Dasatinib (DAS), a potent anticancer drug, has been subjected to formulation enhancements due to challenges such as significant first-pass metabolism, poor absorption, and limited oral ...bioavailability. To improve its release profile, DAS was embedded in a matrix of the hydrophilic polymer polyvinylpyrrolidone (PVP). Drug amorphization was induced in a planetary ball mill by solvent-free co-grinding, facilitating mechanochemical activation. This process resulted in the formation of amorphous solid dispersions (ASDs). The ASD capsules exhibited a notable enhancement in the release rate of DAS compared to capsules containing the initial drug. Given that anticancer drugs often undergo limited metabolism in the body with unchanged excretion, the ecotoxicological effect of the native form of DAS was investigated as well, considering its potential accumulation in the environment. The highest ecotoxicological effect was observed on the bacteria
, while other test organisms (bacteria
, microalgae
sp., and duckweed
) exhibited negligible effects. The enhanced drug release not only contributes to improved oral absorption but also has the potential to reduce the proportion of DAS that enters the environment through human excretion. This comprehensive approach highlights the significance of integrating advances in drug development while considering its environmental implications.
An extensive use of plastic material, which is a characteristic of modern society, is increasing the amount of plastic waste in the environment. Accordingly, plastic pollution has become a global ...environmental problem. The problem is particularly related to microsized and nanosized plastic particles which have become environmental contaminants of emerging concern. This research was focused on ecotoxicological aspects of 5 the most common plastic substances: polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET); all substances were in form of microplastics. The used test organism was freshwater microalgae
Chlorella
sp. and inhibition of the algal growth after 3-day exposure was measured. The experimental domain included microplastics in range 10–1000 mg/L and sizes 100–700 µm. Response surface modeling was applied in order to analyze the influence of these two parameters and statistical analysis of the obtained models was performed. The significance level was 95%. The obtained inhibitions were relatively low (< 6.79%) but
Chlorella
sp. showed sensitivity to changes in both tested parameters. A general behavior that included inhibition increase with higher concentration values and lower particle sizes was observed. The exception was PP where only the concentration proved to be significant parameter; the influence of the particle size remained insignificant for the selected experimental domain. Hormesis appears likely in PE and PP cases at particle sizes and concentrations that are below the experimental domain. Determined adverse influence of the applied plastics followed the order: PVC > PET > PS > PE > PP.
Graphical abstract
Microplastics (MP) are a global environmental problem because they persist in the environment for long periods of time and negatively impact aquatic organisms. Possible solutions for removing MP from ...the environment include biological processes such as bioremediation, which uses microorganisms to remove contaminants. This study investigated the biodegradation of polystyrene (PS) by two bacteria, Bacillus cereus and Pseudomonas alcaligenes, isolated from environmental samples in which MPs particles were present. First, determining significant factors affecting the biodegradation of MP-PS was conducted using the Taguchi design. Then, according to preliminary experiments, the optimal conditions for biodegradation were determined by a full factorial design (main experiments). The RSM methodology was applied, and statistical analysis of the obtained models was performed to analyze the influence of the studied factors. The most important factors for MP-PS biodegradation by Bacillus cereus were agitation speed, concentration, and size of PS, while agitation speed, size of PS, and optical density influenced the process by Pseudomonas alcaligenes. However, the optimal conditions for biodegradation of MP-PS by Bacillus cereus were achieved at γMP = 66.20, MP size = 413.29, and agitation speed = 100.45. The best conditions for MP-PS biodegradation by Pseudomonas alcaligenes were 161.08, 334.73, and 0.35, as agitation speed, MP size, and OD, respectively. In order to get a better insight into the process, the following analyzes were carried out. Changes in CFU, TOC, and TIC concentrations were observed during the biodegradation process. The increase in TOC values was explained by the detection of released additives from PS particles by LC-MS analysis. At the end of the process, the toxicity of the filtrate was determined, and the surface area of the particles was characterized by FTIR-ATR spectroscopy. Ecotoxicity results showed that the filtrate was toxic, indicating the presence of decomposition by-products. In both FTIR spectra, a characteristic weak peak at 1715 cm−1 was detected, indicating the formation of carbonyl groups (−C=O), confirming that a biodegradation process had taken place.
The improper disposal of plastics is a growing concern due to increasing global environmental problems such as the rise of CO
emissions, diminishing petroleum sources, and pollution, which ...necessitates the research and development of biodegradable materials as an alternative to conventional packaging materials. The purpose of this research was to analyse the properties of biodegradable polymer blends of thermoplastic potato starch (TPS) and polylactide, (PLA) without and with the addition of citric acid (CA) as a potential compatibilizer and plasticizer. The prepared blends were subjected to a comprehensive physicochemical characterization, which included: FTIR-ATR spectroscopy, morphological analysis by scanning electron microscopy (SEM), determination of thermal and mechanical properties by differential scanning calorimetry (DSC), water vapour permeability (
), as well as biodegradation testing in soil. The obtained results indicate an improvement in adhesion between the TPS and PLA phases due to the addition of citric acid, better homogeneity of the structure, and greater compatibility of the polymer blends, leading to better thermal, mechanical and barrier properties of the studied biodegradable TPS/PLA polymer blends. After conducting the comprehensive research outlined in this paper, it has been determined that the addition of 5 wt.% of citric acid serves as an effective compatibilizer and plasticizer. This supplementation achieves an optimal equilibrium across thermal, mechanical, morphological, and barrier properties, while also promoting material sustainability through biodegradation. In conclusion, it can be stated that the use of thermoplastic starch in TPS/PLA blends accelerates the biodegradation of PLA as a slowly biodegradable polymer. While the addition of citric acid offers significant advantages for TPS/PLA blends, further research is needed to optimize the formulation and processing parameters to achieve the desired balance between mechanical strength, thermal and barrier properties and biodegradability.
Utjecaj COVID-19 obrazaca ponašanja na ekosustave Hećimović, Dora; Mikuličić, Filip; Terzić, Ivana ...
Kemija u industriji; časopis kemičara i tehnologa Jugoslavije,
2024, Letnik:
73, Številka:
1-2
Journal Article
Recenzirano
Odprti dostop
Pandemija COVID-19 prouzročila je promjenu globalnoga razmišljanja i donijela svijetu neke nove i specifične obrasce ponašanja. Pandemijsko je razdoblje gotovo u potpunosti usmjerilo fokus na ...globalnu zdravstvenu krizu te su neke pretpandemijske cirkularne vrijednosti bivale zanemarivane. Stavljajući zdravlje svojih građana kao prioritetno, mnoge su se države i vlade ponovno okrenule linearnome gospodarstvu. Također, svjetska je populacija počela rapidnom brzinom konzumirati određene farmaceutike, pojavilo se (pre)naglašeno potenciranje osobne higijene i upotrebe dezinfekcijskih sredstava te se smanjenjem ljudskog kontakta ubrzano povećala potražnja i upotreba jednokratne plastike. Pojedini dijelovi industrije privremeno su se ugasili, no pojedini su sektori radili pojačanim intenzitetom, a prenapučenost zdravstvenih ustanova i neadekvatno zbrinjavanje medicinskog otpada i bolničkih otpadnih voda zadalo je specifičan udarac svjetskim ekosustavima. Tako se u okolišu odjednom našla neočekivano velika količina raznih farmaceutika, proizvoda za osobnu higijenu, jednokratne plastike, proizvoda za osobnu zaštitu, kao i medicinskog opasnog i neopasnog otpada. Stoga je iznimno važno sagledati širu sliku pandemijskih posljedica po okoliš te shodno tome donijeti adekvatna rješenja glede sprječavanja i smanjenja onečišćenja okoliša uzrokovanog pandemijom. Pojedina pandemijska ponašanja treba promijeniti, nastalu štetu sanirati i usmjeriti globalnu proizvodnju ka nekim novijim i održivijim tehnologijama. U ovome će se radu dati sažet pregled posljedica globalne zdravstvene krize na biosferu te perspektiva za potencijalno rješavanje nastalih problema i suzbijanje budućih katastrofa.
The COVID-19 pandemic has triggered a shift in global thinking and brought about new and specific behavioural patterns worldwide. The pandemic period was largely focused on the global health crisis, leading to the neglect of certain pre-pandemic circular values. In prioritizing the health of their citizens, many countries and governments reverted to linear economies. Furthermore, the world population witnessed a rapid increase in the consumption of certain pharmaceuticals, an (over)emphasis on personal hygiene and the use of disinfectants, and a surge in the demand for disposable plastics due to reduced human contact. While some industries experienced temporary shutdowns, others operated with increased intensity. Overcrowding in healthcare facilities coupled with inadequate disposal of medical waste and hospital wastewater, has inflicted a specific blow to global ecosystems. Consequently, an unexpectedly large quantity of various pharmaceuticals, personal care products, single-use plastics, personal protective equipment, and hazardous and non-hazardous medical waste has found its way into the environment. Therefore, it is crucial to consider the broader environmental consequences of pandemic-related behaviour and devise suitable solutions to prevent and reduce pandemic-induced environmental pollution. Certain pandemic-related behaviours need changing, existing damage requires remediation, and global production should be directed toward newer and more sustainable technologies. This paper provides a brief overview of the consequences of the global health crisis on the biosphere, and outlines perspectives for addressing encountered problems and mitigating future disasters.
The harmful effects of microplastics are not yet fully revealed. This study tested harmful effects of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), and ...polyethylene terephthalate (PET) microplastics were tested. Growth inhibition tests were conducted using three microorganisms with different characteristics:
sp.,
, and
. The growth inhibition test with
sp. is relatively widely used, while the tests with
and
were, to our knowledge, applied to microplastics for the first time. The influence of concentration and size of microplastic particles, in the range of 50-1000 mg/L and 200-600 µm, was tested. Determined inhibitions on all three microorganisms confirmed the hazardous potential of the microplastics used. Modeling of the inhibition surface showed the increase in harmfulness with increasing concentration of the microplastics. Particle size showed no effect for
with PE, PP and PET,
with PS, and
with PP. In the remaining cases, higher inhibitions followed a decrease in particle size. The exception was
sp. with PS, where the lowest inhibitions were obtained at 400 µm. Finally, among the applied tests, the test with
proved to be the most sensitive to microplastics.
In this study, a screening of the efficacy of a microbial consortium of bacteria and fungi isolated from activated sludge, river sediment, and compost for the degradation of LDPE/TPS was performed. ...According to the morphological and biochemical characterization, eight bacteria, Bacillus sonorensis, Bacillus subtilis, Lysinibacillus massiliensis, Bacillus licheniformis, Bacillus indicus, Bacillus megaterium, Bacillus cereus, and Pseudomonas alcaligenes, five molds, Aspergillus sp. 1, Aspergillus sp. 2, Trichoderma sp., Rhizopus sp., Penicillium sp., and Alternaria sp., and a yeast, Candida parapsilosis, were identified. The first experiment E1 was inoculated with microorganisms isolated from activated sludge and river sediment, and E2 with microorganisms isolated from compost. In both experiments, different types of polymeric materials, low density polyethylene (E1-1 and E2-1), thermoplastic starch (E1-2 and E2-2), low density polyethylene + thermoplastic starch (E1-3 and E2-3), low density polyethylene + thermoplastic starch + styrene-ethylene-styrene (E1-4 and E2-4) were added. The obtained results, weight loss, SEM, and FTIR analysis showed that the microorganisms in both experiments were able to degrade polymeric materials. The mixed culture of microorganisms in experiments E1-2 and E2-2 completely degraded TPS (thermoplastic starch). The percent weight losses of LDPE, LDPE+20% TPS, and LDPE+20% TPS+SEBS in experiment E1 were 3.3184%, 14.1152%, and 16.0062% and in experiment E2 were 3.9625%, 20.4520% and 21.9277%, respectively. SEM microscopy shows that the samples with a LDPE matrix exhibited moderate surface degradation and negligible oxidative degradation under the given conditions. FTIR/ATR data demonstrate that degradation was more intense in E2 than in E1.
Porastom osviještenosti čovjeka o negativnim učincima Sunčeva zračenja znatno se povećala proizvodnja i uporaba krema za sunčanje. Posljedica toga je akumulacija UV zaštitnih filtara, aktivnih ...sastojaka krema za sunčanje, u vodenom okolišu. Istraživanja su pokazala da su UV filtri, osobito organski filtri poput oksibenzona, oktinoksata i 4-MBC-a opasnost za čitav niz različitih organizama. Odabrana istraživanja u ovom radu usredotočena su na toksični učinak navedenih spojeva na morske i slatkovodne organizme te ukazuju na to da njihova prisutnost u vodenom okolišu rezultira inhibicijom rasta i fotosinteze, reproduktivnim i razvojnim poremećajima, izbjeljivanjem pa čak i smrću ispitivanih organizama. Anorganski UV filtri, čiji su predstavnici nanočestični oblici TiO2 i ZnO, u provedenim ispitivanjima ekotoksičnosti pokazuju slabo toksičan ili gotovo nikakav učinak na ispitivane organizme. Međutim, u istraživanjima u kojima su se pokazali slabo toksičnima, ta toksičnost nije uzrokovana samo prisutnošću nanočestica nego i stvaranjem reaktivnih vrsta kisika, što kod pojedinih organizama izaziva inhibiciju rasta, izbjeljivanje, abnormalnu embriogenezu i oksidativni stres. Daljnja istraživanja nužna su za bolje shvaćanje toksičnog učinka tih spojeva i precizniju procjenu rizika za vodeni okoliš te čitav ekosustav.
U današnjem modernom svijetu teško je zamisliti život bez uporabe nesteroidnih protuupalnih lijekova. Naime, zbog lake dostupnosti svjedočimo njihovoj sve većoj prisutnosti u svim sastavnicama ...okoliša, gdje najčešće završavaju zbog nepropisnog odlaganja ili putem otpadnih voda. Stoga je važno napomenuti da se nesteroidni protuupalni lijekovi najčešće mogu naći kao sastavni dio otpadnih voda porijeklom iz farmaceutskih industrija i bolnica te komunalnih otpadnih voda. Znanstvenici su postali svjesni da ti lijekovi u posljednjih nekoliko desetljeća predstavljaju veliku opasnost jer, osim što onečišćuju sve sastavnice okoliša, uzrokuju i negativne posljedice i na organizme prisutne u okolišu te se sve više vremena posvećuje provođenju testova ekotoksičnosti. Testovi ekotoksičnosti najbolje su rješenje za praćenje štetnih učinaka pojedinih tvari ili njihovih smjesa na organizme, pri čemu se može predvidjeti štetan učinak i na čovjeka. U ovom radu dan je pregled dosadašnjih istraživanja vezanih uz nesteroidne protuupalne lijekove te njihove uloge u hranidbenom lancu. Dodatno, dan je pregled više vrsta lijekova poput ibuprofena, diklofenaka i ketoprofena te opisan njihov učinak na određene organizme poput Daphnia magna, Danio rerio, Tinca tinca i Navicula sp.
Zeleni biokompoziti na bazi otpada taloga kave Ema Čemerika; Dora Milički; Martina Miloloža ...
Kemija u industriji; časopis kemičara i tehnologa Jugoslavije,
03/2023, Letnik:
72, Številka:
3-4
Journal Article
Recenzirano
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Stalni rast tržišta kave uzrokuju velike količine nastanka otpada taloga kave (OTK) koji čini i do 95 % otpada nakon konzumacije kave. OTK skriva bogatstvo različitih resursa, koje treba samo ...prevesti u neki drugi oblik, pogodan za uporabu. S druge strane, današnja prekomjerna proizvodnja plastičnog otpada uvelike uzrokuje ekološki poremećaj na globalnoj razini u gotovo svim aspektima industrije, što uzrokuje ubrzanu uporabu biorazgradivih polimera i biokompozita. Upravo zbog enormnih količina nastanka OTK i spore biorazgradnje polilaktida (PLA), u ovome istraživanju ispitana su svojstva i biorazgradivost zelenih biokompozita PLA_OTK pripremljenih umješavanjem matrice polilaktida s različitim udjelima otpada taloga kave. Toplinska svojstva biokompozita ispitana su diferencijalnom pretražnom kalorimetrijom (DSC) i termogravimetrijskom analizom (TGA). Ispitana je raspodjela veličina čestica otpada taloga kave metodom laserske difrakcije te apsorpcija vode (AV). Biorazgradnja biokompozita provedena je procesom kompostiranja tijekom 19 dana. Rezultati ispitivanja toplinskih svojstava pokazali su da OTK kao punilo ne utječe na fazne prijelaze PLA matrice, ali utječe na smanjenje toplinske stabilnosti biokompozita PLA_OTK. Rezultati ispitivanja apsorpcije vode pokazali su da povećanjem udjela OTK dolazi do povećanja apsorpcije vode u biokompozitima zbog hidrofilnog karaktera punila. Iz fotografija svjetlosnog mikroskopa vidljiv je površinski napad mikroorganizama kod biokompozita s manjim udjelom OTK, dok je dublji prodor vidljiv kod biokompozita s većim udjelom OTK kao punila.
