New Findings from Natural Substances

The genus Heliotropium is formed of herbaceous plants belonging to the family Boraginaceae. In Chile and around the world, many Heliotropium species are commonly used in traditional and complementary medicine to treat various diseases. Members of this genus are also recognized for unique biosynthesized phytochemicals, mainly terpenoids, phenolics and alkaloids. Due to important phyto-constituents, as well as their therapeutic potential, many Heliotropium species have been subjected to chemical, biological and pharmacological investigations. This review details the many ethnomedicinal uses for Heliotropium, with an emphasis on Chilean species, and analyzes their scientific validation based on the chemical constituents and pharmacological properties of Heliotropium reported in academic publications. In addition, we discuss the critical conclusions, as well as some suggestions for future phytochemical and biological studies with Heliotropium species.

Essential oils (EOs), or the volatile fraction produced by aromatic plants, possess a large number of biological activities. In the last few years, their possible use in anticancer therapy has been under investigation. The anticancer potential of EOs against leukemic diseases and their chemical composition have been reported in this chapter, highlighting the in vitro studies against different cell models with their cytotoxicity and the corresponding mechanism of action.

Herbs are key players in many traditional health care systems that have been used in medical practices since ancient times. The beneficial therapeutic effects of these medicinal plants resulted from the combinations of their secondary metabolite. Nowadays, the use of natural compounds is increasing around the world due to their relatively mild potentials and low side effects, Polyphenols are the most important compounds that exhibit diverse activities. Among these polyphenols, rosmarinic acid (RA) attracted much attention from the researchers since it was isolated as the main compound in many plants, like those of the Boraginaceae and Lamiaceae families such as Rosmarinus officinalis (rosemary) and Ocimum baslicum (sweet basil). It is an ester of caffeic acid and 3,4-dihydroxy phenyl lactic acid, which has a wide spectrum of biological, pharmacological and medicinal properties that can be useful in many pathological conditions. Moreover, it presents anti-inflammatory effects, which are attributed to the inhibition of lipoxygenase and cyclooxygenases and interference with the complement cascade. Furthermore, RA has been shown to prevent cell damage caused by free radicals, thereby reducing the risk of cancer. On the other hand, it also exerts powerful hypolipidemic, antioxidant, anti-atherosclerotic, anticancer and even hepato-protective activities. The current chapter aims to highlight the therapeutic potential of RA against a wide range of diseases. Given the current evidence, rosmarinic acid can be used as part of the daily intake in the treatment of several diseases, with predefined doses preventing cytotoxicity.

 The medicinal plants are widely used to treat diverse ailments and diseases, including gastro-intestinal symptoms, cardiovascular diseases, skin disorders, respiratory and infectious diseases, accelerating in recent years. Plants are rich in a wide variety of secondary metabolites, such as alkaloids, tannins, flavonoids, and phenolic compounds, found in vitro to have antimicrobial properties and could assist in the discovery of novel drugs. The search for novel antimicrobial compounds, especially against multidrug-resistant pathogens from aromatic and herbal plants, is an essential line of scientific research. This review attempts to summarize the in vivo studies of the antimicrobial activity of medicinal plants and their biologically active compounds. The chemical composition of biologically active compounds with antimicrobial is also addressed.

Astragalus genus has been recorded as yielding a wide range of flavonoids, triterpenes, triterpene saponins, and polysaccharides. Cycloartane- and oleanane-type triterpenes are widely distributed in this genus with intriguing biological effects. Combining liquid chromatography (LC) with high-resolution mass spectrometry (HRMS) has provided a valuable tool in the analysis of these triterpenes in plants. In this chapter, we summarized the main triterpenes studied by liquid chromatography highresolution mass spectrometry (LC-HR-MS) associated with mass analysers, molecular weight information and mass fragmentation, presenting an interesting overview of increasing interest for cycloartane- and oleanane-type triterpenes.

Oxidative stress is implicated in the pathophysiology of aging and agerelated health conditions, such as cancer, cardiovascular disorders and neurodegenerative diseases; therefore, the supplementation of diet with plant-derived antioxidants is recognized as a potential strategy to delay or even prevent the onset of age-related diseases. Among the model organisms commonly used in the early phases of anti-aging drug discovery, the nematode Caenorhabditis elegans has proven useful for investigating the bioactivity of complex extracts and isolated plant secondary metabolites. In this chapter, we have reviewed recent studies on the antioxidant, longevity-promoting and neuroprotective activities of polyphenol-rich plant extracts in C. elegans, with particular focus on the highly conserved insulin/IGF-1 signaling pathway. 

 Since ancient times, olive oil has been part of human culture. It is the main source of fatty acids in the Mediterranean diet and has beneficial effects on human health. Due to its high content of monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and polyphenols, it is generally considered one of the best sources of fat. Among its health properties, olive oil can counteract LDL cholesterol, and protect against cardiovascular diseases and furthermore, its biomolecules (such as polyphenols) can positively interact with oxidative stress, carcinogenesis and arteriosclerosis. Oleuropein and hydroxytyrosol (HTyr) are characteristic phenols of olive oil. Oleuropein is hydrolyzed by endogenous βglycosidases to produce HTyr. The beneficial effect of olive oil on oxidative stress is largely due to HTyr and its derivatives. Furthermore, HTyr exhibits antioxidant, antitumor, anti-inflammatory, cardioprotective and neuroprotective activities. The search for synthetic compounds derived from HTyr can be an interesting way to enhance their biological activities and / or to discover other properties. HTyr can be obtained from crusher wastewater, which is considered a good source of Htyr. 

Hydrodistillation is a traditional method that has long been used to extract essential oils and hydrolates from plant matrices known to be rich in bioactive compounds. The use of water as a solvent in the process does not require the recovery of the solvent, with a saving in terms of time, energy, loss of volatile compounds, and a lower environmental impact. Very often, and for some matrices rich in essential oils, hydrolates are considered a by-product. They contain a variety of organic phytochemicals which can be extracted and used for other medicinal, cosmetic, dermatological, and commercial applications. Extracts derived from different plant parts, such as leaves, roots, stems, bulbs, fruits, flowers, and seeds, vary in characteristics and composition. Many other variables can influence the composition of hydrolates, such as geographic location, cultivation techniques, seasonality, and process variations. Plant hydrolates contain significant quantities of bio compounds with different activities: they can be used as antimicrobial, sanitizing, or antitumor agents for the control of weeds, nematodes, larvae, and various parasites affecting crops of agronomic interest, as well as anesthetizing in aquaculture. These extracts are also used in aromatherapy or as components in cosmetic formulations. The hydrolate represents a matrix of considerable interest due to the greater ease of diffusion on specific substrates and the lower toxicity compared to essential oil.