Asian Journal of Biotechnology and Genetic Engineering

Comparative Phytochemical Composition and Antibacterial Activity of Selected Medicinal and Aromatic Plant Extracts

2026-07-08T09:06:20+00:00

Background: Medicinal and aromatic plants are important sources of secondary metabolites with potential antibacterial properties.

Aim: This study compared the phytochemical composition and antibacterial activity of ethanolic extracts from seven plant materials: Hibiscus rosa-sinensis L., Tagetes erecta L., Rosa indica L., Eucalyptus globulus L., Cymbopogon citratus DC., Citrus limon L., and Citrus sinensis L.

Method: Extracts prepared from petals, leaves, and citrus fruit peels were subjected to qualitative phytochemical screening and quantitative estimation of total phenolic, tannin, flavonoid, and alkaloid contents. Antibacterial activity was evaluated against Staphylococcus aureus and Escherichia coli by agar well diffusion.

Results: Qualitative tests indicated that alkaloids, carbohydrates, flavonoids, phenolic compounds, tannins, saponins, and carboxylic acid-containing compounds were present in most or all extracts. Quantitative results varied among species. Eucalyptus globulus had the highest total phenolic content (45.06 mg GAE/g) and tannin content (12.28 mg GAE/g), Tagetes erecta had the highest flavonoid content (24.9%), and Citrus limon had the highest alkaloid content (28.7%). All extracts inhibited both bacterial species. Eucalyptus globulus produced the largest inhibition zones, 36.0 ± 3.46 mm against S. aureus and 31.3 ± 3.05 mm against E. coli.

Conclusion: The selected plants contained diverse phytochemicals, and Eucalyptus globulus showed the strongest antibacterial activity under the experimental conditions used.

Ovaprim Dosage Optimization for Spawning Induction of G6 Transgenic Mutiara Catfish

2026-06-06T09:55:41+00:00

Background: Optimization of Ovaprim dosage is necessary to improve spawning success in sixth-generation (G6) transgenic Mutiara catfish carrying the Clarias gariepinus growth hormone (CgGH) gene, whose reproductive performance has not yet been comprehensively evaluated despite stable transgene inheritance and superior growth traits.

Aims: This study aims to determine the optimal dose of Ovaprim hormone for the success of semi-artificial spawning induction of sixth generation (G6) transgenic Mutiara catfish broodstock based on reproductive parameters including relative fecundity, egg diameter, fertilization rate (FR), hatching rate (HR), and survival rate (SR).

Study Design: The study used an experimental method with a Completely Randomized Design (CRD) consisting of four treatments and three replications.

Place and Duration of Study: The study was conducted at Hatchery Building 4, Faculty of Fisheries and Marine Sciences, Padjadjaran University, from July 2025 to March 2026.

Methodology: The study used 32 G6 transgenic Mutiara catfish broodstock, consisting of 16 males and 16 females. The treatments consisted of varying doses of the Ovaprim hormone: Treatment A (0.2 mL/kg male broodstock + 0.6 mL/kg female broodstock), B (0.3 mL/kg + 0.3 mL/kg), C (0.4 mL/kg + 0.4 mL/kg), and D (0.5 mL/kg + 0.5 mL/kg). Observed parameters included relative fecundity, egg diameter, FR, HR, and SR. Data were analyzed using one-way ANOVA followed by Duncan's test using SigmaPlot 16.0 software.

Results: The results showed that the treatments had a highly significant effect (P<0.05) on all reproductive parameters. The highest relative fecundity value was obtained in Treatment D, at 130,303 eggs/kg broodstock, but no improvement was observed in other parameters. Meanwhile, treatment C produced a fecundity of 85.00 eggs/kg, an egg diameter of 1.36 ± 0.14 mm, the highest fertilization rate of 92.39%, a hatching rate of 90.75%, and a survival rate of 85.32%. Duncan's test results showed that treatment C produced higher spawning parameter test results than the other treatments.

Conclusion: The Ovaprim dose of 0.4 mL/kg male broodstock weight and 0.4 mL/kg female broodstock weight is the most optimal dose for semi-artificial spawning induction in G6 transgenic mutiara catfish because it produces the highest fertilization rate, hatching rate, and survival rate. Excessive Ovaprim doses (more than 0.5 ml/kg) cause excessive egg maturation resulting in micropylar blockage and reducing the ability of sperm to fertilize eggs, while low doses (suboptimal) are considered unable to stimulate gonadotropin release optimally so that the final oocyte maturation process does not occur perfectly.

Synthesis, Spectral Characterization, and Molecular Docking Studies of a Novel Au (III) Complex with a Bis-Azo Dye Ligand: Evaluation of its Potential as an Antioxidant and Anti-breast Cancer Agent

2026-06-10T09:13:13+00:00

The development of metal-based therapeutics remains a cornerstone of modern medicinal chemistry. In this study, a novel Au (III) complex was synthesized using the heterocyclic bis-azo dye ligand 2,2-[1,1'-(1,1')-Dimethylphenyl azo]-bis-benzylphenol (O-TPAN). Characterization via 1H-NMR, UV-Vis, FT-IR, XRD, and SEM confirmed a [M2(L)2Clx] stoichiometry, suggesting an octahedral coordination environment where the ligand acts as bidentate through the azo nitrogen and phenolic oxygen. Antioxidant evaluation using the phosphomolybdate assay demonstrated that the Au (III) complex exhibits superior radical scavenging activity compared to the free ligand, rivaling ascorbic acid. Furthermore, MTT assays against the MCF-7 breast cancer cell line revealed significant dose-dependent cytotoxicity (IC50 = 114.0 µg/mL) with high selectivity, as evidenced by minimal toxicity toward normal human dermal fibroblasts (HdFn). Molecular docking simulations with protein kinase (1HK7) further elucidated the binding mechanisms, positioning this complex as a potent candidate for targeted breast cancer therapy.

Prevalence, Virulence Genes, and Antimicrobial Susceptibility Profile of Staphylococcus spp. Isolated from Pet Dogs and Cats in Al-Muthanna Governorate, Iraq

2026-07-03T07:43:13+00:00

Companion animals can harbour pathogenic and antibiotic-resistant Staphylococcus species, posing a public health risk because of their close contact with humans. This study investigated the prevalence, virulence genes and antimicrobial susceptibility of Staphylococcus species isolated from pet dogs and cats in Al-Muthanna Governorate, Iraq. From October 2025 to May 2026, nasal swabs were collected from 1,057 clinically healthy pets (630 dogs and 427 cats). Isolates were identified using biochemical methods and the VITEK-2 Compact system. Multiplex PCR was used to screen 433 Staphylococcus isolates for five virulence genes (luk-PV, ebpS, tsst-1, fib and hlg), and susceptibility to 15 commonly used antibiotics was evaluated. Staphylococcus species were isolated from 41.0% (433/1,057) of the animals, with a higher prevalence in dogs (47.0%, 296/630) than in cats (32.1%, 137/427). Staphylococcus aureus was the predominant species among the screened isolates (201 isolates), followed by S. epidermidis (105), S. capitis (65), S. hominis (44) and S. lugdunensis (26). Virulence genes were widespread, especially in S. aureus, which frequently carried ebpS (90.0%), luk-PV (88.6%), tsst-1 (80.6%), hlg (64.2%) and fib (52.2%). Across all species, high resistance to methicillin and penicillin G was observed, whereas resistance to gentamicin, cephalothin, gatifloxacin, ciprofloxacin and enrofloxacin remained low. These findings indicate that pet dogs and cats in Al-Muthanna Governorate harbour diverse Staphylococcus species with virulence potential and antimicrobial resistance, supporting the need for surveillance and responsible antimicrobial use.

Development of Chitosan Silver Nanobiocomposites for Antimicrobial Food Packaging Applications

2026-07-04T06:20:21+00:00

Aim: This study developed and evaluated chitosan–silver nanobiocomposite films for antimicrobial food-packaging applications.

Methodology: Chitosan obtained from shrimp shell waste was used as the biopolymer matrix, and silver nanoparticles (AgNPs) were incorporated at 6 wt.% and 15 wt.% through in situ synthesis followed by solution casting. The films were characterised using UV–visible spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. Bread and fresh meat samples were packaged with the developed films, and microbial loads were monitored during five days of storage.

Results: UV–visible spectra showed a characteristic surface plasmon resonance band at approximately 410–420 nm, indicating successful AgNP formation. FTIR analysis showed interactions between AgNPs and amino and hydroxyl groups in chitosan, while SEM observations indicated more uniform nanoparticle dispersion at lower AgNP loading and increased surface roughness at higher loading. In the food-packaging test, chitosan–AgNP films reduced microbial growth compared with untreated controls. By day 5, bread packaged with the nanobiocomposite film showed 1.0 × 10⁵ CFU compared with 3.0 × 10⁶ CFU in the control, while meat showed 1.5 × 10⁵ CFU compared with 3.0 × 10⁶ CFU in the control.

Conclusion: The results indicate that chitosan–AgNP films can suppress microbial proliferation in bread and meat models and may be suitable for further development as biodegradable active packaging materials.

Biological Activities of Phytogenic Fe-Mn Nanoparticles Synthesized Using Mangifera indica Leaf Extract

2026-07-11T12:10:10+00:00

Antimicrobial resistance and oxidative stress-related disorders have increased the need for multifunctional bioactive materials. This study synthesised iron-manganese (Fe-Mn) bimetallic nanoparticles using aqueous Mangifera indica leaf extract and evaluated their antibacterial and antioxidant activities. Fe-Mn nanoparticles were prepared by mixing aqueous Fe²⁺ and Mn⁷⁺ salt solutions with M. indica leaf extract. The synthesised nanoparticles were characterised using UV-Visible and Fourier-transform infrared spectroscopy. Antibacterial activity was assessed by agar well diffusion, minimum inhibitory concentration and minimum bactericidal concentration assays against Escherichia coli, Salmonella typhi, Klebsiella pneumoniae and Pseudomonas aeruginosa. Antioxidant activity was determined using DPPH and ABTS radical scavenging assays. UV-Visible analysis showed a surface plasmon resonance peak at 450 nm, while FTIR analysis indicated functional groups including O-H, C=O and Fe-O/Mn-O, suggesting nanoparticle formation and phytochemical involvement in reduction and stabilisation. The nanoparticles produced inhibition zones of 15.00 mm against S. typhi, 14.90 mm against K. pneumoniae, 14.83 mm against E. coli and 7.13 mm against P. aeruginosa. The MIC was 12.5 µg/mL for all tested organisms, while MBC values ranged from 25 to 50 µg/mL. In the DPPH assay, Fe-Mn nanoparticles showed 28.25% inhibition at 6.25 µg/mL and an IC₅₀ of 23.74 µg/mL. In the ABTS assay, maximum inhibition was 51.65% at 60 µg/mL. The findings indicate preliminary antibacterial and antioxidant potential under the tested laboratory conditions.

Agricultural Biotechnology for Climate-Resilient Farming Systems in Odisha, India: Advances, Field Evidence and Future Strategies

2026-06-04T08:15:26+00:00

Agriculture in Odisha is highly vulnerable to climate variability, including floods, droughts, cyclones, salinity intrusion and rising temperature stress, which significantly affect crop productivity and livelihood security. In this context, agricultural biotechnology has emerged as an important approach for developing climate-resilient and sustainable farming systems. This review examines recent advancements in agricultural biotechnology and their relevance to Odisha’s agro-ecosystems.

The review summarizes biotechnology-based interventions such as stress-tolerant crop varieties, biofertilizers, biopesticides, marker-assisted selection, CRISPR-based genome editing and AI-assisted precision agriculture. Field-level evidence from Odisha and eastern India indicates that submergence-tolerant rice varieties improve yield stability under flood conditions, while millet-based systems integrated with microbial biofertilizers enhance productivity and farmer income in drought-prone regions. The review further discusses the role of microbial biotechnology, digital agriculture and integrated climate-smart farming approaches in improving soil health, nutrient-use efficiency and environmental sustainability.

The study also highlights major constraints limiting biotechnology adoption, including inadequate awareness, weak extension services, fragmented landholdings and limited access to quality bio-inputs. A brief literature-based review methodology and current limitations of available regional data are considered in the analysis. Overall, the review concludes that location-specific and farmer-centered biotechnology interventions, supported by policy integration and institutional strengthening, can significantly contribute to climate-resilient and sustainable agricultural development in Odisha and other climate-vulnerable regions.

Harnessing Plant Antimicrobial Peptides for Crop Protection: From Molecular Defence Mechanisms to Peptide Engineering and Field Applications

2026-07-08T11:00:23+00:00

Plant pathogens destroy a substantial share of global crop production every year, and reliance on conventional agrochemicals is increasingly constrained by resistance evolution, residue regulation and environmental concern. Antimicrobial peptides synthesised by plants as part of their innate immune repertoire offer an alternative route to durable disease control. These small, predominantly cationic and cysteine-rich molecules fall into several structurally distinct families, including defensins, thionins, lipid transfer proteins, snakins, cyclotides and hevein-like peptides, each combining membrane-permeabilising activity with, in many cases, additional intracellular or signalling functions. This review synthesises current understanding of the molecular architecture and mechanisms of action of plant antimicrobial peptides, their integration with pattern-triggered and effector-triggered immune signalling, and the principal strategies used to engineer them for improved potency, stability and selectivity, including rational design, recombinant and transient expression platforms, genome editing and computational discovery pipelines. Approaches for translating these molecules into field-deployable products are examined, spanning transgenic and cisgenic expression, viral-vector-mediated transient expression, nanocarrier-assisted foliar delivery and postharvest application, together with documented cases of disease resistance achieved in model and crop species. Persistent obstacles, including proteolytic instability, high production cost, regulatory uncertainty for genetically modified and gene-edited crops, and limited field-scale validation, are discussed alongside emerging solutions. The review concludes that plant antimicrobial peptides represent a scientifically mature but commercially underexploited resource, and that further progress depends on closer integration of structural biology, synthetic biology and agronomic trial design.