Year: 2023
Type: dissertation
Abstract: Most of the synthetic pigments commercially used these days in the development of dyes, paints, cosmetics, or other similar applications, tend to be harmful for the human health and for the environment. Some of them can even inhibit the absorption of nutrients and may cause allergic reactions. Furthermore, the use of sustainable chemicals as colourants is very limited due to the lack of alternatives and variety of shades. Therefore, there is a growing need for eco-friendly pigments obtained from natural and renewable resources, for them to be used as alternatives both in biotechnological and pharmaceutical applications, as well as in the cosmetic, food or paint industry. One promising candidate for such requirements are the accessory photosynthetic pigments, phycobiliproteins, that are embodied in a light-harvesting protein complex called phycobilisome, present in the photoautotrophic, gram-negative prokaryotes named cyanobacteria. The most common phycobiliproteins are phycocyanin, allophycocyanin and phycoerythrin, which are characterized by their intense colour, fluorescence and for their beneficial effects as antioxidant, anticancer, neuroprotectors, etc. This study focuses on maximizing the production of these pigments in microbiomes rich in cyanobacteria. A microbiome is a collection of microbes, such as bacteria, fungi, virus that occur in nature in all different habitat. The microbiomes studied in the present work were obtained from natural environments and enriched in cyanobacteria by strategies of phosphorous limitation. The effect of different factors, namely days of exposure and exposure to different wavelengths were studied with the aim of maximizing the biomass production, phycobiliprotein accumulation and therefore, the productivity of these microbiomes. The experimental conditions and data analysis were developed by an experimental design software called JMP Pro. The results revealed that while the light quality had an impact on the biomass and phycobiliprotein production of both Synechococcus sp. and microbiomes, the time of exposure solely influenced the productivity of Synechococcus sp. Furthermore, the most favourable settings for maximizing phycobiliprotein recovery in each microbiome were determined using JMP Pro.
Author: Alam Fatima, Sara Azhar
Language: English
Subfield: Biotechnology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W6995626339