1
|
Rana QUA, Latif S, Perveen S, Haq A, Ali S, Irfan M, Gauttam R, Shah TA, Dawoud TM, Wondmie GF, Bourhia M, Badshah M. Utilization of microalgae for agricultural runoff remediation and sustainable biofuel production through an integrated biorefinery approach. BIORESOUR BIOPROCESS 2024; 11:8. [PMID: 38647842 PMCID: PMC10992472 DOI: 10.1186/s40643-023-00720-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/18/2023] [Indexed: 04/25/2024] Open
Abstract
Generally wastewater such agricultural runoff is considered a nuisance; however, it could be harnessed as a potential source of nutrients like nitrates and phosphates in integrated biorefinery context. In the current study, microalgae Chlorella sp. S5 was used for bioremediation of agricultural runoff and the leftover algal biomass was used as a potential source for production of biofuels in an integrated biorefinery context. The microalgae Chlorella sp. S5 was cultivated on Blue Green (BG 11) medium and a comprehensive optimization of different parameters including phosphates, nitrates, and pH was carried out to acquire maximum algal biomass enriched with high lipids content. Dry biomass was quantified using the solvent extraction technique, while the identification of nitrates and phosphates in agricultural runoff was carried out using commercial kits. The algal extracted lipids (oils) were employed in enzymatic trans-esterification for biodiesel production using whole-cell biomass of Bacillus subtilis Q4 MZ841642. The resultant fatty acid methyl esters (FAMEs) were analyzed using Fourier transform infrared (FTIR) spectroscopy and gas chromatography coupled with mass spectrometry (GC-MS). Subsequently, both the intact algal biomass and its lipid-depleted algal biomass were used for biogas production within a batch anaerobic digestion setup. Interestingly, Chlorella sp. S5 demonstrated a substantial reduction of 95% in nitrate and 91% in phosphate from agricultural runoff. The biodiesel derived from algal biomass exhibited a noteworthy total FAME content of 98.2%, meeting the quality standards set by American Society for Testing and Materials (ASTM) and European union (EU) standards. Furthermore, the biomethane yields obtained from whole biomass and lipid-depleted biomass were 330.34 NmL/g VSadded and 364.34 NmL/g VSadded, respectively. In conclusion, the findings underscore the potent utility of Chlorella sp. S5 as a multi-faceted resource, proficiently employed in a sequential cascade for treating agricultural runoff, producing biodiesel, and generating biogas within the integrated biorefinery concept.
Collapse
Affiliation(s)
- Qurrat Ul Ain Rana
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
- Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Saira Latif
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Saleha Perveen
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Abdul Haq
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
- Peshawar Laboratories Complex, Pakistan Council of Scientific & Industrial Research, Islamabad, 25120, Pakistan
| | - Sidra Ali
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Muhammad Irfan
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | | | - Tawaf Ali Shah
- Collee of Agriculture Engineering and Food Sciences, Shandong University of Technology, Zibo, China
| | - Turki M Dawoud
- Department of Botany and Microbiology, College of Science, King Saud University, P. O. BOX 2455, 11451, Riyadh, Saudi Arabia
| | | | - Mohammed Bourhia
- Department of Chemistry and Biochemistry, Faculty of Medicine and Pharmacy, Ibn Zohr University, 70000, Laayoune, Morocco
| | - Malik Badshah
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320, Pakistan.
| |
Collapse
|
2
|
Maltsev Y, Kulikovskiy M, Maltseva S. Nitrogen and phosphorus stress as a tool to induce lipid production in microalgae. Microb Cell Fact 2023; 22:239. [PMID: 37981666 PMCID: PMC10658923 DOI: 10.1186/s12934-023-02244-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 11/04/2023] [Indexed: 11/21/2023] Open
Abstract
Microalgae, capable of accumulating large amounts of lipids, are of great value for biodiesel production. The high cost of such production stimulates the search for cultivation conditions that ensure their highest productivity. Reducing the content of nitrogen and phosphorus in the culture medium is widely used to change the content and productivity of lipids in microalgae. Achieving the right balance between maximum growth and maximum lipid content and productivity is the primary goal of many experimental works to ensure cost-effective biodiesel production from microalgae. The content of nitrogen and phosphorus in nutrient media for algal cultivation after converted to nitrogen (-N) and phosphorus (-P) lies in an extensive range: from 0.007 g L- 1 to 0.417 g L- 1 and from 0.0003 g L- 1 to 0.227 g L- 1 and N:P ratio from 0.12:1 to 823.33:1. When studying nutritional stress in microalgae, no single approach is used to determine the experimental concentrations of nitrogen and phosphorus. This precludes the possibility of correct interpretation of the data and may lead to erroneous conclusions. This work results from the systematisation of information on using nitrogen and phosphorus restriction to increase the lipid productivity of microalgae of different taxonomic and ecological groups to identify future research directions. The results of 301 experiments were included in the analysis using the principal components method. The investigation considered various divisions and classes: Cyanobacteria, Rhodophyta, Dinophyta, Haptophyta, Cryptophyta, Heterokontophyta/Ochrophyta (Bacillariophyceae, Eustigmatophyceae, Xanthophyceae), Chlorophyta, and also the ratio N:P, the time of the experiment, the light intensity during cultivation. Based on the concentrations of nitrogen and phosphorus existing in various nutrient media, a general scheme for designating the supply of nutrient media for nitrogen (as NO3- or NH4+, N g L- 1) and phosphorus (as РO4-, P g L- 1) has been proposed: replete -N (˃0.4 g L- 1), moderate -N (0.4-0.2), moderate N-limitation (0.19-0.1), strong N-limitation (˂0.1), without nitrogen (0), replete -Р (˃0.2), moderate -P (0.2-0.02), moderate P-limitation (0.019-0.01), strong P-limitation (˂0.01), without phosphorus (0).
Collapse
Affiliation(s)
- Yevhen Maltsev
- К.А. Timiryazev Institute of Plant Physiology RAS, IPP RAS, Moscow, 127276, Russia.
| | - Maxim Kulikovskiy
- К.А. Timiryazev Institute of Plant Physiology RAS, IPP RAS, Moscow, 127276, Russia
| | - Svetlana Maltseva
- К.А. Timiryazev Institute of Plant Physiology RAS, IPP RAS, Moscow, 127276, Russia
| |
Collapse
|
3
|
Microalga-Mediated Tertiary Treatment of Municipal Wastewater: Removal of Nutrients and Pathogens. SUSTAINABILITY 2021. [DOI: 10.3390/su13179554] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The microalgal strain Chlorella sorokiniana isolated from a waste stabilization pond was used for tertiary treatment of municipal wastewater. Three light:dark (L:D) regimes of 12:12, 16:8, and 24:0 were used for treating wastewater in microalga (A), microalga + sludge (A + S), and sludge (S) reactors. The removal of nutrients (N and P) was found to be the highest in the microalga-based reactor, with more than 80% removal of biochemical oxygen demand (BOD) and 1.2–5.6 log unit removal of pathogens. The addition of sludge improved chemical oxygen demand (COD) removal. Nitrifiers were found to be predominant in the A + S reactor. Algal biomass productivity was more than 280 mg/L/d in all the L:D regimes. The increase in light regime improved nutrient removal and biomass productivity in the algal reactor. Results of the kinetic study showed that (i) nitrifiers had more affinity for ammonium than microalga, and hence, most of the ammonia was oxidized to nitrate, (ii) microalga assimilated nitrate as the primary nitrogen source in the A + S reactor, and (iii) solubilization of particulate organic nitrogen originated from dead cells reduced the nitrogen removal efficiency. However, in the microalga-based reactor, the ammonium uptake was higher than nitrate uptake. Among pathogens, the removal of Salmonella and Shigella was better in the A + S reactor than in the other two reactors (microalga and sludge reactor). Additionally, the heterotrophic plate count was drastically reduced in the presence of microalga. No such drastic reduction was observed in the stand-alone sludge reactor. Kinetic modeling revealed that microalga–pathogen competition and pH-induced die-off were the two predominant factors for pathogen inactivation.
Collapse
|