Accelerated photocatalytic degradation of organic pollutants using graphitic carbon nitride assisted chemistry of MXenes 2D/2D nanocomposites

Vigneshwaran Sivakumar(Sivakumar Vigneshwaran),Do-Gun Kim(김도군),Seo-Oh Ko(고석오) 대한환경공학회 2022 대한환경공학회 학술발표논문집 Vol.2022 No.11

Antitumor and antioxidant activities of Bryonia laciniosa against Ehrlich's Ascites Carcinoma bearing Swiss albino mice

Sivakumar, T,Kumar, R Sambath,Perumal, P,Vamsi, MLM,Sivakumar, P,Kanagasabai, R,Baskaran, MV,Karki, Subhas S,Mazumder, UK,Gupta, M Kyung Hee Oriental Medicine Research Center 2005 Oriental pharmacy and experimental medicine Vol.5 No.4

The plant Bryonia laciniosa (Family: Cucurbitaceae) has been indicated for the treatment of various diseases one among which is cancer. The purpose of this study was investigating experimentally the possible anti-tumor effect and antioxidant role of Bryonia laciniosa leaves in animal model. The methanol extract of Bryonia laciniosa (MEBL) administered at the doses of 62.5, 125 and 250 mg/kg in mice for 14 days after 24 h of tumor inoculation. The effect of MEBL on the growth of transplantable murine tumor, life span of EAC bearing mice, hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. Treatment with MEBL decreased the tumor volume and viable cell count thereby increasing the life span of EAC bearing mice and brought back the hematological parameter more or less normal level. The effect of MEBL also decreases the levels of lipid peroxidation and increased the levels of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The present work indicates that the methanol extract of Bryonia laciniosa exhibited significant antitumor and antioxidant activity in vivo.

Recent Advances in the Cultivation and to Enhance the Active Components of Ganoderma lucidum

Sivakumar Manickam,Surya Sudheer,Zain Taha 한국버섯학회 2017 버섯 Vol.21 No.2

Ganoderma lucidum is one of the most popular medicinal mushrooms of Asian region having promising immune enhancing properties. This single species of mushroom has over 400 bioactive compounds and possess properties relating to battling tumours, viruses, bacteria, inflammation, platelet-aggregation, immune system modulation among many others. There are documented reports of G. lucidum fighting the activity against HIV/AIDS and diabetes. Owing to such a wide range of medicinal applications, the global consumption of G. lucidum is high, which has resulted in a plethora of commercially available patented products. These products have G. lucidum as an active constituent and are usually marketed as food supplements but are also available in the form of creams, hair tonics and medicinal soaps. The growing demand and the high cost of G. lucidum in the local market have enforced to think about a range of novel methods for the cultivation of this mushroom. We explored different novel strategies in this direction. In the first approach, the widely available agricultural residues of oil palm biomass (empty fruit bunch fibres, EFB) from Malaysia were used to cultivate this mushroom with cheap cost. The required conditions for the growth of this mushroom were studied by employing a pilot-scale cultivation in a mushroom farm. From the results it was scrutinized that oil palm waste fibres are the potential source of cultivating G. lucidum either alone or in combination of substrates. In the second strategy, the effect of UV-C radiation on the physical growth of G. lucidum mycelium has shown positive results. Results of 10 and 15 min of UV-C exposure treatments per 24 h showed a 30% increase in the diameter of mycelium over control in Potato Dextrose Agar medium petri-plates. Using EFB as substrates not only supports the G. lucidum cultivation but also offers a viable alternative for the management of solid waste in oil palm plantations of Malaysia. These results stipulate a better and stronger mushroom in terms of its bioactive compounds content and better growth parameters. Moreover, it also benefits the local mushroom farmers in Malaysia for the easy availability of the substrate materials and with better economy. The techniques involved can be propagated to the local Ganoderma industry for improvised cultivation for better output. A high output would also mean profitable business resulting in revolutionizing the economics of Ganoderma markets all over the world.

Hybrid Model-based Framework for Soft Sensing and Forecasting Key Process Variables in the Production of Hyaluronic Acid by Streptococcus zooepidemicus

Sivakumar Rathinavelu,Satya Sai Pavan,Senthilkumar Sivaprakasam 한국생물공학회 2023 Biotechnology and Bioprocess Engineering Vol.28 No.1

Hyaluronic acid (HA), a glycosaminoglycan polymer, is widely used in the biomedical and cosmetic industries. Due to highly viscous nature of the HA fermentation broth, it is difficult to capture the dynamics of its bioprocess with physical sensors in real-time. The goal of this study was to track non-invasively the state variables involved in HA production process and deducing the critical process parameters based on the recorded process inputs. The framework employed in this study is based on a hybrid model that predicts HA and biomass concentration using online bioreactor data (pH, DO%, %CO2 evolved, feed rate, and agitation rate) to ensure real-time tracking of HA bioprocess dynamics. A HA fermentation dataset with data from historical batches and freshly performed fedbatch runs for various specific growth rate set-points (μsp) was created. The dataset was used to train the hybrid model, which was then used to predict biomass and HA concentration for test runs, with a mean squared error of prediction ranging from 0.018 to 0.049 (g/L)2. Furthermore, recurrent neural networks were evaluated in forecasting the specific growth rate (μ) and HA productivity rate (qHA) to observe the desired process trajectory. The current study addressed the scope of application of hybrid model based soft-sensor to predict the trend of process parameters of HA fermentation.

Influence of combined radial location and growth on the leakage performance of a rotating labyrinth gas turbine seal

Sivakumar Subramanian,A. S. Sekhar,B. V. S. S. S. Prasad 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.6

Leakage characteristics, influenced by centrifugal and thermal radial growth are determined computationally for a generic rotating labyrinthseal used in the gas turbine secondary air system. Three seal locations, namely, R25, R50 and R75 are represented by means ofvarying the rotor radius mimicking different radial positions of the seal from the shaft axis. The combined influence of seal location andits radial (Centrifugal and thermal) growth on the leakage performance is investigated for a wide-ranging speeds from 1000 to 3000 rad/s,temperatures ranging from 200 to 450 oC and pressure ratios varying from 1.1 to 2.5, for a chosen initial clearance of 500 micron. Acomparison of the effect of rotation and temperature gradient among different rotors shows that the radial growth and leakage flow ratessignificantly vary with the increasing radius.

Drying and energy aspects of tapioca sago processing-An experimental field study

Sivakumar R.,Elayaperumal A.,Saravanan R. 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.6

The drying characteristics of tapioca sago were studied using four different drying methods--Open sun drying (OSD), Conveyor beltdrying (CBD), Bin drying (BD) and Fluidized bed drying (FBD)--in an industry located in Tamilnadu, India (Latitude: 11.494347° N;Longitude: 78.272264° E). The BD and FBD dryers were designed and fabricated as pilot scale models in the laboratory with respectivecapacity of 5 kg/h and 10 kg/h; CBD (1000 kg/h) and OSD are the commercial drying operations currently employed in industrial processing. The drying time, energy and exergy aspects of all the drying methods were compared along with the achieved final moisture content,color and quality of the dried products. The highest Energy utilization ratio (EUR) was found in CBD and FBD in the range of 20-76 % and 10-67 %, respectively. The exergy efficiency was initially low in all the cases but increased to 80 % towards the end of thedrying process.

Evolution of Agrometeorology at the Global Level

Sivakumar, M.V.K. 한국농림기상학회 2004 한국농림기상학회지 Vol.6 No.2

농업기상은 지난 100년동안 서술적인 학문에서 물리학적 및 생물학적 법칙을 활용하는 정량적인 학문적으로 발전되어 왔다. 농업인들은 기후와 기상정보의 이용으로 수익을 개선할 수 있다는 점을 더욱 깊이 인식하게 되었고, 이는 농업기상서비스에 대한 수요를 증대로 이어질 것이라는 점은 의심할 여지가 없다. 그러므로 21세기 농업기상의 필요성과 전망을 크게 두 가지 주제로 구분하는 것은 시의 적절하다 할 수 있다. 즉 농업생산을 위한 농업기상서비스와 이들 서비스를 지원하기 위한 농업기상자원시스템의 중요한 구성요소인 자료, 연구, 정책 및 훈련/교육/지도의 중요성이 더욱 강조될 것이다. 몬티쓰박사가 말한 바와 같이, 식량공급은 궁극적으로 기상자원의 잠재성을 탐구하거나 악기상의 영향을 최소화하는 농민의 기술력에 좌우될 것이다. 장비, 자료관리체계, 기후예측, 작물모의, 농업기상정보 배분등에 있어서의 최근 발전으로 인해 농민이 이러한 핵심기술을 습득, 향상시키는 것을 돕기 위해 필요한 도구들이 농업기상학자들에게 제공되고 있다. 따라서 향후 농업기상기술의 현장활용은 그 전도가 매우 밝다 하겠으며, 이러한 기술의 현장활용을 통해 지속농업의 촉진 및 빈곤타파 등에 농업기상이 근원적인 커다란 기여를 할 수 있을 것이다. Agricultural meteorology has advanced during the last 100 years from a descriptive to a quantitative science using physical and biological principles. The agricultural community is becoming more aware that using climate and weather information will improve their profitability and this will no doubt increase the demand for agrometeorological services. Hence it is timely that the needs and perspectives for agrometeorology in the 21^(st) Century are grouped under two major headings: agrometeorological services for agricultural production and agrometeorological support systems for such services. Emphasis must be placed on the components of such support systems comprising of data, research, policies and training/ education/extension. As Monteith (2000) mentioned, food supplies ultimately depend upon the skill with which farmers can exploit the potential of good weather and minimize the impact of bad weather: Recent developments in instrumentation, data management systems, climate prediction, crop modelling, dissemination of agrometeorological information etc., provide agrometeorologicts the tools necessary help the farmers improve such skills. The future for operational applications of agricultural meteorology appears bright and such applications could contribute substantially to promote sustainable agriculture and alleviate poverty.

Biodiversity of Microalgae and Their Elemental Components from Veeranam Lake, Tamilnadu, India

Sivakumar K.,R. Senthilkumar 한국하천호수학회 2008 생태와 환경 Vol.41 No.2

Photocatalytic and Antimicrobial Activities of Poly(aniline-co-o-anisidine)/Zinc Oxide Nanocomposite

Sivakumar, K.,Kumar, V. Senthil,Shim, Jae-Jin,Haldorai, Yuvaraj Chemic Publishing Company 2014 Asian Journal of Chemistry Vol.26 No.2

<P>The conjugated poly(aniline-co-o-anisidine)/zinc oxide,[poly(Ani-co-oAs)/ZnO] nanocomposite was prepared by in-situ chemical oxidative polymerization of comonomers with ZnO nanoparticles and :applied as a photocatalyst for the degradation of methylene blue dye. Scanning electron microscopy, transmission electron microscopy:X-ray diffraction, Fourier transform infrared spectroscopy and UV-visible spectroscopy measurements were used to characterize the resulting pure copolymer and nanocomposite. Transmission electron microscopy analysis showed that the nano-particles with amean diameter of 15-25 nm were dispersed in the copolymer matrix. Thermogravimetric analysis indicated that the nanocomposite had a higher decomposition temperature than the pure copolymer. The conductivity measurements showed the resulting nanocomposite possessed higher conductivity as compared to the pure copolymer. The photocatalytic activity results indicated the degradation of methylene blue dye by 97%, over the surface of nanocomposite catalyst under UV-irradiation for 3 h. The nanocomposite exhibited good antimicrobial activity against the microbial species and the dear zone diameter Of the microbial inhibition is correlated to the antimicrobial activity of nanocomposite</P>

Antioxidants Supplementation on Acid Base Balance during Heat Stress in Goats

Sivakumar, A.V.N.,Singh, G.,Varshney, V.P. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.11

The effects of vitamin C and vitamin E with selenium on acid-base balance and some stress hormones were evaluated during heat stress in goats. Goats, 1.5 years of age, were divided into control, heat stress and antioxidant treatment groups 1, 2 and 3. Except for the control, all groups were exposed to a temperature of $40{\pm}2^{\circ}C$ with a relative humidity of 30% for 5 h/d for 21 days in a psychrometric chamber. Rectal temperature and respiratory rates were recorded daily post exposure. Blood samples were collected on every 3rd day for estimation of plasma vitamins C and E, total antioxidant activity and hormones, and separate blood samples were taken to estimate acid-base status. The rectal temperature and respiratory rates were increased (p<0.05) in the heat stress group only. Except for pH and $pO_2$, which were increased significantly (p<0.05) other parameters of acid-base balance such as $pCO_2$, $HCO_3^-$, $TCO_2$, BEb, BEcef, PCV and Hb were significantly decreased (p<0.05) in the heat stress group. An improvement in acid-base status was noted in the antioxidant supplemented groups. Prolactin and cortisol levels were significantly (p<0.05) higher and free T3 and T4 levels were significantly (p<0.05) lower in the heat stress group. Levels of prolactin and cortisol were decreased and free T3 and T4 were increased in antioxidant treatment groups. Different levels of antioxidant supplementation resulted in similar protection against heat stress.