Kavalactones, mainly found in Piper methysticum, are a class of lactone compounds usually with an arylethylene-pyrone skeleton. Till now, fifty-one kavalactones have been isolated from the genera Piper, Alpinia, Amomum, Polygala, Goniothalamus, and Dumortiera. The bioactivities of six kavalactones, kawain, 7,8-dihydro- kawain, methysticin, dihydromethysticin, yangonin, and desmethoxyyagonin, have been studied extensively. This review aims to give an overview of kavalactones in the plants and their various bioactivities.
Methicillin-resistant Staphylococcus aureus (MRSA) is a multi-drug resistant pathogenic bacteria, which has seriously threatened human health for a long time. Therefore, there is an urgent and unmet demand for new types of antibiotics. In response to the antibiotic resistance, many researchers have studied natural products derived from plant for alternative antibiotics and therapies. In this review, we summarized recent advances on anti-MRSA natural products from plants and their potential antibacterial effect against MRSA as potential anti-MRSA agents since 2007.
Bioactive components of marine species have received great attention in recent years, especially phlorotannins isolated from brown algae. This paper summarized progress in the structures and bioactivities of phlorotannins including antibacterial, antioxidant, anticoagulant, anti-diabetic, anti-hypertensive, inhibiting HIV, anti-tumor, anti-allergic, anti-inflammatory, defense activity, and deodorant activities.
Thrombosis owns the highest incidence, and it is a serious threat to human health. Currently, the clinical antithrombotic drugs suffer from several drawbacks, causing allergic reactions or complications, etc. In recent years, small-molecule compounds isolated from natural products with antithrombotic activities in the field drug research on thrombus disease. In this review, we will focus on representative naturally occurring small molecule phenols with antithrombotic potency and potential for future therapeutic regimens to combat thrombosis disease.
The skin barrier is regulated by the stratum corneum and the tight junction located at the lamellar layer. Skin barrier can maintain the body’s moisture, prevent pathogens and allergens. Atopic dermatitis is caused by changes in the skin barrier associating with skin coloring. The main function of filaggrin is to maintain skin moisture. The level of filaggrin and its degradation products is affected not only by the genotype of filaggrin, but also by the inflammatory and exogenous stress factors. Regardless of the state of mutations in the filamentous protein, filaggrin deficiency was observed in patients with atopic dermatitis, indicating that the removal of polyphenol was a key factor in the pathogenesis of the skin disease. In this paper, we reviewed the function and morphological effects of filaggrin and its metabolites in the pathogenesis of atopic dermatitis. Filaggrin is considered as one of the most important proteins in the skin barrier.
Thrombosis is a serious disease of human health and life. Microorganism is an important source of fibrinolytic enzymes. The mechanism of action that it must combine with plasminogen to activate plasminogen of streptokinase is described. Herein, we summarize species characteristics and thrombolytic effects of fibrinolytic enzymes that are secreted from bacteria, actinomycetes and fungi. In recent years, more and more marine plasmin were found and used in thrombolytic test, displaying good fibrinolysis and thrombolysis.
Thrombus is a severe health problem all over the world, especially in developing countries. However, there is still no satisfactory antithrombotic therapeutic strategy. Currently, the clinical antithrombotic drugs suffer from several drawbacks such as high rate of bleedings and short half-life, causing allergic reactions or complications, etc. In recent years, small-molecule compounds isolated from natural products with antithrombotic activities become a hot issue in the field of drug research. In this review, we will focus on representative naturally occurring small molecule flavonoids with antithrombotic potency and potential for future therapeutic regimens to combat thrombosis disease.
The aim of this study was to investigate the benefits of incorporation of graphene oxide-silica (GO@SiO2) on the degree of conversion and bond strength of an experimental dental adhesive. The GO@SiO2 nanocomposites were prepared and characterized by using FTIR, Raman and TEM. After that, GO@SiO2 was added into an experimental dental bonding system as novel nanofiller, and the effect of the modification on the dispersion stability of the GO@SiO2 nanocomposites in the experimental adhesive was studied. In addition, the degree of conversion was characterized by real-time FTIR, and the light conversion kinetic curves were calculated. Furthermore, the bond strength of the experimental adhesive to dental restorative resin was investigated. The result showed that the GO@SiO2 nanocomposites dispersed well in the experimental adhesive, and the introduction of GO@SiO2 improved effectively the degree of conversion of the dental adhesive after curing. In addition, the experimental adhesive filled with GO@SiO2 nanocomposites showed not only similar bond strength to a commercial adhesive, but also enhanced dramatically compressive strength as well. Furthermore, the obtained experimental dental adhesives can increase reactive oxygen species level in cells through photothermal conversion to be used in potential therapy.
Bulleyaconitine A, a C19-diterpenoid alkaloid extracted from Aconitum bulleyanum Diels, showed various bioactivities, including anti-inflammatory, antinociceptivity, immunomodulatory effects as well as some toxicities. This paper reviewed the bioactivities of Bulleyaconitine A and the relevant mechanisms, toxicities, as well as the metabolism.
Hand, foot, and mouth disease (HFMD) has become one of the most common infectious diseases in mainland China, with annual incidence rate up to 100 per 100,000. We analyzed data reported to surveillance systems at the Chinese Center for Disease Control and Prevention and described the epidemiological features of HFMD by age, seasonal, and geographic distribution from 2011 to 2012. The annual incidence rates of 2011 and 2012 were 120.8 and 161.0 per 100,000, respectively. Most HFMD cases (approximately 90%) were aged within 0-4 years old, while older children and adults were rarely affected. Seasonal variation in incidence was observed, with an incidence peak observed during May and June. The southeastern coastal areas of China display highest incidence rates of HFMD. HFMD is a common infectious disease in China and it has emerged as an important public concern causing extensive transmission in young children.
A lot ofindole compounds possessing complex structures exist widely in alkaloids with enormous research significance. Specifically, bisindoles play a great role in the treatment of cancer, tumors, cardiovascular and cerebrovascular diseases. Many researchers are devoted to their biosynthesis. The structural diversity of bisindoles is attributed to multiple active sites of tryptophan. They presented bioactivities against anti-inflammatory, anti-bacterial, anti-virus and anti-cancer properties at the C-3 site of bisindoles. This paper reviews recent advances on biosynthesis pathways and bioactivites of bisindoles.
The walnut kernel has appeared on dining tables as a non-staple food and gained much popularity for centuries owing to its flavor as well as the function of food therapy, while the green husk or hard shells enwrapped are always discarded or processed into low value-added products. The waste of walnut green husk and shell can cause environment pollution and the waste of resources. As medicinal food, lots of researches on walnut have been carried out during the past decades, including the walnut kernel, the green husk and the hard shell. The researches on the green husk and hard shell showed the mass of chemical compounds isolated from both green husk and hard shell possesses various bioactivities such as antimicrobial, antioxidant, antitumor, and other effects. In this paper, we summarized phytochemical compositions of green husk and hard shell of walnut (Junglans regia) as well as their bioactivities.
In recent years, marine natural products isolated from associated microorganisms have become a hot topic in medicine. It has been reported that secondary metabolites produced by sponge-associated fungi are of great importance for the discovery of active substances with novel structures and they own broad prospects for clinical medicine and the development of drugs. Herein, we summarize the structures of marine sponge-associated fungi including lactones, anthraquinones, pyrenes, chromones and others, as well as the bioactivities of polyketides from marine sponge-associated fungi.
Lindera glauca is a folk medicine with rich resources in China. Previous phytochemical studies on L. glauca have resulted in the isolation and identification of the main chemical constituents such as alkaloids, sitosterol, flavonoids, sesquiterpenes, and lignans, as well as essential oil, with antimicrobial, antitumor activity and other pharmacological effects. In this paper, the chemical compositions and pharmacological effects of L. glauca were summaried.
Iron (Fe), an essential micro-nutrient for marine organisms, is a necessary element for many biochemical processes such as photosynthesis, respiration, synthesis of DNA and chlorophyll, and reduction of nitrate. However, the iron for life is in water under natural pH conditions in the main form of Fe(OH)3. The concentration of soluble iron is very low in seawater due to its insolubility. While iron is the fourth most abundant transition metal in the Earth's crust, the insolubility of iron(III) [KSp of Fe(OH)3 = 10-39] at physiological pH in aerobic environments limits the availability of this essential nutrient severely. Marine microbes face similar challenges for obtaining iron because they live in the environments with very low iron concentrations. In this paper, we summarize the detection methods of siderophores from marine microbials and their structures.
Rhodotorula benthica is a unicellular yeast strain and presents widely in ocean with rich compositions of proteins, carotenoids, vitamins, digestive enzymes, and other biologically active substances. It has been applied in many fields including food, feed, medicine, and water industry. Rhodotorula species grow rapidly at 30 ℃ with coral pink, smooth, and moist to mucoid fettle, while the growth at 37 ℃ is variable. Rhodotorula species are strict aerobic yeasts with peculiarly metabolic characteristics. Rhodotorula produces urease and it has the inability to assimilate inositol and ferment sugars. Moreover, it is well known as a good source of carotenoids, proteins, essential amino-acids, digestive enzymes, lipids and vitamins. Rhodotorula benthica possesses a broad utilization prospect based on its metabolites, structures and bioactivities. This review summarizes some advances on the types, structures, and biological applications of the isolates from Rhodotorula glutinis.
As cancer is one of humanity’s biggest killers in the world, scientists have been looking for different drugs as agents to treat cancer. However, current chemotherapeutics is not sufficiently effective. Thiosemicarbazone complexes of transition metals have attracted wide attention due to a great effect of anticancer activity with different mechanisms including ribonucleotide reductase inhibition, metal dependent radical damage, DNA binding, and inhibition of protein synthesis, and so on. In this minireview, we summarize different metal chelators of thiosemicarbazones and their anticancer mechanisms, which are useful for the development of thiosemicarbazone as anticancer drugs.
Ultrasound-mediated gene delivery is a kind of new method of gene delivery because ultrasound given a certain dose of irradiation can reversibly change the morphology of the cell membrane. Thus, a gene carrier material is obtained through a positive liposome filled with CO2 gas and absorbed by DNA molecule, in which ultrasound-mediated gene delivery is established. Furthermore, the kind of new method of gene delivery is helpful for the dissociation of DNA molecules from liposome (LIP)/DNA complex and the cellular membrane permeability, which can increase SPCA-1 cell viability. Furthermore, the transfection efficiencies of LIP/DNA complex to cells are performed and the effect of ultrasonic time and intensity is further estimated.
Poly(lactic-co-glycolic acid) (PLGA)-block-polyethylene glycol (PEG)/perfluoroctyl bromide (PFOB) emulsion, in which PLGA-block-PEG, as the carrier, is combined with perfluorocty bromide, is developed to improve arterial hypoxemia and ameliorate the lung ventilation through pulmonary drug delivery. The cell viability increased obviously, which shows that the emulsion has certain positive effects on the cell proliferation. Moreover, the emulsion can help cells quickly recover from the anoxic symptoms as indicated by cell hypoxia-reoxygenation experiment. When cells were incubated with the emulsion under hypoxia, an obvious increase of cell growth was observed, which indicated that the emulsion was capable of providing sufficient oxygen for cells. Then we established two different models of rabbits to investigate whether the PLGA-b-PEG/PFOB emulsion could improve lung ventilation of animals. The impressive result confirmed that the lung ventilation was ameliorated significantly after treatment of emulsion for a period of time. The histological assays further verified the emulsion had good biocompatibility. Furthermore, the concentration of HIF-1 alpha in tissues were evaluated by immunohistochemistry and western respectively to confirm the fact that the emulsion could significantly promote the expression of HIF-1 alpha in lung tissue cells which may have important contributions to tissue survival. In summary, the emulsion was confirmed to supply oxygen for cells and organisms to improve arterial hypoxemia, which reflects the tremendous potential application value in the field of alleviating hypoxemia in future.