Phytochemical Properties and In Vitro Biological Activities of Phenolic Compounds from Flower of Clitoria ternatea L.

Phenolic compounds from the flower of Clitoria ternatea L. (PCFCTL) were extracted using a high-speed shearing extraction technique and purified by AB-8 macroporous resins, and the phytochemical composition of the purified phenolic compounds from the flower of Clitoria ternatea L. (PPCFCTL) was then analyzed. Subsequently, its bioactivities including antioxidant properties, enzyme inhibitory activities, and antiproliferative activities against several tumor cell lines were evaluated. Results indicated that the contents of total phenolics, flavonoids, flavonols, flavanols, and phenolic acids in PPCFCTL were increased by 3.29, 4.11, 2.74, 2.43, and 2.96-fold, respectively, compared with those before being purified by AB-8 macroporous resins. The results showed PPCFCTL have significant antioxidant ability (measured by reducing power, RP, and ferric reducing antioxidant power method, FRAP) and good DPPH, ABTS+, and superoxide anion radical scavenging activities. They can also significantly inhibit lipase, α-amylase, and α-glucosidase. In addition, morphological changes of HeLa, HepG2, and NCI-H460 tumor cells demonstrated the superior antitumor performance of PPCFCTL. However, the acetylcholinesterase inhibitory activity was relatively weak. These findings suggest that PPCFCTL have important potential as natural antioxidant, antilipidemic, anti-glycemic and antineoplastic agents in health-promoting foods.

Extraction and purification of total flavonoids from Eupatorium lindleyanum DC. and evaluation of their antioxidant and enzyme inhibitory activities.

The health benefits and promising medical treatment potential of total flavonoids from Eupatorium lindleyanum DC. (TFELDC) have been recognized. The process parameters of extracting total flavonoids from Eupatorium lindleyanum DC. by ultrasonic-microwave synergistic extraction (UMSE) were optimized, and they were purified by AB-8 macroporous resin in the current study. In addition, the antioxidant and enzyme inhibitory activities of the purified TFELDC (PTFELDC) were evaluated. The results showed that the optimal parameters of UMSE were as follows: ethanol volume fraction 71.5%, L/S ratio 12.2 ml/g, microwave power 318 W, and extraction time 143 s. After TFELDC were purified by AB-8 macroporous resin, the total flavonoid contents of PTFELDC increased from 208.18 ± 1.60 to 511.19 ± 3.21 mg RE/g FDS. Compared with TFELDC, the content of total flavonoids in PTFELDC was increased by 2.46 times. The antioxidant activities of PTFELDC were assessed using DPPH radical, superoxide anion radical, reducing power, and ferric reducing antioxidant power assays, and the IC50 values were found to be 37.13, 19.62, 81.22, and 24.72 µg/ml, respectively. The enzyme inhibitory activities of PTFELDC were measured using lipase, α-amylase, α-glucosidase, and acetylcholinesterase assays with the IC50 values 1.38, 2.08, 1.63, and 0.58 mg/ml, respectively. By comparing with their positive controls, it was found that PTFELDC had good antioxidant activities, and lipase, α-amylase, and α-glucosidase inhibitory activities, However, the acetylcholinesterase inhibitory activity was relatively weaker. These results suggested that PTFELDC have a promising potential as natural antioxidant, antilipidemic, and hypoglycemic drugs used in functional foods or pharmaceuticals.

Adsorption of Pb2+ from Aqueous Solutions Using Novel Functionalized Corncobs via Atom Transfer Radical Polymerization.

The present study developed novel functionalized corncobs introducing brushes with dense and active carboxyl groups (-COOH), named MC-g-PAA, for the highly efficient adsorption of Pb2+ from aqueous solutions. MC-g-PAA were synthesized via atom transfer radical polymerization (ATRP) and characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The amount of Pb2+ adsorbed on MC-g-PAA by hydrolysis with t-BuOK was 2.28 times greater than that with NaOH, attributed to the larger steric effect of t-BuOK, which reduced the hydrolysis of the bromo-ester groups. The influence of different parameters including the solid/liquid ratio, working solution pH, sorption temperature, and initial concentration and sorption time on the adsorption of Pb2+ were investigated in detail in batch experiments. Thermodynamic studies have shown that the adsorption process was spontaneous, endothermic, and accompanied by an increase in randomness. A better fit for the isotherm data was obtained using the Langmuir model than for the other four models and the maximum amount ( q max ) of Pb2+ adsorbed on MC-g-PAA was 342.47 mg/g, which is 21.11 times greater when compared with that of pristine corncobs (16.22 mg/g). The adsorption of Pb2+ on MC-g-PAA was very fast and followed the pseudo-second-order kinetic equation with a correlation coefficient of 0.99999. This monolayer adsorption process was dominated by chemical adsorption, and may proceed according to complexation and electrostatic interactions between Pb2+ and the carboxylate groups. This study indicated that MC-g-PAA could be successfully used as an adsorbent for the removal of Pb2+ from aqueous solutions due to its excellent efficiency.

milR4 and milR16 Mediated Fruiting Body Development in the Medicinal Fungus Cordyceps militaris.

Cordyceps militaris readily performs sexual reproduction, thus providing a remarkably rich model for understanding the processes involved in sexual development. It could regulate expression of human genes by diet-derived miRNA-like RNAs (milRNAs). However, the study of miRNAs in C. militaris has been limited. In the present study, genes encoding Dicers, Argonautes, and RNA-dependent RNA polymerases were identified. Illumina deep sequencing was performed to characterize the milRNAs in C. militaris at asexual and sexual development stages. Total 38 milRNAs were identified and five milRNAs were validated by northern blot and qRT-PCR, out of which, 19 were specific for sexual development. Importantly, the fungi could not form fruiting bodies after disruption of milR4, while the perithecium was formed in advance after over-expression of milR4. Abnormal pale yellow fruiting body primordium, covered with abnormal primordium, was formed in the strain with miR16 disruption. Although no milR4 or milR16 target genes were identified, differential expression of many different genes involved in mycelium growth and sexual development (mating process, mating signaling, and fruiting body development) among these mutants were found. Overall, milRNAs play vital roles in sexual development in C. militaris.

Genes involved in Beauveria bassiana infection to Galleria mellonella.

The ascomycete fungus Beauveria bassiana is a natural pathogen of hundreds of insect species and is commercially produced as an environmentally friendly mycoinsecticide. Many genes involved in fungal insecticide infection have been identified but few have been further explored. In this study, we constructed three transcriptomes of B. bassiana at 24, 48 and 72 h post infection of insect pests (BbI) or control (BbC). There were 3148, 3613 and 4922 genes differentially expressed at 24, 48 and 72 h post BbI/BbC infection, respectively. A large number of genes and pathways involved in infection were identified. To further analyze those genes, expression patterns across different infection stages (0, 12, 24, 36, 48, 60, 72 and 84 h) were studied using quantitative RT-PCR. This analysis showed that the infection-related genes could be divided into four patterns: highly expressed throughout the whole infection process (thioredoxin 1); highly expressed during early stages of infection but lowly expressed after the insect death (adhesin protein Mad1); lowly expressed during early infection but highly expressed after insect death (cation transporter, OpS13); or lowly expressed across the entire infection process (catalase protein). The data provide novel insights into the insect-pathogen interaction and help to uncover the molecular mechanisms involved in fungal infection of insect pests.

Ameliorative effect of Trametes orientalis polysaccharide against immunosuppression and oxidative stress in cyclophosphamide-treated mice.

The present study evaluated the ameliorative effects of Trametes orientalis polysaccharide (TOP-2) against cyclophosphamide (CP) induced toxicity in mice. Intraperitoneal administration of TOP-2 not only effectively increased the thymus, spleen, heart, liver, and kidney indices, but also significantly enhanced the phagocytic activities of macrophages and splenocyte proliferation, dose-dependently. The lowered nitric oxide level of macrophages after CP treatment was elevated by TOP-2 administration. Impaired splenic natural killer cells and cytotoxic T lymphocytes activities were remarkably enhanced by TOP-2. Furthermore, the levels of interleukin-2, interferon-γ, Immunoglobulin A, immunoglobulin G, and immunoglobulin M were notably reduced by CP, while TOP-2 abolished these effects. TOP-2 could also effectively increase the total antioxidant capacity, superoxidase dismutase, catalase and glutathione peroxidase activities, and inhibit the increase in malondialdehyde level. These results indicate that TOP-2 may be of therapeutic value in ameliorating the immunosuppression and oxidative stress caused by CP treatment, through its immunomodulatory and antioxidant potential.