Methods for Extraction, Isolation and Purification of C-phycocyanin: 50 years of research in review

Phycobiliproteins extract from Spirulina protects against single-dose cadmium-induced reproductive toxicity in male mice

Cadmium (Cd) is known for its many toxic effects on male population such as hypogonadism and fertility difficulties, which are oftenly associated with oxidative stress. As beneficial food, Spirulina(Sp) has been proved efficient against the heavy metal toxicity. This capacity can be associated with its phycobiliproteins (PBP). In this study, the capability of PBP and Sp to treat Cd-induced oxidative damage on the testes and spermatozoa was considered. CD-1 strain mice were orally treated with either Sp or PBP for 10 days prior to single-dose Cd challenge. Sperm quality determinations and testicle histology analysis were performed. Testosterone on serum was measured using enzyme-linked immunosorbent assay (ELISA). Oxidative damage was determined. Antioxidant enzyme activity was analyzed by measuring the activity of super oxide dismutase (SOD), catalase (Cat), and glutathione peroxidase (GpX). The motility and viability of sperm decrease with Cd and improve with PBP and Sp, as the acrosomal reaction (AR) is diminished by PBPs. Testosterone levels decrease due to Cd, and only Sp maintains elevated levels. Cd increases the production of malondialdehyde in the spermatozoa, but not in testes; this production of malondialdehyde in the spermatozoa decreases in the presence of PBP. ROS only decreases with Cd, FBP, and Sp at high concentrations. Advanced oxidative protein products (AOPP) decrease with Cd and PBPs. Cat and GpX increase their activity with Cd and are altered by FBP. Cd produces vascular alterations testes. Within the seminiferous tubule, it produces areas of necrosis and apoptosis, which improve with PBPs and Sp. PBPs have a strong antioxidant activity as they show protective properties against Cd oxidative-induced toxicity on testes and sperm.

Acclimation and Characterization of Marine Cyanobacterial Strains Euryhalinema and Desertifilum for C-Phycocyanin Production

This study involves evaluation of two native cyanobacterial strains Euryhalinema and Desertifilum isolated from a mangrove pond in Haikou (China) for their possible phycocyanin (C-PC) production. Maximal growth rate with highest chlorophyll and C-PC accumulation were observed at 28°C and 60 μmol photons m^-2 s^-1 photon flux density for Euryhalinema sp., while for Desertifilum sp. at 32°C and 80 μmol photons m^-2 s^-1. Nitrogen and iron concentration trails revealed that double strength concentration of sodium nitrate and ferric ammonium citrate in original BG11 media increased growth rate and accumulation of C-PC for both strains. Three different C-PC extraction methods were tested. The combined extraction protocol of freeze-thaw and ultrasonication markedly increased the C-PC extraction efficiency and attained the food grade purity (A ₆₂₀/A ₂₈₀ ratio >0.7), whereas a higher C-PC yield was found with Na-phosphate buffer. Furthermore, the clarified crude extract was used to purify C-PC by fractional ammonium sulfate [(NH₄)₂SO₄] precipitation, Sephadex G-25 gel filtration chromatography, and DEAE-sephadex ion exchange chromatography and attained analytical grade purity (A ₆₂₀/A ₂₈₀ ratio >3.9). Taken together, both strains showed their potential to be domesticated for valuable phycocyanin production.

Uncovering Research Trends of Phycobiliproteins Using Bibliometric Approach

Phycobiliproteins are gaining popularity as long-term, high-value natural products which can be alternatives to synthetic products. This study analyzed research trends of phycobiliproteins from 1909 to 2020 using a bibliometric approach based on the Scopus database. The current findings showed that phycobiliprotein is a burgeoning field in terms of publications outputs with "biochemistry, genetics, and molecular biology" as the most related and focused subject. The Journal of Applied Phycology was the most productive journal in publishing articles on phycobiliproteins. Although the United States of America (U.S.A.) contributed the most publications on phycobiliproteins, the Chinese Academy of Sciences (China) is the institution with the largest number of publications. The most productive author on phycobiliproteins was Glazer, Alexander N. (U.S.A.). The U.S.A. and Germany were at the forefront of international collaboration in this field. According to the keyword analysis, the most explored theme was the optimization of microalgae culture parameters and phycobiliproteins extraction methods. The bioactivity properties and extraction of phycobiliproteins were identified as future research priorities. Synechococcus and Arthrospira were the most cited genera. This study serves as an initial step in fortifying the phycobiliproteins market, which is expected to exponentially expand in the future. Moreover, further research and global collaboration are necessary to commercialize phycobiliproteins and increase the consumer acceptability of the pigments and their products.

Phycocyanin from Spirulina: A review of extraction methods and stability

Phycocyanin (C-PC) application by the industry is still limited due to extraction methods drawbacks and to the low stability of these compounds after the extraction process. To overcome such limitations, alternative extraction methodologies have been evaluated, and stabilizing agents have been used under different conditions in the past years. Therefore, the aim of this review was to bring the state of the art of C-PC extraction methods, including main parameters that affect the extraction process and cell disruption mechanisms, as well as the physical and chemical parameters that may influence C-PC stability. Stabilizing agents have been used to avoid C-PC content degradation during storage and food processing. A critical analysis of the extraction methods indicated that pulsed electric field (PEF) is a promising technology for C-PC extraction since the extracts present relative high C-PC concentration and purity. Other methods either result in low purity extracts or are time demanding. Regarding stabilizing agents, natural polymers and sugars are potential compounds to be used in food formulations to avoid color and antioxidant activity losses.

Optimization of the Freezing-Thawing Method for Extracting Phycobiliproteins from Arthrospira sp

The freezing-thawing method had been reported to be the best phycobiliprotein extraction technique. However, optimum parameters of this extraction method for Arthrospira sp. (one of the major phycobiliprotein sources) still remained unclear. Hence, this study aimed to optimize the freezing-thawing parameters of phycobiliprotein extraction in Arthrospira sp. (UPMC-A0087). The optimization of the freezing-thawing method was conducted using different solvents, biomass/solvent ratios, temperatures, time intervals and freezing-thawing cycles. The extracted phycobiliproteins were quantified using a spectrophotometric assay. Double distilled water (pH 7) with a 0.50% w/v biomass/solvent ratio was the most efficient solvent in extracting high concentrations and purity of phycobiliproteins from Arthrospira sp. In addition, the combination of freezing at -80 °C (2 h) and thawing at 25 °C (24 h) appeared to be the optimum temperature and extraction time to obtain the highest amount of phycobiliproteins. A minimum of one cycle of freezing and thawing was sufficient for extracting high concentrations of phycobiliproteins. The findings from this study could reduce the cost and labor needed for extracting high quality phycobiliproteins. It also allowed the harvesting of large amounts of valuable phycobiliproteins.

Effect of liquid fermentation on bread fortified with Lycium ruthenicum: A quality attribute and in vitro digestibility study

The aim of this study was to research the effect of yeast fermentation on the polyphenol content of Lycium ruthenicum (LR) to guide the production of bread with a lower digestibility. Liquid fermentation from 0 to 2 h significantly increased the phenolic, flavonoid and anthocyanin content of LR, while further liquid fermentation from 2 to 16 h had little additional effect. The addition of LR without prior liquid fermentation impaired the bread quality, while a prior liquid fermentation for at least 2 h improved the bread quality. The bread digestibility was decreased after adding LR, and it was further reduced with the extended liquid fermentation time. The results of this study indicate that adding LR with prior liquid fermentation to the dough during bread making could result in a higher quality and a lower digestibility.