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1

Methanolic leaf extract of Indigofera tinctoria mediated biosynthesis of zinc oxide nanoparticles

Rajab Arini, Wahab Abd. Wahid, Taba Paulina, Kasim Syahruddin, Arif Abdur Rahman, Fatimah, Yasser M.

Ecological Engineering & Environmental Technology

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2025

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Vol. 26, iss. 4

300--310

EN

Zinc oxide (ZnO) nanoparticles are multifunctional materials with wide application potential. The aim of this research is to synthesize ZnO nanoparticles utilizing Indigofera tinctoria leaf extract in methanol as an eco-friendly reducing and stabilizing agent. Synthesis was carried out with variations in extract mass, namely 1 g (Z1), 5 g (Z5), and 10 g (Z10) to evaluate the effect of the extract concentration upon the characteristics of the nanoparticles. FTIR, XRD, SEM, XRF, and UV-Vis DRS were used to characterize the samples. FTIR analysis results showed typical ZnO peaks at wave numbers 422-430 cm-1. XRD analysis revealed that the nanoparticles have a hexagonal wurtzite crystal structure with space group P63mc. The crystallite size decreased as the extract concentration increased, amounting to 16.55 nm (Z1), 15.21 nm (Z5), and 13.75 nm (Z10). The band gap energy value increased from 3.19 eV (Z1) to 3.21 eV (Z10), indicating an increase in optical activity at higher extract concentrations. Morphological analysis by SEM showed that all samples exhibited a quasi-spherical shape. EDS characterization revealed that only Zn and O elements were identified. XRF results confirmed the pristineness of ZnO nanoparticles, with a ZnO content of 98.99%. This research provides new insights into the potential use of Indigofera tinctoria leaf extract in the synthesis of ZnO nanoparticles, which can be utilized in various functional material and technology applications. These results also open up opportunities for the development of green synthesis methods for the fabrication of nanomaterials with characteristics that can be customized according to application needs.

2

Sustainable Producing of Oxalic Acid from Aspergillus niger and Candida albicans Isolated from Environmental and Clinical Sources

Jasim Amjad Ali, Al-Shibly Majid Kadhem

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 10

230--235

EN

Oxalic acid is one of the important acids that is used in many fields. It is of medical, industrial and agricultural importance and is used as an acid in foods, building and construction, pharmacy, and others. This acid is produced in multiple ways, and the biogenic method is the best method because it is safe and cheap. Hence, this study came about, where reliance was placed on wheat bran in preparing nutrient medium to produce oxalic acid from Candida albicans and Aspergillus niger yeast isolated from environmental and pathogenic sources. The study aimed to use wheat bran as an alternative medium for growing fungi and yeasts that produce oxalic acid, and to compare the productivity of this medium with standard media. One hundred fungal isolates were isolated from different environmental and clinical sources, and grown in Sabouraud dextrose agar medium (SDA) and potato dextrose agar to obtain pure isolates of A. niger and C. albicans. Thirty seven isolates of C. albicans and thirty two isolates of A. niger were isolated. Thirty one contaminated samples were discarded. The isolates were grown in standard (SDB, PDB) and alternative (wheat bran) media. The amount of acid was estimated by mulching against potassium permanganate. The results showed that wheat bran medium was the most efficient in producing oxalic acid with a rate of 26.2% for A. niger and 25.3% for C. albicans, compared to standard media. The best temperature for acid production was 32 °C with a production rate of 19.1% for A. niger and 22.7% for C. albicans. The best pH was 6.5 for A. niger with a production rate of 20.2% and 5.5 for C. albicans with a production rate of 23.3%. The study conclude from the above that the fungus A. niger is the best compared to C. albicans, as well as the medium of wheat bran is a promising and effective medium in the production of oxalic acid in an environmentally friendly way.

3

Green Chemistry Biosynthesis of Calcium Oxide Nanoparticles as Antibacterial Waste Microorganisms in Waters

Sultan Sahru, Karim Abdul, Permatasari Nur U.

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 12

233--252

EN

Calcium oxide (CaO) nanoparticles have garnered significant interest in various environmental applications, particularly in water treatment and the control of microbial pollution. This research introduces innovative strategies for water management and waste treatment through the application of advanced technology grounded in nanoscience, utilizing local resources. The primary objective of this study is to synthesize CaO nanoparticles via a green chemistry method, employing a bioreductant derived from the Bitti (Vitex cofassus) plant extract. This green chemistry approach is not only environmentally benign but also effective in producing stable nanoparticles with controlled dimensions. Characterization of the nanoparticles was conducted using X-ray diffraction (XRD) and scanning electron microscopy (SEM) to ascertain their crystal structure, morphology, and particle size. The results indicated that the calcium oxide nanoparticles exhibit a face-centered cubic (FCC) crystal phase, irregular surface morphology, and a spherical shape, with an average particle size of 24.87 nm. The antibacterial efficacy of calcium oxide nanoparticles was evaluated against Escherichia coli, with variations in nanoparticle concentrations of 1%, 3%, and 5%, resulting in average inhibition zone diameters of 9.59 mm, 10.78 mm, and 11.78 mm, respectively. The positive control (Chloramphenicol) demonstrated an inhibition zone of 12.65 mm, while the negative control (sterile water) showed no inhibition (0 mm). Similarly, for Staphylococcus aureus, the inhibition zone diameters with nanoparticle concentrations of 1%, 3%, and 5% were 10.26 mm, 11.15 mm, and 14.15 mm, respectively, with the positive control exhibiting an inhibition zone of 12.82 mm and the negative control showing no inhibition (0 mm). The CaO nanoparticles demonstrated greater efficacy against Staphylococcus aureus compared to Escherichia coli, exhibiting the capability to inhibit and eliminate both bacterial strains. The application of these nanoparticles as antibacterial agents presents a promising approach to effectively mitigate microbial waste in aquatic environments, suggesting their potential use as a solution for environmentally friendly microbial waste treatment.

4

Biogenic Fabrication of Iron and Zinc using Carob Seed Extract and their Antibacterial Activity

Farhan Zahrra Hamza, Al-Azawey Atheer Saieb Naji

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 10

17--30

EN

Biogenic synthesis of iron and zinc nanoparticles from carob seed extract (Ceratonia siliqua L.) and their antibacterial activity were studied. The characteristics of the prepared nanoparticles were evaluated shapes and sizes by field emission scanning electron microscopy (FESEM) analysis with mapping technique and energy dispersive X-ray analysis (EDX), and Fourier-transform infrared spectroscopy (FTIR) confirmed the functional group that contributes to the biogenic and antibacterial activity. The appearance of metal-oxygen bonds for both ZnO NPs and Fe2 O3 NPs in spectra and the presence of zinc, iron, and oxygen in varying proportions confirm the success of the biosynthesis of the nanoparticles. Ceratonia siliqua L. extract, iron, and zinc showed high effectiveness in removing bacteria from polluted water.

5

Overview of the plant-based synthesis of metal and metal oxide nanoparticles and their potential application in the formation of protective coatings

Duda Alicja, Kopyciński Bartosz

Ochrona przed Korozją

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2023

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nr 7

197--205

EN

Technologies for the production of nanomaterials have been developed for many years. Despite the remarkable achievements in this field, nanotechnologies contribute to serious environmental pollution. One of the interesting directions in the search for new, green solutions limiting their harmful impact on nature is the use of plant extracts as substrates in the techniques of synthesis of metal nanoparticles and metal oxides. This article briefly reviews the current state of knowledge on the preparation of metallic nanoparticles via green chemistry synthesis methods. The general mechanism of these processes is presented in an accessible way. In addition, current trends in the field of their use in the formulation of paints and varnishes with antifouling properties and as components of protective coatings preventing corrosion are discussed. A noteworthy way of using metallic nanoparticles in agriculture as a factor inhibiting the negative effects of salinity on the growth of crops was also mentioned. Despite the constantly growing number of scientific reports on these issues, this topic still requires a comprehensive discussion along with a detailed analysis of the synthesis processes. A comprehensive approach will certainly contribute to a better knowledge and understanding of this subject and the improvement of the quality of works devoted to the green synthesis of metallic nanoparticles.

PL

Technologie wytwarzania nanomateriałów są rozwijane od wielu lat. Pomimo niezwykłych osiągnięć w tej dziedzinie nanotechnologie przyczyniają się do poważnego zanieczyszczenia środowiska. Jednym z interesujących kierunków poszukiwania nowych, zielonych rozwiązań ograniczających ich szkodliwy wpływ na przyrodę jest wykorzystanie ekstraktów roślinnych jako substratów w technikach syntezy nanocząstek metali i tlenków metali. W artykule dokonano krótkiego przeglądu obecnego stanu wiedzy na temat otrzymywania nanocząstek metalicznych z użyciem metod syntezy biologicznej. W przystępny sposób przedstawiono ogólny mechanizm przebiegu tych procesów. Omówiono ponadto aktualne trendy w zakresie ich wykorzystywania w recepturowaniu farb i lakierów o właściwościach przeciwporostowych oraz jako składników powłok ochronnych zapobiegających korozji. Zwrócono również uwagę na kwestię zastosowania nanocząstek metalicznych w charakterze związków hamujących negatywny wpływ zasolenia na wzrost roślin uprawnych. Pomimo stale rosnącej liczby doniesień naukowych dotyczących tych zagadnień wciąż wymagają one kompleksowego omówienia wraz ze szczegółową analizą przebiegu procesów syntezy. Całościowe ujęcie z pewnością przyczyni się do lepszego poznania i zrozumienia tej tematyki oraz publikowania prac o wysokiej jakości.

6

Herbal Extract-Induced Silver Nanoparticles for Antibacterial Cotton Fabric

Rajput Sanjeev Kumar, Singh Mukesh Kumar, Shakyawar Dinesh Babu

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 3

22--29

EN

Herbal extract-induced metallic nanoparticles have replaced the traditionally synthesized nanoparticles to achieve sustainability in antimicrobial textiles. Silver nanoparticles (NPs) were created by the bio-reducion of silver nitrate with eucalyptus corymbia leaf extract. The bi-lateral activities of herbal extract, like the reduction and capping of silver nanoparticles, have added new dimensions in the bactericidal sector. Silver nanoparticles were characterized by UV-visible spectroscopy, a particle size analyzer, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and X-ray diffractometry. In this study these biosynthesized nanoparticles were applied on cotton fabric alone and along with chitosan by the pad-dry-cure method to create antibacterial clothing. Antibacterial efficiency was characterized using the colony counting method (serial dilution method). The treated fabric shows excellent antibacterial efficiency.

7

Photocatalytic purification of water on TiO2 photocatalysts produced with application of plant extracts

Rejek Maja, Kiełbasa Karolina, Grzechulska-Damszel Joanna

Inżynieria Materiałowa

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2019

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Vol. 40, nr 1

25--29

EN

Titanium dioxide is the most important photocatalyst used in the processes of the photocatalytic water treatment. Unfortunately, preparation of this material is energy consuming and requires application of toxic reagents, which is unfriendly to the environment. In this studies, TiO2 materials were biosynthesized using extracts form shamrock and walnut leafs to replace harmful compounds. Different TiO2 precursors were used: 1) titanium tetraizopropoxide (TTIP), 2) an intermediate product from titanium dioxide technological line in Grupa Azoty Zakłady Chemiczne “Police” SA. To prepare titanium dioxide, the individual extract was mixed with distilled water and titania precursor. The photocatalytic properties of prepared materials were tested in the reaction of decomposition of the model compound Acid Red 18, being an organic azo dye. The results revealed that the material prepared with TTIP shows the highest activity from all studied materials and decomposed the dye in 55 min. Application of various plant extracts has no much impact on the photoactivity of TiO2 photocatalyst — both materials decomposed Acid Red 18 in 55 min. Prepared materials were characterized by X-ray diffraction, nitrogen adsorption/ desorption process, diffuse reflectance UVVis and FTIR spectroscopy. Summarizing, each prepared material showed high photocatalytic activity so this preparation method seems to be appropriate for synthesis of active titania photocatalyst.

PL

Fotokataliza jest jedną z metod oczyszczania wody, która w ostatnich latach wzbudza coraz większe zainteresowanie naukowców, gdyż w większości przypadków powoduje rozkład zanieczyszczeń do wody, ditlenku węgla oraz kwasów nieorganicznych. Spośród wielu typów stosowanych fotokatalizatorów najczęściej badany jest ditlenek tytanu (TiO2), ponieważ charakteryzuje się dużą fotoaktywnością i stabilnością chemiczną, dobrymi właściwościami optycznymi, a co najważniejsze jest tani i łatwo dostępny. Niestety wytwarzanie tego materiału wymaga dużych nakładów energetycznych i zastosowania szkodliwych związków, co jest niekorzystne dla środowiska. Dlatego poszukuje się nowych, efektywnych i przyjaznych dla środowiska metod wytwarzania zarówno TiO2, jak i innych półprzewodników. Odpowiednią do tego metodą wydaje się biosynteza z użyciem ekstraktów roślinnych, ponieważ jest prosta, bezpieczna i przyjazna środowisku. W artykule przedstawiono nową metodę preparatyki TiO2: biosyntezę z użyciem ekstraktów z koniczyny białej i z liści orzecha włoskiego. W celu porównania użyto różnych prekursorów ditlenku tytanu: 1) tatraizopropanolanu tytanu (TTIP), 2) półproduktu z linii produkcyjnej TiO2 Zakładów Chemicznych „Police” SA: nieoczyszczonego (IP(A)) oraz płukanego wodą amoniakalną i wodą destylowaną (IP(W)). Właściwości fotokatalityczne wytworzonych materiałów sprawdzono, przeprowadzając szereg reakcji rozkładu związku modelowego: pąsu kwasowego (AR18), który jest barwnikiem azowym stosowanym głównie w przemyśle tekstylnym.

8

Influence of Different Plants Extracts on Silver Nanopar ticles Green Synthesis

Velgosova O., Mražíková A., Veselovský L., Willner J., Fornalczyk A.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 2

665--670

EN

Three plants extracts were used for biosynthesis of Ag nanoparticles (AgNPs). AgNPs nucleation process requires effective reduction agents which secure Ag+ to Ag0 reduction and also stabilizing/capping agents. The UV-vis and TEM observation revealed that the best results were obtained by R. officinalis leaf extract. The strong SPR band peak appeared at the wavelength 418 nm. Synthetized AgNPs were globular, fine (~20 nm), uniform and stabile throughout the experiment. A rapid rate of AgNPs synthesis was also significant and economically advantageous factor. Fine (10-20 nm) and globular nanoparticles were synthetized also by U. dioica leaf extract, but the stability of nanoparticles was not permanent. Despite V. vitis-idaea fruit extract contains a lot of reducing agents, UV-vis did not confirm the presence of AgNPs in solution. Synthetized Ag particles were very unstable, Ag particles agglomerated very fast and clearly indicated sediment was formed.

9

Zastosowanie rotatabilnego planu kompozycyjnego w optymalizacji składu podłoża hodowlanego do biosyntezy kwasu cytrynowego z glicerolu

Dymarska E., Janczar-Smuga M.

Przemysł Chemiczny

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2018

|

T. 97, nr 8

1276--1282

PL

Wykorzystano centralny rotatabilny plan czynnikowy II stopnia do ustalenia optymalnego składu podłoża hodowlanego do biosyntezy kwasu cytrynowego z użyciem glicerolu bezwodnego jako źródła węgla oraz identyfikowano model matematyczny opisujący wpływ stężenia glicerolu (X1) oraz stężenia makroelementów NH4NO3 (X2), KH2PO4 (X3), MgSO4·7H2O (X4) w podłożu hodowlanym na biosyntezę kwasu cytrynowego. Określono wpływ zmiennych niezależnych na końcowe stężenie produktu (Y1) oraz na współczynnik efektywności biosyntezy kwasu cytrynowego (Y2). W celu wyznaczenia wartości optymalnych zmiennych wejściowych, ze względu na dwa wybrane kryteria końcowe, wykorzystano metodę funkcji użyteczności. Największą wartość użyteczności wynoszącą 0,90 uzyskano dla stężeń glicerolu 150,0 g/dm3, NH4NO3 2,0 g/dm3, KH2PO4 0,2 g/dm3 oraz MgSO4·7H2O 0,2 g/dm3. Dla tak wyznaczonego składu podłoża hodowlanego przeprowadzono eksperyment weryfikacyjny, w wyniku którego uzyskano wartości wybranych kryteriów optymalizacji Y1 = 59,01 g/dm3 i Y2 = 7,00%·g/(dm3·h).

EN

Anhyd. glycerol was bioconverted to citric acid by using Aspergillus niger PD-66 on NH4NO3, KH2PO4, and MgSO4 – contg. substrates at 30°C and 200 rpm for 15 days. The results were evaluated statistically to det. the optimal final concns. of citric acid and biosynthesis efficiency coeff. from the resp. regression equations. A good agreement between the exptl. detd. and calcd. values was achieved.

10

Screening of silver-tolerant bacteria from a major Philippine landfill as potential bioremediation agents

Adriano J. S., Oyong G. G., Cabrera E. C., Janairo J. I. B.

Ecological Chemistry and Engineering. S

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2018

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Vol. 25, nr 3

469--485

EN

The field of microbial biotechnology has revolutionized the utilization of microorganisms to overcome the problems of environmental pollutions. The present study aimed to identify silver-tolerant isolates and screen their ability to synthesize silver nanoparticles for possible use as bioremediation agents. Seventeen bacterial isolates from soil collected from the Smokey Mountain landfill in Manila, Philippines, were found to tolerate 0.01 M AgNO3 in the culture medium. Molecular and phylogenetic analyses using the 16S rRNA gene sequence identified the isolates as Bacillus cereus, Bacillus subtilis, Bacillus flexus, Bacillus thuringiensis, Alcaligenes faecalis, Achromobacter sp. and Ochrobactrum sp. The formation of silver nanoparticles was evident in the change in color of the reaction mixtures, and was detected through UV-VIS spectroscopy with absorbance peaks at 250-300 nm and 400-450 nm. Scanning electron microscopy revealed the aggregation of diverse shapes of silver nanoparticles with sizes ranging from 70 to 200 nm. The best silver nanoparticle-synthesizing isolates were Alcaligenes faecalis and Bacillus cereus. The results denote the promising microbial technology application of the 17 silver-tolerant isolates in combating the adverse effects of metals and other pollutants in the environment.

11

Green synthesis, characterization and antibacterial activities of silver nanoparticles from strawberry fruit extract

Umoren S. A., Nzila A. M., Sankaran S., Solomon M. M., Umoren P. S.

Polish Journal of Chemical Technology

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2017

|

Vol. 19, nr 4

128--136

EN

Silver nanoparticles (AgNPs) have been synthesized in the presence of Strawberry fruit extract (SBFE) at room temperature. The synthesized AgNPs was characterized by UV-vis spectroscopy, SEM, EDS, XRD, TEM and FTIR. The UV-vis spectra of the AgNPs show SPR band at 450 nm. TEM results indicate that AgNPs are spherical in shape and size range between 7–65 nm. Antibacterial activity of the synthesized AgNPs has been assessed against Pseudomonas aeruginosa and Bacillus licheniformis. The results show that AgNPs exhibit inhibitory effect and effect is a function of AgNPs concentration. The antibacterial activity of the prepared AgNPs has been compared with two antibiotics, amoxicillin and ciprofloxacin. It is found that the antibiotics perform better than AgNPs.

12

Inorganic nanoparticles on bacteria: the key factors ruling the interaction

Duch J., Gołda-Cępa M., Ciura K., Kotarba A.

Engineering of Biomaterials

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2017

|

Vol. 20, no. 143 spec. iss.

29

13

Metody produkcji kwasu rycynolowego i jego estrów

Pabiś S., Kula J.

Przemysł Chemiczny

|

2016

|

T. 95, nr 4

759--765

PL

Kwas rycynolowy (kwas Z-12-hydroksyokta-9-decenowy) znajduje szerokie zastosowanie w wielu branżach przemysłowych ze względu na swoją strukturę i dostępność. Jego najbogatszym naturalnym źródłem jest olej rycynowy otrzymywany z nasion rącznika pospolitego (Ricinus communis L.). Czołowa pozycja tego kwasu tłuszczowego wśród oleochemikaliów o przemysłowym znaczeniu oraz pewne trudności związane z jego otrzymywaniem z oleju sprawiają, że prowadzone są liczne prace dotyczące nowych sposobów pozyskiwania tego związku, także z innych źródeł. Przedstawiono najnowsze doniesienia traktujące na temat surowców roślinnych o dużej zawartości kwasu rycynolowego oraz jego otrzymywania metodą zarówno chemicznej, jak i enzymatycznej hydrolizy acylogliceroli. Część publikowanego materiału dotyczy ciągle aktualnej i usprawnianej produkcji kwasu rycynolowego w postaci estrów, metodą transestryfikacji. Przedstawiono także najnowsze wyniki biosyntezy tego składnika prowadzące do dużej jego akumulacji, głównie dzięki zastosowaniu genetycznie modyfikowanych mikroorganizmów.

EN

A review, with 53 refs., of prodn. by chem. or enzymic hydrolysis, transesterification and biosynthesis.

14

Peptydoglikan : budowa, rola biologiczna oraz synteza

Samaszko-Fiertek J., Dmochowska B., Madaj J.

Wiadomości Chemiczne

|

2015

|

[Z] 69, 7-8

513--540

EN

The most important component of bacterial cell walls especially Gram-positive bacteria is peptidoglycan, called also murein, PGN. The first time this synonym was used in 1964 by Weidel and Pelzer [1]. Peptidoglycan is present in the outer layer of the cytoplasmic membrane and its structure. The structure of peptidoglycan depends on the bacteria strain. It is estimated that in Gram-negative bacteria, it occupies only about 10–20% of the total area of the cell wall, when in Gram-positive bacteria it is 50 and up to 90% of all space. Problems with isolation with high purity of biological material shows the need for developing techniques for chemical synthesis of peptidoglycan fragments and their analogs. In past few years there has been a growing interest within the synthesis of compounds glycoprotein (glycopeptides, peptidoglycan, etc.). As a basis for the construction of cell walls of many bacteria. Despite intensive research and gain significant knowledge of the physical and biological, chemical synthesis or biosynthesis (Fig. 5 and 6) of peptidoglycan, not so far failed to unambiguously determine its three-dimensional structure. The works of Kelman and Rogers [15] and Dimitriev [20] nearer picture of its structure. However, the time to develop in vivo visualization of cell structure it will be difficult to identify correctly peptidoglycan three-dimensional structure. Due to the important biological roles of murein, many research centers have taken to attempt their chemical synthesis. For biological research began to use chemically synthesized peptidoglycan fragments which guaranteed both uniform and a certain structure. An important roles in the development of methods of chemical synthesis of peptidoglycan had H. Chowdhury work, Fig. 8 [35], Hesek, Fig. 9 and 10 [36, 37], Dziarskiego [38] and Boneca [39] and Inamury [34, 40].

15

Biosynteza lakazy w obecności mineralnych cząstek tlenku glinu w podłożu

Antecka A., Blatkiewicz M., Bizukojć M., Ledakowicz S.

Inżynieria i Aparatura Chemiczna

|

2015

|

Nr 3

65--66

PL

W pracy przedstawiono badania wpływu obecności mineralnych cząstek tlenku glinu w podłożu hodowlanym na morfologię grzybni i produkcję lakazy przez Cerrena unicolor. Dodatek mikrocząstek powodował wzrost aktywności lakazy we wszystkich badanych stężeniach. Z praktycznego punktu widzenia stężenie tlenku glinu 15 g/dm3 uznano za wartość optymalną ze względu na wysoki poziom aktywności oraz całkowite wbudowanie tlenku glinu. Wzrost stężenia tlenku glinu powodował zmniejszenie wielkości peletek, ich powierzchnia stawała się silniej owłosiona aż do uzyskania grzybni rozproszonej przy stężeniu 30g/dm3.

EN

The influence of aluminium oxide particles in the culture medium on laccase biosynthesis and fungal morphology was studied. The results show the positive effect of microparticles at all tested concentrations of aluminium oxide. The concentration of 15 g/l was selected as the optimal one because of high laccase activity and complete incorporation of aluminium oxide to biomass. The higher concentration of aluminium oxide caused the decrease in pellets size and their surfaces got more hairy up to transformation into dispersed morphology at the concentration of 30 g/l.

16

Trehaloza – właściwości, biosynteza, zastosowanie

Burek M., Waśkiewicz S., Wandzik I., Kamińska K.

Chemik

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2015

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Vol. 69, nr 8

469--476

PL

α,α-Trehaloza jest naturalnie występującym disacharydem, zbudowanym z dwóch cząsteczek glukozy połączonych wiązaniem α,α- 1,1’-O-glikozydowym. Znana jest głównie ze zdolności do stabilizacji białek w warunkach stresu środowiskowego oraz hamowania ich agregacji. Po opracowaniu wielkotonażowej, biotechnologicznej metody produkcji, trehaloza znalazła liczne zastosowania w różnych gałęziach przemysłu, głównie w przemyśle spożywczym, kosmetycznym, farmaceutycznym i medycynie. Dowiedziono, że właściwości bioprotekcyjne trehalozy zostają zintensyfikowane w przypadku jej glikopolimerów.

EN

α,α -Trehalose is naturally occurring disaccharide composed of two glucose molecules linked by α,α -1,1’-O-glycosydic bond. It is primarily known from its ability to protect proteins during environmental stresses and inhibition of their aggregation. The development of largescale bioprocess has allowed to use trehalose in various applications, mainly in the food, cosmetic and pharmaceutical industry as well as in medicine. It was reported that bioprotective properties are amplified when trehalose is incorporated in polymer chain as a pendant group.

17

Kwas cynamonowy i jego hydroksypochodne : synteza i praktyczne zastosowanie

Guzik U., Hupert-Kocurek K., Siupka P., Wojcieszyńska D.

Przemysł Chemiczny

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2013

|

T. 92, nr 4

458-462

18

Biosynteza 6-n-pentylo-6H-piran-2-onu przez grzyby z rodzaju Trichoderma odporne na fungicydy

Gębarowska E., Szumny A., Adamski M., Pietr S. J.

Przemysł Chemiczny

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2013

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T. 92, nr 5

746-749

19

Biosynthesis of silver nanoparticles by a Bacillus sp. of marine origin

Janardhanan A., Roshmi T., Varghese R. T., Soniya E. V., Mathew J., Radhakrishnan E. K.

Materials Science Poland

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2013

|

Vol. 31, No. 2

173--179

EN

This study was aimed to explore the nanoparticle synthesizing properties of a silver resistant Bacillus sp. isolated from a marine water sample. The 16SrDNA sequence analysis of the isolate proved it as a Bacillus strain. Very interestingly, the isolate was found to have the ability to form intracellular silver nanoparticles at room temperature within 24 hours. This was confirmed by the UV-Vis absorption analysis which showed a peak at 430 nm corresponding to the plasmon absorbance of silver nanoparticles. Further characterization of the nanoparticles was carried out by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis. The presence of silver nanoparticles with the size less than 100 nm was confirmed. These particles were found to be extremely stable as confirmed by the TEM analysis after three months of purification. So, the current study is the demonstration of an efficient synthesis of stable silver nanoparticles by a marine Bacillus strain.

20

Droga pod słońce. Wczesna historia witaminy D

Wicha J.

Wiadomości Chemiczne

|

2012

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[Z] 66, 7-8

671-696

EN

Two natural products are called „vitamin D”: (1) vitamin D3 which is biosynthesized in humans and animals and (2) vitamin D2 which is generated in photochemical rearrangement of a sterol of fungy – ergosterol (Fig. 1 and 2). The vitamins D are further metabolized (Scheme 1) first into 25-hydroxy- and then into 1.,25-dihydroxy derivatives in various tissues. The compounds control the calcium transport and act as a cell growth regulator important for tumor prevention. The early history of vitamin D stems from outburst of rickets at the beginning of the industrialization era. Rickets was a child bond disease that often led to a permanent disability. A comprehensive description of the rickets was presented by D. Whistler ( 1619–1684) and then F. Glisson (1597–1677) and coauthors. Jędrzej Śniadecki ( 1768–1838) was the first who associated the rickets with the sunlight. In his book “On the Physical Education of Children” Śniadecki stated that exposition of a child’s body to a direct action of sunlight is the most efficient method for the prevention and the cure of rickets (Illustrations 1 and 2). T. A. Palm in 1890 observed that the rickets is rare in countries where sunshine is abundant and prevalent whenever there is a little of sunlight. The first experimental evidence on the sunlight effects in rickets were presented by J. R aczyński in 1912 who postulated that the sunlight affects metabolic processes in blood related to calcium transport (Illustration 3 and 4). E. Mellanby showed (1919) that the disease is connected to the lack of certain dietary factors and he recommended the use of cod liver – oil. K. Huldschinsky experimentally proved that UV irradiation cures the rickets. The Mellanby’s and Huldschinsky’s observations were confirmed by clinical studies in 1922. E.V. McCollum has developed efficient methods for “biological analysis” of food and named anti-rachitic factor as vitamin D.H. Steenbock and A.F. Hess in 1924 found independently that various food products gain anti-rachitic properties after being irradiated with a UV lamp. A.F. Hees and A. Windaus showed that irradiation of ergosterol affords a product with high anti-rachitic activity. In 1919 the first structure for cholesterol has been proposed by A. Windaus (Scheme 2, Fig. 3) and then with contribution of H. Wieland it was modified to the “Wieland-Windaus” structure (1928, Nobel Price lectures, Fig. 4). O. Diels’ investigation on dehydratation of cholesterol (Fig. 5) and J.D. Bernal’s crystallographic measurements of ergosterol challenged the Wieland-Windaus structure. Finally, the correct structure for cholic acid and sterols was deduced by O. Rosenheim and H. King (Fig. 6). In 1932 crystalline vitamin D2 was prepared in the Windaus laboratory (Scheme 3). In 1935 vitamin D3 was isolated from a fish-oil and the same compound was synthesized from cholesterol (Illustration 5). The structure of vitamin D2 was elucidated by Windaus in 1935 (Illustration 6) and confirmed by X-ray studies in 1948. Scientific contributions of Adolf Windaus are associated with his highest ethical standards and non-conformist political position in the national-socialist age.