Volum 27 Nr. 5 (2022): Romanian Biotechnological Letters
Articole originale, recenzii de literatură, comunicări științifice scurte (de max. 3 pagini) în domeniul biotehnologiilor (verzi, rosii, albe, albastre, bioinformatică) și al cercetării interdisciplinare în medicină, neuroștiințe, agricultură, zootehnie, ecologie și protecția mediului.
Număr complet
Articles
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Synthesis of l-DOPA catalyzed by recombinant Escherichia coli expressing tyrosine phenol lyase gene from Desulfitobacterium hafniense
Rezumat
L-DOPA (L-dihydroxyphenylalanine) is a potential drug for the treatment of Parkinson’s disease, and the demand is increasing every year. Tyrosine phenol-lyase (TPL) is a valuable biocatalyst for the biosynthesis of L-tyrosine and its derivatives, which are valuable intermediates in the pharmaceutical industry. In this study, a new TPL gene (Dh-TPL) was cloned from Desulfitobacterium hafniense, ligated into pJJDuet30 vector, and successfully expressed in Escherichia coli. To increase the yield and stability of L-DOPA, as well as decrease the by-product formation, the enzyme production conditions and the catalytic reaction conditions were studied. The optimal TPL production conditions were as follows: the concentration of IPTG was 0.2 mmol/L and the induction temperature was controlled at 18°C. The optimum medium composition for recombinant bacteria includes yeast extract 64 g/L, tryptone 36 g/L, glycerol 4 g/L, KH2PO4 2.31 g/L and K2HPO4 9.4 g/L. The best biosynthesis of L-DOPA was performed in a reaction mixture containing 10.0 g/L catechol, 20 g/L sodium pyruvate and 20 g/L recombinant E. coli resting cells. The optimal reaction temperature and pH were determined to be 18°C and pH 8.5, respectively. Under these conditions, the yield of L-DOPA was 0.21 mol/L (41.7 g/L) after 3 hours reaction.
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Experimental research on the use of innovative phytoextracts in cow with clinical endometritis
Rezumat
Clinical endometritis is a frequent and important pathology on farms in Romania and not only, so we created and obtained a preparation exclusively from plants in different forms of administration (tablets and intrauterine solution), with which to treat the cows under study. We chose a group of cattle that we divided into 4 batches of cows, a control batch treated with classical medication, a batch treated with intrauterine solution, a batch treated only with tablets, and the fourth batch was treated
with tablets and intrauterine solution.
Based on a well-established working protocol and paraclinical investigations performed, it was demonstrated the usefulness of phytoextracts in the prevention and treatment of clinical endometritis, but also the way of stimulating the immune response associated with a shorter healing time. -
Biphasic response of epidermoid adenocarcinoma cells to curcumin and EGCG co-treatment
Rezumat
We investigated the combinatorial treatment of curcumin and epigallocatechin-gallate (EGCG) in human epidermoid carcinoma cell line A-431. When combined, concentrations of EGCG and curcumin lower than 25 μM increased proliferation, but 50 μM curcumin led to near complete proliferation/viability inhibition. As reference, the compounds were CCD-1070Sk, where they did not show any toxicity, except in the highest concentration sample. In A-431 cell line, curcumin and EGCG combinations induced cell death by apoptosis, collapse of thee also tested on normal FIbroblast cells, mitochondrial membrane depolarization (ΔΨm) and increase the cell number in S phase of cell cycle.
Nevertheless, the most powerful compound in inducing the above effects was curcumin. Next, we have shown that EGCG scavenged ROS produced by 25 μM curcumin with an EC50 of 44.34 μM EGCG.
In conclusion, curcumin and EGCG combinations exert ΔΨm collapse, cell death and cell cycle arrest in A-431 cells at concentrations not affecting the viability of normal skin fibroblasts. -
Epidemiology, diagnosis, symptoms and TNM classification of head and neck cancers
Rezumat
Head and neck cancers occur predominantly by transformation of squamous cells lining the mucous membranes of the upper aerodigestive tract and affect one of the most complex regions of the human body. Head and neck cancers are very common, with more than half a million new cases annually, and have a mortality rate of around 50%, and early diagnosis can improve treatment outcomes and increase the life expectancy of those affected. In this paper, we review the epidemiology, the main symptoms, the diagnostic methods, highlighting the few genetic markers identified so far, and the TNM classification of each type of upper aerodigestive cancer.
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Streptomyces lasiicapitis KSA18 isolated from Saharan soil in Algeria effective against most bacteria and fungi
Rezumat
Saharan soil still represents a formidable source of microorganisms that produce bioactive substances. Twentythree Actinobacteria strains were isolated from sand samples collected from saharian field in Algeria. Isolates were evaluated for antimicrobial activity. After primary screening, 79% of the isolates showed antimicrobial activity. KSA18 strains were selected for their intense activity. Bioactive metabolite was extracted with ethyl acetate and tested against pathogens microorganisms using the disk diffusion method. The crude extract was partially purified by column chromatography and evaluated for antimicrobial activity. Fraction A1 showed good activity against Staphylococcus aureus (3.25 mg/mL) and Listeria monocytogenes (4 mg/mL). This strain has been identified as Streptomyces lasiicapitis by 16S rRNA sequencing. GC-MS analysis of crude extract showed the presence of about 17 different volatile compounds). Some of them could be directly responsible for antibacterial or antifungal activity. The most important compounds are Phenol, 2,4-Bis(1,1-Dimethylethyl), 3-Isobutylhexahydropyrrolo[1,2-A] Pyrazine-1,4-Dione, 2-methyloctacosane and dibutyl phthalate.
However, this study requires other approaches to identify the bioactive molecules present in the extract. -
Antibiotics and antibiotic resitant bacteria: from hotspots into the aquatic environment
Rezumat
There is a vast literature on the occurrence of antibiotics and antibiotic resistant bacteria (ARB) of human or animal origin in natural aquatic ecosystems as result of anthropogenic activitie. Although hotspots for AR discharge in the environment were identified, that include: sewage and wastewater treatment plants (WWTP), industrial drug manufacurers, food and animal production, agriculture and aquaculture, and clinical settings such as hospitals, efficient current regulations to mitigate this pollution are lacking. The aim of this review is to provide insights regarding the spread of antibiotics and ARB from hotspots into aquatic environment and also an overview of current EU and UN regulations for combating AR pollution of our natural ecosystems.
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SARS CoV-2 virus and the COVID-19 pandemic worldwide and in Romania. An updated data review
Rezumat
SARS CoV-2 is a coronavirus first identified in November-December 2019 in Wuhan, China that causes respiratory infections of varying severity. Spreading rapidly in human populations, SARS CoV-2 has caused concern worldwide, and on 11 March 2020 the World Health Organization declared a pandemic with the virus for two months, with most countries entering a lockdown period between March and May 2020 in the hope of stopping the spread of the virus. The main symptoms of SARS CoV-2 infection include fever, cough, shortness of breath and fatigue, but less common symptoms such as loss of smell and taste and gastrointestinal disturbances including vomiting, lack of appetite, diarrhoea, etc. are also reported. From March 2020 to March 2023, there were eight waves of increasing numbers of infections, the largest being the sixth wave between January and April 2022. The total number of deaths also followed roughly the same trends with the increase in newly confirmed cases.
As an RNA virus with RNA-dependent RNA polymerase, SARS CoV-2 mutates frequently, leading to the stabilisation of several variants: B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.614.2 (Delta), B.1.427 and B.1.429 (Epsilon), P.2 (Zeta), B1.525 (Eta), P.3 (Theta), B.1.617.1 (Kappa) and C.37 (Lambda). The severity of some cases and the intense spread in human populations around the
world has led the scientific community to focus its efforts on developing effective vaccines against SARS CoV-2, with nine approved vaccines being developed, BNT162b/2, mRNA-1273, AZD1222 Covishield, Sputnik V rAd26 rAd5, Ad26. CoV.S JNJ-78436735, COVAXIN BBVI52, Corona Vac, NVX-CoV2373 Covavax and BBIBP-CoV vaccines, with which a large part of the global population has been immunised.
