Application Of Bacterial Inoculants Research Articles

A Systematic Review on the Application of Bacterial Inoculants and Microbial Consortia During Green Waste Composting

A Systematic Review on the Application of Bacterial Inoculants and Microbial Consortia During Green Waste Composting

Testing Combined Effect of Amendments and Inoculation with Bacteria for Improving Phytostabilisation of Smelter Waste Extremely Contaminated with Trace Elements

Smelter waste deposits pose environmental and health threats and require remediation actions. Phytostabilisation techniques, based on soil amendments, help to establish plant cover and limit the secondary emission of potentially toxic trace elements. However, methods to optimize their effectiveness are needed. The application of bacterial inoculants in combination with soil amendments in the remediation of soils and wastes contaminated with metals still has not been extensively tested. Therefore, the aim of this study was to determine the effectiveness of indigenous (Streptomyces sp., Pseudomonas sp.) and foreign (Streptomyces costaricanus) strains of bacteria in supporting grass growth on extremely contaminated waste slag. They were applied alone and in combination with compost mixed with phosphate fertilizer or iron oxide. The tested strains improved plant growth and increased plant availability of phosphorus. The interaction of the soil amendments and some bacterial strains also stimulated a decrease in the extractability of metals, likely through the phosphate-induced precipitation of lead. Our data show that the effectiveness of soil amendments in the phytostabilisation of heavily polluted smelter deposits can be enhanced by plant growth-promoting bacteria (PGPB).

A novel encapsulation of Streptomyces fulvissimus Uts22 by spray drying and its biocontrol efficiency against Gaeumannomyces graminis, the causal agent of take-all disease in wheat.

Wheat is a valuable food source that is exposed to many diseases that reduce its quantity and quality. One of the most important diseases affecting wheat is take-all, caused by Gaeumannomyces graminis var. tritici. The application of bacterial inoculants into the soil can increase plant nutrient absorption and enhance the efficiency of probiotic bacteria. For increased beneficial bacteria efficiency, the encapsulation technique has been used in agriculture. The results of Fourier transform infrared (FTIR) and X-ray diffraction analysis (XRD) indicated that the prepared formulation is a mixture of gellan and chitosan. Using SEM, the spherical structure of the microcapsules was confirmed. It was observed that the increase in bacterial release was gradual, and the highest amount of bacteria was released (109 CFU mL-1 ) on the 50th day. Greenhouse experiments showed that plants treated with S. fulvissimus Uts22 microcapsules had the highest efficiency with 90% disease control. Moreover, the highest fresh and dry weights of roots and shoots were observed in this treatment. In this study, a new type of formulation aiming at controlling wheat take-all disease was developed through bacterial and nanoparticles loaded chitosan- gellan gum microcapsules with spray drying method. This formulation has many advantages, such as a large surface area and high internal porosity and increased water-holding capacity, while it also provides a proper habitat for bacteria to increase colonization rates and offers protection of the soil. © 2021 Society of Chemical Industry.

Effects of lactobacillus plantarum inoculants on maize silage quality

In the winter time in Serbia, maize silage is the main ruminant feed. Therefore, managing maize silage is an important contributor to maintain the silage quality for livestock feed. In the study were evaluated the chemical composition, energetic and fermentation characteristics in whole-crop maize silage inoculated with different bacterial inoculants under field conditions in the commercial dairy farm, during the 2015. Three treatments were tested: negative control (untreated silage), a positive control (competitor inoculant) and Silko treatment (contains a mixture of 4 strains of Lactobacillus plantarum (LP1, LP2, LP3 and LP4). Maize is ensiled in the milk-wax grain maturity. After 90 days of ensiling, the maize silages were analyzed. The application of bacterial inoculants improved the chemical composition and energetic characteristics of silage. The inoculant Silko was more effective at improving the fermentation characteristics than competitor inoculant. Ash, cellulose, soluble N/TN, NH3-N/TN, ADF, NDF, acetic acid and pH were significantly lower in Silko treatment than positive control. There were no differences in crude fat, crude protein, ME, NEL, lactic acid and butyric acid between the treated silages. Generally, the new product bacterial inoculant Silko proved in field trials its ability to support the ensiling process in maize. The main action of the bacterial inoculant Silko is performed in two ways: the reduced degradation of protein in silage and the improvement of the aerobic stability due to the lower pH, higher content of acetic acid than negative control.

Different aspects of Lactobacillus inoculants on the improvement of quality and safety of alfalfa silage

There is a significant range of bacterial inoculants for forage ensiling, but there is still a need for formulations to improve the safety of feed. The objective of the study was to evaluate the usefulness of three lactobacilli strains in alfalfa (Medicago sativa L.) The following bacterial inoculants were used: Lactocacillus plantarum K KKP 593p (LPK), L. plantarum C KKP 788p (LPC), L. buchneri KKP 907p (LB), and mix of all three strains (LPK+LPC+LB). The application of bacterial inoculants in alfalfa ensiling resulted in a reduction of the total number of molds, Clostridium perfringens and Listeria sp. (up to 5, 7, and 5 times respectively for LB inoculant in comparison to untreated silage). Total inhibition of Salmonella sp. and Escherichia coli growth was achieved in silages treated with all inoculants except for LPC. Aerobic stability in the control silage was the lowest (77 h) and doubled under the influence of bacterial inoculants. The most stable according to aerobic stability was silage treated with LB inoculant (175 h), where the highest concentrations of acetic acid (4.8 g kg-1), propionic acid (0.7 g kg-1) and 1,2-propanediol (526 mg kg-1) were reported. The study discussed that it is important to evaluate not only the effect of bacterial inoculants on physicochemical and microbiological silage properties, as the presence and expression of antibiotic resistance genes in lactic acid bacteria have been reported. The results of antimicrobial susceptibility testing of the strains showed that almost all minimum inhibitory concentrations values for eight antibiotics were equal to or below the corresponding breakpoints proposed by the European Food Safety Authority, Additives and Products or Substances used in Animal Feed Panel.

Effects of microbial additives on chemical composition and fermentation characteristics of barley silage.

This study examined the effects of bacterial inoculants on chemical composition and fermentation indices of barley silage. Barley forage (Youngyang) was harvested at 24% dry matter (DM) and wilted to 47.9% DM. The wilted barley forage was chopped to 3–5 cm length and applied with no inoculant (CON), L. plantarum (1×1010 cfu/g, LP) or Effective Microorganisms (0.5×109 cfu/g, EM). Then the forages were ensiled in four replications for each treatment in 20 L mini silos and stored for 100 days. The contents of crude protein and ether extract were higher in CON silage ensiled for 100-d, while the contents of DM and crude ash were higher in EM silage (p<0.05). The contents of ADF, NDF and hemicellulose as well as the in vitro DM digestibility were not affected by microbial inoculation (p>0.05). The pH, ammonia-N concentration and lactate to acetate ratio were higher (p<0.05) in CON silage, while lactate concentrations were higher (p<0.05) in CON and LP silage. Acetate concentration and lactic acid bacteria was increased (p<0.05) by both inoculants (LP and EM), but propionate concentration and yeast was increased (p<0.05) by EM and LP, respectively. These results indicated that the fermentation quality of barley silage was improved by the application of bacterial inoculants.