Physiological responses of Pterocladiella capillacea (Rhodophyta, Gelidiales) under two light intensities

Abstract

Macroalgae must be able to survive in conditions of different light intensities with no damage to their physiological performance or vital processes. Irradiance can stimulate the biosynthesis of certain photoprotective compounds of biotechnological interest, such as pigments and proteins. Pterocladiella capillacea is a shade-grown alga, which play a role key in the balance of marine ecosystems. In addition, it is considered one of the best sources of bacteriological agar and agarose with a wide pharmacological potential. In order to evaluate the photosensitivity in P. capillacea under 60 (control) and moderate light intensity of 300 μmol(photon) m-2 s-1 , photosynthetic performance and chemical composition were assessed. P. capillacea showed photosensitivity without evidence of photodamage. The results indicate the possibility to increase a growth rate and probably infer productivity in long-term cultivation by stimulation at moderate light intensity. Increasing photosynthetic pigment and protein contents were also observed under medium light, an interesting result for functional ingredient approaches.

Sargassum stenophyllum (Fucales, Ochrophyta) responses to temperature short-term exposure: photosynthesis and chemical composition

“…Total soluble proteins, photosynthetic pigments and UV-absorbing spectrum -The extraction of soluble proteins was performed from 70 mg of fresh weight (FW) samples, following the method described by Harb et al (2018). The material was ground in liquid nitrogen and extracted with 1 mL of cold sodium phosphate buffer (50 mM, pH 5.5) and then centrifuged at 12.000 rpm for 15 min at 4 °C (buffered extract).…”

Concise review of genus Lessonia Bory

“…Lessonia flavicans, L. nigrescens, and L. trabeculata extracts provide a mixture of fucans and alginic acid that may be applied in agriculture as a pesticide against harmful fungi in wheat and tobacco (Percival et al 1983;Chandía et al 2004Chandía et al , 2005Matsuhiro and Zambrano 2004). Fucoidan and alginic acid compositions are altered depending on the environmental conditions to which the seaweeds are exposed (water motion, light and temperature) (Martins et al 2011;Valiente and Mogollón 2013;Harb et al 2018;Urrea-Victoria et al 2020). For example, Lessonia from exposed sites produces a high content of polysaccharides compared to sheltered sites, in addition to different gel quality throughout the year (Chandía et al 2004(Chandía et al , 2005Valiente and Mogollón 2013;Leal et al 2018;Zou et al 2019).…”

Efeito do estresse térmico sobre respostas fisiológicas, composição química e potencial antioxidante de Sargassum stenophyllum (Fucales, Ochrophyta) e Pyropia spiralis (Bangiales, Rhodophyta)

“…The extraction of soluble proteins was performed from 70 mg of fresh weight (FW) samples, following the method described by Harb et al (2018). The material was ground in liquid nitrogen and extracted with 1 mL of cold sodium phosphate buffer (50 mM, pH 5.5), and then centrifuged at 12,000 rpm for 15 min at 4 °C (buffered extract).…”

“…O teor de pigmentos fotossintetizantes (ficobiliproteínas, clorofila a e carotenoides) e de proteínas solúveis foram analisados a partir de amostras de 70 mg de massa fresca (MF), seguindo o método descrito em Harb et al (2018).…”

“…Com os extratos metanólicos foi quantificada a clorofila a mediante a fórmula descrita em Harb et al (2018), e os carotenoides segundo Lichtenthaler & Buschmann (2001); com as seguintes fórmulas: Clorofila a (µg g -1 MF) = (12,61 x A664) e Carotenoides (µg g -1 MF) = {1000 x [A470 -1,63 x Concentração de clorofila a]} / 221; sendo A a absorbância no respectivo comprimento de onda.…”