Chain Extension of Poly(Lactic Acid) (PLA)-Based Blends and Composites Containing Bran with Biobased Compounds for Controlling Their Processability and Recyclability.

The present work focused on the research, design, and study of innovative chain extender systems of renewable origin for PLA-based biocomposites, reinforced with wheat bran as filler. The majority of employed chain extender compounds belongs to fossil world, affecting the biodegradability property which characterizes biopolymers. The aim of this work was thus to find promising biobased and sustainable alternatives to provide the same enhancements. According to this objective, epoxidized soybean oil (ESO) was chosen as principal component of the chain extender systems, together with a dicarboxylic acid, malic acid (MA), or succinic acid (SA). The reactivity of the modifier systems was previously studied through thermogravimetric analysis (TGA) and IR spectroscopy, to hypothesize the reaction mechanism in bran-filled blends. Hence, small-scale extrusion was carried out to investigate the effects of ESO/MA and ESO/SA on formulations of different composition (both pure PLA blends and composites). The variation of melt fluidity parameters was analyzed to define the optimized concentration of modifier systems. A comparison between the effects on blends of designed biobased systems and the action of fossil-based Joncryl was performed, to understand if the developed green solutions could represent competitive and efficient substitutes. The modified composites were characterized in terms of mechanical tests, degradation and thermal studies (TGA and DSC), and morphological analysis (SEM), to figure out their main features and to understand their potential in possible industrial applications.

Lacticaseibacillus paracasei DG enhances the lactoferrin anti-SARS-CoV-2 response in Caco-2 cells.

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing the ongoing global pandemic of coronavirus disease 2019 (COVID-19), which primarily manifests with respiratory distress and may also lead to symptoms associated with the gastrointestinal tract. Probiotics are living microorganisms that have been shown to confer immune benefits. In this study, we investigated the immunomodulatory effects and anti-SARS-CoV-2 activity of three different Lacticaseibacillus probiotic strains, either alone or in combination with lactoferrin, using the intestinal epithelial Caco-2 cell line. Our results revealed that the Lacticaseibacillus paracasei DG strain significantly induced the expression of genes involved in protective antiviral immunity and prevented the expression of proinflammatory genes triggered by SARS-CoV-2 infection. Moreover, L. paracasei DG significantly inhibited SARS-CoV-2 infection in vitro. L. paracasei DG also positively affected the antiviral immune activity of lactoferrin and significantly augmented its anti-SARS-CoV-2 activity in Caco-2 intestinal epithelial cells. Overall, our work shows that the probiotic strain L. paracasei DG is a promising candidate that exhibits prophylactic potential against SARS-CoV-2 infection.

Protective Effects of Lactoferrin against SARS-CoV-2 Infection In Vitro.

SARS-CoV-2 is a newly emerging virus that currently lacks curative treatments. Lactoferrin (LF) is a naturally occurring non-toxic glycoprotein with broad-spectrum antiviral, immunomodulatory and anti-inflammatory effects. In this study, we assessed the potential of LF in the prevention of SARS-CoV-2 infection in vitro. Antiviral immune response gene expression was analyzed by qRT-PCR in uninfected Caco-2 intestinal epithelial cells treated with LF. An infection assay for SARS-CoV-2 was performed in Caco-2 cells treated or not with LF. SARS-CoV-2 titer was determined by qRT-PCR, plaque assay and immunostaining. Inflammatory and anti-inflammatory cytokine production was determined by qRT-PCR. LF significantly induced the expression of IFNA1, IFNB1, TLR3, TLR7, IRF3, IRF7 and MAVS genes. Furthermore, LF partially inhibited SARS-CoV-2 infection and replication in Caco-2 intestinal epithelial cells. Our in vitro data support LF as an immune modulator of the antiviral immune response with moderate effects against SARS-CoV-2 infection.