Publications by authors named "Hirka G"

Agmatine, 1-Amino-4-guanidinobutane, is a ubiquitous naturally occurring molecule present in low amounts in a wide variety of foodstuff. Clinical trials have demonstrated the safety of oral agmatine sulfate and have led to its development as an effective dietary ingredient for promoting resilient nerve functions. Although clearly required, the mutagenic and genotoxic effects of agmatine have not been previously reported.

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Xanthobacter sp. SoF1 (SoF1) is an autotrophic hydrogen-oxidizing bacteria that produces protein-rich biomass and has potential to be an alternative protein source that is more environmentally sustainable than animal and plant derived proteins. A protein-rich powder derived from SoF1 was the test material in a 90-day repeated-dose oral toxicity study to explore major toxic effects, demonstrate target organs, and provide an estimate of a no-observed-adverse-effect level (NOAEL).

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Interest in microalgae products for use in food is increasing, as demands for sustainable and cost-effective food choices grow due to the escalating global population and increase in climate-related struggles with agriculture. Toxicological assessments of some species of microalgae have been conducted, but there were little data available for the oral consumption of the red microalgae Porphyridium purpureum and no data on genotoxicity. This article articulates a genotoxicity assessment and a 90-day repeated dose oral toxicity study in rats performed according to OECD guidelines.

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Mulberry (genus Morus) leaves have long been used as a human food, especially in Asia, and animal feed. More recently, mulberry leaf extracts have been introduced as a convenient way to consume mulberry for non-nutritional functional effects. Reducose® 5% is an Morus alba leaf extract that has been highly purified and standardized to a content of 5 ± 0.

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Currently, there is much interest in the sales and study of consumable Cannabis sativa L. products that contain relatively high levels of cannabidiol (CBD) and low levels of Δ-9-tetrahydrocannabinol. While there are published safety evaluations for extracts containing low concentrations of CBD, toxicological assessments for those with higher concentrations are still scant in the public domain.

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There is a growing global interest in using peptides in the health industry for pharmaceuticals, cosmetics, and natural food products. Peptides contain two or more linked amino acids, whereas more than 50 amino acids are classified as polypeptides. Although there is a growing level of interest in the use of peptides in the health and wellness industry, there is a lack of literature pertaining to a specific tripeptide derived from arginine, alanine, and lysine (RAK) that is of interest for human dietary use.

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There is an economic interest, both for food security and for the non-meat-eating population, in the development of novel, sustainable sources of high-quality protein. The green algae Chlamydomonas reinhardtii has already been developed for this purpose, and the closely related species, Chlamydomonas debaryana, is a complementary source that also presents some additional advantages, such as reduced production cost. To determine whether C.

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Microorganisms have the potential to produce nutrient-rich products that can be consumed as food or feed. The protein-rich powder derived from heat treatment of the whole-cell biomass of polyhydroxybutyrate-deficient Cupriavidus necator, a metabolically versatile organism that uses elements found in the air, is an example of such a product. To assess the safety of the protein powder for use as a nutritional ingredient in human food, in accordance with internationally accepted standards, its genotoxic potential and repeated-dose oral toxicity were investigated.

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Veillonella atypica is a nonmotile, nonsporulating anaerobic bacteria commonly found in various human biofilms. V. atypica FB0054 was isolated from the gastrointestinal tract of marathon runners, who have increased amounts of this species after athletic events.

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As remdesivir, the first FDA-approved drug for SARS-CoV-2 infection, can be used only for hospitalized patients due to intravenous administration, there is an urgent need of effective oral antiviral formulations to be used at early stage of infection in an outpatient setting. The present paper reports on the comparative pharmacokinetics of the electrospun nanofiber remdesivir/sulfobutyl ether beta-cyclodextrin formulation after intravenous and buccal administration. It was postulated that oral transmucosal administration avoids remdesivir from metabolic transformation and intact remdesivir can be detected in plasma, but only the active metabolite GS-441524 could be experimentally detected at a significantly lower plasma level, than that provided by the intravenous route.

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Gold nanocrystals (AuNC) are gold nanoparticles (AuNP) relatively homogenous in size at 8-28 nm with clean surfaces and crystalline structures. There are concerns and a lack of consensus in the scientific literature and major regulatory bodies regarding not only the safety of nanoparticles when consumed by humans, but exactly how to determine their safety and whether evidence from a nanoparticle with one set of physiochemical properties extends to one with a different set. Additionally, there are few general long-term toxicity data on AuNP.

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Chlamydomonas reinhardtii is a nonpathogenic, nontoxigenic green algae used as a sustainable source of protein in foods. In order to mimic meat-like qualities, a strain rich in protoporphyrin IX (PPIX), an endogenous heme/chlorophyll precursor, was developed using an evolution and selection strategy, and investigations were carried out to evaluate the safety of the novel strain, C. reinhardtii (red), strain TAI114 (TAI114).

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Lithium orotate, the salt of lithium and orotic acid, has been marketed for decades as a supplemental source of lithium with few recorded adverse events. Nonetheless, there have been some concerns in the scientific literature regarding orotic acid, and pharmaceutical lithium salts are known to have a narrow therapeutic window, albeit, at lithium equivalent therapeutic doses 5.5-67 times greater than typically recommended for supplemental lithium orotate.

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Geranylgeraniol (GGOH) is an isoprenoid compound found in annatto seeds and an intermediate of the mevalonate pathway found within organisms serving various functions. Toxicological studies on its safety profile are not readily available. To assess the safety of GGOH, a molecularly distilled, food grade annatto oil, consisting of approximately 80% trans-GGOH, was subjected to a bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, and an in vivo mammalian micronucleus test in order to investigate its genotoxic potential and a 90-day repeated-dose oral toxicity study in rats in order to investigate its potential subchronic toxicity and identify any target organs.

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In this experimental work, sodium carboxymethyl beta-glucan (CMBG), a chemically altered beta-glucan, is evaluated for mutagenicity and sub-acute oral toxicity. Specifically, the tested material was CM-Glucan Nu, a food grade powder ≥90% CMBG derived from Saccharomyces cerevisiae. A bacterial reverse mutation test was performed and resulted in no mutagenicity.

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A novel 6-phytase (Phytase TSP, trade name OptiPhos® PLUS) with improved thermostability has been developed for use in animal feed. The safety of the new phytase was evaluated by testing for genotoxicity and subchronic toxicity. In and genotoxicity assays Phytase TSP concentrate was not mutagenic and did not induce biologically or statistically significant increases in the frequency of micronucleated polychromatic erythrocytes.

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Cyanate has been recognized as a uremic toxin that can adversely affect the clinical status of patients with chronic kidney disease. Besides, its toxicity has been under investigation in mammalian toxicology. If such studies are supplemented with toxicokinetic sampling and bioanalysis, additional information can be acquired about the systemic exposure.

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Humic substances are ubiquitous in soils and waters. These complex superstructures are derived from the decomposition of dead plant and animal matter and are vital to soil health. Their heterogenous composition is specific to their site of origin and is comprised of weakly bound aggregates of small organic compounds that can sequester minerals and make them available to plants.

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Monomethylsilanetriol (MMST), a silicon-containing compound, has been sold in dietary supplements. However, toxicological studies on its safety profile are not readily available. To assess the safety of MMST stabilized in acacia gum, a novel delivery form of MMST, in accordance with internationally accepted standards, the genotoxic potential and repeated-dose oral toxicity of Living Silica® Acacia Gum Stabilized Monomethylsilanetriol (formerly known as Orgono Acacia Gum Powder®), a food grade product consisting of 80 ± 10% acacia gum and 2.

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A battery of OECD- and GLP-compliant toxicological studies was performed to assess the safety of a highly purified germanium sesquioxide, an organic form of the naturally occurring, nonessential trace element germanium. Germanium dioxide and germanium lactate citrate (inorganic germaniums) have been shown to induce renal toxicity, whereas germanium sesquioxide (an organic germanium) has been shown to have a more favorable safety profile. However, past toxicity studies on germanium sesquioxide compounds have not clearly stated the purity of the tested compounds.

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Methylliberine (CAS 51168-26-4), a methoxiuric acid, is a caffeine metabolite present at low levels in various plants; however, very little has been published regarding this compound and we could find no toxicological data in the public domain. Therefore, we undertook the toxicological investigation of a pure, synthetic form of methylliberine in order to evaluate its potential health hazards as a food ingredient. A (1) bacterial reverse mutation test, (2) in vitro mammalian chromosomal aberration test, (3) in vivo mammalian micronucleus test, and (4) 90-day repeated-dose oral toxicity study in rats with a 28-day recovery period were conducted.

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A battery of OECD- and GLP-compliant toxicological studies was performed on mango leaf extract () containing 60% mangiferin (MLE). No evidence of genotoxicity was found in a bacterial reverse mutation test (Ames). While evidence of clastogenic activity was noted in an in vitro chromosomal aberration test, an in vivo mammalian micronucleus test showed no findings up to the limit dose (2000 mg/kg bw).

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Colostrum has been consumed safely for many years as a food collected directly from cows. More recently, an ultrafiltrated bovine colostrum product has been developed; however, its safety in toxicology studies has not been extensively evaluated. To assess the safety of bovine colostrum ultrafiltrate, in accordance with internationally accepted standards, the genotoxic potential was investigated in a bacterial reverse mutation test, an in vitro chromosomal aberration test, and an in vivo mammalian micronucleus test.

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A battery of toxicological studies was conducted to aid in the safety assessment of an ethanolic extract of Ageratum conyzoides for use as an ingredient in food. In accordance with internationally accepted standards, a bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, an in vivo mammalian micronucleus test, and a 90-day repeated-dose oral toxicity study in rats were performed. In the first three applied test systems, no evidence of mutagenicity, clastogenicity or genotoxicity was revealed.

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