Food allergy is a significant public health concern globally.Certain probiotics have been found to enhance food allergy by regulating immune-microbe interactions in animal models and patients.However,the effects of Bi...Food allergy is a significant public health concern globally.Certain probiotics have been found to enhance food allergy by regulating immune-microbe interactions in animal models and patients.However,the effects of Bifidobacterium lactis Probio-M8 on food allergy have not been thoroughly investigated.The present study examined the anti-allergic properties of Probio-M8,particularly in relation to immune response and gut microbiota composition.Results demonstrate that oral administration of Probio-M8 effectively mitigated the allergy symptoms triggered by ovalbumin(OVA)by ameliorating the morphological damage in the jejunum,reducing OVA-specific IgE and histamine levels in the serum,and suppressing Th2 cytokines(interleukin(IL)4 and IL-13)while increasing Th1 cytokines(interferon(IFN)γ)and regulatory T(Treg)cytokines(IL-10 and transforming growth factor(TGF)β1)in the culture supernatants of splenic cells.Furthermore,Probio-M8 effectively altered the diversity and composition of gut microbiota,particularly the relative abundances of Akkermansia_muciniphila in OVA-induced mice.Compared to the OVA group,the Probio-M8 group showed a decrease in the relative abundance of Akkermansia_muciniphila.In conclusion,Probio-M8 demonstrates the potential to alleviate food allergy by regulating the Th1/Th2 response and modulating gut microbiota,thereby offering a novel therapeutic strategy for patients with food allergy.展开更多
[Objective]The aim was to clone TapⅡchalcone isomerases（CHI1 A） from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone i...[Objective]The aim was to clone TapⅡchalcone isomerases（CHI1 A） from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone isomerases（CHI1 A） was cloned by RTPCR method,and it was sequenced after cloning into pMD18-T vectors,and recombined to expression vector PNZ8149-CHI1 A,then it was transformed into Lactococcus Lactis NZ3900[Result]The sequencing results indicated that the cloned fragment of CHI1 A contained 670 nucleotides,and shared a sequence homology of 92% with that from Genbank accession number AF595413（CHI1 A）.CHI1 A was transformed into NICE expression system successfully by identification of PCR and digestion.[Conclusion]The foundation of using the microorganism fermentation method to produce flavonoids was laid by construction of efficient induction expression vector with chalcone isomerases CHI1 A.展开更多
[Objective]In order to improve expression vector of L.lactis at food grade and widen application range of original system.[Method] Taking pNZ8149 as basis,the promoter PnisA of pNZ8149 was inserted L.lactis MG1363 and...[Objective]In order to improve expression vector of L.lactis at food grade and widen application range of original system.[Method] Taking pNZ8149 as basis,the promoter PnisA of pNZ8149 was inserted L.lactis MG1363 and SPusp45 of unknown secretory protein in downstream.Through PCR technology,specific primers were used to delete restriction sites between promoter sequence and signal peptide gene sequence and ensure better distance between SD sequence and start codon to construct secreting expression vector pNZS.The reporter gene gus was recombined into multiple cloning site of pNZS to construct pNZS-gus and L.lactis was transformed by electroporation.10 ng/ml nisin was used for induction culture,then culture solution was conducted GUS staining test.[Result]The new constructed L.lactis N3900/pNZS-gus system could express active GUS protein and GUS protein could be secreted out of cell.[Conclusion]The successful construction of this system lays foundation for secretion expression study of protein and oral vaccine research.展开更多
AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipati...AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipation were randomly allocated to consume for 2 wk either 100 g of the test fermented milk or 100 g of an acidified milk containing non-living bacteria (control).Stool frequency,defecation condition scores,stool consistency and food intake were recorded at baseline and after 1 and 2 wk in an intention-to-treat population of 126 subjects.In parallel,safety evaluation parameters were performed.RESULTS: At baseline,no differences were found between groups.Following consumption of test product,stool frequency was significantly increased after 1 wk (3.5 ± 1.5 vs 2.4 ± 0.6,P < 0.01) and 2 wk (4.1 ± 1.7 vs 2.4 ± 0.6,P < 0.01),vs baseline.Similarly,after 1 and 2 wk,of test product consumption,defecation condition (1.1 ± 0.9 vs 1.9 ± 1.2,P < 0.01 and 0.8 ± 1.0 vs 1.9 ± 1.2,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.5 ± 1.1,P < 0.01 and 0.6 ± 0.8 vs 1.5 ± 1.1,P < 0.01,respectively) were significantly improved.Compared with the control group,stool frequency was also significantly increased (3.5 ± 1.5 vs 2.5 ± 0.9,P < 0.01 and 4.1 ± 1.7 vs 2.6 ± 1.0,P < 0.01,respectively),and defecation condition (1.1 ± 0.9 vs 1.6 ± 1.1,P < 0.01 and 0.8 ± 1.0 vs 1.6 ± 1.1,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.4 ± 1.0,P < 0.05 and 0.6 ± 0.8 vs 1.3 ± 1.0,P < 0.01,respectively) significantly decreased after 1 and 2 wk of product consumption.During the same period,food intake did not change between the two groups,and safety parameters of the subjects were within normal ranges.CONCLUSION: This study suggests a beneficial effect of a fermented milk containing B.lactis DN-173010 on stool frequency,defecation condition and stool consistency in adult women with constipation constipated women after 1 and 2 wk of consumption.展开更多
Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion....Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion. Methods The gene fragments encoding β-galactosidase from two strains of Loctobacillus bulgaricus, wch9901 isolated from yogurt and 1.1480 purchased from the Chinese Academy of Sciences, were amplified and inserted into lactococcal expression vector pMG36e. For fusion expression, the open reading frame of the β-galactosidase gene was amplified, while for non-fusion expression, the open reading frame of the β-galactosidase gene was amplified with its native Shine-Dalgarno sequence upstream. The start codon of the β-galactosidase gene partially overlapped with the stop codon of vector origin open reading frame. Then, the recombinant plasmids were transformed into Escherichia coli DH5α and Lactococcus lactis subsp, lactis MG1363 and confirmed by determining β-galactosidase activities. Results The non-fusion expression plasmids showed a significantly higher β-galactosidase activity in transformed strains than the fusion expression plasmids. The highest enzyme activity was observed in Lactococcus lactis transformed with the non-fusion expression plasmids which were inserted into the β-galactosidase gene from Lactobacillus bulgaricus wch9901. The β-galactosidase activity was 2.75 times as high as that of the native counterpart. In addition, β-galactosidase expressed by recombinant plasmids in Lactococcus lactis could be secreted into the culture medium. The highest secretion rate （27.1%） was observed when the culture medium contained 20 g/L of lactose. Conclusion Different properties of the native bacteria may have some effects on the protein expression of recombinant plasmids. Non-fusion expression shows a higher enzyme activity in host bacteria. There may be a host-related weak secretion signal peptide gene within the structure gene of Lb. bulgaricus β-galactosidase, and its translation product may introduce the enzyme secretion out of cells in special hosts.展开更多
Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant pl...Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant plasmid pMG36e-usp-lacZ.This recombinant plasmid was transformed into both Escherichia coli DH5α and L.lactis MG1363.The enzyme activity,gene sequencing,SDS-PAGE and hereditary stability were assessed and studied.Results The lacZ gene inserted into plasmids pMG36e-usp-lacZ was 99.37% similar to the GenBank sequence,and SDS-PAGE revealed an evident idio-strap at 116 KDa between L.lactis MG1363/pMG36eusp-lacZ in both supernatant and cell samples.β-Galactosidase activity measured 0.225 U/mL in L.lactis pMG36e-usp-lacZ transformants,and its secretion rate was 10%.The plasmid pMG36e-usp-lacZ appeared more stable in MG1363.Conclusion The authors concluded that these new recombinant bacteria well expressed and secreted β-galactosidase,indicating that the β-galactosidase expression system was successfully constructed,and this might provide a new solution for management of lactose intolerance specifically and promote the use of gene-modified organisms as part of the food-grade plasmid in general.展开更多
AIM： To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS： The C-terminal 19-ku fragments of MSP1 （MSP-119） of Plasmodium yoelii265-BY was expressed in L. lactis and...AIM： To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS： The C-terminal 19-ku fragments of MSP1 （MSP-119） of Plasmodium yoelii265-BY was expressed in L. lactis and the recombinant L. lact/s was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythroo/tic stage. The protective efficacy of recombinant L. lactiswas evaluated. RESULTS： The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8± 0.4% and 20.8±26.5%, respectively, and those of their control groups were 12.0±0.8% and 60.8±9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. CONCLUSION： The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.展开更多
The autolysis and proteolysis are important features in the strains of L. lactis used in the manufacture of cheese. The autolytic and proteolytic activity of L. lactis has been linked with the development of flavor an...The autolysis and proteolysis are important features in the strains of L. lactis used in the manufacture of cheese. The autolytic and proteolytic activity of L. lactis has been linked with the development of flavor and texture in the cheese. On the other hand, there is a growing interest in new strains isolated from raw-milk cheeses and vegetables. These wild-strains have showed different features of industrial importance in comparison with those observed in commercial cultures. However, it still not clear if the autolytic and proteolytic properties of these wild-strains differ from the industrial strains. The objective of this work was to assess the autolytic and proteolytic activities of 21 strains of L. lactis isolated from diverse sources. The rates of autolysis and proteolysis observed in vitro were highly strain-dependent. The pH and the NaCl concentration in the media affected significantly the autolysis of L. lactis. The strains isolated from vegetable showed in general low and medium autolytic activity, whereas the strains isolated from raw-milk cheeses had medium to high autolytic activity. The strain with highest proteolytic activity was a strain isolated from corn leaves. Although still not clear how this strain acquired this pronounced characteristic.展开更多
To evaluate the specific immune responses induced by recombinant Lactococcus lactis（L.lactis） which expresses porcine epidemic diarrhea virus（PEDV） S1 protein through oral administration,the spike gene fragment of...To evaluate the specific immune responses induced by recombinant Lactococcus lactis（L.lactis） which expresses porcine epidemic diarrhea virus（PEDV） S1 protein through oral administration,the spike gene fragment of PEDV was amplified from PEDV SDLY strain to construct p MG36 e-S1 recombinant plasmid.The recombinant plasmid was then electro-transferred into competent cells of L.lactis MG1363,to prepare the recombinant L.lactis expressing S1 protein of PEDV.The expression of target protein was identified by SDS-PAGE and Western-blot.New Zealand white rabbits were orally administered with the recombinant strain;the antibody titer in intestinal mucosa and serum was detected by neutralizing test;and the specific Ig G in serum was evaluated by indirect ELISA.The results showed that the recombinant L.lactis could effectively induce high level of Ig G in serum and high level of mucosal immune antibody.The recombinant L.lactis is qualified to be a potential oral vaccine because it could successfully stimulate both humoral and mucosal immune responses against PEDV.展开更多
AIM: To investigate whether composite yogurt with acacia dietary fiber and Bifidobacterium lactis (B. lactis) has additive effects in irritable bowel syndrome (IBS). METHODS: A total of 130 patients were randomly allo...AIM: To investigate whether composite yogurt with acacia dietary fiber and Bifidobacterium lactis (B. lactis) has additive effects in irritable bowel syndrome (IBS). METHODS: A total of 130 patients were randomly allocated to consume, twice daily for 8 wk, either the composite yogurt or the control product. The composite yogurt contained acacia dietary fiber and high-dose B. lactis together with two classic yogurt starter cultures. Patients were evaluated using the visual analogscale via a structured questionnaire administered at baseline and after treatment. RESULTS: Improvements in bowel habit satisfaction and overall IBS symptoms from baseline were significantly higher in the test group than in the control group (27.16 vs 15.51, P = 0.010, 64.2 ± 17.0 vs 50.4 ± 20.5, P < 0.001; respectively). In constipation-predominant IBS, improvement in overall IBS symptoms was significantly higher in the test group than in the control group (72.4 ± 18.4 vs 50.0 ± 21.8, P < 0.001). In patients with diarrhea-predominant IBS, improvement in bowel habit satisfaction from baseline was significantly higher in the test group than in the control group (32.90 vs 7.81, P = 0.006). CONCLUSION: Our data suggest that composite yogurt enriched with acacia fiber and B. lactis has greater therapeutic effects in patients with IBS than standard yogurt.展开更多
基金the financial supporting by the National Key Research and Development Program of China(2022YFF1102400)National Natural Science Foundation of China(32102093)the Natural Science Foundation of Jiangsu Province(BK20210226)。
文摘Food allergy is a significant public health concern globally.Certain probiotics have been found to enhance food allergy by regulating immune-microbe interactions in animal models and patients.However,the effects of Bifidobacterium lactis Probio-M8 on food allergy have not been thoroughly investigated.The present study examined the anti-allergic properties of Probio-M8,particularly in relation to immune response and gut microbiota composition.Results demonstrate that oral administration of Probio-M8 effectively mitigated the allergy symptoms triggered by ovalbumin(OVA)by ameliorating the morphological damage in the jejunum,reducing OVA-specific IgE and histamine levels in the serum,and suppressing Th2 cytokines(interleukin(IL)4 and IL-13)while increasing Th1 cytokines(interferon(IFN)γ)and regulatory T(Treg)cytokines(IL-10 and transforming growth factor(TGF)β1)in the culture supernatants of splenic cells.Furthermore,Probio-M8 effectively altered the diversity and composition of gut microbiota,particularly the relative abundances of Akkermansia_muciniphila in OVA-induced mice.Compared to the OVA group,the Probio-M8 group showed a decrease in the relative abundance of Akkermansia_muciniphila.In conclusion,Probio-M8 demonstrates the potential to alleviate food allergy by regulating the Th1/Th2 response and modulating gut microbiota,thereby offering a novel therapeutic strategy for patients with food allergy.
文摘[Objective]The aim was to clone TapⅡchalcone isomerases（CHI1 A） from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone isomerases（CHI1 A） was cloned by RTPCR method,and it was sequenced after cloning into pMD18-T vectors,and recombined to expression vector PNZ8149-CHI1 A,then it was transformed into Lactococcus Lactis NZ3900[Result]The sequencing results indicated that the cloned fragment of CHI1 A contained 670 nucleotides,and shared a sequence homology of 92% with that from Genbank accession number AF595413（CHI1 A）.CHI1 A was transformed into NICE expression system successfully by identification of PCR and digestion.[Conclusion]The foundation of using the microorganism fermentation method to produce flavonoids was laid by construction of efficient induction expression vector with chalcone isomerases CHI1 A.
基金Supported by Doctoral Fund of Jilin Agricultural University(20070193005)~~
文摘[Objective]In order to improve expression vector of L.lactis at food grade and widen application range of original system.[Method] Taking pNZ8149 as basis,the promoter PnisA of pNZ8149 was inserted L.lactis MG1363 and SPusp45 of unknown secretory protein in downstream.Through PCR technology,specific primers were used to delete restriction sites between promoter sequence and signal peptide gene sequence and ensure better distance between SD sequence and start codon to construct secreting expression vector pNZS.The reporter gene gus was recombined into multiple cloning site of pNZS to construct pNZS-gus and L.lactis was transformed by electroporation.10 ng/ml nisin was used for induction culture,then culture solution was conducted GUS staining test.[Result]The new constructed L.lactis N3900/pNZS-gus system could express active GUS protein and GUS protein could be secreted out of cell.[Conclusion]The successful construction of this system lays foundation for secretion expression study of protein and oral vaccine research.
基金Danone (Shanghai) Consulting Co.Ltd115 national science and technology program
文摘AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipation were randomly allocated to consume for 2 wk either 100 g of the test fermented milk or 100 g of an acidified milk containing non-living bacteria (control).Stool frequency,defecation condition scores,stool consistency and food intake were recorded at baseline and after 1 and 2 wk in an intention-to-treat population of 126 subjects.In parallel,safety evaluation parameters were performed.RESULTS: At baseline,no differences were found between groups.Following consumption of test product,stool frequency was significantly increased after 1 wk (3.5 ± 1.5 vs 2.4 ± 0.6,P < 0.01) and 2 wk (4.1 ± 1.7 vs 2.4 ± 0.6,P < 0.01),vs baseline.Similarly,after 1 and 2 wk,of test product consumption,defecation condition (1.1 ± 0.9 vs 1.9 ± 1.2,P < 0.01 and 0.8 ± 1.0 vs 1.9 ± 1.2,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.5 ± 1.1,P < 0.01 and 0.6 ± 0.8 vs 1.5 ± 1.1,P < 0.01,respectively) were significantly improved.Compared with the control group,stool frequency was also significantly increased (3.5 ± 1.5 vs 2.5 ± 0.9,P < 0.01 and 4.1 ± 1.7 vs 2.6 ± 1.0,P < 0.01,respectively),and defecation condition (1.1 ± 0.9 vs 1.6 ± 1.1,P < 0.01 and 0.8 ± 1.0 vs 1.6 ± 1.1,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.4 ± 1.0,P < 0.05 and 0.6 ± 0.8 vs 1.3 ± 1.0,P < 0.01,respectively) significantly decreased after 1 and 2 wk of product consumption.During the same period,food intake did not change between the two groups,and safety parameters of the subjects were within normal ranges.CONCLUSION: This study suggests a beneficial effect of a fermented milk containing B.lactis DN-173010 on stool frequency,defecation condition and stool consistency in adult women with constipation constipated women after 1 and 2 wk of consumption.
基金a scientific research grant from Health Bureau of Sichuan Province (No. F0201)
文摘Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion. Methods The gene fragments encoding β-galactosidase from two strains of Loctobacillus bulgaricus, wch9901 isolated from yogurt and 1.1480 purchased from the Chinese Academy of Sciences, were amplified and inserted into lactococcal expression vector pMG36e. For fusion expression, the open reading frame of the β-galactosidase gene was amplified, while for non-fusion expression, the open reading frame of the β-galactosidase gene was amplified with its native Shine-Dalgarno sequence upstream. The start codon of the β-galactosidase gene partially overlapped with the stop codon of vector origin open reading frame. Then, the recombinant plasmids were transformed into Escherichia coli DH5α and Lactococcus lactis subsp, lactis MG1363 and confirmed by determining β-galactosidase activities. Results The non-fusion expression plasmids showed a significantly higher β-galactosidase activity in transformed strains than the fusion expression plasmids. The highest enzyme activity was observed in Lactococcus lactis transformed with the non-fusion expression plasmids which were inserted into the β-galactosidase gene from Lactobacillus bulgaricus wch9901. The β-galactosidase activity was 2.75 times as high as that of the native counterpart. In addition, β-galactosidase expressed by recombinant plasmids in Lactococcus lactis could be secreted into the culture medium. The highest secretion rate （27.1%） was observed when the culture medium contained 20 g/L of lactose. Conclusion Different properties of the native bacteria may have some effects on the protein expression of recombinant plasmids. Non-fusion expression shows a higher enzyme activity in host bacteria. There may be a host-related weak secretion signal peptide gene within the structure gene of Lb. bulgaricus β-galactosidase, and its translation product may introduce the enzyme secretion out of cells in special hosts.
基金supported by the National Science Foundation of China (NO. 30800910)
文摘Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant plasmid pMG36e-usp-lacZ.This recombinant plasmid was transformed into both Escherichia coli DH5α and L.lactis MG1363.The enzyme activity,gene sequencing,SDS-PAGE and hereditary stability were assessed and studied.Results The lacZ gene inserted into plasmids pMG36e-usp-lacZ was 99.37% similar to the GenBank sequence,and SDS-PAGE revealed an evident idio-strap at 116 KDa between L.lactis MG1363/pMG36eusp-lacZ in both supernatant and cell samples.β-Galactosidase activity measured 0.225 U/mL in L.lactis pMG36e-usp-lacZ transformants,and its secretion rate was 10%.The plasmid pMG36e-usp-lacZ appeared more stable in MG1363.Conclusion The authors concluded that these new recombinant bacteria well expressed and secreted β-galactosidase,indicating that the β-galactosidase expression system was successfully constructed,and this might provide a new solution for management of lactose intolerance specifically and promote the use of gene-modified organisms as part of the food-grade plasmid in general.
基金Supported by the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), No.980198
文摘AIM： To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS： The C-terminal 19-ku fragments of MSP1 （MSP-119） of Plasmodium yoelii265-BY was expressed in L. lactis and the recombinant L. lact/s was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythroo/tic stage. The protective efficacy of recombinant L. lactiswas evaluated. RESULTS： The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8± 0.4% and 20.8±26.5%, respectively, and those of their control groups were 12.0±0.8% and 60.8±9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. CONCLUSION： The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.
文摘The autolysis and proteolysis are important features in the strains of L. lactis used in the manufacture of cheese. The autolytic and proteolytic activity of L. lactis has been linked with the development of flavor and texture in the cheese. On the other hand, there is a growing interest in new strains isolated from raw-milk cheeses and vegetables. These wild-strains have showed different features of industrial importance in comparison with those observed in commercial cultures. However, it still not clear if the autolytic and proteolytic properties of these wild-strains differ from the industrial strains. The objective of this work was to assess the autolytic and proteolytic activities of 21 strains of L. lactis isolated from diverse sources. The rates of autolysis and proteolysis observed in vitro were highly strain-dependent. The pH and the NaCl concentration in the media affected significantly the autolysis of L. lactis. The strains isolated from vegetable showed in general low and medium autolytic activity, whereas the strains isolated from raw-milk cheeses had medium to high autolytic activity. The strain with highest proteolytic activity was a strain isolated from corn leaves. Although still not clear how this strain acquired this pronounced characteristic.
基金Supported by Priority Academic Talent Team Cultivation Program of Shandong Colleges and Universities and Agricultural Industry Research System of Shandong Province(SDAIT-06-022-08)People’s Livelihood Science and Technology Program of Qingdao City(16-6-2-42-nsh)
文摘To evaluate the specific immune responses induced by recombinant Lactococcus lactis（L.lactis） which expresses porcine epidemic diarrhea virus（PEDV） S1 protein through oral administration,the spike gene fragment of PEDV was amplified from PEDV SDLY strain to construct p MG36 e-S1 recombinant plasmid.The recombinant plasmid was then electro-transferred into competent cells of L.lactis MG1363,to prepare the recombinant L.lactis expressing S1 protein of PEDV.The expression of target protein was identified by SDS-PAGE and Western-blot.New Zealand white rabbits were orally administered with the recombinant strain;the antibody titer in intestinal mucosa and serum was detected by neutralizing test;and the specific Ig G in serum was evaluated by indirect ELISA.The results showed that the recombinant L.lactis could effectively induce high level of Ig G in serum and high level of mucosal immune antibody.The recombinant L.lactis is qualified to be a potential oral vaccine because it could successfully stimulate both humoral and mucosal immune responses against PEDV.
基金The Seoul Research and Business Development Program, No. 10582Namyang Dairy Product Co. Ltd, which produced and provided the test and control yogurts for this study
文摘AIM: To investigate whether composite yogurt with acacia dietary fiber and Bifidobacterium lactis (B. lactis) has additive effects in irritable bowel syndrome (IBS). METHODS: A total of 130 patients were randomly allocated to consume, twice daily for 8 wk, either the composite yogurt or the control product. The composite yogurt contained acacia dietary fiber and high-dose B. lactis together with two classic yogurt starter cultures. Patients were evaluated using the visual analogscale via a structured questionnaire administered at baseline and after treatment. RESULTS: Improvements in bowel habit satisfaction and overall IBS symptoms from baseline were significantly higher in the test group than in the control group (27.16 vs 15.51, P = 0.010, 64.2 ± 17.0 vs 50.4 ± 20.5, P < 0.001; respectively). In constipation-predominant IBS, improvement in overall IBS symptoms was significantly higher in the test group than in the control group (72.4 ± 18.4 vs 50.0 ± 21.8, P < 0.001). In patients with diarrhea-predominant IBS, improvement in bowel habit satisfaction from baseline was significantly higher in the test group than in the control group (32.90 vs 7.81, P = 0.006). CONCLUSION: Our data suggest that composite yogurt enriched with acacia fiber and B. lactis has greater therapeutic effects in patients with IBS than standard yogurt.
