An Attempt to Replace Pure Citric Acid with Natural Lemon Juice during Potato Starch Esterification.

The application of chemical operations in food processing, in which pure chemical compounds are used to modify food ingredients, often raises social concerns. One of the most frequently modified dietary substances is starch, e.g., E1401-E1404, E1412-E1414, E1420, E1422, E1440, E1442, and E1450-E1452. An alternative solution to chemical treatments seems to be the use of raw materials naturally containing substrates applied for starch modification. Heating starch with a lemon juice concentrate can be considered a novel and effective method for producing starch citrate, which is part of the so-called "green chemistry". The modified preparations obtained as a result of potato starch esterification with natural lemon juice had a comparable degree of esterification to that of the esters produced with pure citric acid. In addition, the use of the juice doubled their resistance to amylolytic enzymes compared to the preparations made with pure acid. Replacing citric acid with lemon juice can facilitate the esterification process, and the analyzed properties of both types of modified preparations indicate that starch esters produced with pure citric acid can be successfully replaced by those produced using natural lemon juice, which may increase the social acceptance of these modified preparations.

Innovative Polymer Composites with Natural Fillers Produced by Additive Manufacturing (3D Printing)-A Literature Review.

In recent years, plastics recycling has become one of the leading environmental and waste management issues. Along with the main advantage of plastics, which is undoubtedly their long life, the problem of managing their waste has arisen. Recycling is recognised as the preferred option for waste management, with the aim of reusing them to create new products using 3D printing. Additive manufacturing (AM) is an emerging and evolving rapid tooling technology. With 3D printing, it is possible to achieve lightweight structures with high dimensional accuracy and reduce manufacturing costs for non-standard geometries. Currently, 3D printing research is moving towards the production of materials not only of pure polymers but also their composites. Bioplastics, especially those that are biodegradable and compostable, have emerged as an alternative for human development. This article provides a brief overview of the possibilities of using thermoplastic waste materials through the application of 3D printing, creating innovative materials from recycled and naturally derived materials, i.e., biomass (natural reinforcing fibres) in 3D printing. The materials produced from them are ecological, widely available and cost-effective. Research activities related to the production of bio-based materials have gradually increased over the last two decades, with the aim of reducing environmental problems. This article summarises the efforts made by researchers to discover new innovative materials for 3D printing.

Physicochemical Properties and Digestion Resistance of Acetylated Starch Obtained from Annealed Starch.

One of the examples of physical starch modifications is the retention of a starch suspension in water having a temperature slightly lower than the pasting temperature (annealing). The aim of this study was to investigate the effect of the annealing process performed at various temperatures as the first stage of starch modification. The annealed starch preparations were then esterified using acetic acid anhydride. Finally, the annealed and acetylated starch preparations were determined for their properties. The annealing of starch before acetylation triggered changes in the properties of the modified preparations. It contributed to a higher degree of starch substitution with acetic acid residues and to the increased swelling power of starch. Both these properties were also affected by the annealing temperature. The highest resistance to amylolysis was found in the case of the starch preparation annealed at 53.5 °C and acetylated. The double modification involving annealing and acetylation processes increased the onset and end pasting temperatures compared to the acetylation alone. Similar observations were made for the consistency coefficient and yield point.

Effect of the Esterification of Starch with a Mixture of Carboxylic Acids from Yarrowia lipolitica Fermentation Broth on Its Selected Properties.

Potato starch was esterified with carboxylic acids contained in the fermentation broth from Yarrowia lipolitica yeast production. Various acid concentrations and various roasting temperatures were used to determine effects of process conditions on ester properties, including the number of acid residues attached to starch chains, starch susceptibility to amylolysis, and thermal characteristics of starch phase transitions. Study results demonstrated the effect of both the composition and the dose of the fermentation broth and of roasting temperature of starch on the number of acid residues attached to starch chains. Citric acid was more susceptible to esterification with starch (DS = 5.65%) compared to the α-ketoglutaric acid (DS = 0.12%). In the case of the latter, a higher degree of substitution was determined in the esters produced at higher roasting temperatures. The lowest digestibility (RS = 20%) was demonstrated for the starch esters with the highest degree of substitution with citric acid, whereas all starch esters showed decreased values of the thermal characteristics of pasting.

Organic Acids of the Microbiological Post-Culture Medium as Substrates to be Used for Starch Modification.

This study aimed to identify the feasibility of producing highly-substituted starch esters via thermal modification of starch using a post-culture medium of Yarrowia lipolitica yeast. This manuscript describes a successful attempt at potato starch modification with a post-culture medium of Yarrowia lipolitica yeast with different concentrations of organic acids. Starch preparations produced by roasting (130 °C) and these produced by starch reaction with a synthetic acid mixture were compared in terms of the types and number of acid residues esterified with starch. The effectiveness of starch esterification was found to depend on medium composition and to be higher upon the use of a synthetic acid mixture. In addition, a higher reactivity with starch was demonstrated for citric acid than for α-ketoglutaric acid. The highly-substituted starch esters formed as a result of potato starch modification with post-culture medium were characterized by decreased values of thermal parameters of pasting characteristics, determined with a differential scanning calorimeter (DSC), and by compromised resistance to amylolysis. The intensity of these changes increased along with an increasing total percentage of starch ester substitution.

[Fixation in patients with anisometropic amblyopia without strabismus]. / Fiksacja u pacjentów z niedowidzeniem i róznowzrocznoscia bez zeza.

PURPOSE: To determine the type of fixation in patients with anisometropic amblyopia without strabismus and find correlation between amount of anisometropia and eccentricity of fixation. MATERIAL AND METHODS: 100 patients with anisometropic amblyopia without strabismus were examined. The following data was obtained: visual acuity, type of fixation, refraction error after cycloplegia. Amount of anisometropia was calculated as the difference of spherical equivalents. RESULTS: Only 44% of patients demonstrated central fixation. The amount of amblyopia corresponded to eccentricity of fixation. For most cases (anisometropia up to 6D of SE) the amount of anisometropia did not correlate with eccentricity of fixation. CONCLUSIONS: Simply difference of refraction must not be the only factor affecting development of anisometropic amblyopia.

[Microbiological evaluation of conjunctival sac in Sjögren syndrome patients]. / Ocena mikrobiologiczna zawartosci worka spojówkowego u chorych z zespolem Sjögrena.

PURPOSE: To evaluate bacterial flora of conjunctival sac in patients with Sjogren syndrome and compare it with the flora of healthy individuals. MATERIAL AND METHODS: Bacteriological test was performed on the swabs from the conjunctival sac of 15 patients with primary Sjögren syndrome (PS), 15 patients with secondary Sjögren syndrome (SS) and 30 healthy individuals, chosen at random. RESULTS: Most of the swabs, in every group, were aseptic. The bacteria found relatively often was Staphylococcus epidermidis or described as the Staphylococcus sp. coagulasonegative. Bacterias: Staphylococcus aureus, Corynebacterium or Enterobacteriaceae were found rarely. CONCLUSIONS: There is no significant difference between bacterial flora of conjunctival sac of patients with PS and SS, when compared to healthy individuals.

[Vascular flow in patients with retinal detachment in the color Doppler's ultrasonography]. / Przeplyw naczyniowy u chorych z odwarstwieniem siatkówki w kolorowej ultrasonografii dopplerowskiej.

UNLABELLED: For many years now Doppler's ultrasonography has been broadly applied in ophthalmology. Recently it has been communicated, that there is a possibility of assessing the disorders of retinal circulation in the process of retinal detachment. PURPOSE: Our research had to establish, whether after the scleral buckling treatments executed due to the retinal detachment, there is a change in the blood flow in the vessels of the eyeballs. MATERIAL AND METHODS: The observations were conducted in 30 eyes of 15 people, who were diagnosed with opening-related retinal detachment. The colour Doppler's ultrasonography was performed by using ATL Ultramark 9HDI apparatus with a linear sound of the frequency range from 7.5 to 10 MHz. The anatomic structures of the eye socket in the transverse and arrow plane were assessed. The flow spectrum was measured according to the PD method (pulsating Doppler) in the central artery of the retina at the distance of approximately 2-4 mm from the optic disc and in the ophthalmic artery. The analysis of the spectrum allowed one to determine the values of the pulsation indexes-PI, and resistance indexes-RI, in the ophthalmic artery and in the central artery of the retina of the healthy eye, and of the eye with detached retina 2-3 days before and in 5-7 days after the operative procedure. RESULTS: After radial and circumferential buckling treatments, the conducted research found no increased resistance of the flow in the arteries, namely: the central artery of the retina and the ophthalmic artery. The condition for the maintenance of the correct parameters of the blood flow was the intraocular pressure. At the same time, in the eyes with detached retina, the decrease in the resistance of the flow in the ophthalmic artery was observed, which was being brought back to normal after the operative treatment.