Mangrove’s rhizospheric engineering with bacterial inoculation improve degradation of diesel contamination

Soil contamination by different hydrocarbons has rapidly expanded worldwide, surpassing the self-purification capacity of soils and increasing the number of contaminated sites. Although much effort has been devoted to study the effects of diesel contamination on the geotechnical properties of soil, there is still limited available information about it. Moreover, there is no available information about the maximum diesel retention that soil can have and its effect on the geotechnical behavior of the soil. Thus, in this paper, we determined the maximum diesel retention by an unsaturated clayey soil and evaluated the impact of diesel contamination on its geotechnical properties. The results showed that the soil could only retain 12.6% of the added diesel and the excess was expulsed. At such a diesel concentration, the saturation rate of the soil was lower than 80%. Diesel contamination increased the plasticity and the internal friction angle of the soil, while its cohesion was considerably decreased. It should be noted that the matric suction of contaminated soil was lower than the one obtained for natural soil. However, its osmotic suction was considerably higher. This indicates that osmotic suction must be considered to evaluate the shear strength of contaminated soils.

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Effect of Fenton pretreatment and bacterial inoculation on cellulose-degrading genes and fungal communities during rice straw composting

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.151376 ◽

2021 ◽

pp. 151376

Author(s):

Di Wu ◽

Fengting Qu ◽

Dan Li ◽

Yue Zhao ◽

Xiang Li ◽

...

Keyword(s):

Rice Straw ◽

Fungal Communities ◽

Bacterial Inoculation

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Influence of Inoculation Method, Spot Inoculation Site, and Inoculation Size on the Efficacy of Acidic Electrolyzed Water against Pathogens on Lettuce

Journal of Food Protection ◽

10.4315/0362-028x-66.11.2010 ◽

2003 ◽

Vol 66 (11) ◽

pp. 2010-2016 ◽

Cited By ~ 45

Author(s):

SHIGENOBU KOSEKI ◽

KYOICHIRO YOSHIDA ◽

YOSHINORI KAMITANI ◽

KAZUHIKO ITOH

Keyword(s):

Population Size ◽

Room Temperature ◽

Escherichia Coli O157 ◽

Bacterial Inoculation ◽

Pathogen Population ◽

Salmonella Spp ◽

Electrolyzed Water ◽

Inoculation Methods ◽

E Coli ◽

Inoculation Site

The influence of bacterial inoculation methods on the efficacy of sanitizers against pathogens was examined. Dip and spot inoculation methods were employed in this study to evaluate the effectiveness of acidic electrolyzed water (AcEW) and chlorinated water (200 ppm free available chlorine) against Escherichia coli O157:H7 and Salmonella spp. Ten pieces of lettuce leaf (5 by 5 cm) were inoculated by each method then immersed in 1.5 liters of AcEW, chlorinated water, or sterile distilled water for 1 min with agitation (150 rpm) at room temperature. The outer (abaxial) and inner (adaxial) surfaces of the lettuce leaf were distinguished in the spot inoculation. Initial inoculated pathogen population was in the range 7.3 to 7.8 log CFU/g. Treatment with AcEW and chlorinated water resulted in a 1 log CFU/g or less reduction of E. coli O157:H7 and Salmonella populations inoculated with the dip method. Spot inoculation of the inner surface of the lettuce leaf with AcEW and chlorinated water reduced the number of E. coli O157:H7 and Salmonella by approximately 2.7 and 2.5 log CFU/g, respectively. Spot inoculation of the outer surface of the lettuce leaf with both sanitizers resulted in approximately 4.6 and 4.4 log CFU/g reductions of E. coli O157:H7 and Salmonella, respectively. The influence of inoculation population size was also examined. Each sanitizer could not completely eliminate the pathogens when E. coli O157:H7 and Salmonella cells inoculated on the lettuce were of low population size (103 to 104 CFU/g), regardless of the inoculation technique.

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The Effect of Bacillus licheniformis MH48 on Control of Foliar Fungal Diseases and Growth Promotion of Camellia oleifera Seedlings in the Coastal Reclaimed Land of Korea

Pathogens ◽

10.3390/pathogens8010006 ◽

2019 ◽

Vol 8 (1) ◽

pp. 6 ◽

Cited By ~ 4

Author(s):

Sang-Jae Won ◽

Jun-Hyeok Kwon ◽

Dong-Hyun Kim ◽

Young-Sang Ahn

Keyword(s):

Total Nitrogen ◽

Bacillus Licheniformis ◽

Growth Promotion ◽

Dry Weight ◽

Fungal Diseases ◽

Camellia Oleifera ◽

Bacterial Inoculation ◽

Lytic Enzymes ◽

Nitrogen And Phosphorus ◽

Reclaimed Land

This study investigated the control of foliar fungal diseases and growth promotion of Camellia oleifera seedlings in coastal reclaimed land through the use of Bacillus licheniformis MH48. B. licheniformis MH48 can produce lytic enzymes chitinase and β-1,3-glucanase that can inhibit foliar pathogens by 37.4 to 50.5%. Nevertheless, foliar diseases appeared in the seedlings with bacterial inoculation, and their survival rate decreased because they were unable to withstand salt stress. However, B. licheniformis MH48 significantly increased the total nitrogen and phosphorus contents in the soils through fixing atmospheric nitrogen and solubilizing phosphorus. The growth of seedlings with bacterial inoculation increased, particularly in root dry weight, by 7.42 g plant−1, which was 1.7-fold greater than that of the control. B. licheniformis MH48 produces the phytohormone auxin, which potentially stimulates seedling root growth. C. oleifera seedlings significantly increased in total nitrogen content to 317.57 mg plant−1 and total phosphorus content to 46.86 mg plant−1. Our results revealed the effectiveness of B. licheniformis MH48 not only in the control of foliar fungal diseases but also in the growth promotion of C. oleifera seedlings in coastal lands.

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Evidence of nitrogen fixation in lodgepole pine inoculated with diazotrophic Paenibacillus polymyxa

Botany ◽

10.1139/b2012-044 ◽

2012 ◽

Vol 90 (9) ◽

pp. 891-896 ◽

Cited By ~ 36

Author(s):

Amandeep Bal ◽

Christopher P. Chanway

Keyword(s):

Seedling Growth ◽

Pinus Contorta ◽

Lodgepole Pine ◽

Growth Period ◽

Paenibacillus Polymyxa ◽

N Fixation ◽

Bacterial Strains ◽

Bacterial Inoculation ◽

Foliar N ◽

Negative Effect

Diazotrophic bacteria previously isolated from internal tissues of naturally regenerating lodgepole pine ( Pinus contorta var. latifolia (Dougl.) Engelm.) seedlings were tested for their ability to colonize and fix nitrogen (N) in pine germinants in two experiments. Surface sterilized pine seed was sown in glass tubes containing an autoclaved sand – montmorillonite clay mixture that contained a N-limited nutrient solution labeled with 15N as 0.35 mmol·L–1 Ca(15NO3)2 (5% 15N label). Pine seed was inoculated with one of three of the following bacterial strains: Paenibacillus polymyxa P2b-2R, P. polymyxa P18b-2R, or Dyadobacter fermentans P19a-2R, and seedlings grew for either 27 or 35 weeks. At the end of each plant growth period, P. polymyxa strain P2b-2R was detected in the pine rhizosphere but not inside plant tissues. Pine foliar N concentrations were not affected by bacterial inoculation but significant foliar 15N dilution was observed in seedlings treated with strain P2b-2R (30% and 66%, P < 0.05, in the first and second experiments, respectively). This strain also reduced seedling biomass in both experiments but effects were significant only in the second experiment (36%, P < 0.05). Notwithstanding the negative effect of bacterial inoculation on seedling growth, pine seedlings inoculated with strain P2b-2R derived 30% and 66%, respectively, of their foliar N from bacterial N fixation in two seedling growth experiments. These results demonstrate the possibility that some endophytic diazotrophs facilitate pine seedling growth in N-poor soils.

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THE REDUCTION OF Cr(VI) IN SOIL BY Microbacterium sp. STRAIN SpR3 IN VERMICOMPOST CARRIER

Jurnal Bioteknologi & Biosains Indonesia (JBBI) ◽

10.29122/jbbi.v8i1.4160 ◽

2021 ◽

Vol 8 (1) ◽

pp. 33-41

Author(s):

Theodorus Olwyn Innation ◽

Vincentia Irene Meitiniarti ◽

Desti Christian Cahyaningrum

Keyword(s):

Hexavalent Chromium ◽

Bacterial Inoculation ◽

Industrial Activities ◽

Number Of Bacteria ◽

Bioremediation Agent

Reduksi Cr(VI) pada Tanah Menggunakan Microbacterium sp. Strain SpR3 dengan Bahan Pembawa Vermikompos Kromium hexavalen [Cr(VI)] adalah polutan yang berasal dari kegiatan industri. Microbacterium sp. strain SpR3 dapat digunakan sebagai agen bioremediasi Cr(VI). Kemampuan agen biologi untuk mereduksi Cr(VI) umumnya meningkat bila diinokulasi dalam media pembawa. Tujuan penelitian ini adalah untuk menganalisis kemampuan Microbacterium sp. strain SpR3 dalam mengurangi Cr(VI) serta membandingkannya dengan kondisi ketika diinokulasi dalam media pembawa vermikompos. Pengamatan dilakukan selama tujuh hari pada tiga perlakuan yang berbeda, yakni Microbacterium sp. strain SpR3 dengan dan tanpa media pembawa vermikompos yang diinokulasi pada tanah steril yang mengandung 50 ppm Cr(VI), dan tanah steril tanpa inokulasi bakteri yang mengandung 50 ppm Cr(VI). Variabel yang diamati adalah jumlah bakteri, konsentrasi, dan kecepatan reduksi Cr(VI) oleh bakteri tersebut di dalam tanah pada T0 (hari ke-0) dan T7 (hari ke-7). Hasil penelitian ini menyimpulkan bahwa vermikompos bisa digunakan sebagai media pembawa Microbacterium sp. strain SpR3 karena dapat meningkatkan jumlah bakteri sampai 2 × 1010 CFU g-1 di dalam tanah dan dapat mengurangi Cr(VI) dengan kecepatan 0,095 mg L-1 jam-1. Hexavalent chromium [Cr(VI)] is a pollutant originated from industrial activities. Microbacterium sp. strain SpR3 can be used as Cr(VI) bioremediation agent. The ability of bioagent to reduce Cr(VI) usually improves when inoculated in a carrier. This research aimed to assess the ability of Microbacterium sp. strain SpR3 to reduce Cr(VI) in soil and compare its ability when inoculated in vermicompost carrier. Observations were carried out for seven days on three different treatments, namely Microbacterium sp. strain SpR3 with and without vermicompost inoculated in sterile soils containing 50 ppm Cr(VI), and sterile soils containing 50 ppm Cr(VI) without bacterial inoculation. The observed variables were the number of bacteria, the concentration of Cr(VI) and the rate of Cr(VI) reduction by these bacteria in the soil at T0 (day 0) and T7 (day 7). It was concluded that vermicompost could be used as a carrier of Microbacterium sp. strain SpR3 as it could increase the number of the bacteria to 2 × 1010 CFU g-1 in soil and could reduce Cr(VI) at the rate of 0.095 mg L-1 h-1.

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