Biofilm-overproducing Bacillus amyloliquefaciens P29ΔsinR decreases Pb availability and uptake in lettuce in Pb-polluted soil

2022 ◽  
Vol 302 ◽  
pp. 114016
Author(s):  
ZhiHui Xiong ◽  
JinWei Zheng ◽  
HaiRong Sun ◽  
JingWen Hu ◽  
XiaFang Sheng ◽  
...  
Author(s):  
David N. Ogbonna ◽  
Renner R. Nrior ◽  
Festus E. Ezinwo

Aim: To assess the Bioremediation efficiency of Bacillus amyloliquefaciens and Pseudomonas aeruginosa strain CL 9 with nutrient amendment using bio-stimulating agents such as Fish waste and Goat manure on crude oil polluted soils in Rivers State, Nigeria. Study Design: The study employs experimental design, statistical analysis of the data and interpretation. Place and Duration of Study: A portion of Rivers State University demonstration farmland in Nkpolu-Oroworukwo, Mile 3 Diobu area of Port Harcourt, Rivers State was used for this study. The piece of land is situated at Longitude 4°48’18.50’’N and Latitude 6o58’39.12’’E measuring 5.4864 m x 5.1816 m with a total area of 28.4283 m2. Bioremediation monitoring lasted for 56 days, analysis carried out weekly (per 7 days interval). Methodology: Seven (7) experimental plots were employed using a Randomized Block Design each having dimensions of 100 x 50 x 20 cm (Length x Breadth x Height) were formed and mapped out on agricultural soil and left fallow for 6 days before contamination on the seventh day; after which it was allowed for 21 days for proper contamination and exposure to natural environmental factors to mimic crude oil spill site. Thereafter bio stimulating agents usually referred to as nutrient amendment organics in this study (fish waste and goat manure) and bio-augmenting microorganisms were applied. Soil profile before and after contamination was assayed while parameters like Nitrate, Sulphate, Phosphate, Total Organic Carbon (TOC) and Total Petroleum Hydrocarbon (TPH), were monitored throughout the experimental period. Microbial analyses such as Total Heterotrophic Bacteria (THB), Total Heterotrophic Fungi (THF), Hydrocarbon Utilizing Bacteria (HUB) and Hydrocarbon Utilizing Fungi (HUF) were recorded. Bioremediation efficiency was estimated from percentage (%) reduction of Total Petroleum Hydrocarbon (TPH) from day 1 to the residual hydrocarbon at day 56 of bio augmented/ biostimulation plots with the control. Results: Results revealed amount of remediated hydrocarbon and % Bioremediation efficiency at 56 days in the different treatment plots (initial TPH contamination value of  9296.83  mg/kg) in a decreasing order as follows: PS+Bac+Pse+GF+FW (8032.825 mg/kg; 86.40%) >PS+GF+FW (6867.825 mg/kg; 73.87%) >PS+Bac+Pse (6587.825mg/kg; 70.86%) >PS+FW (6441.825mg/kg; 69.29%) >PS+GF (5909.825 mg/kg; 63.57%) >CTRL 2 (Polluted soil without amendment) (3604.825mg/kg; 38.78%). Microbiological results showed increased colonial values with increase time exposure. The results observed on day 56 indicate that Polluted soil + Bacillus + Pseudomonas (10.11 Log10 CFU/g) > Polluted soil but un-amended soil (8.76 Log10 CFU/g) > unpolluted soil (8.68 Log10 CFU/g). Comparatively, Polluted soil +Bacillus + Pseudomonas expressed higher heterotrophic bacteria of 9.77 and 9.67 Log10 CFU/g while fungal counts recorded 6.04 and 6.82 Log10 CFU/g. Conclusion: Study showed that bioremediation of crude oil-polluted soils with bacteria singly is less effective but a combination with other organic nutrients is a better palliative measure. Therefore, amendment with organic nutrients like Goat manure and Fish wastes is recommended for crude oil polluted soils due to its high nutrient content as substrates for biostimulation of indigenous and augmenting biodegrading microbes. This process could be a source of enhanced natural attenuation of oil-contaminated environments in Nigeria.


Author(s):  
Nguyễn Thị Bích Đào ◽  
Trần Quang Khánh Vân ◽  
Nguyễn Văn Khanh ◽  
Nguyễn Quang Linh

Khi tình hình bệnh hội chứng tôm chết sớm (EMS) đã gây thiệt hại vô cùng to lớn đối với Nuôi trồng thủy sản thì các giải pháp được đề nghị và áp dụng nhằm hạn chế dịch bệnh. Trong đó, việc tìm hiểu và đưa vi khuẩn có lợi để cạnh tranh và ức chế loài vi khuẩn gây bệnh rất được quan tâm, được cho là giải pháp có nhiều triển vọng phù hợp với điều kiện môi trường, đảm bảo sức khỏe cho con người, cũng như hạn chế được dịch bệnh. Đặc biệt, đưa vi khuẩn Bacillus spp. qua đường tiêu hóa của tôm ngay từ khi mới thả đã hạn chế được mật độ vi khuẩn Vibrio. Nghiên cứu này đã phân lập được các chủng Bacillus subtilis B1, Bacillus subtilis B2, Bacillus amyloliquefaciens B4và thử khả năng đối kháng với vi khuẩn Vibrio parahaemolyticus V1 ở các nồng độ 103, 104, 105, 106 CFU theo dõi ở các thời điểm 6h, 12h, 24h, 48h và 72h. Kết quả cho thấy cả ba chủng vi khuẩn Bacillus trên phân lập được đều có khả năng ức chế tốt vi khuẩn Vibrio parahaemolyticus V1, trong đó vi khuẩn Bacillus amyloliquefaciens B4 làtốt nhất với đường kính vòng kháng khuẩn 52,67 ± 4,31mm ở thời điểm 48h; hai chủng Bacillus subtilis B1, Bacillus subtilis B2 lầnlượt là  49,67 ± 3,15 mm, 44,07 ± 5,19 mm, với mức sai số có ý nghĩa thống kê p < 0,05.


2019 ◽  
Vol 18 (6) ◽  
pp. 1297-1309
Author(s):  
Antonis A. Zorpas ◽  
Maria K. Doula ◽  
Vassilis J. Inglezakis ◽  
Jose Pedreno Navvaro ◽  
Dimitrios J. Bilalis

2018 ◽  
Vol 69 (7) ◽  
pp. 1695-1698
Author(s):  
Marin Rusanescu ◽  
Carmen Otilia Rusanescu ◽  
Gheorghe Voicu ◽  
Mihaela Begea

A calcium bentonite from Orasu Nou deposit (Satu Mare Romania) was used as raw material. We have conducted laboratory experiments to determine the influence of bentonite on the degree of heavy metal retention. It has been observed that the rate of retention increases as the heavy metal concentration decreases. Experimental studies have been carried out on metal retention ( Zn) in bentonite. In this paper, we realized laboratory experiments for determining the influence of metal (Zn) on the growth and development of two types of plants (Pelargonium domesticum and Kalanchoe) and the effect of bentonite on the absorption of pollutants. These flowers were planted in unpolluted soil, in heavy metal polluted soil and in heavy metal polluted soil to which bentonite was added to observe the positive effect of bentonite. It has been noticed that the flowers planted in unpolluted soil and polluted with heavy metals to which bentonite has been added, the flowers have flourished, the leaves are still green and the plants whose soils have been polluted with heavy metals began to dry after 6 days, three weeks have yellowish leaves and flowers have dried. Experiments have demonstrated the essential role of bentonite for the removal of heavy metals polluted soil.


2020 ◽  
Vol 51 (6) ◽  
pp. 528-540
Author(s):  
I. V. Lyanguzova ◽  
M. S. Bondarenko ◽  
A. I. Belyaeva ◽  
M. N. Kataeva ◽  
V. Sh. Barkan ◽  
...  

LWT ◽  
2021 ◽  
pp. 111812
Author(s):  
Yu Lu ◽  
Xiangjin Cheng ◽  
Huanhuan Deng ◽  
Shouwen Chen ◽  
Zhixia Ji

Sign in / Sign up

Export Citation Format

Share Document