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Rhodophyta represents the largest seaweed phylum including a wide variety of species, such as Chondrus crispus Stackhouse, with benefits for consumers health due to their nutritional value and bioactive compounds. This work aimed to optimize the extraction of compounds from C. crispus using a three-step optimization process. The first step consisted in pigment extraction using ultrasound-assisted extraction; the performance of an ultrasonic probe (20 kHz, 750 W) and a bath (40 kHz, 120 W) for 20 or 40 min was compared. The second step corresponded to protein extraction and the third step was the carrageenan formation. Step 1 extracts contained two carotenoids (fucoxanthin and lutein), 5 chlorophyll- a derivatives and pheophythin- a , phenolic compounds and revealed moderate antiradical activity against DPPH•, ABTS•+ and O 2 •-, but no activity against •NO and cholinesterases. Proteins and carrageenan's yields were between 3.6 and 41 g/100 g and 29.7–36.1 g/100 g, respectively. Considering all the performed analyses, the use of ultrasonic bath (40 kHz, 120 W) for 40 min is efficient to extract valuable compounds from C. crispus , which is advantageous from an economic point of view and therefore more attractive for industrial purposes. The obtained extracts may find possible future application in human diet or as additives for pharmaceutic and cosmetic industry. • C. crispus bioactive compounds were extracted by a three-step optimization process. • Pigment extract revealed moderate antiradical activity against DPPH.•, ABTS•+ and O 2 •- • Pigment extract had no activity against.•NO and cholinesterases • Proteins and carrageenans yields were between 3.6% - 41% and 29.7%–36.1%. • The ultrasonic bath (40 kHz, 120 W) for 40 min was the preferable approach. [ABSTRACT FROM AUTHOR]

Brewer's spent yeast (BSY) is the second major by-product from brewing and is recognized as a promising source of potentially bioactive ingredients, namely the cell-wall β-glucans. However, to make the process of β-glucans’ separation from BSY profitable, new applications for the inner cell content are required. Mechanical disruption of BSY cell wall was performed to separate the β-glucans rich fraction and obtain an extract from intracellular content, rich in native proteins and enzymes, which was submitted to further autolysis. This short communication describes the optimization of BSY extract autolysis, by Response surface methodology (RSM), to produce a BSY autolysate comprising antioxidant and ACE-inhibitory activities. RSM enabled the prediction of optimum autolysis conditions. Autolysis of BSY inner cell content at 36.0 °C, 6.0 h gave a TPC of 385 μM GAE/mL, a FRAP value of 374 μM TE/mL and an IC 50 value of 379 μg/mL. These experimental results were in agreement with the RSM predicted values. The combination of ACE-I and antioxidant activities in one autolysate can be very useful as functional ingredient for food industry and complement the extractive process of β-glucans from cell wall. [ABSTRACT FROM AUTHOR]

Spent yeast is the second major by-product from brewing. Mechanical disruption of yeast cell wall can be used to obtain β-glucan rich ingredients and separate inner yeast content, both with potential applications as food and nutraceutical ingredients. In this work, the nutritional composition, including minerals and B-complex vitamins, together with the antioxidant activity and phenolic compounds profile of yeast extract, prepared by mechanic disruption of brewer’s spent yeast and removal of yeast cell wall, was investigated. The lyophilised yeast extract presented 64% of proteins with high proportion of essential amino acids and 4% of RNA; macrominerals (Na, K, Ca, Mg), trace elements such as Zn (11.9 mg/100 g dw), Fe (1.76 mg/100 g dw), and Mn (0.564 mg/100 g dw), and vitamins B3 (77.2 mg/100 mg dw), B6 (55.1 mg/100 g dw) and B9 (3.01 mg/100 g dw). Two phenolic compounds were quantified as free forms, gallic acid and (±) catechin, whereas other bounded phenolic compounds were also quantified. The nutrients content, antioxidant properties and phenolic composition of the lyophilised brewer’s spent yeast extract indicates that it can be an interesting food or nutraceutical ingredient. Thus, its recovery will be beneficial in terms of sustainability and environmental impact. [ABSTRACT FROM AUTHOR]