Valery M. Dembitsky

Chemical variability in the essential oil from leaves of individual plants of Majorana syriaca (common names Syrian marjoram, zaatar, zahtar) plants growing wild at various locations in Palestine were analyzed using a static headspace gas chromatography mass spectrometry (HS-GC/MS). Although Palestine represents a relatively small geographical area, a wide range of variations in oil characteristics were observed, indicating the Palestinian region as an important center of diversity. Essential oil yield was based on steam distillation of air-dried leaves ranged from 10.5 to 54 mg g⁻¹. The major oil constituents, α-phellandrene (1.62–8.13%), α-pinene (1.22%–4.61%), β-myrcene (0.5%–11%), m-cymene (1.86%–8.61%), p-cymene (8.44%–48.6%), γ-terpinene (11.96%–30.8%), thymol (0.26%–11.6%), and carvacrol (0.65%–21.7%), were identified throughout the harvesting period. An analysis of phenolic compounds revealed that wild growing Majorana syriaca could be characterized by the dominant presence of carvacrol. Conversely, water irrigation has showed a prominent effect on the thymol isomer production. Distribution of these isomers can be used as marker to distinguish wild from cultivated Majorana syriaca.

Fifteen species of wild edible mushrooms belonging to the genus Boletus (phylum Basidiomycota) were examined by high‐performance thin‐layer chromatographic (HP‐TLC) analysis and gas chromatography–mass spectrometry (GC‐MS) analysis for the presence of neutral, glyco‐, phospholipids, betaine lipids and fatty acids. The most abundant fatty acids were oleic acid (9‐18:1, 15–42%), linoleic acid (9,12‐18:2, 38–58%) and palmitic acid (16:0, 7–17%), but a great variation of the ester composition from one to another one was found. A comparison of neutral lipids, glycolipids, polar lipids and fatty acid composition of four species was done. Diacylglyceryltrimethylhomoserine and phosphatidylcholine were found as major components among polar lipids. Chemical constituents were characterized by GC‐MS, HP‐TLC and other chemical methods. Biologic activity of some isolated compounds from the genus Boletus is also discussed.PRACTICAL APPLICATIONS: Mushrooms are important wildlife food in the Mediterranean countries. The lipids of mushrooms, sampled from the Upper Galilee, Golan Heights and Mount Carmel areas, and also from the forest around Jerusalem, were examined. The benefits of including fatty acids in the diets of humans are well documented. Fatty acids play a major role in the functioning of the immune system and the maintenance of all hormonal systems in the body. Mushrooms from the genus Boletus are an excellent source of both fatty acids and neutral and polar lipids. Boletus mushrooms are one of the most popular treats in Israeli houses.

The present review describes research on novel natural cyclobutane-containing alkaloids and synthetic compounds isolated from terrestrial and marine species. More than 210 compounds have been confirmed to show antimicrobial, antibacterial, anticancer, and other activities. Structures, origins, biosynthesis, photodimerization, and biological activities of a selection of cyclobutane-containing alkaloids and selected synthethic analogs of natural alkaloids are reviewed.

Present review describes research on novel natural anticancer agents isolated from terrestrial and marine sources. More than 120 cytotoxic anticancer compounds have shown confirmed activity in vitro tumor cell lines bioassay and are of current interest to Natural Cancer Institute for further in vivo evaluation. Intensive searches for new classes of pharmacologically potent agents produced by terrestrial and marine organisms have resulted in the discovery of dozens of compounds possessing high cytotoxic activities. However, only a limited number of them have been tested in pre-clinical and clinical trials. One of the reasons is a limited supply of the active ingradients from the natural sources. However, the pre-clinical and clinical development of many terrestrial and/or marine-derived natural products into pharmaceuticals is often hampered by a limited supply from the natural source. Total synthesis is of vital importance in these situations, allowing for the production of useful quantities of the target compound for further biological evaluation. With computer program PASS some additional biological activities are also predicted, which point toward new possible applications of these compounds. This review emphasizes the role of terrestrial and marine peroxides as an important source of leads for drug discovery.

This review is a comprehensive survey of acetylenic lipids and their derivatives, obtained from living organisms, that have anticancer activity. Acetylenic metabolites belong to a class of molecules containing triple bond(s). They are found in plants, fungi, microorganisms, and marine invertebrates. Although acetylenes are common as components of terrestrial plants, fungi, and bacteria, it is only within the last 30 years that biologically active polyacetylenes having unusual structural features have been reported from plants, cyanobacteria, algae, invertebrates, and other sources. Naturally occurring aquatic acetylenes are of particular interest since many of them display important biological activities and possess antitumor, antibacterial, antimicrobial, antifouling, antifungal, pesticidal, phototoxic, HIV‐inhibitory, and immunosuppressive properties. There is no doubt that they are of great interest, especially for the medicinal and/or pharmaceutical industries. This review presents structures and describes cytotoxic and anticancer activities only for more than 300 acetylenic lipids and their derivatives isolated from living organisms.

This review presents more than 260 naturally occurring (as well as 47 synthesized) neo fatty (carboxylic) acids, neo alkanes, and their analogs and derivatives, isolated and identified from plants, algae, fungi, marine invertebrates, and microorganisms, that demonstrate different biological activities. These natural metabolites are good prospects for future chemical preparations as antioxidants, and also as anticancer, antimicrobial, and antibacterial agents. Described also are some synthetic bioactive compounds containing a tertiary butyl group(s) that have shown high anticancer, antifungal, and other activities. Applications of some neo fatty (carboxylic) acid derivatives in cosmetic, agronomic, and pharmaceutical industries also are considered. This is the first review to consider naturally occurring neo fatty (carboxylic) acids, neo alkanes, and other metabolites containing a tertiary butyl group(s) [or tert‐butyl unit(s)].