-
1.
Ultrastructural and metabolic disorders induced by short-term cadmium exposure in Avicennia schaueriana plants and its excretion through leaf salt glands.
Mizushima, MYB, Ferreira, BG, França, MGC, Almeida, AF, Cortez, PA, Silva, JVS, Jesus, RM, Prasad, MNV, Mangabeira, PAO
Plant biology (Stuttgart, Germany). 2019;(5):844-853
Abstract
Environmental cadmium (Cd) sources have increased in mangrove sediments in recent decades, inducing cellular damage to many plants. Avicennia schaueriana is abundant in mangrove sites and has been subject to Cd contamination. The possible effects of Cd toxicity and the structural and physiological disturbances to this plant were studied. Can this plant express early cellular tolerance mechanisms to such metal contamination? Seedlings of A. schaueriana were collected from sites of their natural occurrence, placed in plastic pots containing nutrient solution for 60 days, and subsequently exposed to increasing Cd concentrations for 5 days under experimental conditions. The anatomical, ultrastructural and physiological changes induced by Cd were analysed. Cd accumulated mainly in the root system and in pneumatophores, stems and leaves, induced differential accumulation of mineral nutrients, but did not induce necrosis or changes in leaf anatomy. However, there was a decrease in starch grains and an increase in deposited electron-dense material in the cortex and vascular bundles. Cd induced both increases in calcium (Ca) content in shoots and Ca oxalate crystal precipitation in leaf mesophyll and was detected in crystals and in the secretion of salt glands. Our observations and experimental results provide evidence of Cd tolerance in A. schaueriana. As a new feature, despite the clear cellular physiological disorders, this plant is able to eliminate Cd through leaf salt glands and immobilise it in Ca crystals, representing fast mechanisms for Cd exclusion and complexation in leaves in heavy metal coastal polluted marine ecosystems.
-
2.
Cytotoxic Limonoids from the Twigs and Leaves of Toona ciliata.
Zhu, GL, Wan, LS, Peng, XR, Shi, QQ, Li, XN, Chen, JC, Zhou, L, Qiu, MH
Journal of natural products. 2019;(9):2419-2429
Abstract
Eight new limonoids, toononoids A-H (1-8), eight new B-seco-29-norlimonoids, toonanoronoids A-H (9-16), and seven known analogues were obtained from the EtOAc extract of the twigs and leaves of Toona ciliata. Compounds 2, 4, 8, and 16 are rare lactam-bearing limonoids. Compounds 1, 14, and 15 possess an unusual γ-methoxybutenolide moiety at C-17, while compounds 9, 10, and 15 have a rare 3β-hydroxy group. Their 2D structure and relative configurations were identified using spectroscopic data. The absolute configurations of 1, 9, 14, and 15 were established via X-ray diffraction crystallography or comparison of experimental and calculated ECD data. The cytotoxicity of the compounds was assessed toward five human tumor cell lines, and their anti-inflammatory activity was assessed based on NO production using LPS-stimulated RAW264.7 macrophages. Compounds 11 and 12 exerted inhibition toward two tumor cell lines (MCF-7, SW-480) with IC50 values between 2.1 and 3.7 μM, while 18-22 inhibited the proliferation of HL-60, MCF-7, and SW-480 cells (IC50 0.6-4.0 μM). Only compound 4 exhibited weak anti-inflammatory activity with an IC50 value of 28.3 μM.
-
3.
Sesquiterpene Lactones from Artemisia argyi: Absolute Configuration and Immunosuppressant Activity.
Reinhardt, JK, Klemd, AM, Danton, O, De Mieri, M, Smieško, M, Huber, R, Bürgi, T, Gründemann, C, Hamburger, M
Journal of natural products. 2019;(6):1424-1433
Abstract
A library of extracts from plants used in Chinese Traditional Medicine was screened for inhibition of T lymphocyte proliferation. An ethyl acetate extract from aerial parts of Artemisia argyi showed promising activity and was submitted to HPLC-based activity profiling to track the active compounds. From the most active time window, three guaianolides (1, 2, and 5) and two seco-tanapartholides (3 and 4) were identified and, in a less active time window, five new sesquiterpene lactones (8-11, 17), along with six known sesquiterpene lactones and two known flavonoids. The absolute configurations of compounds 1, 2, 5-10, 13-15, 17, and 18 were established by comparison of experimental with calculated electronic circular dichroism (ECD) spectra. For seco-tanapartholides B (3) and A (4), ECD yielded ambiguous results, and their absolute configurations were determined by comparing experimental and calculated vibrational circular dichroism (VCD) spectra. Compounds 1-5 showed significant, noncytotoxic inhibition of T lymphocyte proliferation, with IC50 values between 1.0 and 3.7 μM.
-
4.
Dry olive leaf extract attenuates DNA damage induced by estradiol and diethylstilbestrol in human peripheral blood cells in vitro.
Topalović, D, Dekanski, D, Spremo-Potparević, B, Pirković, A, Borozan, S, Bajić, V, Stojanović, D, Giampieri, F, Gasparrini, M, Živković, L
Mutation research. Genetic toxicology and environmental mutagenesis. 2019;:402993
Abstract
Phenolic groups of steroidal or nonsteroidal estrogens can redox cycle, leading to oxidative stress, where creation of reactive oxygen species are recognized as the main mechanism of their DNA damage properties. Dry olive (Olea europaea L.) leaf extract is known to contain bioactive and antioxidative components and to have an ability to modulate the effects of various oxidants in cells. The main goal of this study was to investigate antigenotoxic potential of a standardized dry olive leaf extract on DNA damage induced by 17β-estradiol and diethylstilbestrol in human whole blood cells in vitro, using comet assay. Our results indicated that both hormones showed a genotoxic effect at a concentration of 100 μM (P < 0.05, n = 6). Dry olive leaf extract was efficient in reducing number of cells with estrogen-induced DNA damage at tested concentrations (0.125, 0.5 and 1 mg/mL) (P < 0.05, n = 6) and under two experimental protocols, pre-treatment and post-treatment, exhibiting antigenotoxic properties. Analysis of antioxidant properties of the extract revealed moderate ABTS radical scavenging properties and reducing power. Overall, our results suggested that the protective potential of dry olive leaf extract could arise from the synergistic effect of its scavenging activity and enhancement of the cells' antioxidant capacity.
-
5.
Effects of body size and root to shoot ratio on foliar nutrient resorption efficiency in Amaranthus mangostanus.
Peng, H, Yan, Z, Chen, Y, Zhao, X, Han, W
American journal of botany. 2019;(3):363-370
Abstract
PREMISE OF THE STUDY Nutrient resorption is essential for plant nutrient conservation. Large-bodied plants potentially have large nutrient sink pools and high nutrient flux. Whether and how nutrient resorption can be regulated by plant size and biomass allocation are yet unknown. METHODS Using the herbaceous plant Amaranthus mangostanus in greenhouse experiments for two consecutive years, we measured plant biomass, height, and stem diameter and calculated the root to shoot biomass ratio (R/S ratio) and nutrient resorption efficiency (NuRE) to assess the effects of plant body size and biomass allocation on NuRE. NuRE was calculated as the percentage reduction in leaf nutrient concentration from green leaf to senesced leaf. KEY RESULTS NuRE increased with plant biomass, height, and stem diameter, suggesting that the individuals with larger bodies, which led to a larger nutrient pool, tended to resorb proportionally more nutrients from the senescing leaves. NuRE decreased with increasing root to shoot ratio, which might have reflected the nutrient acquisition trade-offs between resorption from the senescent leaves and absorption from the soil. Increased root biomass allocation increased the proportion of nutrient acquisition through absorption more than through resorption. CONCLUSIONS This study presented the first experimental evidence of how NuRE is linked to plant size (indicated by biomass, height, and stem diameter) and biomass allocation, suggesting that nutrient acquisition could be modulated by the size of the nutrient sink pool and its partitioning in plants, which can improve our understanding of a conservation mechanism for plant nutrients. The body size and root to shoot ratio effects might also partly explain previous inconsistent reports on the relationships between environmental nutrient availability and NuRE.
-
6.
Boron Deficiency Effects on Sugar, Ionome, and Phytohormone Profiles of Vascular and Non-Vascular Leaf Tissues of Common Plantain (Plantago major L.).
Pommerrenig, B, Eggert, K, Bienert, GP
International journal of molecular sciences. 2019;(16)
Abstract
Vascular tissues essentially regulate water, nutrient, photo-assimilate, and phytohormone logistics throughout the plant body. Boron (B) is crucial for the development of the vascular tissue in many dicotyledonous plant taxa and B deficiency particularly affects the integrity of phloem and xylem vessels, and, therefore, functionality of long-distance transport. We hypothesize that changes in the plants' B nutritional status evoke differential responses of the vasculature and the mesophyll. However, direct analyses of the vasculature in response to B deficiency are lacking, due to the experimental inaccessibility of this tissue. Here, we generated biochemical and physiological understanding of B deficiency response reactions in common plantain (Plantago major L.), from which pure and intact vascular bundles can be extracted. Low soil B concentrations affected quantitative distribution patterns of various phytohormones, sugars and macro-, and micronutrients in a tissue-specific manner. Vascular sucrose levels dropped, and sucrose loading into the phloem was reduced under low B supply. Phytohormones responded selectively to B deprivation. While concentrations of abscisic acid and salicylic acid decreased at low B supply, cytokinins and brassinosteroids increased in the vasculature and the mesophyll, respectively. Our results highlight the biological necessity to analyze nutrient deficiency responses in a tissue- rather organ-specific manner.
-
7.
Ecofriendly microwave-assisted reaction and extraction of bioactive compounds from hawthorn leaf.
Hu, YH, Peng, LQ, Wang, QY, Yang, J, Dong, X, Wang, SL, Cao, J, Liu, FM
Phytochemical analysis : PCA. 2019;(6):710-719
Abstract
INTRODUCTION The main active components in hawthorn leaves possess various biological activities such as anti-inflammatory, antioxidant, and hypolipidemic effects. Therefore, it is necessary to develop an effective and reliable extraction method to extract these active compounds from hawthorn leaves. OBJECTIVE To establish a simple, rapid, and sensitive method for extraction and determination of polyphenolic compounds from hawthorn leaves. METHODS In this study, a microwave-assisted reaction and extraction (MARE) combined with ultra-high-performance liquid chromatography with ultraviolet detector method was established to extract and determine the polyphenolic compounds in hawthorn leaves. The solid reagent aqueous solutions were applied as extraction solvents, preventing the use of organic solvents. The target analytes were identified by quadrupole time-of-flight tandem mass spectrometry. Several experimental parameters that can significantly affect the extraction efficiency were evaluated and optimised. RESULTS The optimal conditions were as follows: 0.1 g of sodium carbonate was used as solid reagent, the amount of sodium borate was set at 0.01 g, extraction time was 10 min, extraction temperature was set at 50°C, pH value was adjusted to 7. The validation experiments demonstrated that the method had high sensitivity with the limits of detection in the range 26.5-37.7 ng/mL. The average recoveries ranged from 80.22% to 93.27%. CONCLUSION In this work, the proposed MARE method was successfully applied to extract and determine polyphenolic compounds in hawthorn leaf samples. Compared with other reported methods, the present method was faster, greener, and more sensitive.
-
8.
Effects of olive leaf extract addition on fermentative and oxidative processes of table olives and their nutritional properties.
Caponio, F, Difonzo, G, Calasso, M, Cosmai, L, De Angelis, M
Food research international (Ottawa, Ont.). 2019;:1306-1317
Abstract
An experimental investigation evaluated the possibility of increasing the nutritional value of fermented table olives by adding olive leaf extract (OLE). OLE was added to table olives fermented using indigenous bacteria and yeasts, and a commercial starter (Lactobacillus plantarum strain). Microbiological, physico-chemical, and sensory analyses showed that OLE addition resulted in fermented olives with higher levels of antioxidant, anti-inflammatory, and antimicrobial substances, but did not adversely affect their qualities. Moreover, OLE and the commercial starter functioned synergically against spoilage microorganisms. In addition, fermented olives had higher values of hardness, total phenols, antioxidant activity, hydroxytyrosol, and verbascoside. Nonanal and ethanol contents were lower in fermented olives when Lactobacillus plantarum and OLE were used, indicating lower degrees of oxidation and fermentation. Finally, olives fermented with OLE had a less bitter taste.
-
9.
Moringa peregrina Leaves Extracts Induce Apoptosis and Cell Cycle Arrest of Hepatocellular Carcinoma.
Mansour, M, Mohamed, MF, Elhalwagi, A, El-Itriby, HA, Shawki, HH, Abdelhamid, IA
BioMed research international. 2019;:2698570
Abstract
Moringa grows in the tropical and subtropical regions of the world. The genus Moringa belongs to family Moringaceae. It is found to possess various medicinal uses including hypoglycemic, analgesic, anti-inflammatory, hypolipidemic, and antioxidant activities. In this study, we investigated the antimicrobial and the anticancer activity of the Moringa peregrina as well as Moringa oleifera leaves extracts grown locally in Egypt. Results indicated that most of the extracts were found to possess high antimicrobial activity against gram-positive bacteria, gram-negative bacteria, and fungus. The survival rate of cancer cells was decreased in both hepatocellular carcinoma (HepG2) and breast carcinoma (MCF-7) cell lines when treated with Moringa leaves extracts. In addition, the cell cycle progression, apoptosis, and cancer-related genes confirmed its anticancer effect. The toxicity of each extract was also tested using the normal melanocytes cell line HFB4. The toxicity was low in both Moringa peregrina and Moringa oleifera leaves extracts. Furthermore, GC/MS analysis fractionized the phytochemicals content for each potential extract. In conclusion, results suggested that the Moringa peregrina and Moringa oleifera leaves extracts possess antimicrobial and anticancer properties which could be attributed to the bioactive phytochemical compounds present inside the extracts from this plant. These findings can be used to develop new drugs, especially for liver cancer chemotherapy.
-
10.
Emission level of seven mainstream smoke toxicants from cigarette with variable tobacco leaf constituents.
Cai, B, Li, Z, Wang, R, Geng, Z, Shi, Y, Xie, S, Wang, Z, Yang, Z, Ren, X
Regulatory toxicology and pharmacology : RTP. 2019;:181-188
Abstract
[Introduction] Seven smoke constituents, including hydrogen cyanide (HCN), ammonia (NH3), phenol, benzo[α]pyrene (B[a]P), carbon monoxide (CO)¸ crotonaldehyde, and 4-(methylnitrosamino)-1- (3-pyridyl)-1-butanone (NNK), are proposed be the most relevant constituents for smoking-related diseases. [Methods] Different combinations of leaf stalk positions, varieties and locations were used to create variable chemistry of cigarette filler and smoke. Experimental cigarettes were measured for emission level of seven smoke toxicants and content of seventy-three filler components. [Results] The ranges of coefficient of variation (CV) for seven smoke toxicants were 15.43%-43.15%. The emission pattern of NNK and crotonaldehyde were different from that of other five smoke toxicants. Most of the seven smoke toxicants were influenced in following order: stalk position > location > variety. The leaf constitutes closely correlated with seven smoke toxicants were analyzed. [Conclusions] The results showed that seven toxicants were significantly influenced by leaf position and location, and closely correlated with leaf components, such as potassium, malate and alkaloid contents. The results provide useful and comprehensive information on the affecting factors and correlating leaf constituents for the variations of seven smoke toxicants.