Phenolic and antioxidant capacity retention of potato peel waste as a function of cultivar, pretreatment and drying procedure

Drying procedures employed for potato peels (both raw and boiled) may adversely affect the useful bioactivecomponents present in them. This study envisaged the identification of a feasible drying procedure for handlingbulk potato peel waste for maximising the retention of phytochemicals in the peel powder. The total phenols (TP), flavonoids (TF) and antioxidant capacity (TAC) were assessed in peels of three commercial and one newly developed anthocyanin rich Indian potato cultivars in response to boiling pretreatment and varying drying procedures. Microwave drying (600W) was best in terms of drying rate for both raw and boiled peels. It yielded the greatest amount of TP and TF in the dried raw peel, irrespective of cultivar. Dried raw peels of an thocyanin rich Kufri Neelkanth cultivar exhibited maximum TAC. Retention of TF, metal scavenging activity and reducing power followed almost a similar pattern as TP irrespective of cultivar, pretreatment and drying procedure. Our study shows that potato peel from Kufri Neelkanth (raw) and Kufri Frysona (both raw and boiled) are best source of phenolics and flavonoids and can serve as a suitable matrix for extraction of bioactive compounds which holds promise for use in the food industry

Corneal avascularity is due to soluble VEGF receptor-1

Corneal avascularity-the absence of blood vessels in the cornea-is required for optical clarity and optimal vision, and has led to the cornea being widely used for validating pro- and anti-angiogenic therapeutic strategies for many disorders. But the molecular underpinnings of the avascular phenotype have until now remained obscure and are all the more remarkable given the presence in the cornea of vascular endothelial growth factor (VEGF)-A, a potent stimulator of angiogenesis, and the proximity of the cornea to vascularized tissues. Here we show that the cornea expresses soluble VEGF receptor-1 (sVEGFR-1; also known as sflt-1) and that suppression of this endogenous VEGF-A trap by neutralizing antibodies, RNA interference or Cre-lox-mediated gene disruption abolishes corneal avascularity in mice. The spontaneously vascularized corneas of corn1 and Pax6+/- mice and Pax6+/- patients with aniridia are deficient in sflt-1, and recombinant sflt-1 administration restores corneal avascularity in corn1 and Pax6+/- mice. Manatees, the only known creatures uniformly to have vascularized corneas, do not express sflt-1, whereas the avascular corneas of dugongs, also members of the order Sirenia, elephants, the closest extant terrestrial phylogenetic relatives of manatees, and other marine mammals (dolphins and whales) contain sflt-1, indicating that it has a crucial, evolutionarily conserved role. The recognition that sflt-1 is essential for preserving the avascular ambit of the cornea can rationally guide its use as a platform for angiogenic modulators, supports its use in treating neovascular diseases, and might provide insight into the immunological privilege of the cornea

The lithium intercalation process in the low-voltage lithium battery anode Li1+xV1−xO2

Lithium can be reversibly intercalated into layered Li1+xV1−xO2 (LiCoO2 structure) at ∼0.1 V, but only if x>0. The low voltage combined with a higher density than graphite results in a higher theoretical volumetric energy density; important for future applications in portable electronics and electric vehicles. Here we investigate the crucial question, why Li cannot intercalate into LiVO2 but Li-rich compositions switch on intercalation at an unprecedented low voltage for an oxide? We show that Li+ intercalated into tetrahedral sites are energetically more stable for Li-rich compositions, as they share a face with Li+ on the V site in the transition metal layers. Li incorporation triggers shearing of the oxide layers from cubic to hexagonal packing because the Li2VO2 structure can accommodate two Li per formula unit in tetrahedral sites without face sharing. Such understanding is important for the future design and optimization of low-voltage intercalation anodes for lithium batteries

Pathogenesis of Streptococcus urinary tract infection depends on bacterial strain and β-hemolysin/cytolysin that mediates cytotoxicity, cytokine synthesis, inflammation and virulence

Streptococcus agalactiae can cause urinary tract infection (UTI) including cystitis and asymptomatic bacteriuria (ABU). The early host-pathogen interactions that occur during S. agalactiae UTI and subsequent mechanisms of disease pathogenesis are poorly defined. Here, we define the early interactions between human bladder urothelial cells, monocyte-derived macrophages, and mouse bladder using uropathogenic S. agalactiae (UPSA) 807 and ABU-causing S. agalactiae (ABSA) 834 strains. UPSA 807 adhered, invaded and killed bladder urothelial cells more efficiently compared to ABSA 834 via mechanisms including low-level caspase-3 activation, and cytolysis, according to lactate dehydrogenase release measures and cell viability. Severe UPSA 807-induced cytotoxicity was mediated entirely by the bacterial β-hemolysin/cytolysin (β-H/C) because an β-H/C-deficient UPSA 807 isogenic mutant, UPSA 807ΔcylE, was not cytotoxic in vitro; the mutant was also significantly attenuated for colonization in the bladder in vivo. Analysis of infection-induced cytokines, including IL-8, IL-1β, IL-6 and TNF-α in vitro and in vivo revealed that cytokine and chemokine responses were dependent on expression of β-H/C that also elicited severe bladder neutrophilia. Thus, virulence of UPSA 807 encompasses adhesion to, invasion of and killing of bladder cells, pro-inflammatory cytokine/ chemokine responses that elicit neutrophil infiltration, and β-H/C-mediated subversion of innate immune-mediated bacterial clearance from the bladder.Full Tex