Lavandoside from <Emphasis Type="Italic">Lavandula spica</Emphasis> flowers

The new natural compound lavandoside with the structure ferulic acid 4-O-β-D-glucopyranoside was isolated by column chromatography over silica gel and polyamide from the extract of Lavandula spica flowers. The chemical structure of lavandoside was established using UV, NMR, and mass spectra and chemical transformations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 133–134, March–April, 2008.     

Unusual molecular pattern in Ajugoideae subfamily: the case of Ajuga genevensis L. from Dolomites

We analysed the ethanolic extract from Ajuga genevensis L. (Lamiaceae) growing in Dolomites, part of Italian Alps. Three new compounds for this species were identified: rosmarinic acid (1), oleanolic acid (2) and maslinic acid (3), representative of two different classes of chemical compounds (phenylpropanoids and pentacyclic triterpenes). A. genevensis resulted to be a valuable source of these compounds endowed with interesting biological activities (i.e. antioxidant, neuroprotective, anti-inflammatory, antiproliferative). The recognition of compounds (1), (2) and (3) may also confirm the ethnomedicinal uses of this plant. From a chemotaxonomical point of view, it is worth noting that iridoids were not evidenced in this accession. Iridoids are considered chemotaxonomic marker in Lamiales, and, in contrast with a previous study on this species, the presence of aucubin was not confirmed. In addition, the presence of large amounts of rosmarinic acid (1) was unexpected for a species that does not belong to subfamily Nepetoideae.     

Bioactive Abietane-Type Diterpenoid Glycosides from Leaves of Clerodendrum infortunatum (Lamiaceae)

In this study, two previously undescribed diterpenoids, (5R,10S,16R)-11,16,19-trihydroxy-12-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-17(15→16),18(4→3)-diabeo-3,8,11,13-abietatetraene-7-one (1) and (5R,10S,16R)-11,16-dihydroxy-12-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-17(15→16),18(4→3)-diabeo-4-carboxy-3,8,11,13-abietatetraene-7-one (2), and one known compound, the C₁₃-nor-isoprenoid glycoside byzantionoside B (3), were isolated from the leaves of Clerodendrum infortunatum L. (Lamiaceae). Structures were established based on spectroscopic and spectrometric data and by comparison with literature data. The three terpenoids, along with five phenylpropanoids: 6′-O-caffeoyl-12-glucopyranosyloxyjasmonic acid (4), jionoside C (5), jionoside D (6), brachynoside (7), and incanoside C (8), previously isolated from the same source, were tested for their in vitro antidiabetic (α-amylase and α-glucosidase), anticancer (Hs578T and MDA-MB-231), and anticholinesterase activities. In an in vitro test against carbohydrate digestion enzymes, compound 6 showed the most potent effect against mammalian α-amylase (IC₅₀ 3.4 ± 0.2 μM) compared to the reference standard acarbose (IC₅₀ 5.9 ± 0.1 μM). As yeast α-glucosidase inhibitors, compounds 1, 2, 5, and 6 displayed moderate inhibitory activities, ranging from 24.6 to 96.0 μM, compared to acarbose (IC₅₀ 665 ± 42 μM). All of the tested compounds demonstrated negligible anticholinesterase effects. In an anticancer test, compounds 3 and 5 exhibited moderate antiproliferative properties with IC₅₀ of 94.7 ± 1.3 and 85.3 ± 2.4 μM, respectively, against Hs578T cell, while the rest of the compounds did not show significant activity (IC₅₀ > 100 μM).     

Recent Developments in Therapeutic and Nutraceutical Applications of p-Methoxycinnamic Acid from Plant Origin

The p-methoxycinnamic acid (p-MCA) is one of the most studied phenylpropanoids with high importance not only in the wide spectrum of therapeutic activities but also its potential application for the food industry. This natural compound derived from plants exhibits a wide range of biologically useful properties; therefore, during the last two decades it has been extensively tested for therapeutic and nutraceutical applications. This article presents the natural sources of p-MCA, its metabolism, pharmacokinetic properties, and safety of its application. The possibilities of using this dietary bioactive compound as a nutraceutical agent that may be used as functional food ingredient playing a vital role in the prevention and treatment of many chronic diseases is also discussed. We present the antidiabetic, anticancer, antimicrobial, hepato-, and neuroprotective activities of p-MCA and methods of its lipophilization that have been developed so far to increase its industrial application and bioavailability in the biological systems.     

Probing occurrence of phenylpropanoids in Morinda citrifolia in relation to foliar diseases

Accumulation of phenolic compounds in cell walls of different plant organs leading to increased lignification is an early defence response of plants against biotic stress. The aim of this work was to delineate occurrence of cell wall-bound (CWB) phenolic compounds in Morinda citrifolia leaves. Alkaline hydrolysis of the cell wall material of leaf tissues yielded 4-coumaric acid (4-CA) as the major bulk of the phenolic compounds in all Morinda germplasms. Next in line was 4-hydroxybenzoic acid. Other phenolics identified were vanillic acid, 4-hydroxybenzaldehyde, vanillin and ferulic acid. Concentrations of all the CWB phenolics were highest in the germplasm CHN-5, followed by the germplasm CHN-1. Incidentally, these two Morinda germplasms recorded lowest incidence of foliar diseases. Significantly higher amounts of 4-CA in combination with other phenolics may be the reasons for lowest incidence of foliar diseases in CHN-5 and CHN-1 germplasms of M. citrifolia.     

Two new phenylpropanoids from the Chinese mangrove Ceriops tagal

Two new phenylpropanoids, tagalphenylpropanoidins A-B (1–2), together with a known analogue, 2,3,6-trimethoxy-5-(1-propenyl)phenol (3), were isolated from the ethanolic extract of the Chinese mangrove Ceriops tagal. The structures of these compounds were determined by extensive spectroscopic analysis, including 1D and 2D NMR and HR-ESI-MS, as well as the comparison with data in the literature. Compound 3 was discovered from this plant for the first time. Cytotoxicities of the three compounds against MCF-7 and HL-60 cancer cell lines were also evaluated.     

Phenylpropanoids from Medicinal Plants: Distribution, Classification, Structural Analysis, and Biological Activity

The literature and our own research results on phenylpropanoids from medicinal plants were reviewed and systematized. Data were presented for the distribution of phenylpropanoids. Their classification was proposed. The biological structure-activity relationships for compounds found in roseroot (Rhodiola rosea), thorny eleutherococcus (Eleutherococus senticosus), common lilac (Syringa vulgaris), purple echinacea (Echinacea purpurea), medicinal melissa (Melissa officinalis), variegated milk-thistle (Silybum marianum), and others were discussed.     

Phenylpropanoids in radioregulation: double edged sword

Radiotherapy, frequently used for treatment of solid tumors, carries two main obstacles including acquired radioresistance in cancer cells during radiotherapy and normal tissue injury. Phenylpropanoids, which are naturally occurring phytochemicals found in plants, have been identified as potential radiotherapeutic agents due to their anti-cancer activity and relatively safe levels of cytotoxicity. Various studies have proposed that these compounds could not only sensitize cancer cells to radiation resulting in inhibition of growth and cell death but also protect normal cells against radiation-induced damage. This review is intended to provide an overview of recent investigations on the usage of phenylpropanoids in combination with radiotherapy in cancer treatment.     

Toxics or Lures? Biological and Behavioral Effects of Plant Essential Oils on Tephritidae Fruit Flies

The family Tephritidae (Diptera) includes species that are highly invasive and harmful to crops. Due to globalization, international trade, and human displacement, their spread is continuously increasing. Unfortunately, the control of tephritid flies is still closely linked to the use of synthetic insecticides, which are responsible for detrimental effects on the environment and human health. Recently, research is looking for alternative and more eco-friendly tools to be adopted in Integrated Pest Management (IPM) programs. In this regard, essential oils (EOs) and their main compounds represent a promising alternative to chemical insecticides. EOs are made up of phytoconstituents formed from the secondary metabolism of many plants and can act as attractants or toxics, depending on the dose. Because of this unique characteristic, EOs and their main constituents are promising tools that can be used both in Sterile Insect Technique (SIT) programs and in the “lure and kill” technique, exploiting the attractiveness of the product in the former case and its toxicity in the latter. In this article, current knowledge on the biological and behavioral effects of EOs and their main constituents on tephritid fruit flies is reviewed, mainly focusing on species belonging to the Anastrepha, Bactrocera, Ceratitis, and Zeugodacus genera. The mechanisms of action of EOs, their real-world applications, and challenges related to their use in IPM are critically discussed.     

Phenolic compounds: antioxidant and larvicidal potential of Smilax brasiliensis Sprengel leaves

Abstract

Smilax brasiliensis is a medicinal species of the Brazilian Cerrado. The extract and fractions of this plant were analysed by LC-DAD-MS. Identified constituents included glycosylated and non-glycosylated flavonoids, especially quercetin, and phenylpropanoids, such as chlorogenic acids. The antioxidant activity was significantly more pronounced for the methanol extract and fractions than that of the commercial antioxidant 2,6-di-tert-butyl-4-methylphenol (BHT). Maximum larvicidal activity of 85.83% was recorded in the dichloromethane fraction (LC₅₀ = 469.78?µg mL^?1). The methanol extract and fractions presented low toxicity to larvae of the shrimp brine Artemia salina, indicating selectivity for C. quinquefasciatus. These results contribute to the phytochemical study of S. brasiliensis. These compounds were identified for the first time in this species and encourage additional work on the isolation of compounds present in the extract and fractions of S. brasiliensis to evaluate the possibility of using them as natural sources of antioxidants, since cytotoxic effects were not demonstrated.