Assessment of growth and fermentation of some yeasts on soybean residue hydrolysate

This study explored the growth and fermentation capabilities of four distinct yeast strains, including Saccharomyces cerevisiae var. boulardii CNCM I-745, S. cerevisiae 7012, S. cerevisiae 7028, and S. cerevisiae var. diastaticus BE-134, with the aim of identifying the most suitable strain for the production of a fermented beverage from soybean residue hydrolysate (SRH). The results were as follows: S. cerevisiae 7012 exhibited the most efficient fermentation, with residual sugar content of 2.16 g/100 ml, an ethanol concentration of 1.39% v/v, and a favourable aroma, receiving a sensory score of 4.3/5 points. Within this sensory profile, the aromatic compound 2-phenylethanol was found to be the predominant component. Additionally, S. cerevisiae var. boulardii CNCM I-745 demonstrated superior biomass production ability, achieving a cell density of 7.71 log CFU/ml after 48 hours of fermentation solution also showed the highest antioxidant activity, equivalent to 1.63 mg of ascorbic acid per 100 ml. Consequently, these two yeast strains were selected for combined use in fermentation to leverage the probiotic characteristics of S. cerevisiae var. boulardii CNCM I-745 and the flavouring capacity of S. cerevisiae 7012 in creating fermented beverages from SRH

On the performance analysis of a DCSK system under the pulse jamming environment.

This paper considers the DCSK system under jamming environment. We consider both fast and slow switching pulse jamming (PJ). We derive approximations of the system bit error rates (BERs) in analytic expressions containing only well-known special functions, from which we show that for both jamming cases increasing the spreading factor can enhance the BER. In addition, we reveal that under the fast switching PJ, the BER does not depend on the jamming duty cycle ρ when ρ ≤ 0.5, however when ρ > 0.5, increasing its value degrades the BER. Moreover, we find out that under the slow switching PJ, increasing ρ may either enhance or degrade the BER

Selection of extraction conditions of phenolic compounds from rambutan (Nephelium lappaceum L.) peel

The objectives of this study focused on optimizing extraction conditions (i.e. type of solvent (methanol, ethanol, and water) and their concentration, temperature, time, and the effect of ultrasound-assisted extraction (UAE)) for extracting phenolic compounds of rambutan fruit peel. Furthermore, a procedure to prepare crude phenolic powder from rambutan peel was suggested. Total phenolic content and antioxidant properties of rambutan peel extracts were examined using spectrophotometric methods. Solid phase extraction and high-performance liquid chromatography were used for identifying phenolic compositions in rambutan peel extracts. Methanol 80% had significant effects to obtain higher extraction yields of phenolic compounds. UAE significantly affected the yield of phenolics of rambutan peel with an increase in phenolic content of 15% compared to methanolic extraction (without ultrasound application). Phenolic compounds such as geraniin, corilagin, rutin, ellagic acid, and quercetin were predominant in rambutan peel extracts. An extraction procedure was summed up to obtain 55-64 g of lyophilized powder from 1 kg of fresh rambutan peel. The total phenolic content in this crude phenolic powder was 250-300 mg GAE/g. Its antioxidant activity (at 100 mu g GAE/mL) was much higher than those of tert-butylhydroquinone, L-ascorbic acid, alpha-tocopherol, and ethylenediaminetetraacetic acid (at 100 mu g/mL (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved