ABSTRACT
Microalgal species from sewage treatment plant were identified by 18S rRNA sequencing and were explored for total lipids, carbohydrate, and protein contents, to serve as a potential candidate for biorefinery. Seven unicellular microalgae were identified as Chlorella sorokiniana, Dictyosphaerium sp., Graesiella emersonii belonging to Chlorellaceae and Scenedesmus sp., Desmodesmus sp., Tetranephris brasiliensis, and Coelastrella sp. belonging to Scenedesmaceae family. Biochemical assessment of all isolates revealed total lipid content from 17.49 ± 1.41 to 47.35 ± 0.61% w/w, total carbohydrate content from 12.82 ± 0.19 to 64.29 ± 0.63% w/w, and total protein content from 8.55 ± 0.19 to 16.65 ± 0.20% w/w. FAME analysis of extracted lipid was found to be rich in Hexadecane (C16:0), Tetradecane (C17:0), Octadecane (C18:0), Eicosane (C20:0), Tetracosane (C24:0), Pentacosane (C25:0) fatty acids, the presence of which makes excellent candidate for biodiesel. Being rich in lipid, microalgae Chlorella sorokiniana, Coelastrella sp., and Scenedesmus sp. have high potential for biofuels. Due to the presence of high protein content, Scenedesmus sp. and Chlorella sorokiniana can serve as food or feed supplement, whereas the high carbohydrate content of Dictyosphaerium sp., Coelastrella sp., and Scenedesmus sp. makes them an ideal candidate for fermentative production of alcohol and organic acids. Chlorella sp. and Scenedesmus sp., being dominant microalgae across all seasons, demonstrate remarkable resilience for their cultivation in sewage water and utilization of biomass in biorefineries.
ABSTRACT
Precision agriculture is crucial for ensuring food security in a growing global population. Nutrients, their presence, concentration, and effectiveness, are key components in data-driven agriculture. Assessing macro and micro-nutrients, as well as factors such as water and pH, helps determine soil fertility, which is vital for supporting healthy plant growth and high crop yields. Insufficient soil nutrient assessment during continuous cropping can threaten long-term agricultural viability. Soil nutrients need to be measured and replenished after each harvest for optimal yield. However, existing soil testing procedures are expensive and time-consuming. The proposed research aims to assess soil nutrient levels, specifically nitrogen and phosphorus concentrations, to provide critical information and guidance on restoring optimal soil fertility. In this research, a novel chip-level colorimeter is fabricated to detect the N and P elements of soil onto a handheld colorimeter or spectrophotometer. Chemical reaction with soil solution generates color in the presence of nutrients, which are then quantitatively measured using sensors. The test samples are collected from various farmlands, and the results are validated with laboratory analysis of samples using spectrophotometers used in laboratories. ANOVA test has been performed in which F value > 1 in our study indicates statistically significant differences between the group means. The alternate hypothesis, which proposes the presence of significant differences between the groups, is supported by the data. The device created in this paper has crucial potential in terms of environmental and biological applications.
Subject(s)
Phosphorus , Soil , Farms , Phosphorus/analysis , Nitrogen/analysis , Agriculture/methods , Fertilizers/analysisABSTRACT
Hydrothermal liquefaction (HTL) is identified as a promising thermochemical technique to recover biofuels and bioenergy from waste biomass containing low energy and high moisture content. The wastewater generated during the HTL process (HTWW) are rich in nutrients and organics. The release of the nutrients and organics enriched HTWW would not only contaminate the water bodies but also lead to the loss of valued bioenergy sources, especially in the present time of the energy crisis. Thus, biotechnological as well as physicochemical treatment of HTWW for simultaneous extraction of valuable resources along with reduction in polluting substances has gained significant attention in recent times. Therefore, the treatment of wastewater generated during the HTL of biomass for reduced environmental emission and possible bioenergy recovery is highlighted in this paper. Various technologies for treatment and valorisation of HTWW are reviewed, including anaerobic digestion, microbial fuel cells (MFC), microbial electrolysis cell (MEC), and supercritical water gasification (SCWG). This review paper illustrates that the characteristics of biomass play a pivotal role in the selection process of appropriate technology for the treatment of HTWW. Several HTWW treatment technologies are weighed in terms of their benefits and drawbacks and are thoroughly examined. The integration of these technologies is also discussed. Overall, this study suggests that integrating different methods, techno-economic analysis, and nutrient recovery approaches would be advantageous to researchers in finding way for maximising HTWW valorisation along with reduced environmental pollution.
