Oil encapsulation by spray drying and fluidised bed agglomeration

Many active components (anti-oxidants, aromas) are lipophilic substances, available in liquid form and have to be protected from the environment. Encapsulation of oil drops into a solid matrix is regarded as an efficient protection method and a means of formulating liquid compounds in a solid dosed form.The aim of this study is to investigate the feasibility of encapsulation of a vegetable oil (ISIO4 (R), 5% w/w dry matter) used as a model into a mixture of maltodextrin and acacia guru. Encapsulation was completed in three stages, i.e. emulsification, spray drying and fluid bed agglomeration. Optimal operating conditions for spray drying and agglomeration were identified. Powders were characterized before and after agglomeration in terms of oil content and protection (dispersion into the matrix, surface oil content, oxidation) and powder handling properties (flowability, wettability, friability).The proposed encapsulation method provided powders where oil droplets were well dispersed and protected (oil droplets diameter lower than 1 mu m in reconstituted emulsions, less than 2% of the total oil content at the particle surface, oil oxidation lowered compared to unprotected oil). Agglomeration did not change oil encapsulation properties of the spray-dried powder but considerably improved its wettability

Encapsulation of oil in powder using spray drying and fluidised bed agglomeration

Many food active molecules such as antioxidants and aromas, exist in an oil form which may be easily oxidised. They are often prepared as a dosed, free-flowing powder, for storage protection and controlled release purposes. Oil encapsulation in powder was tested using a vegetable oil (VO) chosen as a model (5% w of dry matter) with a support of maltodextrin (MD) and acacia gum (AG) (ratio 3/2 w/w). Spray drying of a formulated aqueous emulsion (VO/MD/AG) led to small particles ( < 50 mu M). Further, their size was increased (150 mu m) by agglomeration in an air fluidised bed with spraying of water. Direct agglomeration of maltodextrin with an aqueous emulsion (VO/AG) represents a good process alternative, leading to particles of 200 pm. The two agglomerated powders consist of 5% of oil well dispersed in the support (MD/AG), with less than 0.5% on the particles surface. The protection against oil oxidation is good in comparison with unencapsulated oil. Also the agglomerated powders have suitable properties of flowability and wettability

Efficacy of Food Proteins as Carriers for Flavonoids

Enrichment of flavonoids in food is often limited by their off-tastes, which might be counteracted by the use of food proteins as carriers of flavonoids. Various milk proteins, egg proteins, and gelatin hydrolysates were compared for their binding characteristics to two flavan-3-ols. Among the proteins tested for their affinities toward epigallocatechin gallate (EGCG), β-casein and gelatin hydrolysates, in particular fish gelatin, were found to be the most promising carriers with an affinity on the order of 10⁴ M^–1. A flexible open structure of proteins, as present in random coil proteins, was found to be important. The saturation of binding observed at high flavonoid/protein ratios was used to estimate the maximal binding capacity of each protein. To reach a daily intake of EGCG that has been associated with positive health effects, only 519 mg of gelatin B and 787 mg of β-casein were required to complex EGCG on the basis of their maximal binding capacity. When the absence of turbidity is taken into account, β-casein prevails as carrier. Three selected proteins were further investigated for their binding potential of representative flavonoids differing in their C-ring structure. An increase in hydrophobicity of flavonoids was related to a higher affinity for proteins, and the presence of a gallic acid ester on the C-ring showed an overall higher affinity

Preclinical efficacy of MEK inhibition in Nras-mutant AML.

Oncogenic NRAS mutations are highly prevalent in acute myeloid leukemia (AML). Genetic analysis supports the hypothesis that NRAS mutations cooperate with antecedent molecular lesions in leukemogenesis, but have limited independent prognostic significance. Using short hairpin RNA-mediated knockdown in human cell lines and primary mouse leukemias, we show that AML cells with NRAS/Nras mutations are dependent on continued oncogene expression in vitro and in vivo. Using the Mx1-Cre transgene to inactivate a conditional mutant Nras allele, we analyzed hematopoiesis and hematopoietic stem and progenitor cells (HSPCs) under normal and stressed conditions and found that HSPCs lacking Nras expression are functionally equivalent to normal HSPCs in the adult mouse. Treating recipient mice transplanted with primary Nras(G12D) AMLs with 2 potent allosteric mitogen-activated protein kinase kinase (MEK) inhibitors (PD0325901 or trametinib/GlaxoSmithKline 1120212) significantly prolonged survival and reduced proliferation but did not induce apoptosis, promote differentiation, or drive clonal evolution. The phosphatidylinositol 3-kinase inhibitor GDC-0941 was ineffective as a single agent and did not augment the activity of PD0325901. All mice ultimately succumbed to progressive leukemia. Together, these data validate oncogenic N-Ras signaling as a therapeutic target in AML and support testing combination regimens that include MEK inhibitors