@article {2603, title = {Green-Synthesized Copper Nanoparticles from Azadirachta Indica for Antimicrobial Applications and Potential Visible-Light- Assisted Organic Load Reduction of POME}, journal = {Pharmacognosy Journal}, volume = {18}, year = {2026}, month = {June 2026}, pages = {129-138}, type = {Original Article}, chapter = {129}, abstract = {

Objective: Palm Oil Mill Effluent (POME) is a high-strength agro-industrial wastewater of serious environmental concern due to its high organic load and microbial contamination. Methods: Copper nanoparticles (CuNPs) were synthesized using Azadirachta indica (neem) leaf extract and copper sulfate at different extract-to-metal salt ratios (1:1 and 2:1). The formation of CuNPs was confirmed by color change, FESEM, and EDX analyses. POME samples were collected from two treatment stages (raw and acidification ponds), and bacteria were isolated and identified using morphological, Gram staining, and biochemical tests. The antimicrobial activity of CuNPs at two concentrations (0.008 g and 0.016 g) was evaluated against isolated bacterial strains (Bacillus spp., Pseudomonas spp., and Stenotrophomonas spp.) using the agar well diffusion method. Results: The synthesized CuNPs ranged from 11{\textendash}40 nm in size, confirming the presence of elemental copper with bioorganic capping. Antibacterial activity increased with CuNP loading, with the maximum inhibition zone (50 mm) observed for Bacillus spp. using CuNPs synthesized from a 0.1 M precursor solution and 0.016 g nanoparticle dose. At higher precursor concentrations (1.0 M), aggregation of nanoparticles occurred, leading to reduced antibacterial efficiency. Neem-CuNPs therefore demonstrated strong antimicrobial (disinfection) activity, while photocatalytic effects were observed as a secondary, light-assisted reduction of organic content rather than direct biodegradation. Conclusion: The green-synthesized CuNPs offer an eco-friendly and effective antimicrobial strategy for managing POME-associated bacteria. These findings provide a basis for future work combining CuNPs with biological systems to enhance wastewater remediation.

}, keywords = {Antimicrobial activity, Azadirachta indica, Copper nanoparticles, Disinfection, Green synthesis, Wastewater treatment}, doi = {10.5530/pj.2026.18.126}, author = {Anu Avudaiappan and Krittika Chandran and Sajna Keeyari Purayil and Abiramy Krishnan and Maimuna Gai and Aishath Aala Rasheed and Soh Lee May and Nur Izzah Bt Tohar and Jamal Moideen Muthu Mohamed} } @article {878, title = {In vivo Toxicopathological Evaluation of a Purified Bioflocculant Produced by Arthrobacter humicola}, journal = {Pharmacognosy Journal}, volume = {11}, year = {2019}, month = {May 2019}, pages = {486-492}, type = {Original Article}, chapter = {486}, abstract = {

Introduction: In spite of the commendable flocculating activities of microbial flocculants, a good number of them potentiate significant toxicity. This study evaluated the in vivo toxicological implications of treatment with the Purified bioflocculant (PB) from Arthrobacter humicola using OECD guidelines. Materials and Methods: In the acute toxicity assessment, a single oral administration of 2000 mg/kg body weight (b.w.) of PB was given to the Wistar rats and the animals were observed for 2 weeks. The daily dose toxicity testing was performed through daily oral treatment with graded doses (50, 200 and 500 mg/kg b.w.) of PB for 4 weeks. Clinical signs of toxicity, behavioral changes, hematological and biochemical parameters were thereafter evaluated. Results: PB at 2000 mg/kg b.w. produced no treatment-mediated signs of toxicity, behavioral changes or mortality in the animals. Thus, its no-observed-adverse-effect level was estimated to be above 2000 mg/kg b.w. In the repeated dose toxicity testing, treatments with PB also revealed no significant differences in the feeding patterns, lipid profiles, hematological and clinical biochemistry parameters when compared with the control group. Although, at 500 mg/kg b.w. PB, a significant increase was observed in the serum activities of alkaline phosphatase, nonetheless, cage side observations recorded no treatment-induced signs of toxicity and macro-histopathological examinations of all the investigated organs also revealed no obvious morphological changes. Conclusion: The overall results suggested that PB was well tolerated by the animals and is endowed with monosaccharides bearing functional groups of flocculation importance, thus, suggesting its potential application as a safe actinomycetes bioflocculant for water treatment.\ 

}, keywords = {Actinomycetes, Arthrobacter humicola, Bioflocculant, Hematological, Polysaccharides, Wastewater treatment}, doi = {10.5530/pj.2019.11.77}, author = {Mayowa Oladele Agunbiade and Sabiu Saheed and Esta Van Heerden and Carolina Henritta Pohl} }