Ekstrem Bor Konsantrasyonlarında Lemna minor ile Acil Durum Fitoremediasyonu: Toksisite Sınırlarını Aşan Bir Yaklaşım

Öz

Bor, çeşitli endüstriyel faaliyetler nedeniyle sucul ortamlarda birikerek toksik etkilere yol açabilmektedir. Bu çalışma, geleneksel toksik sınırların çok üzerindeki bor konsantrasyonlarında, acil durum müdahalesi için Lemna minor’un bor birikim (akümülasyon) kapasitesini değerlendirmektedir. Bu amaçla Lemna minor bitkisinin 300–3000 mg/L bor konsantrasyonlarına 7 gün süreli maruziyeti sonucunda gösterdiği büyüme tepkisi, bor birikimi ve fizyolojik değişimleri değerlendirilmiştir. Araştırma kapsamında RGR (relatif büyüme hızı), klorofil içeriği, biyokonsantrasyon faktörü (BCF), çözeltide kalan bor oranları ve bitkinin biriktirdiği bor miktarı analiz edilmiştir. Sonuçlar, bitki büyümesinin ve klorofil sentezinin yüksek bor seviyelerinde baskılandığını, ancak Lemna minor’un ekstrem bor konsantrasyonlarında dahi etkili bor birikimi gerçekleştirebildiğini ve artan çözelti bor konsantrasyonuna bağlı olarak bor birikiminin anlamlı şekilde arttığını göstermiştir. 3000 ppm ekstrem bor seviyede yaklaşık 39 mg/g DW birikim gözlemlenmiştir. 300 ppm bor çözeltisinde deney sonunda 28,9 (L/kg) maksimum BCF değerine ulaşılmıştır. Elde edilen bulgular, Lemna minor’un toksisite sınırlarını aşan bor konsantrasyonlarında dahi, bitki sağlığının korunmasının öncelikli olmadığı, ancak hızlı bor gideriminin gerekli olduğu durumlarda sınırlı sürelerle etkili bir fitoremediasyon ajanı olarak kullanılabileceğini göstermektedir.

Anahtar Kelimeler

• fitoremediasyon
• Lemna minor
• bor
• BCF
• klorofil
• RGR.

Emergency Phytoremediation with Lemna minor at Extreme Boron Concentrations: An Approach Beyond Toxicity Limits

Öz

Boron accumulation in aquatic environments due to various industrial activities can lead to severe toxicity. This study evaluates the boron accumulation capacity of Lemna minor for emergency response scenarios at boron concentrations far exceeding traditional toxicity limits. For this purpose, the growth inhibition, boron accumulation, and physiological responses of Lemna minor were evaluated during a 7-day exposure to boron concentrations of 300–3000 mg/L. Parameters such as relative growth rate (RGR), chlorophyll content, bioconcentration factor (BCF), residual boron ratios and the amount of boron accumulated by the plant were evaluated. The results indicated that while plant growth and chlorophyll synthesis were suppressed at high boron levels, Lemna minor demonstrated effective boron accumulation even at extreme concentrations, and boron accumulation significantly increased with rising solution concentrations. The highest boron accumulation of approximately 39 mg/g dry weight (DW) was observed at the extreme boron level of 3000 mg/L and a maximum BCF value of 28.9 L/kg was achieved in the 300 mg/L boron solution. These findings suggest that Lemna minor can serve as an effective phytoremediation agent for limited periods in situations requiring rapid boron uptake, even at concentrations exceeding toxicity limits where preserving plant health is not the primary priority.

Anahtar Kelimeler

• phytoremediation; Lemna minor; boron; BCF; chlorophyll; RGR.

Kaynakça

1. Duman MV, Özmetin E. Boron removal from waste water originating in the open pit mines of Bigadiç Boron Work by means of reverse osmosis. International Journal of Global Warming 2014; 6: 252-269.
2. Isa MH, Ezechi EH, Ahmed Z, Magram SF ve Kutty SRM. Boron removal by electrocoagulation and recovery. Water Research 2014; 51: 113-123.
3. Yuce G, Yasin D. Assessment of an Increase in Boron and Arsenic Concentrations at the Discharge Area of Na-Borate Mine (Kirka-Eskisehir, Turkey). Terrestrial, Atmospheric and Oceanic Sciences 2012; 23: 703-723.
4. Zhao S, Huq ME, Fahad S, Kamran M, ve Riaz M. Boron toxicity in plants: understanding mechanisms and developing coping strategies; a review. Plant Cell Rep 2024; 43: 238.
5. Türker OC, Yakar A ve Gür N. Bioaccumulation and toxicity assessment of irrigation water contaminated with boron (B) using duckweed (Lemna gibba L.) in a batch reactor system. Journal of Hazardous Materials 2017; 324: 151-159.
6. Kuru R, Yilmaz S, Sacan O, Yanardag R, Yarat A, ve Sahin F. Boron concentrations in tap water in many cities of Turkey. Toxicological & Environmental Chemistry 2020; 102: 240-249.
7. World Health Organization, Guidelines for drinking-water quality: fourth edition incorporating first addendum, 4th ed., 1st add. Geneva: World Health Organization, 2017.
8. Mutlu-Salmanli O, Koyuncu I. Boron removal and recovery from water and wastewater. Rev Environ Sci Biotechnol 2022; 21(3): 635-664.

9. Del-Campo Marín CM, Oron G. Boron removal by the duckweed Lemna gibba: A potential method for the remediation of boron-polluted waters. Water Research 2007; 41: 4579-4584.
10. Mutlu-Salmanli O, Kazak A, Turken T, Pasaoglu ME, Zeytuncu B, Koyuncu I. Boron removal and recovery via vacuum assisted air gap membrane distillation-crystallization (VAGMD-C): A pilot-scale study. Desalination 2023; 547: 116229.
11. Zeytuncu B, Pasaoglu ME, Eryildiz B, Kazak A, Yuksekdag A, Korkut S, Kaya R, Turken T ve diğerleri. Application of different treatment systems for boron removal from industrial wastewater with extremely high boron content. Journal of Water Process Engineering 2023; 55: 104083.
12. Yan A, Wang Y, Tan SN, Mohd Yusof ML, Ghosh S, Chen Z. Phytoremediation: A Promising Approach for Revegetation of Heavy Metal-Polluted Land. Front. Plant Sci 2020; 11: 513099.
13. Sree K, Bog M, Appenroth K. Taxonomy of duckweeds (Lemnaceae), potential new crop plants. Emir. J. Food Agric 2016; 28(5): 291.
14. Rai PK. Heavy Metal Pollution in Aquatic Ecosystems and its Phytoremediation using Wetland Plants: An ecosustainable approach. International Journal of Phytoremediation 2008; 10(2): 133-160.
15. Böcük H, Yakar A, ve Türker OC. Assessment of Lemna gibba L. (duckweed) as a potential ecological indicator for contaminated aquatic ecosystem by boron mine effluent. Ecological Indicators 2013; 29: 538-548.
16. Gür N, Türker OC, ve Böcük H. Toxicity assessment of boron (B) by Lemna minor L. and Lemna gibba L. and their possible use as model plants for ecological risk assessment of aquatic ecosystems with boron pollution. Chemosphere 2016; 157: 1-9.
17. Liu C, Gu W, Dai Z, Li J, Jiang H, Zhang Q. Boron accumulation by Lemna minor L. under salt stress. Sci Rep 2018; 8(1): 954.
18. Ökten HE, Gören AY. Phytoremediation of Boron using Lemna minor from Synthetic Aqueous Solutions and Real Geothermal Water. Süleyman Demirel Üniversitesi Fen Bilimleri Enstitüsü Dergisi 2021; 25(2): 217-228.
19. Tatar ŞY, Öbek E. Potential of Lemna gibba L. and Lemna minor L. for accumulation of Boron from secondary effluents. Ecological Engineering 2014; 70: 332-336.
20. Cui R, Kwak JI, An YJ. Understanding boron toxicity in aquatic plants (Salvinia natans and Lemna minor) in the presence and absence of EDTA. Aquatic Toxicology 2024; 269: 106886.
21. Zhao Q, Li J, Dai Z, Ma C, Sun H, Liu C. Boron tolerance and accumulation potential of four salt-tolerant plant species. Sci Rep 2019; 9(1): 6260.
22. Stiles AR, Bautista D, Atalay E, Babaoğlu M, Terry N. Mechanisms of Boron Tolerance and Accumulation in Plants: A Physiological Comparison of the Extremely Boron-Tolerant Plant Species, Puccinellia distans, with the Moderately Boron-Tolerant Gypsophila arrostil. Environ. Sci. Technol 2010, 44(18): 7089-7095.
23. Sitarska M, Traczewska T, Filarowska W, Hołtra A, Zamorska-Wojdyła D, Hanus-Lorenz B. Phytoremediation of mercury from water by monocultures and mixed cultures pleustophytes. Journal of Water Process Engineering 2023; 52: 103529.
24. Daud MK, Ali S, Abbas Z, Zaheer IE, Riaz MA, Malik A, Hussain A, Rizwan M, Zia-ur-Rehman M, Zhu SJ. Potential of Duckweed (Lemna minor) for the Phytoremediation of Landfill Leachate. Journal of Chemistry 2018; 2018(1): 3951540.
25. Chaudhary E, ve Sharma P. Chromium and cadmium removal from wastewater using duckweed - Lemna gibba L. and ultrastructural deformation due to metal toxicity. International Journal of Phytoremediation 2019; 21(3): 279-286.
26. O’Mahoney R, Coughlan NE, Walsh É, Jansen MAK. Cultivation of Lemna Minor on Industry-Derived, Anaerobically Digested, Dairy Processing Wastewater. Plants 2022; 11(22): 3027.
27. Villavicencio MS, Silva CÁ, Arce GM. Boron toxicity in Lemna gibba. Hidrobiologica 2007; 17: 1-6.
28. Kayıhan DS, Kayıhan C, Çiftçi YÖ. Excess boron responsive regulations of antioxidative mechanism at physio-biochemical and molecular levels in Arabidopsis thaliana. Plant Physiology and Biochemistry 2016; 109: 337-345.
29. Dağlioğlu Y, Türki̇Ş S. A Comparative Study on the Effect of Acute Toxicity of Nano and Micro Boron Particles in Lemna minor (Linneaus 1753)”, Journal of Boron 2021; 6(2): 263-273.
30. Türker OC, Yakar A, Türe C, Saz Ç. Boron (B) removal and bioelectricity captured from irrigation water using engineered duckweed-microbial fuel cell: effect of plant species and vegetation structure. Environ Sci Pollut Res Int 2019; 26(30): 31522-31536.