Insights into bioactivity guided chemical profiling of Ziziphus jujuba Mill. fruits wild-growing in Montenegro

Jujube (Ziziphus jujuba Mill.) is a highly abundant wild-growing plant in Montenegro. It has been utilized since old times for various bioactive properties by the natives, however its detailed chemical characterization, antimicrobial, antioxidant and cytotoxic potential have not been extensively explored. Herein, we used crud methanol extract and three fractions (methylene chloride, n-butanol and aqueous) to asses bioactive features of fruits from this wild growing edible plant, after which we performed the targeted analysis of phenolic compounds of n-butanol fraction by (UHPLC-DAD-MS/MS). Our antioxidant assays showed the highest radical scavenging potential for n-butanol fraction using DPPH and ABTS methods. As for the antimicrobial activity of extract and three fractions, generally aqueous showed the least promising antibacterial and antifungal properties, whereas methylene chloride, methanol and n-butanol fractions showed quite promising antimicrobial potential. E. coli and S. aureus strains were the most susceptible to the compounds present in the methylene chloride and n-butanol fractions with MIC of 0.01-0.025 mg/mL, and MBC 0.025-0.05 mg/mL, along with MRSA strain, which was the most susceptible to the effects of methanol extract with MIC of 0.10 mg/mL and MBC 0.15 mg/mL. The results of antifungal activity showed lower potential to inhibit growth of pathogenic fungi than bacteria, whereas cytotoxicity assay showed extracts have no effects towards HaCaT skin cell line.The n-butanol fraction had the overall most promising activity, and therefore was subjected to more in depth chemical analysis.

Comparative Content, Biological and Anticancer Activities of Heracleum humile Extracts Obtained by Ultrasound-Assisted Extraction Method

As the safety and effectiveness of synthetic drugs remain in doubt, researchers are trying to develop natural medicines from medicinal plants. Herein, ethyl acetate, methanol and water extracts from the Heracleum humile plant were obtained by an ultrasonic-assisted extraction process and the aim was to evaluate some biological effects of the extracts due to the limited data on the pharmacological properties of Heracleum humile in the literature. Weak antibacterial activity was observed on tested bacterial species. The minimum inhibitory concentration and the minimum bactericidal concentration values ranged from 250 to 500 μg/mL. In addition, cytotoxic activity was determined using the MTT test. The strongest findings were determined for ethyl acetate extract on the MDA-MB-231 cell lines at the 48^th  hour (IC₅₀ :97.94 μg/mL), followed by the MCF-7 cell lines at the 24^th  hour (IC₅₀ :103.9 μg/mL). All extracts of Heracleum humile contained mainly flavonoids, phenolic acids and their derivatives, i. e., well-known compounds that possess numerous biological activities such as antioxidant, anti-inflammatory, anticancer, antimicrobial etc. The study results could provide important information that Heracleum humile could be a potential candidate as a natural enzyme inhibitor. It can be concluded that these extracts could be useful in the elementary step of improving novel plant-derived multifunctional pharmaceuticals.

Phenolic-Rich Plant Extracts With Antimicrobial Activity: An Alternative to Food Preservatives and Biocides?

In recent years, the search for natural plant-based antimicrobial compounds as alternatives to some synthetic food preservatives or biocides has been stimulated by sanitary, environmental, regulatory, and marketing concerns. In this context, besides their established antioxidant activity, the antimicrobial activity of many plant phenolics deserved increased attention. Indeed, industries processing agricultural plants generate considerable quantities of phenolic-rich products and by-products, which could be valuable natural sources of natural antimicrobial molecules. Plant extracts containing volatile (e.g., essential oils) and non-volatile antimicrobial molecules can be distinguished. Plant essential oils are outside the scope of this review. This review will thus provide an overview of current knowledge regarding the promises and the limits of phenolic-rich plant extracts for food preservation and biofilm control on food-contacting surfaces. After a presentation of the major groups of antimicrobial plant phenolics, of their antimicrobial activity spectrum, and of the diversity of their mechanisms of action, their most promising sources will be reviewed. Since antimicrobial activity reduction often observed when comparing in vitro and in situ activities of plant phenolics has often been reported as a limit for their application, the effects of the composition and the microstructure of the matrices in which unwanted microorganisms are present (e.g., food and/or microbial biofilms) on their activity will be discussed. Then, the different strategies of delivery of antimicrobial phenolics to promote their activity in such matrices, such as their encapsulation or their association with edible coatings or food packaging materials are presented. The possibilities offered by encapsulation or association with polymers of packaging materials or coatings to increase the stability and ease of use of plant phenolics before their application, as well as to get systems for their controlled release are presented and discussed. Finally, the necessity to consider phenolic-rich antimicrobial plant extracts in combination with other factors consistently with hurdle technology principles will be discussed. For instance, several authors recently suggested that natural phenolic-rich extracts could not only extend the shelf-life of foods by controlling bacterial contamination, but could also coexist with probiotic lactic acid bacteria in food systems to provide enhanced health benefits to human.

Chemosystematic Significance of Essential Oil Constituents and Furanocoumarins of Underground Parts and Fruits of Nine Heracleum L. Taxa from Southeastern Europe

The composition of the essential oils and the furanocoumarin profiles of CH₂ Cl₂ extracts from underground parts and fruits of nine Heracleum taxa (Apiaceae) from Southeastern Europe were statistically analyzed to evaluate their chemosystematic significance. Eight investigated taxa (H. orphanidis and members of H. sphondylium group: H. sphondylium, H. sibiricum, H. montanum, H. ternatum, H. pyrenaicum subsp. pollinianum, H. pyrenaicum subsp. orsinii and H. verticillatum) belong to the type section of the genus. Additionally analyzed taxon, H. austriacum subsp. siifolium, belongs to H. sect. Wendia. Qualitative and quantitative analysis of the essential oils was performed by GC-FID and GC/MS, and of the furanocoumarins by LC/MS. Furanocoumarins were identified using standards and/or based on UV, MS, ¹ H- and ROESY NMR spectra. Multivariate statistics (PCA, nMDS, UPGMA) of analyzed metabolites showed that the investigated taxa were grouped according to their taxonomic classification. PCA revealed the significance of some monoterpenes and (Z)-falcarinol of the underground parts oils, octyl esters of the fruit oils, and most of the total of 12 identified furanocoumarins.

Effectiveness of omega-3 polyunsaturated fatty acids against microbial pathogens

Microorganisms provide both beneficial and harmful effects to human beings. Beneficial effects come from the symbiotic relationship that exists between humans and microbiota, but then several human illnesses have turned some friendly microbes into opportunistic pathogens, causing several microbial-related diseases. Various efforts have been made to create and utilize antimicrobial agents in the treatment and prevention of these infections, but such efforts have been hampered by the emergence of antimicrobial resistance. Despite extensive studies on drug discovery to alleviate this problem, issues with the toxicity and tolerance of certain compounds and continuous microbial evolution have forced researchers to focus on screening various phytochemical dietary compounds for antimicrobial activity. Linolenic acid and its derivatives (eicosapentaenoic acid and docosahexaenoic acid) are omega-3 fatty acids that have been studied due to their role in human health, being important for the brain, the eye, the cardiovascular system, and general human growth. However, their utilization as antimicrobial agents has not been widely appreciated, perhaps due to a lack of understanding of antimicrobial mechanisms, toxicity, and route of administration. Therefore, this review focuses on the efficacy, mechanism, and toxicity of omega-3 fatty acids as alternative therapeutic agents for treating and preventing diseases associated with pathogenic microorganisms.

Essential oils of three cow parsnips - composition and activity against nosocomial and foodborne pathogens and food contaminants

Although some widespread, native cow parsnips (Heracleum L. spp., Apiaceae) had broad medicinal and culinary applications throughout history, the knowledge about their volatile constituents is insufficient. This work investigates the composition and bioactivities of H. sphondylium L. (HSPH), H. sibiricum L. (HSIB) and H. montanum Schleich. ex Gaudin (HMON) essential oils. The composition was tested by GC and GC-MS. (Z)-β-Ocimene was the most abundant in HSPH (28.9%) and HMON (20.4%) root oils, while in HSIB root oil, β-pinene (26.2%), methyl eugenol (22.3%) and elemicin (25.6%) prevailed. Leaf and flower oils were dominated by various sesquiterpenes (germacrene D, β-sesquiphellandrene, (E)-β-farnesene and/or (E)-caryophyllene) and/or phenylpropanoids (apiole, methyl eugenol, elemicin and/or (Z)-isoelemicin). Octyl acetate (57.5-67.1%) was the main constituent of all fruit oils. The antimicrobial activity was screened by a microdilution method against eight bacteria and eight fungi. The strongest antimicrobial effect, in several cases better than the activity of antibiotics, was shown by HSPH (MICs = 0.12-3.30 mg mL^-1) and HMON (MICs = 0.10-1.30 mg mL^-1) flower oils against bacteria, and HSIB fruit oil against fungi (MICs = 0.15-0.40 mg mL^-1). The MTT test revealed that the oils were not or weakly cytotoxic against human malignant HeLa, LS174 and/or A549 cells (except HSPH root oil; IC₅₀ = 5.72-24.31 μg mL^-1) and that tested oils were not toxic against human normal MRC-5 cells (at 200.00 μg mL^-1). Significant activity observed against microorganisms that are the common cause of foodborne diseases, food contamination and/or hospital-acquired infections justifies certain traditional uses of the investigated plants and represents a good basis for further research of these Heracleum oils.

Biological activity and safety profile of the essential oil from fruits of Heracleum mantegazzianum Sommier & Levier (Apiaceae)

A composition of essential oils obtained from Heracleum mantegazzianum (Apiaceae) was examined using a GC-MS method. n-Octyl acetate (19.92%), n-hexyl-2-methylbutanoate (10.84%), n-octanol (10.13%), n-octyl butanoate (8.88%), n-octyl-2-methylbutanoate (8.01%), n-hexyl acetate (7.11%), n-octyl isobutanoate (5.5%) and n-hexyl isobutanoate (5.43%) were the main compounds. The high-performance counter-current chromatography was applied for purification of aliphatic alcohols and esters. A mixture of n-hexane, acetonitrile and tetr-butyl methyl ether (1:1:0.1, v/v) allowed to obtain n-octanol, n-octyl acetate, n-hexyl-2- methylbutanoate, n-octyl isobutanoate and n-octyl-2-methylbutanoate, with the purity range of 94-99%, in one single 74 min run. The antimicrobial activity was also determined against plant and foodborne pathogens. While n-octanol shares responsibility for the antibacterial activity of the essential oil, n-octyl acetate determines its antifungal action. The cytotoxic activity assessed on two normal kidney fibroblast cell lines: Vero (animal) and HEK-293 (human embryonic), and two human cancer cell lines: FaDu (squamous cell carcinoma of the pharynx) and SCC25 (squamous cell carcinoma of the tongue), showed a moderate cytotoxicity with CC₅₀ values ranging from 262.3 to 567.8 μg/mL. Results indicate that normal cell lines were more sensitive to the tested essential oil than cancer cell lines. The antioxidant activity of oil and pure compounds was not significant.