Production of lepidimoide by an endophytic fungus from polysaccharide extracted from Abelmoschus sp.: identification of the product and the organism producing it

A highly potent allelopathic factor, lepidimoide, was initially extracted from mucilage of germinated cress seeds. Polysaccharide extracted from okra (Abelmoschus esculentum Moench) is considered to have a similar structure to lepidimoide as its repeating unit. We therefore initiated the screening of enzymes capable of degrading okra polysaccharide into lepidimoide from endophytes. We discovered an endophytic fungal strain AHU9748 isolated from Coleus galeatus, which produced an oligosaccharide having similar properties to lepidimoide on thin layer chromatography. The physico-chemical data from ESI-MS, NMR spectra and other analyses also showed the purified product to be identical to lepidimoide. The strain AHU9748 was identified as a fungus belonging to the coelomycetes, closely related to the genus Colletotrichum, based on morphological characteristics and sequence analysis of the 18S rDNA and ITS region.     

The inhibitory effects of heavy metals and organic compounds on the net maximum specific growth rate of the autotrophic biomass in activated sludge

A respirometry technique can be applied as an effective method to determine the net maximum specific growth rate of autotrophic biomass under both normal conditions and when inhibition occurs. The net maximum specific growth rate of uninhibited autotrophic biomass, expressed as (mu(A)-b(A)), is approximately 0.8 per day [Proceeding of the International Congress on CHISA, Prague, 2002, p. 1]. Several heavy metals and organic compounds have inhibitory effects. Copper (Cu(2+)) has stronger inhibitory effects than zinc (Zn(2+)), and inhibits the nitrification process by 50% at 0.08 mg/l [(mu(A)-b(A)) = 0.4 per day], while the same concentration of Zn(2+) establishes 12% inhibition only [(mu(A)-b(A)) = 0.75 per day]. Inhibition with Cu(2+) starts at concentrations above 0.05 mg/l, while this is above 0.3mg/l for Zn(2+). The inhibition of the nitrification process is complete at 1.2mg/l for both Cu(2+) and Zn(2+). Among the selected organic compounds tested n the experiments, the degree of inhibition decreases as follow: chlorobenzene>trichloroethylene (TCE)>phenol>ethylbenzene. Chlorobenzene already inhibits the autotrophic biomass at 0.25 mg/l. The nitrification process is totally inhibited by adding 0.75 mg/l of chlorobenzene. TCE has a less inhibitory effect on the nitrification process and 50% inhibition is noticed at 0.75 mg/l TCE. The nitrification process is totally inhibited at 1mg/l TCE. Phenol inhibits the nitrification for 50% at 3 mg/l. The inhibitory effect of phenol is almost constant in the range 4-10 mg/l and complete inhibition is reached at 50 mg/l. The inhibitory effect of ethylbenzene is 50% at 8 mg/l and the autotrophic biomass is totally inhibited at 50 mg/l. Experimental findings are compared with literature data, which generally and significantly overestimate the inhibition threshold concentrations.     

光交换技术的发展趋势

本文根据国内外近十年来发表的光交换器件及光交换系统方面的文献对光交换技术的发展趋势加以综述。本文把光交换器件分为两大类,即光相关器件与光逻辑器件,并举例加以说明。对光交换系统则分为空分交换,时分交换及波分交换三大类予以叙述。并指出三维交换矩阵的开发可能是光交换技术独立于电子交换技术的一种新模式,利用光传输在时空上的特点,估计在近几年内光交换技术还会有新的突破。     

β-Ca_3(PO_4)_2人陶瓷的生物降解过程研究

本文论述了β-Ca_3(PO_4)_2多孔陶瓷的制备方法及其动物试验结果。通过扫描电镜观察、X射线拍片、电子能谱分析等方法,研究了材料在动物体内的降解过程,并从材料内部结构角度探讨了其生物降解机理。     

A Cell-Based Systematic Review on the Role of Annexin A1 in Triple-Negative Breast Cancers

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype that is often associated with a poorer prognosis and does not respond to hormonal therapy. Increasing evidence highlights the exploitability of Annexin A1 (AnxA1), a calcium dependent protein, as a precision medicine for TNBC. To systematically summarize the role of AnxA1 and its associated mechanisms in TNBC, we performed data mining using three main databases: PubMed, Scopus, and Ovid/Medline. The papers retrieved were based on two different sets of key words such as “Annexin A1” or “Lipocortin 1” and “Breast cancer” or “TNBC”. A total of 388 articles were identified, with 210 chosen for comprehensive screening and 13 papers that met inclusion criteria were included. Current evidence from cell culture studies showed that AnxA1 expression is correlated with NF-κB, which promotes migration by activating ERK phosphorylation. AnxaA1 also activates TGF-β signaling which upregulates MMP-9 and miR196a expression to enhance epithelial-mesenchymal transition and migratory capacity of TNBC cells. AnxA1 can steer the macrophage polarization toward the M2 phenotype to create a pro-tumor immune environment. Existing research suggests a potential role of AnxA1 in the metastasis and immune landscape of TNBC tumors. Preclinical and clinical experiments are warranted to investigate the feasibility and effectiveness of targeting AnxA1 in TNBC.     

Physicochemical Properties and Starch Digestibility of Autoclaved-Cooled Water Yam (Dioscorea alata L.) Flour

Water yam (Dioscorea alata L.) is suitable for resistant starch high flour because of its high amylose content. The purple, yellow, and white water yams were treated by autoclaving and cooling with one, two, and three cycles to obtain resistant starch. Water yam tubers were cooked in an autoclave for 15 min, and then cooled prior to drying. Autoclaving–cooling of water yams decreased protein, fat, dietary fiber, water soluble polysaccharide, dioscorin, and diosgenin but increased amylose and sugar. The treatments significantly raised resistant starch and reduced in vitro starch digestibility that depended on water yam types, and affected starch granule morphology.     

Quantitative Analysis of Lard in Cosmetic Lotion Formulation Using FTIR Spectroscopy and Partial Least Square Calibration

Fourier transform infrared (FTIR) spectroscopy in combination with chemometrics of partial least squares (PLS) has been optimized for rapid determination of lard in a binary mixture with palm oil in a cosmetic lotion formulation. Lard, palm oil, and a binary mixture were extracted from matrix samples using liquid–liquid extraction, evaporated with a vacuum rotary evaporator, and the fat/oil yielded was further subjected to FTIR spectrometric measurement using attenuated total reflectance (ATR) as a sampling handling technique. The level of lard in the mixture with palm oil in the lotion formulation was quantified at frequency region of 1,200–1,000 cm^?1. The PLS calibration model reveals good correlation between the actual value of lard (x-axis) and the FTIR predicted value (y-axis) with a coefficient of determination (R²) of >0.99. Furthermore, the classification between lotions with and without lard in their formulation was performed using principal component analysis using the same frequency region used for quantification. The developed method was subsequently used for analysis of cosmetic lotions commercially available in the market. All samples analyzed did not contain lard in their formulations.     

Ochratoxigenic Black Aspergilli Isolated from Dried Agricultural Products in Yogyakarta, Indonesia

Black aspergilli, the potential ochratoxin A （OTA） producers, were predominant fungi in fermented cocoa bean, coffee bean and dried cassava in Yogyakarta. Identification of black aspergilli at species level will be useful to make clear link between OTA contamination on food product and the toxin producer. The objective of this study was to identify the species of the black aspergilli producing OTA which contaminated dried agriculture products. In this study, 16 isolates were obtained, and four isolates among of them （YAC-9, YAK-6, YAK-12 and YAG-2） were found as OTA producing-strains, with the highest OTA found on Yeast Extract Sucrose （YES） solid medium of 57.68 ppb. Based on morphological characters, 16 isolates can be grouped into four species, after confirmation by molecular data based on PCR method, the groups were identified as A. carbonarius, A. niger, A. tubingensis and A. aculeatus. OTA producing-strains were identified as A. carbonarius and A. niger, meanwhile, A. tubingensis and A. aculeatus were found as non-OTA producing-strains.     

Improved Transformation and Regeneration of Indica Rice: Disruption of SUB1A as a Test Case via CRISPR-Cas9

Gene editing by use of clustered regularly interspaced short palindromic repeats (CRISPR) has become a powerful tool for crop improvement. However, a common bottleneck in the application of this approach to grain crops, including rice (Oryza sativa), is efficient vector delivery and calli regeneration, which can be hampered by genotype-dependent requirements for plant regeneration. Here, methods for Agrobacterium-mediated and biolistic transformation and regeneration of indica rice were optimized using CRISPR-Cas9 gene-editing of the submergence tolerance regulator SUBMERGENCE 1A-1 gene of the cultivar Ciherang-Sub1. Callus induction and plantlet regeneration methods were optimized for embryogenic calli derived from immature embryos and mature seed-derived calli. Optimized regeneration (95%) and maximal editing efficiency (100%) were obtained from the immature embryo-derived calli. Phenotyping of T₁ seeds derived from the edited T₀ plants under submergence stress demonstrated inferior phenotype compared to their controls, which phenotypically validates the disruption of SUB1A-1 function. The methods pave the way for rapid CRISPR-Cas9 gene editing of recalcitrant indica rice cultivars.