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1.
Sadaharu Ui Hiroshi Masuda Hiroyuki Muraki 《Bioscience, biotechnology, and biochemistry》2013,77(11):2837-2838
Dark hydrogen production by a newly isolated marine green alga, Chlamydomonas MGA 161 was studied. This alga was a halotolerant, not a halophilic type, and grew well in both natural and artificial seawater media. From an experiment with cycloheximide addition, it was found that the hydrogenase reaction in this alga was not a rate-limiting step of dark hydrogen evolution. Starch accumulation increased at a low NH4Cl concentration (0.5 mm), at a low temperature (20°C), or at a high NaCl concentration (7%). Hydrogen evolution was correlated with starch degradation rather than starch accumulation, and the molar yield of hydrogen from starch-glucose was very high, at about 2 (mol H2/mol glucose). A comparison of the distribution pattern of fermentation products in various green algae, showed a unique fermentation pattern for Chlamydomonas MGA 161, with high hydrogen evolution but almost no formate. 相似文献
2.
In a mineral medium containing sulfate, the sulfate-reducing bacteriumDesulfovibrio sp. strain JJ degraded 1 mol of fructose stoichiometrically to 1 mol of H2S, 2 mol of acetate, and presumably 2 mol of CO2. The doubling time was 10 h, and the yield was 41.6 g dry weight/mol fructose degraded. In the absence of sulfate, the hydrogenophilic methanogenMethanospirillum hungatei replaced sulfate as hydrogen sink. In such cocultures, 1 mol of fructose was converted to acetate, methane, succinate, and presumably CO2 in varying concentrations. The growth yield of the H2-transferring association was 33 g dry weight/mol fructose. In the absence of sulfate,Desulfovibrio strain JJ slowly fermented 1 mol of fructose to 1 mol of succinate, 0.5 mol of acetate, and 0.5 mol of ethanol. The results are compared with those of other anaerobic hexose-degrading bacteria. 相似文献
3.
Hydrogen evolution as a consumption mode of reducing equivalents in green algal fermentation 总被引:2,自引:0,他引:2
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Dark anaerobic fermentation in the green algae Chlamydomonas MGA 161, Chlamydomonas reinhardtii, Chlorella pyrenoidosa, and Chlorococcum minutum was studied. Our isolate, Chlamydomonas MGA 161, was unusual in having high H2 but almost no formate. The fermentation pattern in Chlamydomonas MGA 161 was altered by changes in the NaCl or NH4Cl concentration. Glycerol formation increased at low (0.1%) and high (7%) NaCl concentrations; starch degradation, and formation of ethanol, H2, and CO2 increased with the addition of NH4Cl to above 5 millimolar in N-deficient cells. C. reinhardtii and C. pyrenoidosa exhibited a very similar anaerobic metabolism, forming formate, acetate and ethanol in a ratio of about 2:2:1. C. minutum was also unusual in forming acetate, glycerol, and CO2 as its main products, with H2, formate, and ethanol being formed in negligible amounts. In the presence of CO, ethanol formation increased twofold in Chlamydomonas MGA 161 and C. reinhardtii, but the fermentation pattern in C. minutum did not change. An experiment with hypophosphite addition showed that dark H2 evolution of the Escherichia coli type could be ruled out in Chlamydomonas MGA 161 and C. reinhardtii. Among the green algae investigated, three fermentation types were identified by the distribution pattern of the end products, which reflected the consumption mode of reducing equivalents in the cells. 相似文献
4.
Combined dark and photo-fermentation was carried out to study the feasibility of biological hydrogen production. In dark fermentation,
hydrogen was produced by Enterobacter cloacae strain DM11 using glucose as substrate. This was followed by a photo-fermentation process. Here, the spent medium from the
dark process (containing unconverted metabolites, mainly acetic acid etc.) underwent photo-fermentation by Rhodobacter sphaeroides strain O.U.001 in a column photo-bioreactor. This combination could achieve higher yields of hydrogen by complete utilization
of the chemical energy stored in the substrate. Dark fermentation was studied in terms of several process parameters, such
as initial substrate concentration, initial pH of the medium and temperature, to establish favorable conditions for maximum
hydrogen production. Also, the effects of the threshold concentration of acetic acid, light intensity and the presence of
additional nitrogen sources in the spent effluent on the amount of hydrogen produced during photo-fermentation were investigated.
The light conversion efficiency of hydrogen was found to be inversely proportional to the incident light intensity. In a batch
system, the yield of hydrogen in the dark fermentation was about 1.86 mol H2 mol−1 glucose; and the yield in the photo-fermentation was about 1.5–1.72 mol H2 mol−1 acetic acid. The overall yield of hydrogen in the combined process, considering glucose as the preliminary substrate, was
found to be higher than that in a single process. 相似文献
5.
The role of carbon dioxide in light-activated hydrogen production by Chlamydomonas reinhardtii 总被引:1,自引:0,他引:1
Light-activated hydrogen and oxygen evolution as a function of CO2 concentration in helium were measured for the unicellular green alga Chlamydomonas reinhardtii. The concentrations were 58, 30, 0.8 and 0 ppm CO2. The objective of these experiments was to study the differential affinity of CO2/HCO
3
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for their respective Photosystem II and Calvin cycle binding sites vis-à-vis photoevolution of molecular oxygen and the competitive pathways of hydrogen photoevolution and CO2 photoassimilation. The maximum rate of hydrogen evolution occurred at 0.8 ppm CO2, whereas the maximum rate of oxygen evolution occurred at 58 ppm CO2. The key result of this work is that the rate of photosynthetic hydrogen evolution can be increased by, at least partially, satisfying the Photosystem II CO2/HCO
3
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binding site requirement without fully activating the Calvin-Benson CO2 reduction pathway. Data are presented which plot the rates of hydrogen and oxygen evolution as functions of atmospheric CO2 concentration in helium and light intensity. The stoichiometric ratio of hydrogen to oxygen changed from 0.1 at 58 ppm to approximately 2.5 at 0.8 ppm. A discussion of partitioning of photosynthetic reductant between the hydrogen/hydrogenase and Calvin-Benson cycle pathways is presented.Abbreviations PET
photosynthetic electron transport
- PS
Photosystem 相似文献
6.
To isolate a salt tolerant hydrogen-producing bacterium, we used the sludge from the intertidal zone of a bathing beach in
Tianjin as inoculum to enrich hydrogen-producing bacteria. The sludge was treated by heat-shock pretreatment with three different
temperature (80, 100 and 121°C) respectively. A hydrogen-producing bacterium was isolated from the sludge pretreated at 80°C
by sandwich plate technique and identified using microscopic examination and 16S rDNA gene sequence analysis. The isolated
bacterium was named as Bacillus sp. B2. The present study examined the hydrogen-producing ability of Bacillus sp. B2. The strain was able to produce hydrogen over a wide range of initial pH from 5.0 to 10.0, with an optimum at pH 7.0.
The level of hydrogen production was also affected by the salt concentration. Strain B2 has unique capability to adapt high
salt concentration. It could produce hydrogen at the salt concentration from 4 to 60‰. The maximum of hydrogen-producing yield
of strain B2 was 1.65 ± 0.04 mol H2/mol glucose (mean ± SE) at an initial pH value of 7.0 in marine culture conditions. Hydrogen production under fresh culture
conditions reached a higher level than that in marine ones. As a result, it is likely that Bacillus sp. B2 could be applied to biohydrogen production using both marine and fresh organic waste. 相似文献
7.
Yoshida A Nishimura T Kawaguchi H Inui M Yukawa H 《Applied microbiology and biotechnology》2006,73(1):67-72
We improved the hydrogen yield from glucose using a genetically modified Escherichia coli. E. coli strain SR15 (ΔldhA, ΔfrdBC), in which glucose metabolism was directed to pyruvate formate lyase (PFL), was constructed. The hydrogen yield of wild-type strain of 1.08 mol/mol glucose, was enhanced to 1.82 mol/mol glucose in strain SR15. This figure is greater than 90 % of the theoretical hydrogen yield of facultative anaerobes (2.0 mol/mol glucose). Moreover, the specific hydrogen production rate of strain SR15 (13.4 mmol h−1 g−1 dry cell) was 1.4-fold higher than that of wild-type strain. In addition, the volumetric hydrogen production rate increased using the process where cells behaved as an effective catalyst. At 94.3 g dry cell/l, a productivity of 793 mmol h−1 l−1 (20.2 l h−1 l−1 at 37 °C) was achieved using SR15. The reported productivity substantially surpasses that of conventional biological hydrogen production processes and can be a trigger for practical applications. 相似文献
8.
Desulfovibrio vulgaris strain Madison outcompetedMethanobacterium strain ivanov for hydrogen when sulfate was in excess because of higher cell yield and growth rate and a greater affinity for hydrogen as a consequence of a lower Km and higher Vmax for in vivo hydrogenase activity.Desulfovibrio vulgaris displayed a growth yield of 1.1 g/mol H2, a Km for tritium exchange of 4 M, and a specific in vivo hydrogenase activity of 2.17 DPM3H2O×103/g cell protein/h; whereasMethanobacterium strain ivanov had a yield of 0.6 g/mol H2, a Km for tritium exchange of 14 M, and a specific in vivo hydrogenase activity of 0.38 DPM3H2O×103/g cell protein/h. Under these physiological conditions, the Gibbs free-energy change associated with methanogenesis and sulfidogenesis from H2 was calculated to be-47.4 kJ/mol and-62.9 kJ/mol, respectively. When sulfidogenesis was limited by sulfate concentration, the methanogen was able to successfully compete with the sulfidogen for hydrogen. Competition between methanogens and sulfidogens for hydrogen is explained in terms of thermodynamic, kinetic, and other important considerations not discussed in the previous literature. 相似文献
9.
Jody J Wright Keith Mewis Niels W Hanson Kishori M Konwar Kendra R Maas Steven J Hallam 《The ISME journal》2014,8(2):455-468
Marine Group A (MGA) is a deeply branching and uncultivated phylum of bacteria. Although their functional roles remain elusive, MGA subgroups are particularly abundant and diverse in oxygen minimum zones and permanent or seasonally stratified anoxic basins, suggesting metabolic adaptation to oxygen-deficiency. Here, we expand a previous survey of MGA diversity in O2-deficient waters of the Northeast subarctic Pacific Ocean (NESAP) to include Saanich Inlet (SI), an anoxic fjord with seasonal O2 gradients and periodic sulfide accumulation. Phylogenetic analysis of small subunit ribosomal RNA (16S rRNA) gene clone libraries recovered five previously described MGA subgroups and defined three novel subgroups (SHBH1141, SHBH391, and SHAN400) in SI. To discern the functional properties of MGA residing along gradients of O2 in the NESAP and SI, we identified and sequenced to completion 14 fosmids harboring MGA-associated 16S RNA genes from a collection of 46 fosmid libraries sourced from NESAP and SI waters. Comparative analysis of these fosmids, in addition to four publicly available MGA-associated large-insert DNA fragments from Hawaii Ocean Time-series and Monterey Bay, revealed widespread genomic differentiation proximal to the ribosomal RNA operon that did not consistently reflect subgroup partitioning patterns observed in 16S rRNA gene clone libraries. Predicted protein-coding genes associated with adaptation to O2-deficiency and sulfur-based energy metabolism were detected on multiple fosmids, including polysulfide reductase (psrABC), implicated in dissimilatory polysulfide reduction to hydrogen sulfide and dissimilatory sulfur oxidation. These results posit a potential role for specific MGA subgroups in the marine sulfur cycle. 相似文献
10.
Composition of the mixed culture was varied in combined dark-light fermentation of wheat powder starch in order to improve
hydrogen gas formation rate and yield. Heat-treated anaerobic sludge and pure culture of Clostridium beijerinckii (DSMZ 791
T
) were combined with two different light fermentation bacteria of Rhodobacter sphaeroides (RS-NRRL and RS-RV) in order to select a more suitable mixture resulting in high hydrogen yield and formation rate. A combination
of the anaerobic sludge and RS-NRRL yielded the highest cumulative hydrogen (CHF = 140 ml), the highest yield (0.36 mol H2 mol−1 glucose) and specific hydrogen formation rate (2.5 ml H2 g−1 biomass h−1). During dark fermentation (70 h) hydrogen was produced simultaneously by the dark and light fermentation bacteria using
glucose from hydrolyzed starch. However, only light fermentation bacteria produced hydrogen from VFA’s derived from dark fermentation
after a long adaptation period. 相似文献
11.
Bernardina L. M. Van Kuijk Elvire Schlösser Alfons J. M. Stams 《Archives of microbiology》1998,169(4):346-352
The growth of the syntrophic propionate-oxidizing bacterium strain MPOB in pure culture by fumarate disproportionation into
carbon dioxide and succinate and by fumarate reduction with propionate, formate or hydrogen as electron donor was studied.
The highest growth yield, 12.2 g dry cells/mol fumarate, was observed for growth by fumarate disproportionation. In the presence
of hydrogen, formate or propionate, the growth yield was more than twice as low: 4.8, 4.6, and 5.2 g dry cells/mol fumarate,
respectively. The location of enzymes that are involved in the electron transport chain during fumarate reduction in strain
MPOB was analyzed. Fumarate reductase, succinate dehydrogenase, and ATPase were membrane-bound, while formate dehydrogenase
and hydrogenase were loosely attached to the periplasmic side of the membrane. The cells contained cytochrome c, cytochrome b, menaquinone-6 and menaquinone-7 as possible electron carriers. Fumarate reduction with hydrogen in membranes of strain MPOB
was inhibited by 2-(heptyl)-4-hydroxyquinoline-N-oxide (HOQNO). This inhibition, together with the activity of fumarate reductase with reduced 2,3-dimethyl-1,4-naphtoquinone
(DMNH2) and the observation that cytochrome b of strain MPOB was oxidized by fumarate, suggested that menequinone and cytochrome b are involved in the electron transport during fumarate reduction in strain MPOB. The growth yields of fumarate reduction
with hydrogen or formate as electron donor were similar to the growth yield of Wolinella succinogenes. Therefore, it can be assumed that strain MPOB gains the same amount of ATP from fumarate reduction as W. succinogenes, i.e. 0.7 mol ATP/mol fumarate. This value supports the hypothesis that syntrophic propionate-oxidizing bacteria have to
invest two-thirds of an ATP via reversed electron transport in the succinate oxidation step during the oxidation of propionate.
The same electron transport chain that is involved in fumarate reduction may operate in the reversed direction to drive the
energetically unfavourable oxidation of succinate during syntrophic propionate oxidation since (1) cytochrome b was reduced by succinate and (2) succinate oxidation was similarly inhibited by HOQNO as fumarate reduction.
Received: 18 March 1997 / Accepted: 10 November 1997 相似文献
12.
Bradley E. Jackson V. K. Bhupathiraju Ralph S. Tanner Carl R. Woese M. J. McInerney 《Archives of microbiology》1999,171(2):107-114
Strain SBT is a new, strictly anaerobic, gram-negative, nonmotile, non-sporeforming, rod-shaped bacterium that degrades benzoate and
certain fatty acids in syntrophic association with hydrogen/formate-using microorganisms. Strain SBT produced approximately 3 mol of acetate and 0.6 mol of methane per mol of benzoate in coculture with Methanospirillum hungatei strain JF1. Saturated fatty acids, some unsaturated fatty acids, and methyl esters of butyrate and hexanoate also supported
growth of strain SBT in coculture with Desulfovibrio strain G11. Strain SBT grew in pure culture with crotonate, producing acetate, butyrate, caproate, and hydrogen. The molar growth yield was 17 ±
1 g cell dry mass per mol of crotonate. Strain SBT did not grow with fumarate, iron(III), polysulfide, or oxyanions of sulfur or nitrogen as electron acceptors with benzoate
as the electron donor. The DNA base composition of strain SBT was 43.1 mol% G+C. Analysis of the 16 S rRNA gene sequence placed strain SBT in the δ-subdivision of the Proteobacteria, with sulfate-reducing bacteria. Strain SBT was most closely related to members of the genus Syntrophus. The clear phenotypic and genotypic differences between strain SBT and the two described species in the genus Syntrophus justify the formation of a new species, Syntrophus aciditrophicus.
Received: 2 June 1998 / Accepted: 16 November 1998 相似文献
13.
A strictly anaerobic, benzoate-degrading bacterium,Syntrophus buswellii strain GA, was able to degrade benzoate or 3-phenylpropionate to acetate, CO2 and H2 if the hydrogen partial pressure was sufficiently low. The hydrogen was removed in syntrophic coculture byMethanospirillum hungatei or byDesulfovibrio sp. through interspecies hydrogen transfer or in pure culture by the use of crotonate as reducible cosubstrate. Alternatively,S. buswellii strain GA could grow in pure culture with crotonate. Activities of seven catabolic enzymes were measured in crude cell extracts ofS. buswellii strain GA grown with various substrates and of crotonate-grownS. buswellii strain DSM 2612A. Benzoate, 3-phenylpropionate and crotonate were activated by CoA ligases. Glutaryl-CoA dehydrogenase was found to be involved in the degradation of aromatic compounds and enzymes catalysing -oxidation were involved in the reaction sequence from crotonyl-CoA to acetate. Ac-type cytochrome was present in the cytoplasm, whereasb-type cytochromes were associated with the membranes of bothS. buswelli strains grown on crotonate. These indicated the presence of an electron-transport system. A high growth yield of crotonate-grownS. buswellii strain GA might be explained by electron-transport phosphorylation in addition to substrate-level phosphorylation. 相似文献
14.
Comparative Amperometric Study of Uptake Hydrogenase and Hydrogen Photoproduction Activities between Heterocystous Cyanobacterium Anabaena cylindrica B629 and Nonheterocystous Cyanobacterium Oscillatoria sp. Strain Miami BG7 总被引:3,自引:1,他引:2
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Heterocystous filamentous cyanobacterium Anabaena cylindrica B629 and nonheterocystous filamentous cyanobacterium Oscillatoria sp. strain Miami BG7 were cultured in media with N2 as the sole nitrogen source; and activities of oxygen-dependent hydrogen uptake, photohydrogen production, photooxygen evolution, and respiration were compared amperometrically under the same or similar experimental conditions for both strains. Distinct differences in these activities were observed in both strains. The rates of hydrogen photoproduction and hydrogen accumulation were significantly higher in Oscillatoria sp. strain BG7 than in A. cylindrica B629 at every light intensity tested. The major reason for the difference was attributable to the fact that the heterocystous cyanobacterium had a high rate of oxygen-dependent hydrogen consumption activity and the nonheterocystous cyanobacterium did not. The activity of oxygen photoevolution and respiration also contributed to the difference. Oscillatoria sp. strain BG7 had lower O2 evolution and higher respiration than did A. cylindrica B629. Thus, the effect of O2 on hydrogen photoproduction was minimized in Oscillatoria sp. strain BG7. 相似文献
15.
A fermentative hydrogen-producing strain, RZF-1108, was isolated from a biohydrogen reactor, and identified as Clostridium beijerinckii on the basis of the 16S rRNA gene analysis and physiobiochemical characteristics. The effects of culture conditions on hydrogen production by C. beijerinckii RZF-1108 were investigated in batch cultures. The hydrogen production and growth of strain RZF-1108 were highly dependent on temperature, initial pH and substrate concentration. Yeast extract was a favorable nitrogen source for hydrogen production and growth of RZF-1108. Hydrogen production corresponded to cell biomass yield in different culture conditions. The maximum hydrogen evolution, yield and production rate of 2209 ml H2/l medium, 1.97 mol H2/mol glucose and 104.20 ml H2/g CDW h−1 were obtained at 9 g/l of glucose, initial pH of 7.0, inoculum volume of 8% and temperature of 35 °C, respectively. These results demonstrate that C. beijerinckii can efficiently produce H2, and is another model microorganism for biohydrogen investigations. 相似文献
16.
Growth yields were determined with Acetobacterium woodii strain NZva 16 on hydrogen and CO2, formate, methanol, vanillate, ferulate and fructose in mineral medium in the absence and presence of 0.05% yeast extract. Yeast extract was not essential for growth but enhanced growth yields by 25–100% depending on the substrate fermented. Comparison of yields on formate or methanol allowed calculation of an energy yield in the range of 1.5–2 mol ATP per mol acetate formed during homoacetate fermentation of A. woodii. In the presence of 6 mM caffeate, growth yields were determined with the substrates formate or methanol. Caffeate was reduced to hydrocaffeate and increased growth yields were obtained. An ATP yield of about 1 mol per mol of caffeate reduced was calculated. Cytochromes were not detectable in cell free extracts or membrane preparations. 相似文献
17.
Localization of the Enzymes Involved in the Photoevolution of H(2) from Acetate in Chlamydomonas reinhardtii 总被引:6,自引:5,他引:1
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The localization of a series of enzymes involved in the anaerobic photodissimilation of acetate in Chlamydomonas reinhardtii F-60 adapted to a hydrogen metabolism was determined through the enzymic analyses of the chloroplastic, cytoplasmic, and mitochondrial fractions obtained with a cellular fractionation procedure that incorporated cell wall removal by treatment with autolysine, digestion of the plasmalemma with the detergent digitonin, and fractionation by differential centrifugation on a Percoll step gradient. The sequence of events leading to the photoevolution of H2 from acetate includes the conversion of acetate into succinate via the extraplastidic glyoxylate cycle, the oxidation of succinate to fumarate by chloroplastic succinate dehydrogenase, and the oxidation of malate to oxaloacetate in the chloroplast by NAD dependent malate dehydrogenase. The level of potential activity for the enzymes assayed were sufficient to accommodate the observed rate of the photoanaerobic dissimilation of acetate and the photoevolution of H2. 相似文献
18.
Y. Lu J. Wang Z. Deng H. Wu Q. Deng H. Tan L. Cao 《Letters in applied microbiology》2013,57(3):200-205
An actinomycete producing oil‐like mixtures was isolated and characterized. The strain was isolated from sheep faeces and identified as Streptomyces sp. S161 based on 16S rRNA gene sequence analysis. The strain showed cellulase and xylanase activities. The 1H nuclear magnetic resonance (NMR) spectra of the mixtures showed that the mixtures were composed of fatty acid methyl esters (52·5), triglycerides (13·7) and monoglycerides (9·1) (mol.%). Based on the gas chromatography–mass spectrometry (GC‐MS) analysis, the fatty acid methyl esters were mainly composed of C14‐C16 long‐chain fatty acids. The results indicated that Streptomyces sp. S161 could produce fatty acid methyl esters (FAME) directly from starch. To our knowledge, this is the first isolated strain that can produce biodiesel (FAME) directly from starch.
Significance and Impact of the Study
Nowadays, production of biodiesel is based on plant oils, animal fats, algal oils and microbial oils. Lipid mostly consists of triacylglycerols (TAG), and conversion of these lipids into fatty acid short‐chain alcohol esters (methanol or ethanol) is the final step in biodiesel production. In this study, an oil‐producing Streptomyces strain was isolated from sheep faeces. The oil was composed of C14‐C16 long‐chain fatty acid methyl esters, triglycerides and monoglycerides. This is the first isolated strain‐producing biodiesel (FAME) directly from starch. Due to showing cellulase and xylanase activities, the strain would be helpful for converting renewable lignocellulose into biodiesel directly. 相似文献19.
Fermentation conditions (e.g., pressure and medium) are well-documented to impact the yield of microbial products in bioreactors. In this study we used
carefully controlled batch fermentations to characterize hydrogen production from engineered strains of Escherichia coli and developed a rapid method of inducing hydrogen production in previously aerobically grown cells by using a rich defined
medium. Our results indicated that rich defined media activated hydrogen production from aerobic pre-cultures with no lag
time and yielded more hydrogen and biomass than the commonly used minimal media. Under these conditions, deletion of both
uptake hydrogenase 1 (ΔhyaAB) and hydrogenase 2 (ΔhybABC) was shown to increase hydrogen yield from glucose by 10% over the wildtype strain BW25113. However, the deletion of the
repressor for the formate-hydrogen-lyase (FHL-1) complex (ΔhycA) did not further increase hydrogen production. Additional deletion of lactate dehydrogenase (ldhA) and fumarate reductase (frdBC) of the mixed-acid fermentation pathway increased hydrogen yield by 22 and 23%, respectively. Interestingly, combined elimination
of ldhA and frdBC in the uptake and hycA null strain increased hydrogen yield from 1.37 to 1.82 mol/mol glucose, obtaining 91% of the theoretical maximum hydrogen
yield. Our results indicated the advantage of using rich defined media for inducing hydrogen production. This study represents
the first report of characterizing metabolically engineered E. coli strains in batch hydrogen fermentation using rich defined media under tightly controlled conditions. 相似文献
20.
Aims: Applying competitive exclusion micro‐organisms to control hydrogen sulfide (H2S) gas produced by hydrogen sulfide–producing bacteria (SPB) in chicken meat. Methods and Results: Five SPB strains, isolated from animal by‐products, were used for screening lactic acid bacteria (LAB) that can inhibit the production of H2S by SPB in trypticase soy broth supplemented with l ‐cysteine (TSB‐l ‐cys). A sensitive and accurate test strip method was developed for H2S determination in real time. One LAB strain, isolate L86, from cheese whey, demonstrated the highest inhibitory activity against the production of H2S by SPB. The isolate L86 was confirmed as Enterococcus faecium that does not possess genes encoding for vancomycin resistance based on PCR analysis. Enterococcus faecium strain L86 reduced (P < 0·05) the yield of H2S upto 51·2% in 10 h at 35°C in TSB‐l ‐cys medium. In fresh chicken meat, the yield of H2S produced by the artificially inoculated SPB was reduced (P < 0·05) by 48·6, 49·7 and 69·8% in 10 h at 35, 30 and 25°C, respectively. Enterococcus faecium strain L86 also reduced (P < 0·05) by 53·8% on the yield of H2S produced by the indigenous SPB in partially spoiled chicken meat at 35°C for 10 h. Conclusions: Enterococcus faecium strain L86 is effective on inhibiting the production of H2S by SPB. Significance and Impact of the Study: The application of this biological agent to raw animal by‐products will provide a safer working environment in rendering processing plants and produce higher‐quality rendered products. 相似文献