Antiproliferative activity of neem leaf extracts obtained by a sequential pressurized liquid extraction

Azadirachta indica A. Juss (neem) extracts have been used in pharmaceutical applications as antitumor agents, due to their terpenes and phenolic compounds. To obtain extracts from neem leaves with potential antiproliferative effect, a sequential process of pressurized liquid extraction was carried out in a fixed bed extractor at 25◦C and 100 bar, using hexane (SH), ethyl acetate (SEA), and ethanol (SE)assolvents. Extractions using only ethanol(EE) was also conducted to compare the characteristics of the fractionated extracts. The results obtained by liquid chromatography-electrospray ionization mass spectrometry suggested a higher concentration of terpenes in the SEA extract in comparison to SH, SE, and EE extracts. Therefore, antiproliferative activity showed that SEA extracts were the most efficient inhibitor to human tumor cells MCF-7, NCI-H460, HeLa, and HepG2. Hepatocellular cells were more resistant to SH, SEA, SE, and EE compared to breast, lung, hepatocellular, and cervical malignant cells. Neem fractioned extracts obtained in the present study seem to be more selective for malignant cells compared to the non-tumor cells.Klebson Silva Santos thanks CAPES (Process: PDSE 99999.003409/15-5) for the financial support during his Ph.D. studies in Portugal. Authors are grateful to CAPES, and FAPITEC (EDITAL CAPES/FAPITEC Nº 11/2016–PROEF/Processo de AUXPE 88881.157437/2017-01) for the financial support. The study was also carried out with financial support from FEDER, under the Partnership Agreement PT2020.info:eu-repo/semantics/publishedVersio

Cambuí (Myrciaria floribunda (West ex Willd.) O. Berg): A potential nutritional supplement for inhibition of COVID-19 infections / Cambuí (Myrciaria floribunda (West ex Willd.) O. Berg): Um potencial suplemento nutricional para a inibição de infecções por COVID-19

In the present study, we suggest that the Myrciaria floribunda (West ex Willd.) O. Berg fruit (cambuí) is a natural source of potential molecules against COVID-19. Extracts from orange and purple cambuí were obtained by using pressurized hot water extraction (PHWE). Extraction overall yield was 39.66 ± 1.62% and 33.00 ± 8.44% for the extracts of purple and orange cambuí, respectively. All analyzed extracts showed high total phenolic contents, especially those of purple fruits (3870.37 ± 353.09 mg GAE/100g). The total flavonoid content was 693.16 ± 180.09 and 770.08 ± 103.62 mg RE/100g for purple and orange fruit extracts, respectively. The secondary metabolite profile exhibited ellagic acid, ellagitannins, and derivatives of caffeic acid and ellagic acid. PHWE showed a good alternative for molecules separation from cambuí with promising potential for further in vitro and in vivo evaluation against Covid-19 infections

Beer Molecules and Its Sensory and Biological Properties: A Review

The production and consumption of beer plays a significant role in the social, political, and economic activities of many societies. During brewing fermentation step, many volatile and phenolic compounds are produced. They bring several organoleptic characteristics to beer and also provide an identity for regional producers. In this review, the beer compounds synthesis, and their role in the chemical and sensory properties of craft beers, and potential health benefits are described. This review also describes the importance of fermentation for the brewing process, since alcohol and many volatile esters are produced and metabolized in this step, thus requiring strict control. Phenolic compounds are also present in beer and are important for human health since it was proved that many of them have antitumor and antioxidant activities, which provides valuable data for moderate dietary beer inclusion studies

Silver Nanocomposite Biosynthesis: Antibacterial Activity against Multidrug-Resistant Strains of Pseudomonas aeruginosa and Acinetobacter baumannii

Bacterial resistance is an emerging public health issue that is disseminated worldwide. Silver nanocomposite can be an alternative strategy to avoid Gram-positive and Gram-negative bacteria growth, including multidrug-resistant strains. In the present study a silver nanocomposite was synthesized, using a new green chemistry process, by the addition of silver nitrate (1.10−3 mol·L−1) into a fermentative medium of Xanthomonas spp. to produce a xanthan gum polymer. Transmission electron microscopy (TEM) was used to evaluate the shape and size of the silver nanoparticles obtained. The silver ions in the nanocomposite were quantified by flame atomic absorption spectrometry (FAAS). The antibacterial activity of the nanomaterial against Escherichia coli (ATCC 22652), Enterococcus faecalis (ATCC 29282), Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923) was carried out using 500 mg of silver nanocomposite. Pseudomonas aeruginosa and Acinetobacter baumannii multidrug-resistant strains, isolated from hospitalized patients were also included in the study. The biosynthesized silver nanocomposite showed spherical nanoparticles with sizes smaller than 10 nm; 1 g of nanocomposite contained 49.24 µg of silver. Multidrug-resistant strains of Pseudomonas aeruginosa and Acinetobacter baumannii, and the other Gram-positive and Gram-negative bacteria tested, were sensitive to the silver nanocomposite (10–12.9 mm of inhibition zone). The biosynthesized silver nanocomposite seems to be a promising antibacterial agent for different applications, namely biomedical devices or topical wound coatings