pulsed electric field assisted juice extraction of frozen thawed blueberries

Pulsed electric field is an efficient method for cell membrane permeabilization of food tissues with most research being done on fresh plant cells. Freeze/thawing is also known to be capable of cell membrane permeabilization. In this work, frozen/thawed European blueberry (Vaccinium myrtillus L.) fruits were treated with pulsed electric field in order to further enhance the cell membrane permeabilization and, hence, the quality of blueberry juice during the subsequent pressing process. Blueberries tissues were exposed to 20 μs monopolar square wave pulses of different electric field strength (E = 1–3–5 kV cm-1) and total specific energy input (WT = 1–5–10 kJ kg -1), with their permeabilization being characterized by electrical impedance measurements and cell disintegration index (Zp). The juice, obtained after pressing (1.32 bar), was characterized for total polyphenols, anthocyanins content and antioxidant activity. The cell disintegration index (Zp) significantly (p < 0.05) increased from 0.2 up to 0.6 with increasing pulsed electric field treatment intensity (E and WT). As a results, in comparison with control, pulsed electric field treatment induced a slightly higher release of polyphenols (up to +8.0%) and anthocyanins (up to +8.3%), thus improving the antioxidant activity of the juice (up to +16.7%). In conclusion, frozen/thawed blueberries could be pulsed electric field treated in order to further increase juice quality

Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

Background: We previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15–20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in ~ 80% of cases. Methods: We report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded. Results: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5–528.7, P = 1.1 × 10−4) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR = 3.70[95%CI 1.3–8.2], P = 2.1 × 10−4). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR = 19.65[95%CI 2.1–2635.4], P = 3.4 × 10−3), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR = 4.40[9%CI 2.3–8.4], P = 7.7 × 10−8). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD] = 43.3 [20.3] years) than the other patients (56.0 [17.3] years; P = 1.68 × 10−5). Conclusions: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60&nbsp;years old