Evaluation of chemopreventive and cytotoxic effect of lemon seed extracts on human breast cancer (MCF-7) cells

Plant and mammalian-derived extracellular vesicles: a new therapeutic approach for the future

Background: In recent years, extracellular vesicles have been recognized as important mediators of intercellular communication through the transfer of active biomolecules (proteins, lipids, and nucleic acids) across the plant and animal kingdoms and have considerable roles in several physiological and pathological mechanisms, showing great promise as new therapeutic strategies for a variety of pathologies. Methods: In this study, we carefully reviewed the numerous articles published over the last few decades on the general knowledge of extracellular vesicles, their application in the therapy of various pathologies, and their prospects as an approach for the future. Results: The recent discovery and characterization of extracellular vesicles (EVs) of diverse origins and biogenesis have altered the current paradigm of intercellular communication, opening up new diagnostic and therapeutic perspectives. Research into these EVs released by plant and mammalian cells has revealed their involvement in a number of physiological and pathological mechanisms, such as embryonic development, immune response, tissue regeneration, and cancer. They are also being studied as potential biomarkers for disease diagnosis and vectors for drug delivery. Conclusion: Nanovesicles represent powerful tools for intercellular communication and the transfer of bioactive molecules. Their molecular composition and functions can vary according to their origin (plant and mammalian), so their formation, composition, and biological roles open the way to therapeutic applications in a variety of pathologies, which is arousing growing interest in the scientific community. Clinical Trial Registration: ClinicalTrials.gov identifier: NCT03608631.

Antioxidant Activity and Chemical Composition of Geranium Oil and Its Synergistic Potential against Pneumococci with Various Antibiotic Combinations

The essential oil of Pelargonium graveolens L. is valuable for its therapeutic benefits, so this study aimed to determine the synergistic effect of the combination of the essential oil of this plant with antibiotics instead of the extracts prepared with various solvents. In addition, the second goal of this study was to determine whether the essential oil combined with various antibiotics increased the overall killing activity in mouse macrophage cells with the aim of introducing an immunotherapeutic approach to the infection treatments used today. Herein, the volatile profile of Geranium oil (G.O) was analyzed using GC/MS. The current study sought to assess the synergistic characteristics of several antibiotic combinations using G.O against pneumococci, as well as the oil's antioxidant and antimicrobial activities. The major components of the oil were citronellol, geraniol, and isomenthone. In the combinations of G.O and antibiotics, the synergism of the Streptococcus pneumoniae to antibiotics advanced. When the time-kill data were evaluated, G.O + antibiotic combinations quickly diminished the viable cell count of S. pneumoniae from the 6th h. In this study, the combined use of existing antibiotics used in infection treatments with G.O could improve antibiotic effectiveness and thus prevent bacteria from developing antibiotic resistance.

Impact Assessment of Lead-Tolerant Rhizobacteria to Improve Soil Health Using Indian Mustard (Brassica juncea) as an Indicator Plant

Due to ongoing human activities, heavy metals are heavily accumulated in the soil. This leads to an increase in the discharge and the quick spread of heavy metal pollution in human settlements and natural habitats, having a disastrous effect on agricultural products. The current experiment was planned to evaluate the effect of lead-tolerant-plant-growth-promoting rhizobacteria (LTPGPR) on growth, yield, antioxidant activities, physiology, and lead uptake in the root, shoot, and seed of Indian mustard (Brassica juncea) in lead-amended soil. Three pre-isolated well-characterized lead-tolerant rhizobacterial strains-S10, S5, and S2-were used to inoculate seeds of Indian mustard grown at three different levels of lead (300 mg kg-1, 600 mg kg-1, 900 mg kg-1) contaminated soil. The experiment was designed following a completely randomized design (CRD) under factorial arrangements. Lead nitrate was used as a source of lead contamination. At harvesting, data regarding growth, physiology, yield per plant, antioxidant activities, malondialdehyde and proline content, and lead uptake in the root, shoot, and seed of Indian mustard were recorded. Results demonstrated that lead contamination at all levels significantly reduced the plant growth, yield, and physiological processes. Plants inoculated with lead-tolerant rhizobacteria showed a significant improvement in plant growth, yield, antioxidant activities, and physiological attributes and cause a valuable reduction in the malondialdehyde contents of Indian mustard in lead-contaminated soil. Moreover, plants inoculated with lead-tolerant rhizobacteria also showed an increment in lead uptake in the vegetative parts and a significant reduction of lead contents in the seed of Indian mustard.

Anticancer Potential of Hesperidin against HEp-2 Laryngeal Carcinoma Cell Line in Comparison to Doxorubicin

BACKGROUND: Doxorubicin (DOX) is a drug that is frequently used to treat a variety of cancers. Unfortunately, in many situations, it is ineffective, and raising the dosage is restricted due to systemic toxicity. An important strategy to minimize the toxic effects of the above cited drug is to use co-adjuvant. A citrus flavonoid hesperidin (Hesp) has emerged as promising anticancer natural product and proved to be potent antioxidant agent. It suppresses cancer cell replicating by triggering apoptosis and cell cycle arrest. AIM: The study’s goal was to investigate anticarcinogenic effects of Hesp in comparison with DOX against HEp-2 laryngeal carcinoma cell line. MATERIALS AND METHODS: Five groups of HEp-2 cell line were included, two groups were subjected to Hesp and the other two groups were subjected to DOX, which was used as a reference drug, in addition to a control untreated group. Expression of Bcl-2 and p53 genes was evaluated. Furthermore, the cell cycle arrest and apoptotic induction were assessed. RESULTS: Hesp exerted anti-proliferative effects against HEp-2 cells which increase in time dependent manner. Gene profile analysis revealed highly statistically significant decrease of anti-apoptotic Bcl-2 expression and highly statistically significant increase of tumor suppressor gene p53 expression (p ˂ 0.01 and p ˂ 0.0001, respectively) for both tested drugs. CONCLUSIONS: Hesp proved potential anticancer effects with reducing cancer cell viability in HEp-2 cell line through cell cycle arrest and apoptotic mechanism. It could be used as a prodrug or coadjuvant in treatment of oral cancer.

Virtual screenings of the bioactive constituents of tea, prickly chaff, catechu, lemon, black pepper, and synthetic compounds with the main protease (Mpro) and human angiotensin-converting enzyme 2 (ACE 2) of SARS-CoV-2

Background

COVID-19 has mutation capability, and there are no specific drug therapies that are available to fight or inhibit the proteins of this virus. The present study aims to investigate the binding affinity of the bioactive and synthetic compounds with the main protease (Mpro) enzymes and angiotensin-converting enzyme 2 (ACE 2) by computational approach. PASS prediction, pharmacokinetics, and toxicological properties prediction studies were performed through the Google PASS prediction and Swiss ADME/T website. Besides, molecular docking studies were accomplished by BIOVIA Discovery Studio 2020, UCSF Chimera, and PyRx autodock vina.

Results

The docking scores were inferred and the selected compounds showed results varying from −3.2 to −9.8 (kcal/mol). Theaflavin scored the highest docking score to the 5REB, 6VW1, and 1R42 enzymes and showed the binding affinity as −6.3 kcal/mol, −9.8 kcal/mol, and −8.6 kcal/mol, respectively. Again, kaempferol showed the best binding affinity to the 7BQY (−7.1 kcal/mol) and 6Y2FB (−6.6 kcal/mol) enzymes. All the chemical constituents showed better probability in action in pass prediction analysis. Besides, no ligands (except theaflavin) have any conflict with Lipinski’s rules of five, which authorized the drug probability of these ligands.

Conclusion

Therefore, the selected compounds could be considered a potential herbal treatment source against SARS-CoV-2.

Effects of plants extracts on the expression of major genes of JAK/STAT pathway

This study analyzed the effects of the plant extracts (Citrus limon, Solanum lycopersicum, Zingiber officinale, Vitis vinifera and Allium sativum) on the growth of mammalian cells (Vero and MDA-MB-231) and evaluated the most effective plant extract for the expression of specific genes of the JAK/STAT pathway in human breast cancer cells. An antiproliferative bioassay involving neutral red-dye uptake was used to determine the anticancerous potential of plant extracts. In Vero cells, the ginger methanolic extract was least effective; whereas the lemon methanolic extract was more effective with 64 dilutions with IC₅₀ 51.42%. In MDA-MB-231 cells, the tomato and ginger methanolic, and grape water extracts were least effective, whereas lemon water extract was most effective with 32 dilutions with IC₅₀ 48.67%, by upregulating JAK1, JAK2, TYK2, IRF7 and IRF3 gene expressions of the JAK/STAT pathway. C. limon inhibited the growth of both Vero and MDA-MB 231 cells. It suggested that C. limon has anti-cancer potential by inducing the JAK/STAT pathway.

Valorization and extraction optimization of Citrus seeds for food and functional food applications

Valorization of food byproducts has attracted recently considerable attention. Citrus fruits provide considerable non-edible residues reach 80% in juice production. They are considered agri-wastes to comprise peel, pulp and seeds. Previous investigations have focused on peel and pulp to recover value-added products. The review presents for the first-time phytochemical composition of Citrus seeds' products, i.e., oil and extracts. Fatty acids, phytosterols and tocopherols amounted as the major bioactives in Citrus seeds, in addition to limonoids, dietary fibers and flavonoids. Besides their nutritional values, these chemicals have promising applications including production of biodiesel, food enhancers and antioxidants, especially from mandarin and grapefruit seeds. Optimum conditions of the different Citrus seeds' valorization are discussed to improve extraction yield and lessen environmental hazards of solvent extraction. This review presents the best utilization practices for one of the largest cultivated fruit seeds worldwide and its different applications.

Improvement of Flavonoids in Lemon Seeds on Oxidative Damage of Human Embryonic Kidney 293T Cells Induced by H2O2

In this study, flavonoids in lemon seeds (FLS) were used to assess its improvement on the oxidative damage of human embryonic kidney 293T cells (HEK 293T cells) induced by H₂O₂. In vitro experiments showed that the survival rates of HEK 293T cells treated with different flavonoid concentrations (50 μg/mL, 100 μg/mL, and 150 μg/mL) exceeded 95%, indicating no significant toxic effect. Compared with the normal group, H₂O₂ (0.3 mmol/L) resulted significantly in oxidative stress injury of HEK 293T cells. The survival rate of the damaged cells increased after treatment with flavonoids, and the survival rate of cells treated with a high concentration (150 μg/mL) of flavonoids was 76.2%. Flavonoids also effectively inhibited H₂O₂-induced apoptosis. At the same time, flavonoid treatment significantly reduced the malondialdehyde content in cells and increased the levels of catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px). Quantitative polymerase chain reaction (qPCR) and Western blot analysis also suggested that FLS upregulated mRNA and protein expressions of CAT, SOD (SOD1, SOD2), GSH (GSH1), and GSH-Px in H₂O₂-induced oxidative damage of HEK 293T cells. The high-performance liquid chromatography analysis demonstrated that FLS contained six compounds, including gallocatechin, caffeic acid, epicatechin, vitexin, quercetin, and hesperidin. FLS were proven to have a good antioxidant capacity in vitro and improve significantly the oxidative damage of HEK 293T cells induced by H₂O₂. The biological activity value warrants investigation in additional studies.

Citrus limon (Lemon) Phenomenon-A Review of the Chemistry, Pharmacological Properties, Applications in the Modern Pharmaceutical, Food, and Cosmetics Industries, and Biotechnological Studies

This review presents important botanical, chemical and pharmacological characteristics of Citrus limon (lemon)—a species with valuable pharmaceutical, cosmetic and culinary (healthy food) properties. A short description of the genus Citrus is followed by information on the chemical composition, metabolomic studies and biological activities of the main raw materials obtained from C. limon (fruit extract, juice, essential oil). The valuable biological activity of C. limon is determined by its high content of phenolic compounds, mainly flavonoids (e.g., diosmin, hesperidin, limocitrin) and phenolic acids (e.g., ferulic, synapic, p-hydroxybenzoic acids). The essential oil is rich in bioactive monoterpenoids such as D-limonene, β-pinene, γ-terpinene. Recently scientifically proven therapeutic activities of C. limon include anti-inflammatory, antimicrobial, anticancer and antiparasitic activities. The review pays particular attention, with references to published scientific research, to the use of C. limon in the food industry and cosmetology. It also addresses the safety of use and potential phototoxicity of the raw materials. Lastly, the review emphasizes the significance of biotechnological studies on C. limon.

Duchesnea indica extract attenuates oral cancer cells metastatic potential through the inhibition of the matrix metalloproteinase-2 activity by down-regulating the MEK/ERK pathway

BACKGROUND

Duchesnea indica (Andr.) Focke, an herb in folk medicine used extensively in traditional Chinese medicine, has cytostatic properties as well as antioxidant and antimetastasis activities in various cancer cells. However, the effects and underlying mechanisms of Duchesnea indica extracts (DIEs) on human oral squamous cell carcinoma (OSCC) metastases remain unclear.

PURPOSE

In this study, we posit the hypothesis that DIE possesses antimetastatic effects on human OSCC cells.

METHODS

The effects of DIE on cell viability, motility, migration, and invasion were investigated. Gelatin zymography, Western blotting, migration and invasion assays were used to further study the underlying mechanisms involved in the antimetastatic effects of DIE in OSCC cells.

RESULTS

The results from MTT assay revealed that DIE did not affect the cell viability of OSCC cells. Moreover, DIE significantly attenuated OSCC cells' motility, migration, and invasion by reducing the MMP-2 protein expression and MMP-2 activity in a dose-dependent manner. In addition, DIE reduced the phosphorylation of both ERK1/2 and its upstream kinase but had no effect on the phosphorylation of p38 and JNK.

CONCLUSION

DIE triggers the antimetastatic activity in OSCC cells by suppressing the MMP-2 activity via the MEK/ERK signaling pathways. Therefore, these findings are promising for the use of DIE antimetastatic activity in oral cancer metastasis treatment.

Citrus nomilin down-regulates TNF-α-induced proliferation of aortic smooth muscle cells via apoptosis and inhibition of IκB

Nomilin is a bitter compound present in citrus and has been demonstrated as useful for various disease preventions through anti-proliferative, anti-inflammatory, and pro-apoptotic activities. Although in vitro disease models have shown that certain limonoids in the p38 mitogen-activated protein kinase signal cascade, the downstream signaling pathways remain unclear. In this study, the effects of nomilin on the proliferation and apoptotic pathways of human aortic smooth muscle cells (HASMCs) that forms the basis of progression of atherosclerotic diseases and restenosis was tested for the first time. The cellular uptake level and stability of nomilin were determined by high-performance liquid chromatography and high-resolution mass spectra. Pretreatment of HASMCs with nomilin stimulated extrinsic caspase-8, intrinsic caspase-9, and apoptotic caspase-3 and resulted in significant inhibition of TNF-α-induced proliferation. Additionally, results showed a decreased ratio of anti-apoptotic Bcl-2 protein to pro-apoptotic Bax (Bcl2/Bax), indicating mitochondrial dysfunction consistent with apoptosis. Furthermore, nomilin significantly decreased the phosphorylation of IκBα, an inhibitor of NF-κB and subsequently, reduced the downstream inflammatory signaling in TNF-α treated HASMCs. Our findings indicate that the anti-proliferative activity of nomilin on TNF-α-induced HASMCs results from apoptosis through a mitochondrial-dependent pathway and suppression of inflammatory signaling mediated through NF-κB.

Duchesnea indica extract suppresses the migration of human lung adenocarcinoma cells by inhibiting epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) is a process through which epithelial cells are transformed into mesenchymal cells; EMT diminishes cell polarity and cell-cell adhesion in cancer cells, leading to enhanced migratory and invasive properties. In this experiment, zymography, cell invasion, and migration assays were performed. Results indicated that Duchesnea indica extracts (DIE) inhibited highly metastatic A549 and H1299 cells by reducing the secretions of matrix metalloproteinase-2 and urokinase-type plasminogen activator. Cell adhesion assay also demonstrated that DIE reduced the cell adhesion properties. Western blot analysis showed that DIE down-regulated the expression of N-cadherin, fibronectin, and vimentin, which are mesenchymal markers, and enhanced that of E-cadherin, which is an epithelial marker. In vivo study showed that tumor growth was significantly reduced in BALB/c nude mouse xenograft model administered with oral gavage of DIE. Therefore, DIE could be exhibits potential as a phytochemical-based platform for prevention and treatment of lung cancer. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 2053-2063, 2017.

The Chemistry and Pharmacology of Citrus Limonoids

Citrus limonoids (CLs) are a group of highly oxygenated terpenoid secondary metabolites found mostly in the seeds, fruits and peel tissues of citrus fruits such as lemons, limes, oranges, pumellos, grapefruits, bergamots, and mandarins. Represented by limonin, the aglycones and glycosides of CLs have shown to display numerous pharmacological activities including anticancer, antimicrobial, antioxidant, antidiabetic and insecticidal among others. In this review, the chemistry and pharmacology of CLs are systematically scrutinised through the use of medicinal chemistry tools and structure-activity relationship approach. Synthetic derivatives and other structurally-related limonoids from other sources are include in the analysis. With the focus on literature in the past decade, the chemical classification of CLs, their physico-chemical properties as drugs, their biosynthesis and enzymatic modifications, possible ways of enhancing their biological activities through structural modifications, their ligand efficiency metrics and systematic graphical radar plot analysis to assess their developability as drugs are among those discussed in detail.

Chemopreventive Agents and Inhibitors of Cancer Hallmarks: May Citrus Offer New Perspectives?

Fruits and vegetables have long been recognized as potentially important in the prevention of cancer risk. Thus, scientific interest in nutrition and cancer has grown over time, as shown by increasing number of experimental studies about the relationship between diet and cancer development. This review attempts to provide an insight into the anti-cancer effects of Citrus fruits, with a focus on their bioactive compounds, elucidating the main cellular and molecular mechanisms through which they may protect against cancer. Scientific literature was selected for this review with the aim of collecting the relevant experimental evidence for the anti-cancer effects of Citrus fruits and their flavonoids. The findings discussed in this review strongly support their potential as anti-cancer agents, and may represent a scientific basis to develop nutraceuticals, food supplements, or complementary and alternative drugs in a context of a multi-target pharmacological strategy in the oncology.

Bioactives in cactus (Opuntia ficus-indica) stems possess potent antioxidant and pro-apoptotic activities through COX-2 involvement

BACKGROUND

Bioactives extracted from cactus (Opuntia ficus-indica) stems were investigated for their chemopreventive activities using human cancer cells in vitro. The bioactives present in crude extracts were detected and quantified using high-performance liquid chromatography.

RESULTS

Among all the extracts, such as hexane, ethyl acetate (EtOAc), acetone, methanol (MeOH), and MeOH:water (80:20), the MeOH extract had the highest amount of polyphenolic compounds and the acetone extract exhibited the most potent effect at scavenging the 2,2,-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS(•+) ) radical. In addition, most of the extracts, with the exception of hexane, exhibited significant cytotoxicity in human SW480 colon and MCF7 breast cancer cells. Overall, the SW480 cells were more sensitive than the MCF7 cells to the cytotoxic effect of the O. ficus-indica extracts (OFEs). Cell death by OFE treatment caused significant inhibition of cyclooxygenase-2 and increased the Bax/Bcl2 ratio in both SW480 and MCF7 cell lines. However, degradation of poly (ADP-ribose) polymerase was significantly increased by OFE only in the MCF7 cells, thereby inducing apoptosis.

CONCLUSION

These findings demonstrate the health-benefit roles, including anti-oxidative and anti-proliferative activities as well as pro-apoptotic effects, of bioactive compounds in OFEs, suggesting a chemopreventive role in human cancer cells.

Polymethoxyflavones Isolated from the Peel of Miaray Mandarin (Citrus miaray) Have Biofilm Inhibitory Activity in Vibrio harveyi

Citrus fruits are a good source of bioactive compounds with numerous beneficial biological activities. In the present study, fruits of the unexplored Miaray mandarin were used for the isolation of 10 bioactive compounds. Dried peels were sequentially extracted with hexane and chloroform in a Soxhlet-type apparatus for 8 h. The extracts were concentrated under vacuum and separated by flash chromatography to obtain nine polymethoxyflavones and a limonoid. The purity of each compound was analyzed by high-performance liquid chromatography (HPLC), and the compounds were identified by spectral analysis using MALDI-TOF-MS and NMR. The isolated compounds were identified as 5-hydroxy-3,7,3',4'-tetramethoxyflavone, 5,6,7,8,4'-pentamethoxyflavone (tangeretin), 3,5,6,7,8,3',4'-heptamethoxyflavone, 5,6,7,8,3',4'-hexamethoxyflavone (nobiletin), 3,5,7,8,3',4'-hexamethoxyflavone, 3,5,7,3',4'-pentamethoxyflavone (pentamethylquercetin), 5,7,4'-trimethoxyflavone, 5,7,8,4'-tetramethoxyflavone, 5,7,8,3',4'-pentamethoxyflavone, and limonin. These compounds were further tested for their ability to inhibit cell-cell signaling and biofilm formation in Vibrio harveyi. Among the evaluated polymethoxyflavones, 3,5,6,7,8,3',4'-heptamethoxyflavone and 3,5,7,8,3',4'-hexamethoxyflavone inhibited autoinducer-mediated cell-cell signaling and biofilm formation. These results suggest that Miaray mandarin fruits are a good source of polymethoxyflavones. This is the first report on the isolation of bioactive compounds from Miaray mandarin and evaluation of their biofilm inhibitory activity as well as isolation of pentamethylquercetin from the Citrus genus.

Hesperidin from Citrus seed induces human hepatocellular carcinoma HepG2 cell apoptosis via both mitochondrial and death receptor pathways

Citrus seeds are full of phenolic compounds, such as flavonoids. The aims of this study were to identify the types of flavonoids in Citrus seed extracts, the cytotoxic effect, mode of cell death, and signaling pathway in human hepatic cancer HepG2 cells. The flavonoids contain anticancer, free radical scavenging, and antioxidant activities. Neohesperidin, hesperidin, and naringin, active flavanone glycosides, were identified in Citrus seed extract. The cytotoxic effect of three compounds was in a dose-dependent manner, and IC50 levels were determined. The sensitivity of human HepG2 cells was as follows: hesperidin > naringin > neohesperidin > naringenin. Hesperidin induced HepG2 cells to undergo apoptosis in a dose-dependent manner as evidenced by the externalization of phosphatidylserine and determined by annexin V-fluorescein isothiocyanate and propidium iodide staining using flow cytometry. Hesperidin did not induce the generation of reactive oxygen species, which was determined by using 2',7'-dichlorohydrofluorescein diacetate and flow cytometry method. The number of hesperidin-treated HepG2 cells with the loss of mitochondrial transmembrane potential increased concentration dependently, using 3,3'-dihexyloxacarbocyanine iodide employing flow cytometry. Caspase-9, -8, and -3 activities were activated and increased in hesperidin-treated HepG2 cells. Bcl-xL protein was downregulated whereas Bax, Bak, and tBid protein levels were upregulated after treatment with hesperidin in a dose-dependent manner. In conclusion, the bioflavanone from Citrus seeds, hesperidin, induced human HepG2 cell apoptosis via mitochondrial pathway and death receptor pathway. Citrus seed flavonoids are beneficial and can be developed as anticancer drug or food supplement, which still needs further in vivo investigation in animals and human beings.

Influence of modified atmosphere packaging on 'Star Ruby' grapefruit phytochemicals

Modified atmosphere packaging (MAP) can extend the shelf life of salads, vegetables, and fruits by generating a storage environment with low O2, high CO2, and high humidity. The current study investigates the effect of modified atmosphere and humidity generated by two plastic films, microperforated bags (MIPBs) and macroperforated bags (MAPBs), on the levels of phytochemicals present in 'Star Ruby' grapefruits (Citrus paradisi, Macf.) stored for 16 weeks at 10 °C. Control fruits were stored without any packaging film. Juice samples were analyzed every 4 weeks for ascorbic acid, carotenoids, limonoids, flavonoids, and furocoumarins and assessed for quality parameters. MAP significantly reduced weight loss compared to control grapefruits. Control fruits had more β-carotene, lycopene, and furocoumarin compared with the fruits in MAP. Flavonoid content was highest in fruits stored in MAPB (P < 0.05), while fruits stored in MIPB showed no significant difference in flavonoid content compared to control (P > 0.05). The MAP treatments did not significantly affect ascorbic acid, limonoids, or fruit quality parameters, including total soluble solids, acidity, ripening ratio, decay and disorders, fruit taste, and off-flavors after 16 weeks of storage. These results suggest that MAP can be used to maintain the quality of 'Star Ruby' grapefruit with no detrimental effect on health-promoting phytochemicals.

Antioxidant activities and contents of flavonoids and phenolic acids of Talinum triangulare extracts and their immunomodulatory effects

In this study, leaves and stems of Talinum triangulare were sequentially extracted with phosphate buffer solution to obtain PTL and PTS (phosphate buffered extracts of T. triangulare leaves and stems), with 75% ethanol to obtained ETL and ETS (ethanol extracts of T. triangulare leaves and stems), or with 90°C boiling water to obtain WTL and WTS (water extracts of T. triangulare leaves and stems). We investigated the antioxidant activities of various T. triangulare extracts, analyzed the extracts’ stimulations on human mononuclear cell (MNC) growth and secretion of cytokines (interleukin-1 beta, interferon-γ, and tumor necrosis factor-α) and nitric oxide, and then assayed their subsequent inhibitions on human leukemic U937 cell growth. Results indicated that extracts of T. triangulare showed significant antioxidant activities. Among these extracts, WTS showed the highest stimulatory effect on human MNC growth. The secretion levels of interleukin-1 beta, interferon-γ, and tumor necrosis factor-α in the conditioned medium, wherein human MNC was treated with 500 μg/mL WTS for 72 hours, were 1275, 859, and 2222 pg/mL, respectively. All conditioned media obtained from human MNCs cultured with various T. triangulare extracts showed significant inhibition against U937 cell growth of over 40%. These results suggest that T. triangulare extracts may be used in health foods for their immunomodulatory potential.

Evaluation of Physiological Activities of the Citron (Citrus junos Sieb. ex TANAKA) Seed Extracts

Citron seed extracts (CSEs) were made using distilled water (CSEW), ethanol (CSEE), and n-hexane (CSEH), to measure the total polyphenol contents, DPPH and ABTS radical scavenging activities, and anti-complementary activity. The total polyphenol content was observed the highest in CSEE (188.71 μg/mL), and occurred in the following order: CSEE>CSEW (141.11 μg/mL)>CSEH (26.19 μg/mL) at 10 mg/mL. CSEE (63.56%) and CSEW (56.61%) showed significantly higher DPPH radical scavenging activities when compared with CSEH (28.57%). ABTS radical scavenging activities of CSEE (45.53%) and CSEW (40.02%) were also observed to be higher, whereas CSEH did not show ABTS radical scavenging activity. Anti-complementary activity of CSEE (26.85%) showed a greater activity than that of CSEW (7.84%) at 1,000 μg/mL. Limonin and nomilin contents had the highest values (1.882% and 2.089%) in CSEE, and with 0.327% and 0.139% in CSEW; however, CSEH showed relatively very low values at 0.061% and 0.026%, respectively. Among the CSEs tested, CSEE as a by-product from citron may provide an important source of dietary antioxidant compounds with rich polyphenol and limonoid contents, and immunopotentiating activity, including the complement activation factor.

Rubus idaeus L. reverses epithelial-to-mesenchymal transition and suppresses cell invasion and protease activities by targeting ERK1/2 and FAK pathways in human lung cancer cells

Epithelial to mesenchymal transition (EMT) has been considered essential for cancer metastasis, a multistep complicated process including local invasion, intravasation, extravasation, and proliferation at distant sites. Herein we provided molecular evidence associated with the antimetastatic effect of Rubus idaeus L. extracts (RIE) by showing a nearly complete inhibition on the invasion (p<0.001) of highly metastatic A549 cells via reduced activities of matrix metalloproteinase-2 (MMP-2) and urokinasetype plasminogen activator (u-PA). We performed Western blot to find that RIE could induce up-regulation of epithelial marker such as E-cadherin and α-catenin and inhibit the mesenchymal markers such as N-cadherin, fibronectin, snail-1, and vimentin. Selective snail-1 inhibition by snail-1-specific-siRNA also showed increased E-cadherin expression in A549 cells suggesting a possible involvement of snail-1 inhibition in RIE-caused increase in E-cadherin level. RIE also inhibited p-FAK, p-paxillin and AP-1 by Western blot analysis, indicating the anti-EMT effect of RIE in human lung carcinoma. Importantly, an in vivo BALB/c nude mice xenograft model showed that RIE treatment reduced tumor growth by oral gavage, and RIE represent promising candidates for future phytochemical-based mechanistic pathway-targeted cancer prevention strategies.

Methyl nomilinate from citrus can modulate cell cycle regulators to induce cytotoxicity in human colon cancer (SW480) cells in vitro

Limonoids are triterpenoids found in citrus and possess cancer preventive properties in in vitro and in vivo assays. Although several mechanisms for the chemopreventive properties of limonoids have been postulated, the specific mechanisms involved in the anti-cancer effects have not been explored. In the present study, limonoids, including methyl nomilinate, isoobacunoic acid, isolimonexic acid (ILNA), and limonexic acid (LNA), were purified, identified by LC-MS and NMR spectral data and evaluated for their biological effects on SW480 human colon adenocarcinoma cells. Methyl nomilinate was the most potent inhibitor of cell metabolic activity in MTT and EdU incorporation assays. These limonoids did not affect apoptotic markers such as caspase-3 and PARP, but methyl nomilinate treatment resulted in significant induction of G0/G1 cell cycle arrest. Furthermore, methyl nomilinate suppressed CDK4/6 and cyclin D3 and the expression of CDK inhibitors. Taken together, the results suggest inhibition of cell proliferation by methyl nomilinate occurs due to G1 cell cycle arrest, indicating that methyl nomilinate has potential as a chemopreventive agent.

Variation of antioxidant activity and the levels of bioactive compounds in lipophilic and hydrophilic extracts from hot pepper (Capsicum spp.) cultivars

Peppers (Capsicum spp.) are a rich source of diverse bioactive compounds with potential health-promoting properties. This study investigated the extraction efficiency of five solvents on antioxidant activities from cayenne (CA408 and Mesilla), jalapeño (Ixtapa) and serrano (Tuxtlas) pepper cultivars. Freeze-dried peppers were extracted using a Soxhlet extractor with five solvents: hexane, ethyl acetate, acetone, methanol, and methanol:water (80:20). The levels of specific bioactive compounds (phenolics, capsaicinoids, carotenoids and flavonoids) were determined by HPLC and antioxidant activities were assayed by three methods. For all pepper cultivars tested, hexane extracts had the highest levels of capsaicinoids and carotenoids, but methanol extracts had the maximum levels of flavonoids. Hexane extracts showed higher 2,2-diphenyl-1-pricrylhydrozyl (DPPH) radical-scavenging activity and higher reducing power, and acetone extracts (from Mesilla pepper) had a high reducing power. All pepper extracts, except hexane, were effective in preventing deoxyribose degradation, and the inhibition was increased by high concentrations of extracts. The results of the present study indicated that, among the different measures of antioxidant activity, DPPH radical-scavenging activity was strongly correlated with total bioactive compounds (capsaicinoids, carotenoids, flavonoids and total phenolics) in pepper cultivars.