Current Bioactive Compounds - Volume 11, Issue 2, 2015

Water-distilled essential oil from aerial parts of Hypericum scabrum L. (Hypericaceae) collected from the central part of Turkey was analyzed by GC/MS. It was characterized by α-pinene (74%), β-pinene (4.8%) and myrcene (3.4%). The oil and the main components were investigated for their mosquito deterrent, antimalarial and antimicrobial activities. Hypericum scabrum essential oil showed higher biting deterrent activity against Aedes aegypti than the solvent control, but the activity was significantly lower than the positive control, DEET. The oil exhibited antimalarial activity with IC50 values of 28.8 µg/mL and 15.7 µg/mL against the D6 and W2 strains of Plasmodium falciparum, whereas the major compounds (α-pinene, β-pinene and myrcene) were inactive up to 4.7 µg/mL. The H. scabrum oil showed selective antimicrobial activity against Cryptococcus neoformans (IC50=34.71 µg/mL), Mycobacterium intracellulare (IC50=52.98 µg/mL) and Candida krusei (IC50=104.43 µg/mL). No antimicrobial activity was detected for the enantiomers α-pinene, β-pinene and myrcene up to 20 µg/mL. The biting deterrent and antimalarial activity of H. scabrum oil were investigated for the first time.

The essential oil of Callitris intratropica is composed to a considerable proportion of rather unique lactones like callitrin (I), callitrisin (II) and columellarin (III) (Fig. 1) [1-7]. During the investigation of the volatiles obtained by hydrodistillation of the wood of this Cupressaceae species [8] we noticed that the oil yield increases with distillation time while the oil composition is shifted more and more towards the high boiling components. To find the reason for this behavior some wood was extracted in a Soxhlet apparatus and the resulting red-brown resinous oil analyzed by GC-MS-FID on a short GC column. The lignans deoxypodorhizon (IV) and deoxypodophyllotoxin (V) [9 -11] were disclosed and present in rather large amounts. Since the wood is available in large quantities this finding points out a new rich source [12 - 14] of these potent bioactive lignans.

Diseases that are vectored by mosquitoes, such as malaria and dengue, have important associated economic impacts in countries with tropical and subtropical climates because they have significant detrimental impacts on the workforce. Decreasing susceptibility and resistance have been ever-present threats since the introduction of synthetic insecticides. Compounding this is our inability to identify or create new major classes of pesticides since the discovery of pyrethroids. Plants rich in bioactive biodegradable phytochemicals of less toxicity to the environment are thought to provide the solution. This review specifically examines available research on the mosquitocidal activity of eighty-one species of plant seeds. The essential oils from seeds were found to demonstrate a range of larvicidal, adulticidal, growth regulating, ovicidal, oviposition deterrent, and repellent activities. The lethal concentrations and toxicity of more highly active botanicals are comparable to those of organophosphates, which makes them potential candidates for future laboratory investigation and field evaluation.

Grape pomace is an abundant agro-industrial residue that could be used as a source of natural antioxidants, when using appropriate techniques for their extraction. The solid-liquid extraction of bioactive compounds from grape pomace was optimized by experimental design. Temperature, ethanol, and Tween 80 amounts were evaluated by measuring the total phenolic content and the antioxidant activity of samples using the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) methods. Optimal condition of extraction was: 75 ºC; ethanol amount, 28.8 %; Tween 80 amount, 5 %. The total phenolic content was 21.55 mg gallic acid equivalent/gdw, whereas the antioxidant activity was 9.13 mmol TEAC (Trolox equivalent antioxidant capacity)//gdw and 178.34 mmol TEAC/gdw, respectively. The variables showed to significantly affect the total phenolic content (p < 0.05), but only temperature and ethanol amount influenced the antioxidant activity. Results suggest that ethanol could be used to replace non-food grade and environmentally problematic organic solvents, while the use of Tween 80 could improve the solid-liquid extraction.

The essential oil obtained from the aerial parts of Zilla macroptera Coss. (Brassicaceae), endemic species of the south of Algeria and southeast of Morocco, was analysed by GC and GC – MS. The analysis revealed 72 compounds accounting for 88.53 % of the oil. Geranyl butyrate (13.52%), Caryophyllene oxide (6.76%) and Carvone oxide (5.97%) were the main compounds of Z. macroptera Coss. This paper presents the rst detailed study of the essential oil composition of Z. macroptera Coss.

The anticancer activity of mistletoe (Viscum album L.) lectins and proteins extracts has been demonstrated in numerous in vitro and in vivo studies, including the validation of their clinical efficacy. Mistletoe tissue culture has been suggested as an approach for standardizing lectin biosynthesis, while the biosynthesis of novel lectins through somaclonal variation, i.e. the epigenetic modulation of the genome in vitro has also been demonstrated. However, the tumor cytotoxic properties of these novel molecules have not been assessed. PC12 pheochromocytoma and RAW 264.7 macrophage cell cultures were treated with protein extracts from “normal” and somaclonally variant mistletoe callus cultures, as well as donor plants used as positive control. Mistletoe callus-derived extracts demonstrated a concentration-dependent cytotoxicity in cancer cell lines, which was significantly higher compared to donor plants. Extracts from somaclonal cultures were even more potent against tumor cells. Our results suggest that somaclonally variant mistletoe callus cultures could be used as potential cell factories for the production of novel anticancer proteins.

Novels coumarin derivatives containing hydroxyl and alkyl groups on the aromatic ring were obtained through a hydroarylation reaction (1A-D) or by demethylation of bergapten (2A-C), and were then evaluated for their immunomodulatory and antimycobacterial activities. The immunomodulatory activity was evaluated in lipopolysaccharide (LPS)-stimulated mouse macrophage cells (RAW 264.7) by performing inhibition assays of nitric oxide (NO) and tumour necrosis factor (TNF-α) production. The cytotoxic effect was determined using a commercial lactate dehydrogenase (LDH) kit and MTT assay. The antimycobacterial activity of the coumarin derivatives was evaluated against Mycobacterium bovis BCG using the MTT method. Coumarin 1D was able to inhibit almost 80% of NO production, even at 4 µg/mL, exhibiting an IC50 value of 3.08±2.36 µg/mL. Our results indicate that the brominated substituents, despite their chain length, increased this activity, which is in contrast to the furan ring that caused a decreased in activity. For all of the tested compounds, the observed activities were not affected by their cytotoxicity to macrophages. For the TNF-α inhibitory activity, substituents -O(CH2)nBr and -OCH3 seem to be important, as observed in 1C and 1D (IC50 19.61±1.16 and 10.54±0.86 µg/mL, respectively). Compounds 1C and 2B were the most potent in the antimycobacterial assay, showing the lowest MIC50 value. All compounds containing bromine alkoxy significantly reduced NO and TNF-α production, with compounds 1C and 1D being the most promising, and they also showed antimycobacterial activity.

The essential oil was obtained by hydrodistillation from leaves of Warionea saharae and analyzed by GC-FID and GC-MS. Oxygen-containing terpene was the main group of constituents in both oil. This essential oil is rich in β-Eudesmol (32.87%), isomenthol (6.27%), Terpinyl butyrate (5.51%), Trans-nerolidol (5.31%), Linalool (4.99%), Terpinen-4-ol (3.55%) and Caryophyllane a (3.36%).

In this research, we tried to recover the antioxidant activities of grape pomace by means of using solid-state cultivation (SSC) of Aspergillus niger BLAn1, Phanerochaete chrysosporium BLPc1, and Penicillium sp. BLPen1, three GRAS strains of fungi. We measured the enzymatic activities of β-glucosidase, responsible for liberating the aglycone forms of the phenolic compounds, as well as their total content. The highest β-glucosidase activities were approximately 17.2, 8.3, and 13.5 U · g-1 pomace for the 3 strains, respectively. The enzyme activity was considerably reduced with moisture-saturated air injection in the system. The total phenolic content obtained were 21.15, 12.13, and 10.08 mg GAE (Acid galic equivalent) · g-1 pomace, whereas the highest antioxidant activities released were 16.30, 11.35, and 10.57 mmol TEAC (Trolox equivalent antioxidant capacity) · g-1 pomace (by DPPH assay), and 158.61, 104.68, and 102.55 mmol TEAC · g-1 pomace (by ABTS assay), for BLAn1, BLPc1, and BLPen1, respectively. These results suggest that the enzyme hydrolysis of phenolic glycosides leads to increased concentrations of free phenolic compounds, enhancing radical- scavenging potential of pomace.