterns

We isolated and cultured bacteria inhabiting solar saltern ponds in Taean-Gun, Chungnam Province, Korea. All of the isolated 64 strains were found to be moderately halophilic bacteria, growing in a salt range of 2-20 %, with an optimal concentration of 5% salt. Bacterial diversity among the isolated halophiles was evaluated via RFLP analyses of PCR-amplified 16S rDNAs, followed by phylogenetic analysis of the partial 16S rDNA sequences. The combination of restriction enzyme digestions with HaeIII, CfoI, MspI and RsaI generated 54 distinct patterns. A neighbor-joining tree of the partial 16S rDNA sequences resulted in the division of the 64 strains into 2 major groups, 45 strains of gamma-Proteobacteria (70.3%) and 19 strains of Firmicutes (29.7%). The alpha-Proteobacteria and Cytophaga-Flavobacterium-Bacterioides groups, which were repeatedly found to exist in thalassohaline environments, were not represented in our isolates. The gamma-Proteobacteria group consisted of several subgroups of the Vibrionaceae (37.5%), Pseudoalteromonadaceae (10.9%), Halomonadaceae (7.8%), Alteromonadaceae (7.8%), and Idiomarinaceae (6.3%). Members of Salinivibrio costicola (29.7%) were the most predominant species among all of the isolates, followed by Halobacillus treperi (12.5%). Additionally, three new species candidates were found, based on similarities of the 16S rDNA sequences to those of previously published species.     

High diversity of culturable Burkholderia species associated with sugarcane

Sugarcane is an important crop around the world. Burkholderia genus has emerged as an important plant associated bacteria in the last years. In this study, the occurrence of Burkholderia species associated with two sugarcane varieties cultivated in Mexico was assessed. Burkholderia species were isolated with and without diazotrophs enrichment from sugarcane. Burkholderia strains were identified using a semi-selective set of primers and clustered by restriction analysis of 16S rRNA. The isolates were characterized by 16S rRNA, recA and nifH sequence analysis, whole-cell protein patterns, and plant-growth promotion (PGP) characteristics. Diazotrophic B. unamae and B. tropica were predominant using diazotroph enrichment method. Non-diazotrophic B. cepacia complex (Bcc) species were predominant without enrichment. Among non-diazotrophs, B. tropica was identified. The diazotrophic Burkholderia species exhibit in vitro PGP activities: biosynthesis of indolic compounds, phosphate solubilization, siderophores production and acdS gene presence, which encodes the enzyme ACC (1-aminocyclopropane-1-carboxylate) deaminase. The present study confirms the broad environmental and geographic distribution of diazotrophic B. unamae and B. tropica, and reveals the riches of Bcc and other Burkholderia species associated with sugarcane field-grown in Mexico. This work also shows the potential activities in PGP.     

Phylogenetic diversity of culturable bacteria from Antarctic sandy intertidal sediments

The diversity of culturable bacteria associated with sandy intertidal sediments from the coastal regions of the Chinese Antarctic Zhongshan Station on the Larsemann Hills (Princess Elizabeth Land, East Antarctica) was investigated. A total of 65 aerobic heterotrophic bacterial strains were isolated at 4°C. Microscopy and 16S rRNA gene sequence analysis indicated that the isolates were dominated by Gram-negative bacteria, while only 16 Gram-positive strains were isolated. The bacterial isolates fell in five phylogenetic groups: Alpha- and Gammaproteobacteria, Bacteroidetes, Actinobacteria and Firmicutes. Based on phylogenetic trees, all the 65 isolates were sorted into 29 main clusters, corresponding to at least 29 different genera. Based on sequence analysis (<98% sequence similarity), the Antarctic isolates belonged to at least 37 different bacterial species, and 14 of the 37 bacterial species (37.8%) represented potentially novel taxa. These results indicated a high culturable diversity within the bacterial community of the Antarctic sandy intertidal sediments.     

云南省富宁磁铁矿矿区可培养细菌多样性初步研究

目的对云南富宁磁铁矿矿区样品中可培养细菌进行分离并对其多样性进行了初步研究。方法采集云南富宁磁铁矿矿区土样和矿石样,采用固体肉汤培养基、卵黄培养基及PYGV培养基分离该矿区环境中的可培养细菌,利用16SrRNA基因序列分析构建系统发育树,并统计不同种属细菌的数量,初步评估细菌多样性。结果富宁磁铁矿矿区环境细菌的主要种群包括厚壁菌门、放线菌门和变形菌门的不同菌属：芽孢杆菌属、葡萄球菌属、节杆菌属和假单胞菌属的菌株,其中抗逆性较强的优势菌群为厚壁菌门的芽孢杆菌。结论本研究初步表明富宁磁铁矿矿区可培养细菌种类具有一定的多样性。     

Effect of temperature on bacterial species diversity in thermophilic solid-waste composting

Continuously thermophilic composting was examined with a 4.5-liter reactor placed in an incubator maintained at representative temperatures. Feed was a mixture of dried table scraps and shredded newspaper wetted to 55% moisture. One run at 49 degrees C (run A) employed a 1:4 feed-to-compost ratio, while the other runs used a 10:1 ratio and were incubated at 50, 55, 60, or 65 degrees C. Due to self-heating, internal temperatures of the composting mass were 0 to 7 degrees C hotter than the incubator. Two full-scale composting plants (at Altoona, Pa., and Leicester, England) were also examined. Plate counts per gram (dry weight) on Trypticase soy broth (BBL Microbiology Systems) with 2% agar ranged from 0.7 X 10(9) to 5.3 X 10(9) for laboratory composting and 0.02 X 10(9) to 7.4 X 10(9) for field composting. Fifteen taxa were isolated, including 10 of genus Bacillus, which dominated all samples except that from run A. Species diversity decreased markedly in laboratory composting at 60 degrees C and above, but was similar for the three runs incubated at 49, 50, and 55 degrees C. The maximum desirable composting temperature based on species diversity is thus 60 degrees C, the same as that previously recommended based on measures of the rate of decomposition.     

Traditional cattle manure application determines abundance, diversity and activity of methanogenic Archaea in arable European soil

Based on lipid analyses, 16S rRNA/rRNA gene single-strand conformation polymorphism fingerprints and methane flux measurements, influences of the fertilization regime on abundance and diversity of archaeal communities were investigated in soil samples from the long-term (103 years) field trial in Bad Lauchst?dt, Germany. The investigated plots followed a gradient of increasing fertilization beginning at no fertilization and ending at the 'cattle manure' itself. The archaeal phospholipid etherlipid (PLEL) concentration was used as an indicator for archaeal biomass and increased with the gradient of increasing fertilization, whereby the concentrations determined for organically fertilized soils were well above previously reported values. Methane emission, although at a low level, were occasionally only observed in organically fertilized soils, whereas the other treatments showed significant methane uptake. Euryarchaeotal organisms were abundant in all investigated samples but 16S rRNA analysis also demonstrated the presence of Crenarchaeota in fertilized soils. Lowest molecular archaeal diversity was found in highest fertilized treatments. Archaea phylogenetically most closely related to cultured methanogens were abundant in these fertilized soils, whereas Archaea with low relatedness to cultured microorganisms dominated in non-fertilized soils. Relatives of Methanoculleus spp. were found almost exclusively in organically fertilized soils or cattle manure. Methanosarcina-related microorganisms were detected in all soils as well as in the cattle manure, but soils with highest organic application rate were specifically dominated by a close phylogenetic relative of Methanosarcina thermophila. Our findings suggest that regular application of cattle manure increased archaeal biomass, but reduced archaeal diversity and selected for methanogenic Methanoculleus and Methanosarcina strains, leading to the circumstance that high organic fertilized soils did not function as a methane sink at the investigated site anymore.     

Deciphering the diversity of culturable thermotolerant bacteria from Manikaran hot springs

The aim of this study was to analyze and characterize the diversity of culturable thermotolerant bacteria in Manikaran hot springs. A total of 235 isolates were obtained employing different media, and screened for temperature tolerance (40 °C–70 °C). A set of 85 isolates tolerant to 45 °C or above were placed in 42 phylogenetic clusters after amplified ribosomal DNA restriction analysis (16S rRNA-ARDRA). Sequencing of the 16S rRNA gene of 42 representative isolates followed by BLAST search revealed that the majority of isolates belonged to Firmicutes, followed by equal representation of Actinobacteria and Proteobacteria. Screening of representative isolates (42 ARDRA phylotypes) for amylase activity revealed that 26 % of the isolates were positive, while 45 % exhibited protease activity, among which one amylase and six protease producers were tolerant up to 70 °C. BIOLOG-based identification of 13 isolates exhibiting temperature tolerance up to 70 °C, using carbon utilization patterns and sensitivity to chemicals, revealed a high degree of correlation with identification based on 16S rRNA gene sequencing for all isolates, except one (M48). These promising isolates showing a range of useful metabolic attributes demand to be explored further for industrial and agricultural applications.     

高温胁迫下两种藓类植物过氧化物酶活性的变化

在不同的高温胁迫条件下 ,对湿地匍灯藓 (Plagiomnium acutum)和大羽藓 (Thuidium cymbifolium)过氧化物酶 (POD)活性及其与处理时间和处理温度的关系进行了初步研究。结果表明 ,在一定的温度范围内 ,随着温度的升高 ,POD活性增加 ,二者成线形关系。在一定温度条件下 ,一般随着处理时间的延长 ,POD活性增加。但是当超过一定的温度 (4 5～ 5 0°C)以及一定的处理时间 (4～ 6h) ,POD活性有所下降。结果还表明 ,湿地匍灯藓的POD活性显著高于大羽藓。而且在高温胁迫下 ,湿地匍灯藓 POD活性变化比大羽藓活跃 ,其变化幅度也比大羽藓大。     

Effect of temperature on bacterial species diversity in thermophilic solid-waste composting.

Continuously thermophilic composting was examined with a 4.5-liter reactor placed in an incubator maintained at representative temperatures. Feed was a mixture of dried table scraps and shredded newspaper wetted to 55% moisture. One run at 49 degrees C (run A) employed a 1:4 feed-to-compost ratio, while the other runs used a 10:1 ratio and were incubated at 50, 55, 60, or 65 degrees C. Due to self-heating, internal temperatures of the composting mass were 0 to 7 degrees C hotter than the incubator. Two full-scale composting plants (at Altoona, Pa., and Leicester, England) were also examined. Plate counts per gram (dry weight) on Trypticase soy broth (BBL Microbiology Systems) with 2% agar ranged from 0.7 X 10(9) to 5.3 X 10(9) for laboratory composting and 0.02 X 10(9) to 7.4 X 10(9) for field composting. Fifteen taxa were isolated, including 10 of genus Bacillus, which dominated all samples except that from run A. Species diversity decreased markedly in laboratory composting at 60 degrees C and above, but was similar for the three runs incubated at 49, 50, and 55 degrees C. The maximum desirable composting temperature based on species diversity is thus 60 degrees C, the same as that previously recommended based on measures of the rate of decomposition.