Curcumin (1,7-bis-(4-hydroxy-3-methoxyphenyl)-hepta-1,6-diene-3,5-dione) is a natural lipophilic polyphenol that exhibits significant pharmacological effects in vitro and in vivo through various mechanisms of action. Numerous studies have identified and characterised the pharmacokinetic, pharmacodynamic, and clinical properties of curcumin. Curcumin has an anti-inflammatory, antioxidative, antinociceptive, antiparasitic, antimalarial effect, and it is used as a wound-healing agent. However, poor curcumin absorption in the small intestine, fast metabolism, and fast systemic elimination cause poor bioavailability of curcumin in human beings. In order to overcome these problems, a number of curcumin formulations have been developed. The aim of this paper is to provide an overview of recent research in biological and pharmaceutical aspects of curcumin, methods of sample preparation for its isolation (Soxhlet extraction, ultrasound extraction, pressurised fluid extraction, microwave extraction, enzyme-assisted aided extraction), analytical methods (FTIR, NIR, FT-Raman, UV-VIS, NMR, XRD, DSC, TLC, HPLC, HPTLC, LC-MS, UPLC/Q-TOF-MS) for identification and quantification of curcumin in different matrices, and different techniques for developing formulations. The optimal sample preparation and use of an appropriate analytical method will significantly improve the evaluation of formulations and the biological activity of curcumin.

Waste materials are receiving more attention as concerns about the future of our planet increase. Cellulose is the most common substance in agricultural waste. Agricultural wastes containing cellulose are misplaced resources that could be reused in various fields for both environmental and economic benefits. In this work, 32 different kinds of waste are investigated for chemical modification in order to obtain carboxymethyl cellulose for the production of a superabsorbent hydrogel that can be applied in agriculture. A brief literature review is provided to help researchers wishing to obtain carboxymethyl cellulose by carboxymethylation starting with waste materials. We also provide details about methods to obtain as well as verify carboxymethylation. Carboxymethyl cellulose (CMC), as a constituent of cellulosic water and superabsorbent hydrogels with applications in agriculture, is described. Superabsorbent hydrogels with CMC are able to absorb huge amounts of water and are biodegradable.

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Bilberry is considered as one of the most economically important wild berries. However, bilberry is not enough investigated, and there are only a few published works. Therefore, we performed in one place complete qualitative analysis, antimicrobial activity against different Gram-positive and Gram-negative bacteria and contents of metals. In our research, it was found that bilberry contains different active phenolic compounds, such as chlorogenic acid, delphinidin glycoside, delphinidin arabinoside, cyanidin glycoside, cyanidin arabinoside, malvidin glycoside, peonidin glycoside, and malvidin arabinoside. The content of metals was different in leaves and fruits. In our samples, the content of aluminum, boron, barium, calcium, cadmium, chromium, copper, iron, manganese, nickel, phosphorus, silicon and zinc was higher, and contents of potassium, magnesium, and sodium were lower than in bilberry samples investigated in Latvia. Antimicrobial activity of investigated extracts was evaluated against laboratory control strains from ATCC collection, Gram (+) bacteria: Staphylococcus epidermidis ATCC 12228, Staphylococcus aureus ATCC 6538, Streptococcus pyogenes ATCC 19615, Enterococcus faecalis ATCC 19433, Propionibacterium acnae ATCC 11827, and Gram (-) bacteria: Escherichia coli ATCC 9863, Pseudomonas aeruginosa ATCC 9027, Acinetobacter boumanii ATCC 196060, Proteus mirabilis ATCC 12453, Klebsiella pneumonia ATCC 10031, and against related strains isolated from human wound swabs. V. myrtillus extract was less potent against strains from wounds compared to ATCC strains as well Gram (-) bacteria compared to Gram (+) bacteria. The most sensitive strains were St. epidermidis, St. pyogenes, P. mirabilis and S. aureus.

Detailed GC and GC/MS analyses of essential-oil samples obtained by hydrodistillation of Morus alba L. and M. nigra L. leaves (four samples) allowed the identification of 131 constituents representing 95.1-96.4% of the total GC peak areas. The most abundant compounds classes were alkanes, diterpenoids, carotenoid-derived compounds and fatty acid-related constituents with trans-phytol (7.9-71.2%), (E,E)-geranyl linalool (0.2-8.0%), (Z)-bovolide (8.1%) and n-chain alkanes (in total, 17.5-52.4%) as the major constituents of the analyzed samples. In general, there were only quantitative differences noted between M. nigra essential oils from fresh and dry leaves. The most discernable changes included a variation in the content of the major constituents (e.g. the relative amount of trans-phytol and the total amount of alkanes decreased by 5.8% and ≈ 2%, respectively, while that of (E,E)-geranyl linalool increased by 7.8%). On the other hand, the composition of M. alba essential oil was much more significantly affected by the drying process. The highest quantitative differences were noted for trans-phytol, geranyl acetone, and all isomers of 4,6,8-megastigmatrien-3-one. Also, a rare plant metabolite, (Z)-bovolide, characteristic of leaf senescence, was only identified (8.1%) in the essential oil of M. alba dried leaves.