Asian Journal of Biotechnology and Bioresource Technology

Exploring Nanoparticle-based Approaches to Improve Semen Freezability in Domestic Animals

Fri, 26 Jun 2026 00:00:00 +0000

Semen cryopreservation is an indispensable tool in animal reproductive biotechnology, supporting long-term genetic conservation, artificial insemination, selective breeding and livestock improvement programmes. However, the freeze-thaw process can induce substantial cryoinjury in spermatozoa through oxidative stress, osmotic imbalance, membrane destabilisation, mitochondrial dysfunction and DNA damage, thereby reducing post-thaw sperm quality and fertilising capacity. Conventional cryoprotectants and antioxidants incorporated into extenders before processing provide partial protection, but their efficacy may be limited by low stability, inadequate cellular penetration, batch variability and inconsistent responses among species. Nanotechnology has therefore emerged as a complementary strategy for improving antioxidant delivery, membrane protection and controlled release of bioactive compounds during semen preservation. This review summarises the mechanisms of sperm cryoinjury and evaluates nanoparticle-based approaches used to mitigate freeze-thaw-induced damage in domestic animals. The discussion is restricted to evidence presented in the manuscript and focuses on reproductive applications relevant to semen freezability. Reported nanoparticle systems include selenium, zinc oxide, cerium oxide, iron oxide, gold and silver nanoparticles, nano-emulsions, liposomes, nano-lecithin, polymeric carriers and phytochemical-based nano-formulations. These additives have been associated with improvements in sperm motility, viability, membrane integrity, acrosome status, mitochondrial activity, antioxidant balance and, in selected studies, fertility-related outcomes. Species-specific responses in bovine, caprine, ovine, equine, canine and swine spermatozoa are also considered, as variations in membrane composition and antioxidant capacity influence freezability and nanoparticle efficacy. The review further discusses dose-dependent nanotoxicity, biosafety concerns, reproductive risks and the need for careful physicochemical characterisation. Current evidence indicates that nanoparticle-assisted cryopreservation has practical potential, provided that protocols are optimised for each species and supported by long-term safety and fertility validation.

Nanotechnology Applications for Oil Spill Remediation in Sub-Saharan Africa: A Critical Review of Mechanisms, Constraints, and Prospects

Mon, 06 Jul 2026 00:00:00 +0000

Oil spillage remains one of the most persistent and under-addressed environmental hazards confronting Sub-Saharan Africa, with the Niger Delta standing as the most heavily documented but by no means the only affected region. Decades of pipeline vandalism, ageing infrastructure, illegal refining and operational discharges have left mangrove forests, farmland and freshwater systems contaminated with petroleum hydrocarbons, with consequences that extend into fisheries collapse, soil infertility and chronic human exposure to carcinogenic compounds. Conventional remediation methods, including mechanical skimming, in-situ burning, chemical dispersants and unassisted bioremediation, have shown only partial success in this setting, constrained by cost, slow degradation kinetics, secondary pollution and limited applicability to the region's swamp and estuarine terrain. Nanotechnology has, over roughly the last fifteen years, emerged as a complementary set of tools capable of addressing several of these shortcomings through magnetic nanosorbents, carbon-based and biopolymer adsorbents, nanoparticle-enhanced bioremediation, photocatalytic degradation and nanostructured dispersants. This review synthesises the peer-reviewed literature on these nanomaterial classes, evaluates the mechanisms by which they intensify oil recovery and degradation, and critically examines the structural, economic, regulatory and socio-cultural conditions that will determine whether such technologies can be meaningfully deployed across Sub-Saharan Africa. Particular attention is given to the trade-offs between recovery efficiency and ecological safety, given that the toxicological profile of many engineered nanomaterials remains incompletely characterised in tropical aquatic and soil systems. The review concludes that nanotechnology offers genuine, if currently uneven, promise for the region, contingent on locally adapted material design, strengthened institutional capacity, and the establishment of risk-governance frameworks suited to resource-constrained settings.

From Ancient Pastures to Modern Genetics: The History, Breeding Systems, and Improvement Programmes of Sheep in India's Arid North-West

Shruti Gupta, Sanchit Pal Singh, Rohit Solanki, Vivek Singh, Amritanshu Upadhyay — Fri, 17 Jul 2026 00:00:00 +0000

The arid and semi-arid tracts of north-western India, spanning Rajasthan, Kutch, and adjoining parts of Gujarat and Haryana, have supported extensive sheep husbandry for millennia, giving rise to a remarkable assemblage of indigenous breeds adapted to heat, water scarcity, and sparse forage. This review traces the historical and cultural foundations of sheep keeping in this region, principally through the migratory pastoralism of communities such as the Raika and Rabari, before examining the morphological, productive, and genetic characteristics of the principal breeds of the tract, including Marwari, Chokla, Magra, Nali, Jaisalmeri, Malpura, Sonadi, and Patanwadi. It considers the physiological and molecular basis of thermotolerance and aridity adaptation in these populations, the institutional history of organised breeding and crossbreeding programmes centred on the Central Sheep and Wool Research Institute, and the contribution of pedigree-based and genomic approaches to understanding inbreeding, genetic diversity, and selection response. The socio-economic context of wool production, disease burden, and shrinking common grazing resources is discussed alongside emerging community-based and genomic breeding strategies drawn from comparable dryland systems elsewhere. The review closes by identifying priority directions for research and policy, summarising the principal conclusions of the synthesis, and setting out the methodological limitations inherent in a narrative review of this kind. The tract's sheep genetic resources, forged over centuries of pastoral selection, are shown to represent both a productive asset and a repository of adaptive variation whose conservation carries consequences well beyond the region itself.

Response of Organic Fertilizer on Different Varieties of Okra for Growth and Yield Traits

Adewusi, O.F — Wed, 27 May 2026 00:00:00 +0000

Okra is generally a self-pollinating crop belonging to the family Malvaceae. The increasing global demand for okra necessitates improved cultivation practices to enhance yield, quality and sustainability that can actually sustain the teeming, growing populace. This study was carried out on the “Evaluation of different organic fertiliser sources on agronomic growth performance and yield in okra varieties Abelmoschus esculentus (L) Moench. The study aimed to determine the effect of moringa leaf extract, cow dung, bio-fertiliser and the combined organic fertilisers on agronomic growth performance and yield of okra varieties. The fifteen okra varieties utilised for this study were obtained from the okra germplasm collection at the National Centre for Genetic Resources and Biotechnology (NACGRAB), Department of Plant Genetic Resources, Ibadan, Oyo State, Nigeria. The experiment was a pot experiment whereby the okra varieties were subjected to 5 treatments, which comprise Treatment 1 (Control), Treatment 2 (Moringa leaf extract), Treatment 3 (Cow dung), Treatment 4 (Bio-fertiliser) and Treatment 5 (Combined fertiliser application). The experiment was carried out at the Teaching and Research Farm, Obakekere, Federal University of Technology, Akure. Data were collected on twelve agronomic characters. The application of combined fertiliser was found to greatly influence the rate of growth and yield of the okra varieties, followed by application of bio-fertiliser, followed by application of moringa leaf extract and application of cow dung for all the characters studied. Varieties NGB00466, NGB00380, NGB00322, NGB00305, NGB00342 and NGB00323 were found to be outstanding in terms of number of fruits, total fruit yield and individual fruit weight, irrespective of the type of fertiliser applied. Variety NGB00380 recorded the highest number of fruits. The study shows that the use of organic fertilizer in crop production is desirable as it has a variable impact on the growth and yield of okra and also improve soil organic status, it is also inexpensive, environmentally safe and will not in any way has adverse effect on human health due to the fact that there is no likelihood of any residual property of the organic fertilizer in the crop being used for the production. It can also be shown clearly that the unnecessary additional cost incurred in the cost of the production of okra because of spending on inorganic fertiliser can be eliminated or avoided by solely utilising organic manure from plant and animal sources for okra production.

Physicochemical and Nutritional Characterization of a Post-Operative Beverage Formulated with Rice Milk, Soy Milk, Doum Extract and Lemon Juice Harvested from Benoué Valley in Cameroon

Junias Paki, Charles Touwang, Jean Paul Bayang, Pierre Biyanzi — Tue, 02 Jun 2026 00:00:00 +0000

Liquid diets are used temporarily after illness or surgery to provide easily absorbable nutrients, maintain hydration, and support recovery, but they may lack sufficient protein, fiber, and micronutrients if poorly balanced. In northern Cameroon, many postoperative patients cannot access commercial nutritional products, leaving families to manage nutrition without adequate knowledge of high-quality liquid diets. The objective of this study was to formulate a liquid food with high nutraceutical potential using rice (Oriza sativa) milk, soy (Glycine max) milk, doum (Hyphaene thebaïca) extract, and lemon (Citrus limon) juice. Twelve porridges were formulated using a simplex design with constraints. The physicochemical profiles of the most popular beverages and a traditional porridge (BT) regularly consumed were compared. The results show that porridges B12 (45%, 35%, 10%, 10%) and B6 (40%, 30%, 20%, 5%) were the most accepted. Significant differences (p < 0.05) were observed between the measured parameter values. The BT porridge stood out with a pH of 2.5, while porridges B12 and B6 had pH values of 5.5 and 5, respectively. The B12 mixture had higher levels of protein (9.48±0.08%), carbohydrates (37.01±0.01%), and fat (6.25±0.6%), with an energy value of 245.23±7.56 kcal/100 ml. Similarly, its Ca and Mg contents were the highest, at 66.02 ± 0.07 mg/100 g and 22.99 ± 0.08 mg/100 g, respectively. Porridge B6 showed higher levels of vitamin A (3.06±0.02 μg RE/100 g) and vitamin C (16.87±0.05 μg EAA/100 g). The B12 beverage stood out for its higher polyphenol (184.17 ± 2.61 mgEAG/100g) and tannin (8.87 ± 0.05 mgEC/100g) content compared to those of B6 and BT. The flavonoid content, however, was highest in B6 at 54.46 ± 0.46 mgE/100g. Drinks B12 and B6 appear to be sources of essential nutrients and bioactive compounds. Optimizing the ratio of the various components is necessary to improve nutrient absorption while preserving the antioxidant and functional properties of the formulated drinks.

Fermented Fruit Peels for Sustainable Biotechnological Applications

Aminu Argungu Umar, Isah Musa Fakai, Ibrahim Shehu, Zainab Saidu Salah — Thu, 11 Jun 2026 00:00:00 +0000

A new and environmentally viable approach towards recycling fruit waste is the valorisation through fermentation that could yields a multipurpose liquid called eco-enzyme (EE) or garbage enzyme. This study aimed to provide an insight on the multienzyme, antibacterial and antioxidant potentials of fermented fruit peels solutions produced using pineapple, orange, and watermelon peels. To achieve this, each of the pineapple, orange, and watermelon peels were fermented individually by mixing with water and brown sugar in a ratio of 3:1:10 (fruit peel: brown sugar: water) for 3 months. After 3 months of fermentation, the solutions were filtered and evaluated for their enzymatic, antibacterial, and antioxidant attributes. All the Eco-enzyme solutions exhibited amylase, cellulase, pectinase and protease enzyme activities. Also, all the eco-enzyme solutions inhibited the growth of all the test bacteria, with pineapple peel-derived eco-enzyme solution being the most active in inhibiting the growth of all the tested bacterial strains. All the eco-enzyme solutions produced in this study, showed strong antioxidant properties of 73.21%, 69.37%, 60.09%, and 82.71 for pineapple peels eco-enzyme solution, orange peel eco-enzyme solution, watermelon peels eco-enzyme solution, and mixed fruit peels eco-enzyme solution respectively at 100 ppm. Mixed fruit peels eco-enzyme solution showed the highest amylase activity of 38.75 U/mL, orange peel eco-enzyme has the highest cellulase and pectinase activities of 61.26 U/mL and 62.15 U/mL respectively. Pineapple peel eco-enzyme has the highest protease activity of 79.29 U/mL. Also, all the eco-enzyme solutions inhibited the growth of all the test bacteria, with Staphylococcus aureus exhibiting more sensitivity to all the eco-enzyme solutions compared to other tested bacterial strains. The zone of inhibitions observed against Staphylococcus aureus 18±0.12, 21±0.23, and 19±0.15 for pineapple peels eco-enzyme solution, orange peel eco-enzyme solution, and watermelon peels eco-enzyme solution respectively. The fermented solutions exhibited multienzyme potentials, broad-spectrum antibacterial potential, and significant antioxidant activities. These results suggest that solutions from fermented pineapple, orange, and watermelon peels are interesting areas for further research due to their exhibited attributes.

Pink Shrimp Chitosan: A Cutting-edge Sustainable and Low Cost Alternative against Clinical Multidrug Resistant Isolates

Sat, 13 Jun 2026 00:00:00 +0000

Therapeutic failures and the ever-increasing costs of treating resistant bacterial infections are prompting a search for alternative treatments. The present study was initiated to evaluate the antibacterial activity of chitosan extracted from pink shrimp exoskeleton on multi-resistant bacteria strains collected in hospitals. The chitosan was extracted from pink shrimp collected at Douala using the chemical method and characterized using its degree of deacetylation and FTIR. Its antimicrobial activity was assessed by the agar diffusion method for qualitative evaluation, and by the liquid macro-dilution method for quantitative evaluation. 230 isolates were collected from hospitals, identified at the phenotypic level and their antibiotic sensibility profile was determined using the disc diffusion method. The antimicrobial activity of chitosan was tested on selected multiple-resistant antibiotic isolates using well diffusion and microdilution methods. The results showed a yield of 2 % of chitosan with a degree of deacetylation of 75 %. The IR spectrum obtained was superimposable on that of the standard. A total of 230 strains were identified and grouped into 19 bacterial genera. Ten isolates displayed the highest resistance profile to the tested antibiotics. Chitosan was active against these multiple antibiotic resistant isolates with inhibition diameter ranging from 9 to 30 mm. The MIC of chitosan was between 10 and 160µg/mL with Gram positive bacteria being more sensitive. Chitosan was bactericidal against 69 % of the total strains while Serratia macerans (6%) and Citrobacter freundii (1%) were the most resistant. This study demonstrates the antimicrobial activity of chitosan against clinical multiple antibiotic resistant isolates and suggests its potential use as a sustainable alternative against the growing burden of antimicrobial resistance.

Exploring the Ethnobotanical Properties of Bombax buonopozense and Evaluating Sauces Made with its Calyces in the District of Bas-Sassandra, Côte d'Ivoire, through Sensory Evaluation

Sat, 27 Jun 2026 00:00:00 +0000

This study examined ethnobotanical knowledge of Bombax buonopozense and the sensory characteristics and acceptability of sauces prepared from its calyces in the District of Bas-Sassandra, Côte d'Ivoire. An ethnobotanical survey was conducted from March to April 2024 in the departments of Divo, Lakota and Guéyo, with 384 respondents selected in locations where the species was reported to be abundant. Information was collected on knowledge of the tree, calyx acquisition, uses, consumption, conservation and marketing, together with respondents' socio-demographic characteristics. Fresh flowers were collected in Guéyo, and calyces were separated, washed and used either fresh or after oven drying, grinding and sieving. Sauces prepared from fresh and dried calyces were assessed by 12 trained panellists for sensory profiling and by 60 untrained panellists for acceptability using a 9-point hedonic scale. All respondents knew Bombax buonopozense and reported its presence in the study localities. Calyces were mainly collected fresh under trees (98.8%) and were used for food (65.63%), children's play (33.75%) and, to a lesser extent, medicine (0.63%). Sauce was the only reported food form, and stickiness was identified as its desirable attribute. The calyces were mainly preserved by drying (91.50%). Sensory profiling showed that the sauces had a dark colour, lumpy appearance, bland taste, leafy aroma, no aftertaste, lumpy texture, sticky adhesiveness and leafy odour. Dried-calyx sauce was darker and less elastic than fresh-calyx sauce. In the acceptability test, fresh-calyx sauce received a higher overall appreciation score (6.183/9) than dried-calyx sauce (5.55/9). The findings indicate that Bombax buonopozense calyces are locally known and used, and that fresh-calyx sauce was more acceptable to the panel.

Microplastics and Microbial Contamination in Warri River Surface Waters, Delta State, Nigeria

Odesiri-Eruteyan, Eunice Asiboroko, Enakireru, Bobby Davis — Mon, 29 Jun 2026 00:00:00 +0000

The increasing accumulation of microplastics and microbial contaminants in surface waters has emerged as a significant environmental and public health concern, particularly in regions characterised by inadequate waste management practices, such as the Niger Delta, Nigeria. This study investigated the occurrence, characteristics and associated microbial contamination of microplastics in the surface waters of the Warri River, Delta State, Nigeria. Water samples were collected from five locations along the river and analysed using stereomicroscopy to characterise microplastics based on shape, size and colour. Phthalate esters were quantified using gas chromatography–mass spectrometry (GC–MS), while microbial analyses involved the enumeration and identification of total heterotrophic bacteria, coliforms and fungi using standard microbiological procedures. Microplastics were detected at all sampling locations, with fibres and filaments constituting the predominant particle types. The most abundant size fractions were 0.3–0.1 mm and 1–0.3 mm, indicating extensive fragmentation of larger plastic debris. Black, brown and transparent particles were the most frequently observed colours, suggesting inputs from domestic activities and degraded plastic materials. GC–MS analysis confirmed the presence of phthalate esters, indicating the occurrence of plastic-associated chemical contaminants within the aquatic environment. Total heterotrophic bacterial counts ranged from 5.24 × 10⁶ to 9.10 × 10⁶ CFU mL⁻¹, total coliform counts ranged from 90 to 270 MPN 100 mL⁻¹, and total fungal counts ranged from 2.60 × 10³ to 4.90 × 10³ CFU mL⁻¹ across the sampling locations. Identified microbial isolates included Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Aspergillus spp. and Candida spp., many of which have been reported to possess enzymatic capabilities associated with the degradation of plastic polymers. The findings demonstrate that the Warri River is affected by both microplastic pollution and elevated microbial contamination, posing potential ecological and public health risks to aquatic ecosystems and communities that depend on the river. Strengthening waste management systems, improving wastewater treatment infrastructure and implementing routine environmental monitoring are recommended to mitigate pollution and safeguard environmental quality.

Isolation of Bacteria with Potential to Produce Enzyme Cellulase from Soil Samples

F. O. Ibitoye, T. R. Elehinafe, I. I. Awoyo — Wed, 01 Jul 2026 00:00:00 +0000

The importance of cellulases, one of the most important enzymes in modern industry, cannot be overstated. Bacteria that produce cellulase are significant for sectors such as food, textiles and paper. Therefore, isolating such bacteria from soil samples associated with refuse dump sites is important for several biotechnological applications. This study aimed to isolate and screen cellulase-producing bacteria from soil samples collected from refuse dump sites in Emure Ile-Owo, Ondo State, and to evaluate their ability to degrade carboxymethyl cellulose (CMC) as an indicator of cellulase enzyme production. Soil samples were inoculated on nutrient agar after serial dilution to determine the total colony count. The colony counts showed that the sample from Zone B had the highest number of colonies (3.3 × 10⁵ cfu/g), whereas the sample from Zone C had the lowest number (1.5 × 10⁵ cfu/g). Morphological and biochemical analyses were performed to identify the isolates. The bacteria isolated were Bacillus subtilis, Bacillus cereus, Paenibacillus spp. and Clostridium botulinum. Congo red staining of CMC agar plates inoculated with the isolates was used to test cellulolytic activity. Bacillus cereus, Paenibacillus spp. and Bacillus subtilis were able to hydrolyse carboxymethyl cellulose.

Characterization of the Biometric, Physicochemical, Nutritional, and Bioactive Properties of Cocoa Beans (Theobroma cacao L.) from the Secondary Harvest in the Municipality of Obala (Central Region, Cameroon)

Touwang Charles, Ndih Aimé Christian, Bayang Jean Paul, Lesse Modo Bienvenu — Thu, 09 Jul 2026 00:00:00 +0000

Cocoa (Theobroma cacao L.) is an important export crop in Cameroon, and bean quality strongly influences its technological and industrial value. This study characterised the biometric, physicochemical, nutritional and bioactive properties of cocoa beans obtained from the secondary harvest in the municipality of Obala, Central Cameroon. Beans collected from six plantations were fermented for seven days, sun-dried and analysed using standard physical and biochemical methods. The results showed variability in bean dimensions, with lengths mainly ranging from 2.2 to 2.6 cm, widths from 1.2 to 1.4 cm and thicknesses from 0.5 to 0.6 cm. The bean count was 108 beans per 100 g, indicating medium-sized beans. Dry matter content was high (94.62%), while shell proportion (12.11%) and breakage rate (17.89%) were recorded alongside a cocoa paste yield of 94.80%. Nutritionally, the beans had a pH of 5.83, titratable acidity of 3.48 mg OAE/100 g DM, fibre content of 12.76%, protein content of 16.02% and lipid content of 51.80%. Bioactive compound analysis showed total polyphenols of 1,258 mg GAE/100 g DM, flavonoids of 287.65 mg QE/100 g DM and tannins of 498.72 mg CE/100 g DM. These findings indicate that secondary-harvest cocoa beans from Obala have measurable processing, nutritional and bioactive attributes. Further sensory, aromatic and agronomic evaluations are needed to clarify their quality determinants.

Optimizing the Nutritional, Phytochemical, and Techno-functional Profiles of Pigeon Pea Seed (Cajanus cajan L.) Flour through Spontaneous Fermentation

Naka Toure, Mouhamadou Kebe, Sylvie Assoi, Abdoulaye Toure — Thu, 16 Jul 2026 00:00:00 +0000

Pigeon peas, although they contain two to three times more protein than cereals, are not widely used due to low digestibility, antinutritional properties, and difficult cooking characteristics. This study evaluated the effect of spontaneous fermentation on the nutritional and techno-functional characteristics of pigeon pea seed (Cajanus cajan L.) flour. Pigeon pea seeds obtained from Tanda, Côte d’Ivoire, were sorted, washed and divided into several batches. One batch was used as a control sample, while the rest were allowed to ferment spontaneously in distilled water at room temperature (28 ± 2 °C) for 24, 48 or 72 h. The flours obtained from the different treatments were analyzed for antinutritional factors, total polyphenols, flavonoids, individual phenolic compounds, vitamins and water/oil absorption capacities. The results showed a substantial decrease in tannins, oxalates and phytates after 72 hours of fermentation, which indicates a reduction in the antinutritional factors. The total polyphenol and flavonoid content of the flours varied with fermentation time, with the highest content observed after 72 hours. Furthermore, HPLC analysis revealed that phenolic compounds such as chlorogenic acid, catechin and hydroquinone were the compounds that changed the most in concentration. Fermentation also influenced the vitamin content of the flour, notably increasing the levels of riboflavin (B2) and pyridoxine (B6). A greater water absorption capacity and a lower oil absorption capacity of the pigeon pea seed flour were observed after fermentation. Overall, it was found that spontaneous fermentation modifies the nutritional, phytochemical and functional characteristics of pigeon pea seed flour, which could improve its suitability for use in food formulations. However, further research into the product's safety, digestibility and sensory perception is required before it can be used.

Hygiene Practices and Quality Evaluation of Artisanal Juices from Kaya, Burkina Faso

Fri, 17 Jul 2026 00:00:00 +0000

Aims: This study aimed to assess the quality of artisanal fruit juices produced in Kaya, the capital city of the Kulsé region in Burkina Faso, through an evaluation of production practices and physicochemical and microbiological characterisation.

Design: A cross-sectional experimental study was conducted.

Setting and Duration: The research was carried out in Kaya over three months, from November 1, 2025, to January 31, 2026.

Methodology: Fifteen juice samples (mango, pineapple, hibiscus, tamarind, and ginger) were analysed according to international standards. An audit of hygiene and production practices was performed. Physicochemical parameters (pH, °Brix, titratable acidity) and microbiological indicators (total aerobic mesophilic flora, yeasts and moulds, coliforms, Escherichia coli, Salmonella, and Shigella) were measured.

Results: The audit revealed an overall compliance rate of 80.68%, indicating good adoption of hygiene practices despite weaknesses in facilities and storage. pH values ranged from 3.29 ± 0.01 to 4.47 ± 0.02, consistent with preservation standards. °Brix values varied between 7.95 ± 0.2 and 15.9 ± 0.14, with tamarind showing the highest sugar content and ginger the lowest. Titratable acidity ranged from 0.10% to 0.46%. Microbiological analysis showed moderate aerobic flora in mango, pineapple, and hibiscus juices (6.82 × 10¹ to 4 × 10² CFU/mL), with low yeast and mould counts. Coliforms and E. coli were below 10 CFU/mL. Tamarind and ginger juices showed no detectable microbial load. Salmonella and Shigella were absent in all samples.

Conclusion: Overall, the assessed juices showed physicochemical and microbiological values within the applied criteria. Tamarind and ginger samples had no detectable microbial load under the study conditions; however, their antimicrobial mechanisms were not directly investigated. The identified non-compliances highlight the need to strengthen hygiene practices and quality monitoring.

Molecular Identification, Phylogenetic Characterisation and Conidial Formulation of Emericella nidulans for Mosquito-larvicidal Bioassay

Mon, 20 Jul 2026 00:00:00 +0000

This study confirmed the molecular identity and phylogenetic placement of an entomopathogenic fungal isolate previously identified morphologically as Emericella nidulans and standardised its conidial suspension for subsequent larvicidal evaluation against Anopheles gambiae. Genomic DNA was extracted using the CTAB method and amplified with ITS1/ITS4 primers targeting the ITS region. The amplification produced a single 526 bp band, and the extracted DNA showed a concentration of 52 ng µL⁻¹ with an A₂₆₀/A₂₈₀ ratio of 1.83, indicating purity suitable for PCR. Bidirectional sequencing followed by BLAST analysis showed 98.07% nucleotide similarity to E. nidulans strain IHB F 1876 (GenBank accession MN045781), thereby supporting the morphological identification. Neighbour-joining phylogenetic analysis placed the isolate within the Emericella clade with 99% bootstrap support, and the genetic distance between the isolate and the closest reference strain was 0.021 substitutions per site. Field-collected fourth-instar mosquito larvae were identified morphologically as Anopheles gambiae based on a horizontal resting posture, absence of a respiratory siphon and the presence of palmate hairs on abdominal segments II–VII. Four conidial suspensions were prepared at 9.2 × 10⁴, 9.2 × 10⁵, 9.2 × 10⁶ and 9.2 × 10⁷ conidia mL⁻¹. Viability after 24 hours ranged from 91% to 96%, and mean germination time decreased from 20 to 14 hours as conidial concentration increased. These standardised preparations were therefore suitable for use in planned larvicidal bioassays, although larval mortality was not evaluated in the present work. The findings provide an authenticated molecular, phylogenetic and biological baseline for future mosquito-larvicidal bioassays using E. nidulans metabolites.

Population Dynamics of Certain Insect Pests of Brown-top Millet and Their Natural Enemies

Krishana, S. Amruth, Prabhu C. Ganiger — Fri, 24 Jul 2026 00:00:00 +0000

Browntop millet is an under-researched small millet for which field information on insect pest succession is limited. A two-season observational study was conducted at the Zonal Agricultural Research Station, University of Agricultural Sciences, Bengaluru, during Kharif 2023 and 2024. A 3 × 4 m plot of the variety GPUBT-1 was monitored weekly from 15 days after sowing to harvest. Shoot-fly damage was expressed as dead-heart incidence, while weevils, grasshoppers, aphids, coccinellids, and spiders were recorded using plant-, leaf-, or row-based counts. In 2023, shoot-fly dead-heart incidence increased from 23.67% in the 36th standard meteorological week (SMW) to a maximum of 30.25% in the 38th SMW and then declined to zero by the 44th SMW. In 2024, incidence increased from 28.67% in the 28th SMW to 48.23% in the 30th SMW and declined to zero by the 36th SMW. Peak weevil abundance was 0.89 per plant in both seasons. Peak grasshopper and aphid abundances were 0.56 per metre of row and 0.56 per leaf, respectively. Coccinellids reached 0.44 per plant in both seasons, while spiders peaked at 1.00 per plant in 2023 and 0.69 per plant in 2024. Exploratory same-week correlations between dead-heart incidence and minimum temperature differed in direction between seasons (r = 0.722 in 2023 and r = -0.744 in 2024). Because the data came from a single field plot with serial weekly assessments, these coefficients were interpreted descriptively rather than as confirmatory tests. The observations indicate that shoot-fly injury was concentrated during the early crop period, whereas secondary pests and natural enemies occurred at comparatively low densities. Multi-location studies with independent plot replication are required before weather-based prediction or economic-loss thresholds can be developed for browntop millet.

Field Evaluation of Different Insecticides against Shoot Fly [Atherigona approximata (Diptera: Muscidae)] in Browntop Millet

Krishana, Prabhu C. Ganiger, S. Amruth, Bairasandra Ashwathanarayana Hemanth — Sat, 25 Jul 2026 00:00:00 +0000

Shoot fly is an important seedling pest of millets, but crop-specific evidence for browntop millet remains limited. A two-season field experiment was conducted during the 2023 and 2024 kharif seasons at the Zonal Agricultural Research Station, University of Agricultural Sciences, GKVK, Bengaluru, India, to evaluate nine insecticidal treatments and an untreated control in browntop millet cultivar GPUBT-1. The experiment was arranged in a randomised complete block design with three replications. Three treatments were applied to the seed before sowing and six were applied as foliar sprays seven days after germination. Dead-heart incidence was recorded one day before foliar application and at 3, 5, and 10 days after application. Among the seed treatments, thiamethoxam 30 FS at 10 ml kg-1 seed produced the lowest descriptive seasonal mean dead-heart incidence in both years (14.45% in 2023 and 15.56% in 2024), corresponding to reductions of 50.00% and 55.56%, respectively, relative to the untreated control. Cyantraniliprole 19.8% + thiamethoxam 19.8% FS was the next most consistent seed treatment. Among the foliar treatments, lambda-cyhalothrin 5% EC at 1 ml L-1 produced the lowest incidence at 10 days after application (10.00% in 2023 and 11.11% in 2024). The highest recorded grain yield and descriptive benefit-cost ratio were obtained with thiamethoxam 30 FS seed treatment (805.56 kg ha-1 and 4.39, respectively), followed by lambda-cyhalothrin 5% EC (736.11 kg ha-1 and 3.90). The findings identify thiamethoxam seed treatment and lambda-cyhalothrin foliar application as promising options within their respective application categories. Multi-location validation and compliance with current crop-specific pesticide labels are required before broad operational recommendations.