Potential Efficiency of Green Algae Scenedesmus quadricauda In Bio­Remediation Of Polycyclic Aromatic Hydrocarbon Benzo [a] Pyrene (BaP)

Abstract

Using algae to break down or detoxify dangerous environmental pollutants thereby changing them into a non-hazardous condition is known as bioremediation. Investigating the ability of the green algae Scenedesmus quadricauda (Turpin) Brébisson to breakdown a particular polycyclic aromatic hydrocarbon (PAH) known as Benzo a pyrene (BaP), Under regulated laboratory circumstances and on BG11 media, the alga was cultivated and exposed to different BaP dosages (1, 0.5, and 1.5 mM.). High performance liquid chromatography (HPLC) study helped to ascertain the BaP concentration. Involving as the growth curve, doubling time, photosynthetic pigments, total protein, carbohydrates, and MDA levels, the research investigated various physiological and biochemical aspects. Furthermore measured were the levels of catalase (CAT), superoxide dismutase (SOD), and reactive oxygen species (ROS). Whereas the lowest growth rate was 0.00047 on the 15th day at an amount of 1.5 mM, the maximum growth rate (k) recorded was 0.391 on the 7th day at an amount of 0.5 mM. Doubling time also varied from 0.00014 throughout 15th day with 1.5 mM and from 0.1179 throughout 7th day with 0.5 mM BaP. The results showed a definite influence of different quantity of BaP degradation by S. quadricauda; the greatest magnitude was 40.13 throughout 15th with 0.5 mg/l, while the lowest magnitude was 0 throughout 1st day with 0.5 Mm. While the min magnitude 0.41µg/ml in 0.5 mM throughout 1st day, the max magnitude of chlorophyll-a was 18.71 (µg/ml) in 1.5 mM throughout 15th day. Whereas the greatest magnitude was 9.19 µg/ml in 1.5 mM throughout 15th day, the lowest magnitude of chlorophyll b was to 0.36 µg/ml in 1.5 mM throughout 1st day. While the min was 0.013 on 1st day with 1mM, the max magnitude of ROS was 0.28 until 15th day with 1.5 mM. With 1mM over 1st day, the carbohydrate showed a max magnitude of 35.13 µm/ml; with 1.5 mM over 15th day, the min magnitude was 12.25(µm/ml). While the min protein content 1.83 µg/ml in 1.5 Mm throughout 8th day, the max protein content was 2.14 µg/ml in 1 mM throughout 8th day, Moreover, SOD fluctuated between 22.22 µg/ml in 0.5 mM throughout 1st day, and 60µg/ml in as the min magnitude throughout 8th day with 1.5 mM. The results show that magnitudes of CAT fluctuated between 13.33µg/ml in 8th and 15th mM throughout 15th day and 73.33µg/ml in 1mM throughout 15th day. MDA showed the largest magnitude—59.92 µmol/l in 1.5 mM over 1st day—while the lowest magnitude, 36.58 µmol/l in 1mM over 15th day.