Diversity and Content of Carotenoids and Other Pigments in the Transition from the Green to the Red Stage of Haematococcus pluvialis Microalgae Identified by HPLC-DAD and LC-QTOF-MS

Abstract

H. pluvialis is a unicellular freshwater alga containing many bioactive compounds, especially carotenoids, which are the strongest antioxidants among the pigments. This study evaluates the composition and content of carotenoids and other pigments in both stages of algae life cycle, especially in the green vegetative stage, less studied in comparison to the red stage. To determine the composition and content of carotenoids, a combination of HPLC-DAD and LC-QTOF-MS was used. The content of carotenoids in the green vegetative stage was significantly lower than in the red vegetative stage. In the green vegetative stage, 16 different carotenoids and other pigments were identified. Among the total 8.86 mg g−1 DW of pigments, 5.24 mg g−1 DW or 59% of them were chlorophyll a with its derivatives, and 3.62 mg g−1 DW or 41% of them were free carotenoids. After the transition from the green to the red stage, the carotenoid composition was replaced by secondary carotenoids, astaxanthin and its esters, which predominated in the whole carotenoid composition. In addition to free astaxanthin, 12 astaxanthin monoesters, 6 diesters and 13 other carotenoids were determined. The majority of 37.86 mg g−1 DW pigments were monoesters. They represented 82% of all pigments, and their content was about 5 times higher than both, diesters (5.91 mg g−1 DW or 12% of all) and free carotenoids (2.4 mg g−1 DW or 6% of all). The results of the study contribute to the data on the overall pigment composition and content of H. pluvialis algae and provide the basis for further improvement of cultivation of the H. pluvialis algae.

Effect of light/dark cycles on the growth of Haematococcus pluvialis in mixotrophic cultivation with alternative culture media

“…In ME chlorophyll-a was low than the other culture media and the highest content was under 20/4 h light/dark cycle with 0.8±0.07 mgL -1 (Table 2). Chlorophyll-a is a primary light harvesting pigments, transfers excitation energy directly to the photosynthesis, and a green stage is indicated with the highest chlorophyll-a content (Grujić et al, 2022). In the current study chlorophyll-a was above 9 mgL -1 where dark period was absent (24/0 h), the opposite occurred with long dark period (12/12 h).…”

“…The first stage is called green stage, which has high cell yield and also play an important role in its further biosynthesis. The second stage can rapidly accumulate astaxanthin and is called red stage (Grujić et al, 2022).…”

Algal Carotenoids: Chemistry, Sources, and Application

“…Zhao et al [21] reported an extremely high concentration of astaxanthin in H. pluvialis (111.2 mg/g), Ishika et al [51] reported a similarly high concentration of fucoxanthin in Chaetoceros muelleri (2.92 mg/g), and Gayathri et al [26] reported similar results for lutein in Chlorella salina (2.76 mg/g). Other studies also reported the presence of other carotenoids in microalgae samples: β-carotene, adonixanthin, antheraxanthin, neoxanthin, and echinenone in H. pluvialis [59] and neoxanthin, violaxanthin, α-carotene, and β-carotene in Desmodesmus sp. F51 [58].…”

Sources, dynamics in vivo, and application of astaxanthin and lutein in laying hens: A review

“…Haematococcus pluvialis ( H. pluvialis ) exhibits a red color at its mature stage due to accumulated Ax. H. pluvialis has an excellent Ax content (55 mg/g of dry weight) and productivity, in particular, under environmental stress conditions ( Grujić et al., 2022 ; Todorović et al., 2021 ). Other strains with high Ax yields include Neochloris wimmeri , Protosiphon botryoides , and Scotiellopsis oocystiformis , which can produce 15 mg/g of dry biomass of Ax on average ( Barreiro and Barredo, 2018 ).…”

“… Main source Strain number Yield, mg/g Reference Astaxanthin content (≥20 mg/g of dry weight) in algae Haematococcus pluvialis CCALA 840 55 Todorović et al. (2021) H. pluvialis CCALA1081 46 Grujić et al. (2022) H. pluvialis LUGU (KM115647.1) 36 Yu et al.…”