Microbial Population Dynamics during Phytobioremediation of Hydrocarbon- Contaminated Swampy and Clay Soils

Year : 2026 | Volume : 13 | Issue : 01 | Page : 31 35
    By

    Uku Eruni Philip,

  • Uhegwu Promise Nkwachi,

  1. Lecturer, Department of Chemical Engineering, Federal University, Otuoke, Bayelsa State, Nigeria
  2. PhD Scholar, Department of Chemical/Petrochemical Engineering, Rivers State University, Port Harcourt, Rivers State, Nigeria

Abstract

Soil contamination by petroleum hydrocarbons remains a critical environmental challenge, particularly in wetland and clay-rich ecosystems where natural attenuation processes are often limited. This study investigates the response of total heterotrophic bacteria (THB) during the bioremediation of hydrocarbon-contaminated swampy and clay soils amended with Moringa oleifera biomass and elephant grass (Pennisetum purpureum). The objective was to evaluate microbial population dynamics under varying amendment dosages and to identify treatment conditions favorable for total petroleum hydrocarbon (TPH) degradation. Laboratory-scale bioremediation experiments were conducted over an 84-day period using amendment dosages ranging from 20 g to 100 g, alongside untreated control samples. Total heterotrophic bacterial counts were monitored at regular intervals using standard plate count techniques, while hydrocarbon-utilizing bacteria were isolated and identified. Results revealed that microbial populations increased significantly following contamination and amendment, with bacterial growth strongly influenced by amendment type, dosage, soil texture, and remediation duration. In all amended samples, THB counts increased progressively and reached peak values at the 56th day before declining, indicating substrate depletion and possible nutrient limitation. Maximum THB counts of 1.01 × 10⁷ cfu/ml and 1.12 × 10⁷ cfu/ml were recorded in swampy soil treated with 100 g of moringa and elephant grass, respectively. In contrast, control samples exhibited continuous but comparatively lower microbial growth throughout the study period. Predominant hydrocarbon-degrading bacteria identified included Pseudomonas, Bacillus, and Proteus species. The findings demonstrate that plant-based amendments significantly enhance microbial proliferation and support effective bioremediation of hydrocarbon-polluted soils. This study highlights the potential of locally available plant materials as sustainable biostimulation agents for petroleum-impacted environments.

Keywords: Bioremediation; Total heterotrophic bacteria; Hydrocarbon-contaminated soil; Moringa oleifera; Elephant grass

[This article belongs to Emerging Trends in Chemical Engineering ]

How to cite this article:
Uku Eruni Philip, Uhegwu Promise Nkwachi. Microbial Population Dynamics during Phytobioremediation of Hydrocarbon- Contaminated Swampy and Clay Soils. Emerging Trends in Chemical Engineering. 2026; 13(01):31-35.
How to cite this URL:
Uku Eruni Philip, Uhegwu Promise Nkwachi. Microbial Population Dynamics during Phytobioremediation of Hydrocarbon- Contaminated Swampy and Clay Soils. Emerging Trends in Chemical Engineering. 2026; 13(01):31-35. Available from: https://journals.stmjournals.com/etce/article=2026/view=237760


References

  1. Rajendran S, Ramesh P, Srirangarayan RS. Biostimulation of Petroleum Contaminated Soil Using Organic Amendments. InBioremediation of Petroleum Contaminated Soil and Sediment 2026 Jan 2 (pp. 191-217). Cham: Springer Nature Switzerland.
  2. Lee YY, Cho KS, Yun J. Phytoremediaton strategies for Co-contaminated soils: overcoming challenges, enhancing efficiency, and exploring future advancements and innovations. Processes. 2025 Jan 6;13(1):132.
  3. Ogidi OI, Akpan UM. Microbial and Phytoremediation of Crude Oil- Contaminated Soil. InEco-Restoration of Polluted Environment 2024 (pp. 110-128). CRC Press.
  4. Ogbonna DN, Ekweozor IK, Nrior RR, Ezinwo FE. Evaluation of Organic Nutrient Supplements and Bioaugmenting Microorganisms on Crude Oil Polluted Soils. Current Journal of Applied Science and Technology. 2019 Nov 30;38(6):1-9.
  5. Onyiba PO, Mbah TN, Ikoro AI, Okoh T, Achebe U, Ajisola JK. Suitability assessment of orange-fleshed sweet potato for sustainable nutrition security. Centennial. 2023 Nov;568.
  6. Dayananda NR, Wijesinghe J, Botheju SM, Perera WP, Liyanage JA. Ocean Warming, Acidification, Plastic Pollution, and Water Quality Deterioration: A Multifaceted Crisis Unveiled. Coastal and Marine Pollution: Source to Sink, Mitigation and Management. 2025 Apr 24:111-38.
  7. Girma G. Microbial bioremediation of some heavy metals in soils: an updated review. Egyptian Academic Journal of Biological Sciences, G. Microbiology. 2015 Dec 1;7(1):29-45.
  8. Pino-Herrera DO, Pechaud Y, Huguenot D, Esposito G, van Hullebusch ED, Oturan MA. Removal mechanisms in aerobic slurry bioreactors for remediation of soils and sediments polluted with hydrophobic organic compounds: An overview. Journal of hazardous materials. 2017 Oct 5;339:427-49.
  9. Ukpaka CP, Nkakini SO. Crude oil remediation using matlab integrated agricultural best management practice to improved soil nutrients. Petroleum & Petrochemical Engineering Journal. 2017;1(1):101-6.
  10. Ukpaka C. Development of model for bioremediation of crude oil using moringa extract. Chem. Int. 2016;2(9).
  11. Torres-Farradá G, Manzano AM, Ramos-Leal M, Domínguez O, Sánchez MI, Vangronsveld J, Guerra G. Biodegradation and detoxification of dyes and industrial effluents by Ganoderma weberianum B-18 immobilized in a lab-scale packed-bed bioreactor. Bioremediation Journal. 2018 Apr 3;22(1-2):20-7.
Regular Issue Subscription Original Research
Volume 13
Issue 01
Received 30/01/2026
Accepted 02/02/2026
Published 27/02/2026
Publication Time 28 Days
139

Login


My IP

PlumX Metrics