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1.
Curr Microbiol ; 77(3): 443-451, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31894376

RESUMO

Fengycin antibiotic displays a strong antifungal activity and inhibits the growth of a wide range of plant pathogens especially filamentous fungi. The main objective of the present study is to characterize fengycin variants produced by B. amyloliquefaciens strain (ET). LC-MS analysis of fengycin extracts has shown several molecular ion peaks corresponding to conventional fengycin homologues (MH + : m/z 1463.9; 1491.9; 1506) and some new ones (MH + : m/z 1433; 1447; 1461; and 1477). Further characterization of these precursor ions was carried out by LC-MS.MS analysis. Reporter fragment ions were observed (named A and B), they correspond to the cleavage of Orn2-Tyr3 (A), Glu1-Orn2 (B), and used for identifying fengycin variants. The reporter fragment couple ions [A/B] at [m/z 966.5/1080.5] and [m/z 994.4 /1108.5] represent fengycin A and B, respectively. The diagnostic ions at ([m/z 980/1094]) may correspond to fengycin C3, D, S or B2. Interestingly, unknown diagnostic product ions at [m/z 951/1065] and [m/z 979/1093] were detected for the first time in this study which prove that they correspond to new fengycin variants, named fengycin X and fengycin Y, respectively. The fengycin X results from a substitution of the glutamine amino acid (Q), at position 8 of the fengycin A peptide part, by an isoleucine (I) or a leucine (L) residue. This mutation should be the same in fengycin Y but compared to fengycin B.


Assuntos
Bacillus amyloliquefaciens/química , Bacillus amyloliquefaciens/genética , Lagos/microbiologia , Lipopeptídeos/química , Argélia , Substituição de Aminoácidos , Glutamina/genética , Isoleucina/genética , Leucina/genética , Mutação , Águas Salinas , Espectrometria de Massas em Tandem
2.
Indian J Microbiol ; 53(4): 447-52, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24426149

RESUMO

The phenotypic and genotypic diversity of the plant growth promoting Bacillus genus have been widely investigated in the rhizosphere of various agricultural crops. However, to our knowledge this is the first report on the Bacillus species isolated from the rhizosphere of Calendula officinalis. 15 % of the isolated bacteria were screened for their important antifungal activity against Fusarium oxysporum, Botrytis cinerea, Aspergillus niger, Cladosporium cucumerinium and Alternaria alternata. The bacteria identification based on 16S r-RNA and gyrase-A genes analysis, revealed strains closely related to Bacillus amyloliquefaciens, B. velezensis, B. subtilis sub sp spizezenii and Paenibacillus polymyxa species. The electro-spray mass spectrometry coupled to liquid chromatography (ESI-LC MS) analysis showed that most of the Bacillus isolates produced the three lipopeptides families. However, the P. polymyxa (18SRTS) didn't produce any type of lipopeptides. All the tested Bacillus isolates produced cellulase but the protease activity was observed only in the B. amyloliquefaciens species (9SRTS). The Salkowsky colorimetric test showed that the screened bacteria synthesized 6-52 µg/ml of indole 3 acetic acid. These bacteria produced siderophores with more than 10 mm wide orange zones on chromazurol S. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. amyloliquefaciens (9SRTS) had no significant (P > 0.05) effect on the pre-germination of the chickpea seeds. However, it increased the size of the chickpea plants and reduced the stem rot disease (P < 0.05).These results suggested that the Bacillus strains isolated in this work may be further used as bioinoculants to improve the production of C. officinalis and other crop systems.

3.
Animals (Basel) ; 11(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072915

RESUMO

The aim of this study was to investigate the effect of Tenebrio molitor meal (TM) and/or olive leaf powder (OL) supplementation to quail diet on animal performance, carcass yield and some blood parameters. One hundred and forty-four 1-day-old Japanese quails (body weight: 29.9 ± 0.46 g) were divided into four groups of 36 chicks, receiving four different diets, i.e., G1: Standard commercial (SCD); G2: SCD + 3% TM; G3: SCD + 3% OL; and G4: SCD + 3% TM + 2% OL. Feed and water were provided ad-libitum. The results showed that TM and OL inclusion promoted quail body weight at 5 weeks of age; p = 0.001. Feed conversion ratio (FCR) of G3 was significantly (p < 0.01) reduced compared to the other groups. Overall mortality was not different, at around 6.25%, between groups. Carcass [(71.5-74.3%)], gizzard [(2.5-2.7%)], heart [(1.1-1.2%)] and giblet [(6.8-6.9%)] yields were not influenced by the diet. No significant effect of the diet was observed for serum proteins, creatinine, urea and lipids. To conclude, the mixture of an incorporation of TM and OL in quail diet showed no adverse effects on growth performance, carcass constituent yields and serum constituents.

4.
Vet World ; 11(11): 1624-1629, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30587899

RESUMO

AIM: This study was aimed to evaluate the effects of Artemisia herba-alba (white wormwood) or olive leaf (Olea europaea) powder supplementation on growth performance, carcass yield, and serum biochemical parameters in broilers. MATERIALS AND METHODS: The study was conducted from April to May 2017 in Chemini region, Northern Algeria. A total of 60 1-day-old Ross 308 male chicks were divided into three groups consisted of 10 chicks, in each of two replications. The chicks in Group 1 were fed with a standard commercial diet (SCD); Group 2 received the same SCD with 2% supplementation of A. herba-alba powder; and Group 3 received the same SCD with 2% supplementation of O. europaea powder. Growth performance was measured with body weights every 2 weeks, daily feed intake, feed conversion ratio (FCR), and carcass yield at the end of 42 days of rearing. Blood samples were collected to analyze serum glucose, cholesterol, triglycerides, urea, and total protein levels. RESULTS: Results showed that, at 42 days of rearing, supplementation of O. europaea and A. herba-alba significantly increased (p<0.001) mean body weight (2230.10±26.38 g and 2117.42±26.38 g, respectively, vs. 2336.66±27.88 g in chicks of Group 1), but there was no significant difference (p≥0.05) among the three diets for FCR or percentage carcass yield. Among the serum biochemical parameters, glucose was significantly affected (p<0.01) by supplementation of olive leaf powder (1.90 g/L: Group 3), compared to the SCD (2.24 g/L: Group 1) or Artemisia powder (2.05 g/L: Group 2). Moreover, the supplementation of olive leaf powder in Group 3 broilers significantly affected (p<0.05) the serum cholesterol level (0.95 g/L), compared to the control diet (1.13 g/L). There was no significant difference (p≥0.05) for the other selected serum biochemical concentrations, namely triglycerides, urea, and total protein. CONCLUSION: The supplementation of Artemisia or olive leaf powder into the diet for broilers improved body weight by about 5% or 10%, respectively, at slaughter with moderate changes in blood biochemical parameters.

5.
Foods ; 6(8)2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28783118

RESUMO

This work aims to study the production of the biomass of S. cerevisiae on an optimized medium using date extract as the only carbon source in order to obtain a good yield of the biomass. The biomass production was carried out according to the central composite experimental design (CCD) as a response surface methodology using Minitab 16 software. Indeed, under optimal biomass production conditions, temperature (32.9 °C), pH (5.35) and the total reducing sugar extracted from dates (70.93 g/L), S. cerevisiae produced 40 g/L of their biomass in an Erlenmeyer after only 16 h of fermentation. The kinetic performance of the S. cerevisiae strain was investigated with three unstructured models i.e., Monod, Verhulst, and Tessier. The conformity of the experimental data fitted showed a good consistency with Monod and Tessier models with R² = 0.945 and 0.979, respectively. An excellent adequacy was noted in the case of the Verhulst model (R² = 0.981). The values of kinetic parameters (Ks, Xm, µm, p and q) calculated by the Excel software, confirmed that Monod and Verhulst were suitable models, in contrast, the Tessier model was inappropriately fitted with the experimental data due to the illogical value of Ks (-9.434). The profiles prediction of the biomass production with the Verhulst model, and that of the substrate consumption using Leudeking Piret model over time, demonstrated a good agreement between the simulation models and the experimental data.

6.
Appl Biochem Biotechnol ; 172(4): 1735-46, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24258791

RESUMO

This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were screened for their ability to inhibit growth of some phytopathogenic fungi on PDA and some roots exudates. The bacteria identification based on 16S r-RNA and gyrase-A gene sequence analysis showed that 71 % of the screened isolates belonged to Bacillus amyloliquefaciens and the rest were closely related to B. atrophaeus and B. mojavensis. Most of them had high spore yields (22 × 10(8)-27 × 10(8) spores/ml). They produced protease and cellulase cell wall-degrading enzymes while the chitinase activity was only observed in the B. atrophaeus (6SEL). A wide variety of lipopeptides homologous was detected by liquid chromatography-electrospray ionization-mass spectrometry analysis. Interestingly, some additional peaks with new masses were characterized, which may correspond to new fengycin classes. The isolates produced siderophores and indole-3- acetic acid phytohormone. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. atrophaeus (6SEL) significantly increased the size of the chickpea plants and reduced the stem rot disease (P < 0.05). These results suggest that these isolates may be used further as bio-inoculants to improve crop systems.


Assuntos
Bacillus/isolamento & purificação , Bacillus/fisiologia , Plantas/microbiologia , Argélia , Bacillus/genética , Cicer/crescimento & desenvolvimento , Cicer/microbiologia , RNA Ribossômico 16S/genética
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