1 PhD, Department of Genetics, School of Biological Sciences, Madurai Kamaraj University
2 MSc Biotechnology, Department of Biotechnology, University of Madras, Guindy Campus, Chennai, Tamilnadu
3 BSc Chemistry, Meenakshi College for Women, University of Madras, Chennai, Tamilnadu
Sustainable Mesoporous Silica Nanoparticles from Groundnut Shells for High-Efficiency Cr(VI) Removal: Kinetics, Isotherms, and Mechanism Insights Shalini Kannan, K. Geetha, S. Mariaamalraj, K. Thavasilingam Chemical and Biochemical Engineering Quarterly, 2026 The increasing concentrations of toxic hexavalent chromium [Cr(VI)] in aquatic <br /> systems pose a major threat to human health and the environment, necessitating the development of high-performance, reasonably priced, and environmentally friendly adsorbents. Mesoporous silica nanoparticles (SiNPs) were synthesized from groundnut shell waste via alkaline extraction followed by acid precipitation, yielding 21 %. Amorphous, mesoporous silica with a high surface area (84.61 m² g–1) and a large number of silanol groups was confirmed by characterization (XRD, FTIR, SEM–EDS, and BET). Batch adsorption experiments revealed that the maximum Cr(VI) removal efficiency reached 92 % at pH 4, with an optimum equilibrium adsorption capacity (qₑ) of 4.5955 mg g–1. The process followed pseudo-second-order kinetics (R2 = 0.99) and the Freundlich isotherm model (R2 = 0.9826), indicating chemisorption. Surface complexation was confirmed by post-adsorption analyses, demonstrating the effectiveness the SiNPs as environmentally friendly adsorbents for wastewater treatment.
Evaluation of anti rheumatic activity of Piper betle L. (Betelvine) extract using in silico, in vitro and in vivo approaches Selvakumar Murugesan, Devibala Ravichandran, Dinesh Kumar Lakshmanan, Guna Ravichandran, Velusamy Arumugam, Karthik Raju, Karuppasamy Geetha, Sivasudha Thilagar Bioorganic Chemistry, 2020 Rheumatoid Arthritis is a chronic, inflammatory, and systemic autoimmune disease, it affects elders worldwide. Herbal medicines have been used for the treatment of various ailments from ancient times. Betelvine (Piper betle L.) leaves have long been used in Asian countries as a medicine to relieve pain and some metabolic diseases. The present study of methanolic extract of phytochemical analysis confirms the presence of alkaloids, tannins, terpenoids, saponins, steroids, total flavonoids and total phenols. GC-MS analysis of MeOH extract of Piper betle (PBME) revealed the presence of 40 bioactive compounds. In vitro antioxidant and anti-inflammatory assays showed greater inhibitory effect. The anti-arthritic effects of PBME at 250 and 500 mg/kg concentration showed recovery from joint damage in in vivo rat model. Among the 40 GC-MS derived bioactives, 4-Allyl-1,2-Diacetoxybenzene exhibited the higher interactions with minimized binding energy to the RA targets of MMP 1 (-6.4 kcal/mol), TGF-β (-6.9 kcal/mol), IL-1β (-5.9 kcal/mol). Further, the effect of PBME extract against RA molecular disease targets (IL-1β, MMP1 and TGF- β) were studied using Real-time PCR. These results substantiate that P. betle leaves could be a source of therapeutics for the treatment of rheumatoid arthritis.
Purification of endoxylanase from bacillus pumilus B20 for production of prebiotic xylooligosaccharide syrup; An in vitro study Karuppasamy Geetha, Paramasamy Gunasekaran Iranian Journal of Biotechnology, 2017 Background: The need for more cost-effective compounds is imperative because the demand for prebiotic compounds is ever on the rise. Objective: The focus of this study is the purification of the endoxylanase from Bacillus pumilus B20 and its application in a cost-effective production of the prebiotic xylooligosaccharide (XOS) syrup having a high concentration of oligosaccharides. Materials and Methods: Theextracellular endoxylanase was purified using ammonium sulphate fractionation, DEAE anion exchange, and Sephacryl gel filtration chromatography. The enzymatically produced XOS was used in the preparation of XOS syrup adopting the method of ultrafiltration with 10 and 3 kDa molecular weight cut-off (MWCO) membranes. Culture-dependent technique for the bacterial enumeration using selective probiotic microorganisms in an in vitro analysis was employed to confirm the prebiotic nature of XOS syrup. Results: The molecular mass of the purified xylanase (XylB) was found to be approximately 85 kDa with the optimum pH and temperature of 6.5 and 60 °C, respectively. XylB hydrolyzed the xylan and produced short-chain xylooligosaccharides (XOS). At the end of the two-step ultrafiltration process, the hydrolysate was refined to form XOS syrup (44.4%) consisting of XOS with a degree of polymerization (DP) between 2 and 5, and >5. Among all the tested probiotic strains, Lactobacillus brevis exhibited maximum growth in the presence of 0.5% XOS syrup with a specific growth rate of 1.2 h-1. Conclusion: Through this study, we have identified a method to produce XOS syrup that can be used as an effective prebiotic supplement for the growth of several probiotic strains. Human gut probiotics was used as a model system for in vitro analysis of prebiotic oligosaccharide XOS, but for further confirmation of the prebiotic activity, in vivo feeding studies using animal models are needed to be carried out.
Green Synthesis of Iron and Zinc Nanoparticles from Centella Asiatica, Lawsonia Inermis, Ocimum Tenuiflorum and Assessing their Biological Activity for Wound Healing Properties NP Helen Gracelin Joy M., Saron Merline J., Nambeeswari J., Ganga A., Geetha K.* International Journal of Medical and Pharmaceutical Sciences 2 (5), 252-266 , 2026 2026
Sustainable Mesoporous Silica Nanoparticles from Groundnut Shells for High-Efficiency Cr(VI) Removal: Kinetics, Isotherms and Mechanism Insights K Shalini, K.,* Geetha, K., Mariaamalraj, S., and Thavasilingam Chemical and Biochemical Engineering 39 (4), 203–225 , 2026 2026
Eco‑Friendly Approaches to Azo Dye Removal: The Role of Microbial Azo‑Reductases MS Subashini R, Geetha K, Janasuruthi A, Palanisamy T, Jeevitha K, Vishnu R Applied Biochemistry and Biotechnology 197 (8) , 2025 2025 Citations: 5
Fabrication of stimuli gated nanoformulation for site-specific delivery of thymoquinone for colon cancer treatment–insight into thymoquinone’s improved physicochemical properties JP Sweety, S Sowparani, P Mahalakshmi, N Selvasudha, D Yamini, ... Journal of Drug Delivery Science and Technology 55, 101334 , 2020 2020 Citations: 13
Evaluation of anti rheumatic activity of Piper betle L. (Betelvine) extract using in silico, in vitro and in vivo approaches ST Selvakumar Murugesan, Devibala Ravichandran, Dinesh Kumar Lakshmanan ... Bioorganic Chemistry 103, 104227 , 2020 2020 Citations: 28
Purification of endoxylanase from Bacillus pumilus B20 for production of prebiotic xylooligosaccharide syrup; an in vitro study K Geetha, P Gunasekaran Iranian journal of biotechnology 15 (4), 232 , 2017 2017 Citations: 26
Biotransformation of Various Wastes into a Nutrient Rich Organic Biofertilizer - a Sustainable Approach towards Cleaner Environment SBAA Geetha Karuppasamy, Michael Antony D’Couto Biotechnology for Sustainability Achievements, Challenges and Perspectives 1 … , 2017 2017
Bioconversion of non edible vegetables from market into biofertilizer for crop improvement G Karuppasamy, MA D’Couto, A Achary Journal of Agricultural Science 8 (6) , 2016 2016 Citations: 3
Optimization of nutrient medium containing agricultural waste for xylanase production by Bacillus pumilus B20 PG K. Geetha Biotechnology and Bioprocess Engineering 15 (5), 882-889 , 2010 2010 Citations: 46
Synthesis of bacterial polysaccharides as a limiting factor for biofuel production. RJGP Geetha K, Rajnish KN Bacterial polysaccharides: Current innovations and Future trends. 2, 345-356 , 2009 2009 Citations: 2
Strategies for the improvement of levan and fructooligosaccharides production by Zymomonas mobilis VSKGP Gunasekaran* Advances in Bioprocessing in Food Industry 1, 187-208 , 2007 2007
MOST CITED SCHOLAR PUBLICATIONS
Optimization of nutrient medium containing agricultural waste for xylanase production by Bacillus pumilus B20 PG K. Geetha Biotechnology and Bioprocess Engineering 15 (5), 882-889 , 2010 2010 Citations: 46
Evaluation of anti rheumatic activity of Piper betle L. (Betelvine) extract using in silico, in vitro and in vivo approaches ST Selvakumar Murugesan, Devibala Ravichandran, Dinesh Kumar Lakshmanan ... Bioorganic Chemistry 103, 104227 , 2020 2020 Citations: 28
Purification of endoxylanase from Bacillus pumilus B20 for production of prebiotic xylooligosaccharide syrup; an in vitro study K Geetha, P Gunasekaran Iranian journal of biotechnology 15 (4), 232 , 2017 2017 Citations: 26
Fabrication of stimuli gated nanoformulation for site-specific delivery of thymoquinone for colon cancer treatment–insight into thymoquinone’s improved physicochemical properties JP Sweety, S Sowparani, P Mahalakshmi, N Selvasudha, D Yamini, ... Journal of Drug Delivery Science and Technology 55, 101334 , 2020 2020 Citations: 13
Eco‑Friendly Approaches to Azo Dye Removal: The Role of Microbial Azo‑Reductases MS Subashini R, Geetha K, Janasuruthi A, Palanisamy T, Jeevitha K, Vishnu R Applied Biochemistry and Biotechnology 197 (8) , 2025 2025 Citations: 5
Bioconversion of non edible vegetables from market into biofertilizer for crop improvement G Karuppasamy, MA D’Couto, A Achary Journal of Agricultural Science 8 (6) , 2016 2016 Citations: 3
Synthesis of bacterial polysaccharides as a limiting factor for biofuel production. RJGP Geetha K, Rajnish KN Bacterial polysaccharides: Current innovations and Future trends. 2, 345-356 , 2009 2009 Citations: 2
Green Synthesis of Iron and Zinc Nanoparticles from Centella Asiatica, Lawsonia Inermis, Ocimum Tenuiflorum and Assessing their Biological Activity for Wound Healing Properties NP Helen Gracelin Joy M., Saron Merline J., Nambeeswari J., Ganga A., Geetha K.* International Journal of Medical and Pharmaceutical Sciences 2 (5), 252-266 , 2026 2026
Sustainable Mesoporous Silica Nanoparticles from Groundnut Shells for High-Efficiency Cr(VI) Removal: Kinetics, Isotherms and Mechanism Insights K Shalini, K.,* Geetha, K., Mariaamalraj, S., and Thavasilingam Chemical and Biochemical Engineering 39 (4), 203–225 , 2026 2026
Biotransformation of Various Wastes into a Nutrient Rich Organic Biofertilizer - a Sustainable Approach towards Cleaner Environment SBAA Geetha Karuppasamy, Michael Antony D’Couto Biotechnology for Sustainability Achievements, Challenges and Perspectives 1 … , 2017 2017
Strategies for the improvement of levan and fructooligosaccharides production by Zymomonas mobilis VSKGP Gunasekaran* Advances in Bioprocessing in Food Industry 1, 187-208 , 2007 2007
Publications
Geetha Karuppasamy, Michael Antony D’Couto & Anant Achary, Bioconversion of non edible vegetables from market into biofertilizer for crop improvement. Journal of Agricultural Science, Vol. 8, no. 6; pp71-83, May 2016.
DOI:10.5539/