ABSTRACT
PURPOSE: In this study, the optimization of extraction process parameters of caffeic acid content from Spirulina platensis is performed by supercritical green technology. METHODS: Especially, the optimization of supercritical carbon dioxide (SC-CO2) extraction parameters was carried out employing Box-Behnken design (BBD) and response surface methodology (RSM). Alongside, the three levels of extraction parameters i.e. extraction pressure, extraction time and temperature have been fixed. As a response, the caffeic acid content of the extracts was determined by HPLC. The statistical analysis (ANOVA) of developed mathematical models was used in the process. RESULTS: The extract exhibited the highest content of caffeic acid as 72.11 µg/g of dw at the optimized extraction conditions of 360.08 bar pressure for 57.13 min extraction time at 38.31 °C temperature. Simultaneously this extract exhibited the highest content of total phenolic content (76.87 µg GAE/g dw), reducing power (2278 µg BHT/g dw), FRAP value (4.19 mM FeSO4 equivalent/g dw) and IC50 for DPPH activity (89.28 µg/mL). CONCLUSION: It has been also noted that supercritical fluid extract can significantly retard the growth of microorganisms in litchi beverage. Consequently, we can also predict that isolated SC-CO2 antioxidant containing fraction would have hopeful for foodstuff preservative.
ABSTRACT
Wastewater imposes a great threat to any ecosystem across the world, especially the aquatic one because of the different anthropogenic activities of human beings. The present study emphasizes the optimization of ecological parameters [pH, time (h) and temperature (°C)] employing Box-Behnken design (BBD) to achieve better bio-adsorption of a selected heavy metal [lead (Pb II)] from the wastewater through an extracellular polymeric substance (EPS) of a benthic fungus, Aspergillus penicillioides (F12) (MN210327). The relevant statistical analysis (ANOVA) has enabled to record of the optimized bio-adsorption (73.14 %) of lead (Pb II) by fungal EPS at pH (8.85) and temperature (32 °C) for a duration of 5.74 h. Besides that, at the concentration of 0.5 mg/L of EPS, the flocculating rate was noted to be highest (88.4 %) in kaolin clay and the 50 % emulsifying activity. This investigation has also opened up new vistas on the possibility of the development of an alternative method of eco-sustainable bioremediation of heavy metals by fungal EPS on an industrial scale.
Subject(s)
Extracellular Polymeric Substance Matrix , Metals, Heavy , Adsorption , Aspergillus , Ecosystem , Fungi , Humans , LeadABSTRACT
Since the birth of Christ, in these 2019 years, the man on earth has never experienced a survival challenge from any acellular protist compared to SARS-CoV-2. No specific drugs yet been approved. The host immunity is the only alternative to prevent and or reduce the infection and mortality rate as well. Here, a novel mechanism of melanin mediated host immunity is proposed having potent biotechnological prospects in health care management of COVID-19. Vitamin D is known to enhance the rate of melanin synthesis; and this may concurrently regulate the expression of furin expression. In silico analyses have revealed that the intermediates of melanin are capable of binding strongly with the active site of furin protease. On the other hand, furin expression is negatively regulated via 1-α-hydroxylase (CYP27B1), that belongs to vitamin-D pathway and controls cellular calcium levels. Here, we have envisaged the availability of biological melanin and elucidated the bio-medical potential. Thus, we propose a possible synergistic application of melanin and the enzyme CYP27B1 (regulates vitamin D biosynthesis) as a novel strategy to prevent viral entry through the inactivation of furin protease and aid in boosting our immunity at the cellular and humoral levels.
