Antibacterial and photocatalytic potential of bioactive compounds extracted from freshwater microalgae species (Spirogyra and Ocillatoria): A comparative analysis.

Water pollution by pathogenic bacteria and organic dyes poses potential health hazards for human and aquatic life. This study aims to explore the potential of bioactive compounds extracted from two microalgae species (Spirogyra and Ocillatoria) for water pollution control. The optimization of the extraction process for bioactive compounds resulted in the highest yield at 25 min for Spirogyra and 30 min for Ocillatotia species. Further, the extracted bioactive compounds were analyzed using Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC-MS). The bioactive compounds exhibited significant antibacterial activity against gram-positive and gram-negative bacteria. Notably, Spirogyra species exhibited a higher zone of inhibition (19.5-20.7 mm) than Ocillatoria species (17.0-18.0 mm) against both gram-positive and gram-negative bacterial strains. Furthermore, the photocatalytic potential of these bioactive compounds was examined by assessing the photodegradation of methylene blue (MB) and crystal violet (CV) dyes under different light sources. The findings revealed that Spirogyra species exhibited better photocatalytic activity than Ocillatoria species for MB and CV. For MB, 89.75 %, 77.82 % and 63.54 % were photodegraded when exposed to UV light, sunlight and visible light using Spirogyra extract, compared to 84.90 %, 74.70 % and 58.30 % by Ocillatoria extract. Regarding CV, Spirogyra extract achieved photodegradation efficiency of 88.94 %, 76.59 % and 64.50 % under UV light, sunlight and visible light, higher than 83.60 %, 73.60 % and 57.70 % by Ocillatoria extract. Both Spirogyra and Ocillatoria species demonstrated the best performance for dye photodegradation under UV irradiation, demonstrating great potential for nature-based water treatment.

Anti-obesity efficacy of the selected high altitude Himalayan herbs: in vitro studies.

Obesity is a serious health problem for all age groups and it also promotes Type 2 diabetes, cardiovascular diseases, cancer and hypertension. Herbs are used for the weight reduction from ancient times, therefore, 12 herbs viz. Betula utilis, Bunium periscum, Angelica glauce, Saussurea lappa, Podophyllum hexandrum, Bergenia ciliate, Rumex acetosa, Aconitum heterophyllum, Centella asiatica, Andrographis paniculata, Dactylorhiza hatagirea and Bauhina variegate were selected as per literature. Rumex acetosa roots showed the highest extraction rate (39.5%), while C. asiatica leaf showed lowest extraction rate (1.25%) as compared to other herbs. As well, S. lappa leaf extract (396.52 mg GAE/g), R. acetosa root extract (181.5 mg QE/g), and B. ciliate leaf extract (79.19%) showed significantly higher Total Phenolic Content, Total Flavonoid Content and antioxidant activity, respectively. Furthermore, lipase and amylase inhibition activity and IC50 value of herb extract were higher in S. lappa root extract (75.75%, 75.41% and 62.47, 61.37, respectively). Bauhina variegate leaf extract showed a significantly higher glucose level, percentage of glucose movement (1.446 mg/dL and 63.85%) and (0.938 mg/dL and 76.55%). Based upon these experiments, 5 herbs were selected and different formulations were prepared and out of these, F3 herb formulation showed higher lipase and amylase inhibition activity (81.75% and 70.66%) and therefore, F3 herbal formulation was selected for treatment of obesity.