Identification of keratinolytic function in Chryseobacterium camelliae Dolsongi-HT1 isolated from Green Tea

Keratin forms a major component of the epidermis, hair, feathers, nails, scales and etc. However, old keratins on the skin are not preferred for the beauty purpose. Therefore, in the highly efficient and low irritative method to remove old keratin on the skin is highly desired. For this purpose, one of the appropriate methods is the enzymatic lysis of keratin. To screen a novel keratinase, a novel microorganism having keratinolytic activity was isolated by enrichment culture. Newly screened microorganism was isolated from green tea in dolsong-i tea garden, Jeju and identified as Chryseobacterium camelliae Dolsongi-HT1. The keratinase activity of C. camelliae Dolsongi-HT1 was confirmed in the culture media. The effect of pH and temperature were studied using cell culture media. Crude keratinase showed high activity over a wide range of temperature (37 to 60°C) and showed the highest activity at 50°C. Optimum pH of keratinase activity of crude keratinase was pH 8. Interestingly, this enzyme activity was maintained over 50% at pH 6. This feature is promising for the application to cosmetics. The effect of nitrogen source for cell culture was also investigated. Among the various nitrogen sources, the highest keratinase activity (relative activity of 366.4%) was detected when cells were cultured using tryptone extract. To study the keratinolytic activity effect of keratin on the skin, the keratin of skin was obtained using tape stripping. It was found that the structure of keratin was degraded by crude keratinase. To identify the keratinase, the complete genome of C. camelliae Dolsongi-HT1 was sequenced. Because keratinases are regarded as serine or metalloprotease group, we searched for those proteases in the C. camelliae Dolsongi-HT1 genome sequence. As s result, over twenty putative keratinases could be identified. Further research to identify desired keratinases should be performed

Sequential whole cell conversion process for production of D-psicose and D- mannitol from D-fructose

Rare sugars, which exist only limited quantities naturally, have received considerable attention because of its various specific nutritional and biological functions. Likewise, D-psicose (D-ribo-2-hexulose or D-allulose), a C-3 epimer of D-fructose, has many uses which include reducing intra-abdominal fat accumulation, protecting pancreas beta-islets and improving insulin sensitivity. Especially, D-psicose has only 0.3% calories compared to sucrose, while it has 70% relative sweetness. Additionally, in 2012, D-psicose was approved as a food additive and designated as Generally Recognized As Safe (GRAS) by Food and Drug Administration (FDA). Despite such abundant advantages, there is no economical way of mass production of D-psicose. Recently, biological production of D-psicose from D-fructose using D-psicose 3-epimerase (DPE) has been developed. However, the conversion yield is below 30%, which causes an undesirable increase of purification cost because of the similar solubility of D-psicose and D-fructose. Thus, we addressed the problem by converting the residual fructose, after the reaction of D-psicose production, to D-mannitol, which has a low solubility. The sequential whole cell conversion reactions for D-psicose and D-mannitol allow a convenient and economic purification of both products. This work was supported by a grant from the Next-Generation BioGreen 21 Program (SSAC, grant#: PJ01106201), RDA, Korea. Reference 1) Carsten Bäumchen & Stephanie Bringer-Meyer (2007), Expression of glf Z.m. increases D-mannitol formation in whole cell biotransformation with resting cells of Corynebacterium glutamicum, Appl Microbiol Biotechnol 76(3):545–52. 2) Ortiz, M. E., Bleckwedel, J., Raya, R. R., & Mozzi, F. (2013). Biotechnological and in situ food production of polyols by lactic acid bacteria, Appl Microbiol Biotechnol 97:4713-4726 3) Park, Y., Oh, E. J., Jo, J., Jin, Y., & Seo, J. (2016). Recent advances in biological production of sugar alcohols. Curr Opin Biotechnol 37:105–113

Robust Distributed Clustering Algorithm Over Multitask Networks

We propose a new adaptive clustering algorithm that is robust to various multitask environments. Positional relationships among optimal vectors and a reference signal are determined by using the mean-square deviation relation derived from a one-step least-mean-square update. Clustering is performed by combining determinations on the positional relationships at several iterations. From this geometrical basis, unlike the conventional clustering algorithms using simple thresholding method, the proposed algorithm can perform clustering accurately in various multitask environments. Simulation results show that the proposed algorithm has more accurate estimation accuracy than the conventional algorithms and is insensitive to parameter selection.11Ysciescopu

Data-Reserved Periodic Diffusion LMS With Low Communication Cost Over Networks

In this paper, we analyze diffusion strategies in which all nodes attempt to estimate a common vector parameter for achieving distributed estimation in adaptive networks. Under diffusion strategies, each node essentially needs to share processed data with predefined neighbors. Although the use of internode communication has contributed significantly to improving convergence performance based on diffusion, such communications consume a huge quantity of power in data transmission. In developing low-power consumption diffusion strategies, it is very important to reduce the communication cost without significant degradation of convergence performance. For that purpose, we propose a data-reserved periodic diffusion least-mean-squares (LMS) algorithm in which each node updates and transmits an estimate periodically while reserving its measurement data even during non-update time. By applying these reserved data in an adaptation step at update time, the proposed algorithm mitigates the decline in convergence speed incurred by most conventional periodic schemes. For a period p, the total cost of communication is reduced to a factor of 1/p relative to the conventional adapt-then-combine (ATC) diffusion LMS algorithm. The loss of combination steps in this process leads naturally to a slight increase in the steady-state error as the period p increases, as is theoretically confirmed through mathematical analysis. We also prove an interesting property of the proposed algorithm, namely, that it suffers less degradation of the steady-state error than the conventional diffusion in a noisy communication environment. Experimental results show that the proposed algorithm outperforms related conventional algorithms and, in particular, outperforms ATC diffusion LMS over a network with noisy links.11Ysciescopu

Arctic-North Pacific Coupled Impacts on the Late Autumn Cold in North America

The Pacific Decadal Oscillation (PDO) is known to bring an anomalously cold (warm) period to southeastern (northwestern) North America during the cold season of its positive phase through a Rossby wave linkage. This study provides evidence that the remote connection between the North Pacific and the downstream temperature over central North America is strengthened by the warm arctic conditions over the Chukchi and East Siberian Sea, especially in the late autumn season. The modulation effect of the Arctic manifests itself as an altered Rossby wave response to a transient vorticity forcing that results from an equatorward storm track shift, which is induced collaboratively by the PDO and the warm Arctic. This observational finding is supported by two independent modeling experiments: 1) an idealized coupled GCM experiment being nudged toward the warm arctic surface condition and 2) a simple stationary wave model (SWM) experiment forced by transient eddy forcing

Direct shoot organogenesis from petiole and leaf discs of Withania somnifera (L.) Dunal

An efficient and reproducible procedure is described for direct shoot regeneration using petiole and leaf explants of Withania somnifera (L.). The shoots were mainly induced from the distal end of the petiole, whereas in leaf explants, shoot regeneration was initiated from the basal part and wounded tissue. The regeneration medium that induced the highest numbers of shoots in the petiole and leaf explants was Murashige and Skoog (MS) medium supplemented with 2 mg/l N6-benzyladenine (BA) alone or with 0.1 mg/l a-naphthalene acetic acid (NAA). The frequency of shoot regeneration was greatly influenced by the type of explant, the carbon source, the orientation of the explant, and the basal medium used in the regeneration medium. Explants produced shoot buds and adventitious shoots within four weeks. Histological analysis of the regenerating shoots showed that the shoot buds emerged from sub epidermal parenchymal cells, with no intermediate callus formation. Plantlets were rooted on MS alone or MS containing different concentrations of 3-indolebutyric acid (IBA). The addition of 1 mg/l IBA to the medium was most effective in inducing root formation. The regenerated plantlets were acclimatized in the greenhouse and successfully transferred to the field, with a 90% survival rate. The acclimatized plants showed normal flowering and were not morphologically different from the seed-derived mother plants.Key words: Histology, medicinal plant, plant growth regulator, plant regeneration, Withania somnifera

S3: School Zone Safety System Based on Wireless Sensor Network

School zones are areas near schools that have lower speed limits and where illegally parked vehicles pose a threat to school children by obstructing them from the view of drivers. However, these laws are regularly flouted. Thus, we propose a novel wireless sensor network application called School zone Safety System (S3) to help regulate the speed limit and to prevent illegal parking in school zones. S3 detects illegally parked vehicles, and warns the driver and records the license plate number. To reduce the traveling speed of vehicles in a school zone, S3 measures the speed of vehicles and displays the speed to the driver via an LED display, and also captures the image of the speeding vehicle with a speed camera. We developed a state machine based vehicle detection algorithm for S3. From extensive experiments in our testbeds and data from a real school zone, it is shown that the system can detect all kinds of vehicles, and has an accuracy of over 95% for speed measurement. We modeled the battery life time of a sensor node and validated the model with a downscaled measurement; we estimate the battery life time to be over 2 years. We have deployed S3 in 15 school zones in 2007, and we have demonstrated the robustness of S3 by operating them for over 1 year