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Article

The Effect of Exogenous N-Acylated-L-Homoserine Lactones on the Remediation of Chromium-Contaminated Soil by Shewanella purefaciens

by
Xusheng Zheng
,
Chenglong Zheng
,
Shufang Zhou
and
Dexun Zou
*
Department of Environmental Science & Engineering, Beijing University of Chemical Technology, Beijing 100029, China
*
Author to whom correspondence should be addressed.
Processes 2025, 13(9), 2931; https://doi.org/10.3390/pr13092931
Submission received: 31 July 2025 / Revised: 29 August 2025 / Accepted: 11 September 2025 / Published: 13 September 2025
(This article belongs to the Section Environmental and Green Processes)
Browse Figures
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Abstract

Microbial remediation of chromium-contaminated soil through extracellular electron transfer is an economical and environmentally friendly strategy. Exogenous quorum sensing (QS) signaling molecules could facilitate the process of electron transport. However, it remains unclear whether regulating QS could enhance the microbial remediation effect. In this study, exogenous N-acylated-L-homoserine lactones (AHLs) were added for the remediation of Cr(VI)-contaminated soil by S. putrefaciens. Various AHLs such as C8-HSL, C10-HSL, 3OC8-HSL, 3OC10-HSL and 3OC12-HSL were detected in the remediation, with the concentrations of 5.91 ng/L, 1.09 ng/L, 4.10 ng/L, 2.29 ng/L and 24.51 ng/L. The addition of C10-HSL and 3OC12-HSL significantly promoted the Cr(VI) reduction rates by 11.25% and 9.20%. There were also various AHLs in the Cr(VI) reduction by indigenous microorganisms. The AHLs species measured and their concentrations were C8-HSL (5.05 ng/L), C10-HSL (3.27 ng/L), C12-HSL (0.11 ng/L), 3OC8-HSL (0.11 ng/L), 3OC10-HSL (0.05 ng/L), and 3OC12-HSL (2.92 ng/L). Relative to the untreated control, supplementation with C8-HSL, C12-HSL, and 3OC12-HSL produced significant enhancements in the Cr(VI) reduction rates by 4.10%, 3.05%, and 2.24%, respectively (p < 0.05). Comparing the effects of AHL on the remediation by S. putrefaciens and indigenous microorganisms, it could be found that C10-HSL enhanced the remediation effect by increasing the reduction rates of S. putrefaciens, and 3OC12-HSL enhanced the remediation effect by increasing the reduction rates of indigenous microorganisms. This study introduces a distinctive pathway for the promotion of the microbial remediation effect and contributes to further understanding the communication mechanism between exogenous and indigenous microorganisms.

1. Introduction

Chromium (Cr) is extensively used in various industries, including electroplating, paint manufacture, tanning leather, and metallurgy [1]. In the natural environment, Cr exists primarily in two stable oxidation states: hexavalent chromium [Cr(VI)] and trivalent chromium [Cr(III)], which exhibit markedly different toxicities and mobilities [2]. Cr(VI) is highly toxic and mobile, capable of inducing intracellular oxidative stress and DNA damage. In contrast, Cr(III) is less hazardous to cells and demonstrates limited cellular permeability [3]. Consequently, a widely adopted strategy for mitigating Cr pollution involves the reduction of Cr(VI) to less harmful Cr(III) form [4,5]. Although physical and chemical remediation methods can be straightforward, efficient, and sometimes facilitate metal recovery, they often entail drawbacks such as high operational expense, significant energy consumption, and the potential to create secondary pollutants [6]. Biological remediation techniques, on the other hand, offer a more economical and environmentally sustainable alternative [7]. Among microbial reduction strategies, extracellular electron transfer provides a prominent advantage over intracellular enzymes reduction by preventing Cr(VI) from infiltrating cells and exerting toxic effects [8,9]. Dissimilatory iron-reducing bacteria (DIRB), an ancient group of microorganisms prevalent in diverse ecosystems, can facilitate Cr(VI) reduction via extracellular electron transfer [10,11,12]. Shewanella, a typical genus of DIRB, has been shown to reduce Cr(VI) in the presence of iron oxides. In this process, iron acts catalytically, as it undergoes cyclic redox transformations that enhance the reduction process [13,14,15].
Quorum sensing (QS) is a widespread communication modality among microorganisms, through which microorganisms secrete and detect signaling molecules to coordinate interspecies interactions and regulate group behaviors [16,17,18]. Signaling molecules, such as N-acylated-L-homoserine lactones (AHLs) and autoinducer-2 (AI-2), are synthesized and released into the environment [19,20]. When their concentrations reach a threshold, they bind to intracellular receptors and trigger gene expression, thereby modulating microbial activities [21,22].
AHLs, in particular, serve as crucial intraspecific signaling molecules and are regarded as a universal language in bacterial communication [23,24]. They have been shown to facilitate electron transfer and enhance the degradation of pollutants [25,26,27]. In bio-electrochemical systems (BESs), exogenous AHLs could promote extracellular electron transfer (EET) between cells and anodes by altering cell membrane permeability, regulating gene expression, or modulating the synthesis network of electron shuttles [28]. In addition, Edel et al. (2021) demonstrated that QS played a significant role in enhancing EET in Shewanella oneidensis by regulating the production of electron shuttles such as riboflavin [29]. Moreover, QS regulation influences biofilm formation, which is essential for direct electron transfer, and stimulates the synthesis of redox-active shuttles (e.g., quinones, flavins, and phenazines) that mediate indirect electron transfer [30].
Furthermore, QS plays an important role in heavy metal resistance mechanisms. At the intracellular level, QS modulates the activity of antioxidant enzymes, alleviating the oxidative stress caused by heavy metals and thereby improving bacterial survival under metal-induced stress conditions [31]. Additionally, QS controls the transcription of resistance genes involved in reducing cell membrane permeability, activating efflux pumps, and enhancing enzymatic detoxification processes [32,33].
During the microbial Cr(VI) reduction, AI-2-mediated QS could up-regulate the expression of chromate reductase and improve the reduction efficiency [34]. AHLs-mediated QS also played a crucial role in the regulation of the functional genes involved in electron transfer, Cr(VI) reduction, and Cr(VI) resistance [35]. However, these studies were conducted in water. The soil environment is more complicated and contains abundant indigenous microorganisms. There are few studies on the role of QS in the micro-remediation of Cr(VI)-contaminated soils. It remains unclear whether QS is involved in the remediation of Cr(VI)-contaminated soil by iron-reducing bacteria, and whether the micro-remediation effect could be enhanced by regulating QS. Therefore, the effect of exogenous signaling molecules on the microbial remediation of Cr(VI)-contaminated soils was investigated. To be specific, the main objectives of this paper were (1) to determine the species and concentrations of AHLs in Cr(VI) remediation; (2) to explore the influence of AHLs on the remediation effect; and (3) to analyze the role of AHLs played in the remediation.

2. Materials and Methods

2.1. Experimental Materials and Microbial Preparation

Shewanella putrefaciens CN32 was selected as the model microorganism for investigating microbial Cr(VI) reduction. The strain was obtained from the China Center for Type Culture Collection (CCTCC) and cultivated aerobically in LB medium at 30 °C with shaking at 180 rpm. Cells were harvested during the exponential growth phase by centrifugation (3500 RCF, 10 min), followed by three washes using anoxic HEPES buffer (30 mM, pH 7.0). The cell pellets were subsequently resuspended in anoxic HEPES buffer within an anaerobic chamber for subsequent experiments.
Ferrihydrite was synthesized according to the method described by Ryden [36]. Briefly, 0.4 M Fe(NO3)3·9H2O was titrated with 1 M NaOH to reach pH 7 under continuous stirring. The resulting precipitate was washed repeatedly with deionized water and finally lyophilized.
The N-acylated-L-homoserine lactones (AHLs) employed—C8-HSL, C10-HSL, C12-HSL, 3OC8-HSL, 3OC10-HSL, and 3OC12-HSL—were procured from Macklin (Shanghai, China). The Cr(VI) reagent, potassium dichromate (K2Cr2O7), was acquired from Sinopharm Chemical Reagent Co. (Shanghai, China). All chemicals were of reagent-grade or higher.

2.2. Soil Samples

Soils were collected at the campus of Beijing University of Chemical Technology (BUCT). After coarse debris (stones, roots, and branches) was removed, samples were obtained from the 0–20 cm horizon using sterilized tools. Each sample was promptly labeled, placed in a sterile container, and transported at 4 °C to the laboratory.
Subsequently, potassium dichromate solution was added to the soils to make the final Cr(VI) concentration reach approximately 1500 mg/kg. Then the soil samples were stirred and placed in a cool ventilated place to undergo natural aging for 30 days. To sustain moisture, deionized water was added at regular intervals. For physicochemical analyses, aliquots were air-dried and passed through a 100-mesh sieve. The comprehensive soil properties are presented in Table 1.

2.3. Identification of AHLs in the Microbial Reduction of Cr(VI)

The species and concentrations of AHLs were investigated in the process of microbial Cr(VI) reduction in water and soil by S. putrefaciens. Glass media bottles were used for batch tests. In water-phase microbial Cr(VI) reduction experiments, reactors held 100 mL deoxygenated 30 mM HEPES buffer (pH 7.0) with the following additions as required: Cr(VI) at 30 mg/L, ferrihydrite at 2.0 g/L, and 1 mL of a bacterial suspension adjusted to OD600 = 2.0. Filter-sterilized sodium lactate was added as an excess electron donor at a final concentration of 10 mM. In the experiment of microbial Cr(VI) reduction in soil, reactors contained Cr(VI)-contaminated soil (50 g), ferrihydrite (0.25 g), sodium lactate (4 g), and 5 mL bacterial suspension (OD600 = 2.0). All reactors were sealed with Parafilm and incubated at 30 °C, 150 rpm. All experiments were run in triplicate. During incubation, samples were periodically collected inside an anaerobic glove box for AHLs concentration detection.

2.4. The Influence of AHLs on the Microbial Reduction of Cr(VI)

Glass media bottles were used for batch tests to investigate the effect of AHLs on the microbial reduction of Cr(VI). The experiments on microbial Cr(VI) reduction by S. putrefaciens were conducted in water, and the experiments on microbial Cr(VI) reduction by indigenous microorganisms, as well as the joint reduction of S. putrefaciens and indigenous microorganisms, were conducted in soil. The reactors were the same as those described in Section 2.3. In particular, no bacterial suspension was added to the reactors in the experiments focused on microbial Cr(VI) reduction by indigenous microorganisms. In the treatment setups, C8-HSL, C10-HSL, C12-HSL, 3OC8-HSL, 3OC10-HSL, and 3OC12-HSL were each introduced to a terminal level of 500 nmol·kg−1, while no AHLs were added to the controls. All experiments were conducted in triplicate. During incubation, samples were periodically collected inside an anaerobic glove box for Cr(VI) concentration measurement.

2.5. Analytical Methods

The extraction method of AHLs in soil was mainly based on the method of Li et al. [37] and optimized. Briefly, soil samples were suspended in deionized water and treated by an ultrasonic cell disruption system at a power of 150 W, and frequencies that were constant for 5 s and intermittent for 5 s for a total of 5 min. After undergoing centrifugation at 10,000 rpm for 10 min, the supernatant was taken as the AHLs extract. AHLs in the extract and water were concentrated by a solid-phase extractor [38], and detected by an ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) equipped with an electrospray ionization source (ESI) (LOD: 0.0092~0.0360 ng/L, LOQ: 0.0279~0.1225 ng/L, recovery rates: 75~98%) [39]. Alkaline digestion (EPA Method 3060A) was used to extract the total Cr(VI) in soil samples. Aqueous Cr(VI) was quantified using the diphenylcarbazide method at 540 nm with a UV/Vis spectrophotometer. The kinetics of Cr(VI) reduction were evaluated by fitting the data to pseudo-first-order and pseudo-second-order models (Equations (1) and (2)). All figures were generated using OriginPro 2021 9.8.0.200, with error bars representing the standard deviation (SD) of triplicate measurements. Statistical analysis was performed using one-way analysis of variance (ANOVA) in IBM SPSS Statistics 26.0. Where significant overall differences were detected, post hoc pairwise comparisons were conducted using the least significant difference (LSD) test. A significance threshold of p < 0.05 was applied for all statistical tests.
− d C r V I t d t = k 1 × [ C r ( V I ) ]
1 [ C r V I ] t − 1 [ C r V I ] 0 = k 2 × t
where k1 represents the first-order rate constant (d−1); k2 represents the second-order rate constant (d−1); [Cr(VI)]t represents the concentration of Cr(VI) at t time; and [Cr(VI)]0 represents the initial concentration of Cr(VI).

3. Results and Discussion

3.1. The Concentration of AHLs in the Cr(VI) Microbial Reduction

As the most extensively studied autoinducer, AHLs are also an important type of autoinducer in quorum sensing system of Gram-negative bacteria. They could be accurately determined by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Distinct AHLs profiles were observed across the three Cr(VI) reduction modes (Figure 1). During reduction driven by S. putrefaciens, the total AHL concentration reached 252.65 ng/L, with four species detected—C10-HSL (149.38 ng/L), 3OC8-HSL (15.17 ng/L), 3OC10-HSL (3.44 ng/L), and 3OC12-HSL (84.66 ng/L). In the system relying on indigenous microorganisms, the AHLs pool totaled 11.58 ng/L; six species were present: C8-HSL (5.05 ng/L), C10-HSL (3.27 ng/L), C12-HSL (0.11 ng/L), 3OC8-HSL (0.11 ng/L), 3OC10-HSL (0.05 ng/L), and 3OC12-HSL (2.92 ng/L). Under joint reduction by S. putrefaciens and the indigenous community, the total AHLs concentration was 37.91 ng/L, comprising five species: C8-HSL (5.91 ng/L), C10-HSL (1.09 ng/L), 3OC8-HSL (4.10 ng/L), 3OC10-HSL (2.29 ng/L), and 3OC12-HSL (24.51 ng/L).
The relatively higher concentration of total AHLs in the Cr(VI) reduction by S. putrefaciens may be due to the fact that it was conducted in water. There may be cheaters among indigenous microorganisms in Cr(VI)-contaminated soils, which would utilize AHLs but not contribute [40]. Indigenous microorganisms could also remediate Cr(VI)-contaminated soils owing to the presence of iron-reducing and Cr(VI)-reducing bacteria within the community [41]. During Cr(VI) reduction by native microorganisms, supplementation with S. putrefaciens would reduce the concentrations of C12-HSL to 0. This indicates that S. putrefaciens inhibits the release of AHLs by indigenous microorganisms.

3.2. The Effect of AHLs on Cr(VI) Microbial Reduction

3.2.1. Cr(VI) Reduction by Indigenous Microorganisms

Indigenous communities, which include iron-reducing and Cr(VI)-reducing taxa, can reduce Cr(VI) in soils [41]. Following amendment with sodium lactate and ferrihydrite, the Cr(VI) reduction rates by native microorganisms rose from 20.31% on day 7 to 47.33% on day 30 (Figure 2a). At day 30, exogenous AHLs exhibited divergent effects: C8-HSL, C12-HSL, and 3OC12-HSL significantly promoted the reduction rates by 4.10%, 3.05%, and 2.24% (p < 0.05), whereas C10-HSL, 3OC8-HSL, and 3OC10-HSL significantly suppressed them by 1.81%, 2.85%, and 4.96% (p < 0.05). Kinetic modeling yielded R2 values >0.95 for both pseudo-first-order and pseudo-second-order formulations, indicating that the temporal decline in Cr(VI) conformed to either model (Table 2; Figure 2b,c). Consistent with these fits, the estimated rate constants were higher than the control in treatments containing C8-HSL, C12-HSL, and 3OC12-HSL, but lower in those containing C10-HSL, 3OC8-HSL, and 3OC10-HSL. Overall, C8-HSL, C12-HSL, and 3OC12-HSL enhanced Cr(VI) reduction by indigenous microbes, whereas C10-HSL, 3OC8-HSL, and 3OC10-HSL exerted inhibitory effects.

3.2.2. Cr(VI) Reduction by S. putrefaciens in Soil

In the co-remediation system with S. putrefaciens and indigenous microorganisms, the control exhibited a Cr(VI) reduction rate of 34.01% on day 7 (Figure 3a). Relative to this control, additions of C8-HSL, C10-HSL, and C12-HSL significantly decreased the reduction rates by 24.37%, 22.33%, and 15.63% (p < 0.05). By day 15, the control reached 52.62%; under these conditions, C8-HSL, C12-HSL, and 3OC8-HSL significantly decreased the reduction rates by 15.50%, 9.34%, and 9.19% (p < 0.05). On day 30, the control achieved 83.66%, while C10-HSL and 3OC12-HSL significantly increased the reduction rates by 11.25% and 9.20%, and 3OC8-HSL significantly decreased it by 8.82% (p < 0.05). Kinetic analyses indicated a better fit to the pseudo-first-order model than to the pseudo-second-order model (higher R2; Table 2; Figure 3b,c). Consistently, first-order rate constants were elevated by C10-HSL, C12-HSL, 3OC10-HSL, and 3OC12-HSL relative to the control, but were reduced by C8-HSL and 3OC8-HSL. Overall, AHLs tended to suppress performance at early stages, whereas C10-HSL and 3OC12-HSL enhanced the final remediation outcome.

3.2.3. Cr(VI) Reduction by S. putrefaciens in Water

On day 18, the Cr(VI) reduction rate by S. putrefaciens reached 77.15% (Figure 4). Amendments with C8-HSL, C10-HSL, C12-HSL, and 3OC10-HSL increased the rate by 2.39%, 4.18%, 1.45%, and 2.71%, respectively, whereas 3OC8-HSL and 3OC12-HSL decreased it by 0.93% and 1.19%. Analysis of variance indicated that only C10-HSL and 3OC10-HSL exerted significant effects (p < 0.05).

3.3. The Role of AHLs Played in the Remediation

Based on the above results, it can be concluded that AHL-mediated quorum sensing played a role in microbial Cr(VI) reduction, both by S. putrefaciens and indigenous microorganisms, with specific AHLs demonstrating the ability to enhance Cr(VI) reduction efficiency. However, when they jointly reduced Cr(VI), such as in the remediation of Cr(VI)-contaminated soils, the effect of AHLs changed. C10-HSL could promote the Cr(VI) reduction by S. putrefaciens and inhibit the Cr(VI) reduction effect of indigenous microorganisms. Meanwhile, C10-HSL exerted a positive effect when they jointly reduced Cr(VI). This indicated that the promoting effect of C10-HSL on S. putrefaciens was greater than its inhibitory effect on indigenous microorganisms. Furthermore, 3OC12-HSL was found to enhance Cr(VI) reduction by indigenous microorganisms but had no significant effect on S. putrefaciens. This suggested that the improvement in remediation efficiency was primarily due to the stimulation of native microbial activity. As a result, both C10-HSL and 3OC12-HSL were able to promote the remediation effect of Cr(VI)-contaminated soil by S. putrefaciens.

4. Conclusions

In this study, the effect of exogenous AHLs on the remediation of Cr(VI)-contaminated soil by S. putrefaciens was investigated. Both S. putrefaciens and indigenous microorganisms could reduce Cr(VI), and there were multiple AHLs in this process, such as C8-HSL, C10-HSL, C12-HSL, 3OC8-HSL, 3OC10-HSL, and 3OC12-HSL. C8-HSL, C12-HSL, and 3OC12-HSL could promote the Cr(VI) reduction by indigenous microorganisms.
C10-HSL and 3OC10-HSL significantly enhanced the Cr(VI) reduction effect of S. putrefaciens. Furthermore, during the remediation of Cr(VI)-contaminated soil involving both S. putrefaciens and indigenous microorganisms, the addition of C10-HSL and 3OC12-HSL led to increased Cr(VI) reduction rates. Specifically, C10-HSL improved remediation performance by stimulating the Cr(VI) reduction effect of S. putrefaciens, whereas 3OC12-HSL enhanced the process by promoting reduction activity within the indigenous microbial community. This study demonstrates that modulating quorum sensing can effectively improve the microbial remediation of Cr(VI)-contaminated soil. AHLs are naturally signaling molecules that are ubiquitously produced and utilized by microorganisms in various environments. There are little environmental risks to the soil environment. It also provides a distinctive proposal for the microbial remediation of heavy metal-contaminated soils, and is conducive to further understanding the communication mechanism between exogenous and indigenous microorganisms in Cr (VI) reduction.

Author Contributions

X.Z.: Conceptualization, Methodology, Validation, Formal analysis, Investigation, Writing—Original Draft, Visualization; C.Z.: Formal analysis, Visualization; S.Z.: Validation, Investigation; D.Z.: Resources, Writing—Review and Editing, Supervision, Project administration. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the National Natural Science Foundation of China (No. 21656001).

Data Availability Statement

The raw data supporting the conclusions of this article will be made available by the authors on request.

Conflicts of Interest

The authors declare no conflict of interest.

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Processes 13 02931 g001aProcesses 13 02931 g001b
Figure 1. The concentrations (a) and percentages (b) of AHLs in the microbial Cr(VI) reduction.
Figure 1. The concentrations (a) and percentages (b) of AHLs in the microbial Cr(VI) reduction.
Processes 13 02931 g001aProcesses 13 02931 g001b
Processes 13 02931 g002aProcesses 13 02931 g002b
Figure 2. The effect of AHLs on Cr(VI) reduction by indigenous microorganisms (a) and kinetics of Cr(VI) reduction evaluated by fitting the data to pseudo-first-order (b) and pseudo-first-order (c).
Figure 2. The effect of AHLs on Cr(VI) reduction by indigenous microorganisms (a) and kinetics of Cr(VI) reduction evaluated by fitting the data to pseudo-first-order (b) and pseudo-first-order (c).
Processes 13 02931 g002aProcesses 13 02931 g002b
Processes 13 02931 g003aProcesses 13 02931 g003b
Figure 3. The influence of AHLs on Cr(VI) reduction by S. putrefaciens in soil (a) and kinetics of Cr(VI) reduction evaluated by fitting the data to pseudo-first-order (b) and pseudo-first-order (c).
Figure 3. The influence of AHLs on Cr(VI) reduction by S. putrefaciens in soil (a) and kinetics of Cr(VI) reduction evaluated by fitting the data to pseudo-first-order (b) and pseudo-first-order (c).
Processes 13 02931 g003aProcesses 13 02931 g003b
Processes 13 02931 g004
Figure 4. The effect of AHLs on the Cr(VI) reduction by S. putrefaciens (* represents a significant difference between the group and control at p < 0.05).
Figure 4. The effect of AHLs on the Cr(VI) reduction by S. putrefaciens (* represents a significant difference between the group and control at p < 0.05).
Processes 13 02931 g004
Table 1. Physicochemical properties of the soil sample.
Table 1. Physicochemical properties of the soil sample.
Soil TypeLoam Soil
pH b7.36 ± 0.06
Moisture content (%) a18.55% ± 0.43
Soil organic matter (g/kg) b9.75 ± 1.39
Cr(VI) concentration (mg/kg) b1383.06 ± 42.26
Values are means ± SD (n = 3). a Content of fresh matter. b Content of dry matter.
Table 2. The constants of first-order and second-order rate for Cr(VI) reduction.
Table 2. The constants of first-order and second-order rate for Cr(VI) reduction.
AHLsTime (d)Pseudo-First-OrderPseudo-Second-Order
k1 (d−1) aR2 bk2 (d−1) aR2 b
S. putrefaciensC80–300.0560 ± 0.00100.910.0038 ± 0.00090.82
C100.0906 ± 0.01770.890.0198 ± 0.00700.70
C120.0733 ± 0.01360.900.0086 ± 0.00280.74
3OC80.0492 ± 0.00510.970.0034 ± 0.00080.85
3OC100.0712 ± 0.00860.960.0065 ± 0.00190.78
3OC120.0881 ± 0.01770.890.0138 ± 0.00480.71
control0.0598 ± 0.00430.980.0045 ± 0.00120.83
controlC80.0235 ± 0.00130.990.0015 ± 0.00020.96
C100.0196 ± 0.00180.980.0014 ± 0.00010.97
C120.0227 ± 0.00160.990.0015 ± 0.00020.96
3OC80.0187 ± 0.00230.960.0013 ± 0.00010.96
3OC100.0179 ± 0.00220.960.0013 ± 0.00010.98
3OC120.0216 ± 0.00280.950.0015 ± 0.00020.95
control0.0204 ± 0.00210.970.0014 ± 0.00020.96
a Data are expressed as the mean ± standard error (n = 3). b The coefficient of determination (R2) was derived from the linear regression of ln([Cr]t/[Cr]0) against time during the spike period.
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MDPI and ACS Style

Zheng, X.; Zheng, C.; Zhou, S.; Zou, D. The Effect of Exogenous N-Acylated-L-Homoserine Lactones on the Remediation of Chromium-Contaminated Soil by Shewanella purefaciens. Processes 2025, 13, 2931. https://doi.org/10.3390/pr13092931

AMA Style

Zheng X, Zheng C, Zhou S, Zou D. The Effect of Exogenous N-Acylated-L-Homoserine Lactones on the Remediation of Chromium-Contaminated Soil by Shewanella purefaciens. Processes. 2025; 13(9):2931. https://doi.org/10.3390/pr13092931

Chicago/Turabian Style

Zheng, Xusheng, Chenglong Zheng, Shufang Zhou, and Dexun Zou. 2025. "The Effect of Exogenous N-Acylated-L-Homoserine Lactones on the Remediation of Chromium-Contaminated Soil by Shewanella purefaciens" Processes 13, no. 9: 2931. https://doi.org/10.3390/pr13092931

APA Style

Zheng, X., Zheng, C., Zhou, S., & Zou, D. (2025). The Effect of Exogenous N-Acylated-L-Homoserine Lactones on the Remediation of Chromium-Contaminated Soil by Shewanella purefaciens. Processes, 13(9), 2931. https://doi.org/10.3390/pr13092931

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