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Bioactive compounds extracted from natural renewable sources have attracted an increased interest from both industry and academia. Recently, algae have been highlighted as promising sources of bioactive compounds, such as polyphenols, polysaccharides, fatty acids, proteins, and pigments, which can be used as functional ingredients in many industrial applications. Therefore, a simple green extraction and purification methodology capable of recovering biocompounds from algal biomass is of extreme importance in commercial production. In this study, we evaluated the application of three valuable algae (Colaconema formosanum, Sarcodia suae, and Nostoc commune) in combination with Pseudoalteromonas haloplanktis (type strain ATCC 14393) for the production of versatile compounds. The results illustrate that after 6 h of first-stage fermentation, the production of phycobiliproteins in C. formosanum was significantly increased by 156.2%, 188.9%, and 254.17% for PE, PC, and APC, respectively. This indicates that the production of phycobiliproteins from algae can be enhanced by P. haloplanktis. Furthermore, we discovered that after S. suae and N. commune were fermented with P. haloplanktis, mannose was produced. In this study, we describe a feasible biorefinery process for the production of phycobiliproteins and mannose by fermenting marine macroalgae with cyanobacteria. We believe it is worth establishing a scale-up technique by applying this fermentation method to the production of phycobiliproteins and mannose in the future.

Ultraviolet (UV-C) irradiation is the most important part of water filtration, which has no side effects on the environment and has been used in water purification systems in the aquaculture and transistor industries. In this research, the effect of UV-C on Chlorella sp. was investigated. Chlorella sp. was irradiated 0, 1, 2 or 3 times at a fixed flow rate of 6.5 L min−1 and the effects of UV-C LED on the apoptosis rate and death rate of Chlorella sp. were analyzed by flow cytometry after staining cells with the nucleic acid dye SYTOX Green and the membrane-associated protein stain Annexin V-PE Reagent. As a result of UV-C irradiation, the Chlorella sp. cells underwent phosphatidylserine (PS) ectropion and plasma membrane damage, which resulted in death. The effect of UV-C was proportional to the number of times of irradiation. Three doses of UV-C LED irradiation resulted in a 91.76 ± 3.33% death rate, as observed through SYTOX Green staining, with no rebound within 72 h. This research is the first report to observe that delayed cellular apoptosis occurred in Chlorella sp., and we expect that our study can be used as a standard reference for future industrial applications.

We investigated whether phycoerythrin (PE), a pigment sourced from marine algae, could act as an immunomodulatory agent in whiteleg shrimp (Litopenaeus vannamei). To this end, PE was extracted and purified from a PE-rich macroalgae, Colaconema sp. Our in vitro analysis demonstrated that PE enhanced prophenoloxidase and phagocytosis activity but inhibited the production of reactive oxygen species in hemocytes. Additionally, the PE signal could be detected using an in vivo imaging system after its injection into the ventral sinus of the cephalothorax of whiteleg shrimp. The expression profiles of fourteen immune-related genes were monitored in hemocytes from whiteleg shrimp injected with 0.30 μg of PE per gram of body weight, and crustin, lysozyme, penaiedin 4, and anti-lipopolysaccharide factor showed up-regulated post-stimulation. The induction of immune genes and enhancement of innate immune parameters by PE may explain the higher survival rates for shrimp that received different doses of PE prior to being challenged with Vibrio parahaemolyticus or white spot syndrome virus compared to controls. Combined, these results show that PE from Colaconema sp. can differentially stimulate the immune response of whiteleg shrimp in vitro and in vivo and could potentially be used as an immunomodulator in shrimp culture.

OBJECTIVES:Respiration-induced motion in the liver causes potential errors on the measurement of contrast medium in abdominal artery from multiphase hepatic CT scans. In this study, we investigated the use of hepatic CT images to quantitatively estimate the abdominal artery motion due to respiration by optical flow method. MATERIALS AND METHODS:A total of 132 consecutive patients were included in our patient cohort. We apply the optical flow method to compute the motion of the abdominal artery due to respiration. RESULTS:The minimum and maximum displacement of the abdominal artery motion were 0.02 and 30.87 mm by manual delineation, 0.03 and 40.75 mm calculated by optical flow method, respectively. Both high consistency and correlation between the present method and the physicians' manual delineations were acquired with the regression equation of movement, y = 0.81x + 0.25, r = 0.95, p < 0.001. CONCLUSION:We estimated the motion of abdominal artery due to respiration using the optical flow method in multiphase hepatic CT scans and the motion estimations were validated with the visualization of physicians. The quantitative analysis of respiration-related movement of abdominal artery could be used for motion correction in the measurement of contrast medium passing though abdominal artery in multiphase CT liver scans.