Asian Journal of Biology

Determination of Antibacterial Effect of Citrus aurantifolia on Respiratory Pathogenic Organisms and the Bioactive Supplements Responsible for the Effect

M. O. Emolade — 2026-05-22

The activity of any agent against microorganisms is as a result of the presence of substances That are capable of inhibiting the growth of the microorganism and These substances are referred to as bioactive agents, such as flavonoid, tannin, saponin and Alkaloid. It is observed that the potency of lime fruit is enhanced by the type of solvent used Indicating that there are some active ingredients in lime which have high antimicrobial effect but which would not be released except when lime fruit is used in conjunction with a particular solve morphological and biochemical characteristics of the isolates from the sputum samples. These isolates were identified to be Staphylococcus aureus, Streptococci spp., Klebsiella pneumoniae. The diameter of the zone of inhibition of the lime extract on the different Isolates. The antibacterial effect was compared based on the different solvents used which are Ethanol, methanol and chloroform and gentamicin antibiotic was used as a control. Staphylococcus aureus shows the highest inhibition zone on the three solvents followed by Streptococci spp. The minimum inhibitory concentration (MIC) and minimum bactericidal Concentration (MBC) of the lime extracts against the isolates. The most effective inhibition Was observed in 3.125mg/ml of chloroformic extract against Staphylococcus aureus and Streptococcus specie with an MBC value of 6.25mg/ml and 3.125mg/ml respectively. The least concentration was observed in chloroformic extract against Klebsiella pneumonia. The result of the phytochemical screening of Citrus aurantifolia, it was Observed to contain the following compounds; tannin, saponin, alkaloid and flavonoid.

Residual Effect of Laying Hen Manure on the Growth and Yield of Pearl Millet in the Sudano-Sahelian Zone of Burkina Faso

Sory Aboubacar — 2026-05-29

Background: Pearl millet is a key staple crop in Burkina Faso, vital for food security and livestock feed, but its productivity is limited by declining soil fertility and low use of expensive mineral fertilizers. Poultry manure, rich in nitrogen, phosphorus, and potassium, is emerging as a sustainable organic alternative to improve soil fertility and boost millet yields.

Aims: The present study aims to evaluate the residual effect of laying hen manure (LHM) on the growth, development, and yield of pearl millet, in order to better understand its role in promoting sustainable production systems.

Study Design: A field experiment was conducted using a Fisher’s randomized block design, consisting of five (05) treatments, each replicated three (03) times.

Place and Duration of Study: The experiment was carried out at the experimental station of the Rural Development Institute in Gampela, Burkina Faso during the rainy season of the 2022/2023 (June to November 2023) cropping year.

Methodology: The study evaluated the residual effects of previously applied fertilizers during the 2021/2022 season. In 2022/2023, no fertilizer was applied. Treatments included T0 (control), T1 (100 kg ha⁻¹ NPK + 50 kg ha⁻¹ urea), T2 (2.5 t ha⁻¹ LHM), T3 (5 t ha⁻¹ LHM), and T4 (7.5 t ha⁻¹ LHM). Growth parameters, yield components, and yields were measured and analyzed.

Results: The results showed that the residual effects of LHM significantly enhanced plant height, collar diameter, tiller number, fertile tillers, panicle length and diameter, as well as grain and straw yields. In contrast, the residual effect of mineral fertilization (NPK + urea) did not significantly influence these parameters. Among the treatments, LHM at 5 and 7.5 t ha⁻¹ produced the highest grain yields, reaching 3290.71 and 3528.63 kg ha⁻¹, respectively.

Conclusion: These findings suggest that the strategic use of LHM, even at alternating intervals, represents an effective approach to optimizing pearl millet yield while improving soil fertility in low-input agricultural systems. In particular, laying hen manure applied at 5 t ha^-1 could serve as a sustainable soil fertility management strategy for enhancing pearl millet productivity while supporting long-term soil health in the Sudano-Sahelian zone.

Developmental and Physiological Evaluation of Digloti (Litsea salicifolia) as a Potential Host Plant of Muga Silkworm (Antheraea assamensis): A Pioneer Study

Suraksha Chanotra — 2026-06-01

The Muga silkworm, Antheraea assamensis, is extensively recognised for its production of the distinctive golden Muga silk. Nevertheless, its reliance on a limited range of host plants, primarily Persea bombycina (Som) and Litsea monopetala (Soalu), presents significant concerns regarding the long-term sustainability of Muga sericulture under evolving climatic and ecological conditions. The present study provides the first comprehensive assessment of Digloti, Litsea salicifolia, as a prospective alternative host plant within Muga sericulture systems. Physiological analyses of L. salicifolia revealed high nitrogen content (2.4%), total chlorophyll (1.9 mg/g), and moisture content (70.1%), indicating favourable nutritional quality for larval development. The rearing performance of A. assamensis larvae on Digloti was assessed in terms of larval growth rate, instar duration, cocoon weight, shell ratio, and silk filament length. Results showed a survival rate of 89.6%, average cocoon weight of 5.1 g, shell ratio of 12.3%, and filament length of 510 m; comparable to those obtained with traditional hosts. The seasonal stability of leaf quality, together with the plant’s adaptability to diverse ecological conditions, further highlights its potential suitability. Consequently, Litsea salicifolia demonstrates considerable promise as a sustainable supplementary host plant capable of reducing pressure on existing resources while strengthening the resilience of Muga sericulture systems. Future investigations should focus on field-level validation, the optimisation of propagation techniques, and the integration of this species into agroforestry systems to support its large-scale adoption and utilisation.

The Role of Rhamnolipid-based Nanostructures in the Special Cleaning of Chemical Toxic Agents

Ramil Akhundov — 2026-06-03

Background: Persistent hydrophobic chemical toxic agents can strongly adhere to contaminated surfaces, making their removal difficult by conventional decontamination methods. Rhamnolipid-based nanostructures have emerged as promising environmentally friendly systems due to their adaptive interfacial properties and potential for enhanced toxin removal.

Aims: This study aims to systematically explain the role of rhamnolipid-based nanostructures in the decontamination process.

Study Design: The main idea is that the behavior of these systems is not constant and changes as the environmental conditions change. In particular, it was considered how changes in pH and ionic strength affect the shape of the nanostructures and how this affects the removal of chemical toxins from the surface. In this regard, the decontamination process is explained not only as surface cleaning, but also in conjunction with the change occurring at the structural level. The study is conceptual in nature and for this purpose a mechanistic model was built.

Methodology: The model shows the relationship between the transition between micelle and vesicle structures, surface tension, interaction between the surface and the toxin, and the desorption process.

Results: The results show that it is possible to influence the phase state of nanostructures by changing the environmental conditions. The increase in vesicle structures leads to a decrease in surface tension, a weakening of the bond between the surface and the toxin, and, as a result, an easier separation of the toxin from the surface.

Conclusion: At the same time, the effectiveness of this process depends on both the properties of the toxin and the structure of the surface. In general, this approach allows us to consider rhamnolipid systems not only as cleaners, but also as systems that can adapt to the environment and be controlled to some extent.

Growth and Exploitation Parameters of Pseudotolithus elongatus (Bowdich, 1825) from the Ebrié Lagoon, Côte d'Ivoire

KONÉ Tiéhoua — 2026-06-06

The geographical proximity of Ebrié Lagoon to densely populated areas such as the peri-urban zone of Abidjan leads to considerable exploitation of its resources. The present study aims to assess the exploitation and growth parameters of Pseudotolithus elongatus from the Ebrié Lagoon. This study was conducted from July 2013 to June 2015 on 512 specimens that were weighed in grams and measured in centimetres individually. Growth parameters were estimated using length–weight and length–frequency data. The growth and exploitation parameters estimated using the Von Bertalanffy equation and the FISAT II program indicate an asymptotic length L∞ = 66.15 cm and growth rate K = 0.14 year^-1. The estimated total mortality is Z = 0.63 year^-1; natural mortality (M) and fishing mortality (F) are respectively 0.40 year^-1 and 0.23 year^-1. The exploitation level E = 0.37 < 0.5 shows that Pseudotolithus elongatus is in a state of under-exploitation in the Ebrié lagoon. The analysis of the length–weight relationship revealed that Pseudotolithus elongatus exhibits positive allometric growth, indicating that weight increases faster than length. Estimates of key population parameters, including natural mortality, fishing mortality, and exploitation rate, suggest that the species is currently under-exploited in the Ebrié Lagoon. These findings indicate that the existing level of fishing pressure remains below critical thresholds and does not pose an immediate threat to stock sustainability. Consequently, the study concludes that the exploitation of P. elongatus could be moderately increased without compromising the long-term viability of the population, provided that appropriate management and monitoring measures are maintained.

Interactive Effects of Sowing Date and Planting Density on Productivity in Maize–groundnut Intercropping Systems

Anique Ahou Gbotto — 2026-06-11

Groundnut (Arachis hypogaea L.) and maize (Zea mays L.) are staple crops of major nutritional and economic importance in regions reliant on sustainable agriculture. This study aimed to evaluate the effects of sowing date and planting density on the productivity of a maize–groundnut intercropping system in Mankono, central-western Côte d’Ivoire. The experiment was conducted from April to July 2022 using a randomized complete block design with three replicates. Treatments combined crop type, sowing date (J0, J5, J10, and J15), and planting density. Groundnut was established at 250,000 plants/ha (20 × 20 cm) and 111,111 plants/ha (30 × 30 cm), while maize density was maintained at 10,000 plants ha⁻¹ (1 × 1 m). Agronomic and yield data were collected from 30 plants per plot for each species. Groundnut yield ranged from 0.28 to 1 t/ha and was primarily associated with pod number (4–14), biomass (78–122), and pod mass. In maize, agronomic traits were strongly related to yield (r > 60%), which varied from 0 to 1.26 t/ha. Planting density significantly influenced groundnut performance, with the 30 × 30 cm spacing producing the highest values for most parameters. Sowing date also significantly affected both crops, as simultaneous sowing (J0) resulted in the highest yields, whereas delayed sowing (up to J15) reduced productivity. The interaction between planting density and sowing date further influenced system performance, with the combination of 30 × 30 cm spacing and simultaneous sowing producing the best yields for both crops, while high-density planting combined with delayed sowing resulted in the lowest yields (≈0.4 t/ha). Overall, the results demonstrate that optimized spacing and simultaneous sowing enhance maize–groundnut intercropping productivity through improved resource-use complementarity, including more efficient use of light, water, nutrients, and growing space, while reducing interspecific competition.

Diversity and Distribution of Family Tettigoniidae (Orthoptera) from Low and Mid Hills of Himachal Pradesh, India

Kamal Saini — 2026-06-22

This study documents the diversity and distribution of Tettigoniidae (Orthoptera) in the low- and mid-hill regions of Himachal Pradesh, India. Field surveys were conducted from 2022 to 2025 across representative sites ranging from 300 to 2000 m asl. The surveyed habitats included agricultural fields, orchards, tea plantations, roadside bushlands, grasslands, riverine areas and forest-edge vegetation. Specimens were collected through hand-net sweeping, visual searching, beating of shrubs and small trees, and night-time acoustic surveys, followed by preservation and identification using diagnostic morphological characters and standard taxonomic keys. A total of 23 species belonging to 18 genera and seven subfamilies of Tettigoniidae were recorded from the study area. Phaneropterinae was the dominant subfamily, followed by Conocephalinae, while other subfamilies were represented by fewer species. The mid-hill region showed comparatively higher species richness than the low-hill region, and several species occurred in agro-forestry systems, grasslands, orchards and forest-edge habitats. Frequently encountered species included Ducetia japonica, Conocephalus maculatus, Mecopoda elongata and Letana megastridula. Diversity analysis indicated a Shannon index value of 2.486 and a Simpson index value of 0.9, suggesting appreciable diversity and relatively even distribution of species in the sampled areas. The findings indicate that low- and mid-hill habitats of Himachal Pradesh support a notable assemblage of katydids, including species associated with cultivated and semi-natural habitats under varying local management conditions. The study provides updated baseline information on the composition, habitat association and distribution of Tettigoniidae in these elevations and highlights the need for continued monitoring in landscapes undergoing horticultural and agricultural change.

New Records of Terrestrial Hemiptera Representing Fourteen Families from Betla National Park, Jharkhand, India

Pradip Chandra Saha — 2026-06-22

Terrestrial Hemiptera were surveyed in Betla National Park, Jharkhand, India, to document the diversity and distribution of true bugs within this protected area. Field collections were undertaken during 2021 across selected localities of the park, including Sidhapatch Watch Tower, Garhwa, Manika and Nanndaga, covering pre-monsoon and post-monsoon periods. Specimens were collected using light traps, sweep nets and hand-picking methods to represent taxa occurring in different habitats and microhabitats. The collected material was processed, identified following standard taxonomic procedures and deposited in the National Zoological Collections of the Zoological Survey of India, Kolkata. The study recorded 31 species of terrestrial Hemiptera belonging to 27 genera and 14 families under the suborders Auchenorrhyncha and Heteroptera. All recorded species are reported here as new distributional records for Betla National Park. Coreidae was the most species-rich family, with four species, whereas Cicadellidae, Aphrophoridae, Reduviidae, Rhopalidae and Rhyparochromidae were each represented by three species. Membracidae, Alydidae and Lygaeidae were represented by two species each, while Fulgoridae, Lophopidae, Geocoridae, Largidae and Pyrrhocoridae were represented by a single species each. The records include phytophagous and predatory taxa, indicating the presence of varied feeding guilds within the park. The highest number of species was recorded from the Sidhapatch Watch Tower area. By compiling locality-wise records and family-level representation, the present inventory provides the first consolidated account of terrestrial Hemiptera from Betla National Park. It also adds baseline distributional information for future faunistic, ecological and conservation-oriented studies in Jharkhand and for further documentation of insect diversity in protected forest ecosystems.

Cytotoxic Effects of Di-Ammonium Phosphate (DAP) Fertilizer on Allium cepa Root Tip Cells

Roushni Parween — 2026-06-08

The increasing use of Di-Ammonium Phosphate (DAP) fertilizer is mainly due to its high nitrogen and phosphorus content, which promotes plant growth and agricultural productivity. However, excessive and prolonged use of DAP may adversely affect soil fertility and induce cytotoxic effects in living organisms. Therefore, the present study was conducted to evaluate the cytotoxic effects of DAP on Allium cepa (onion) root tip cells. Three concentrations of DAP, namely 0.4 g/L, 0.8 g/L, and 2.0 g/L, were used for treatment, while untreated roots served as the control group. The root tip cells were exposed to the treatments for 96 hours. The mitotic index decreased from 15.21 ± 0.77 in the control group to 13.63 ± 1.38, 9.60 ± 0.70, and 4.80 ± 0.40 with increasing concentrations of DAP, indicating a concentration-dependent inhibition of cell division. The frequency of chromosomal abnormalities also increased with increasing DAP concentration. The most common abnormalities observed were multipolar spindle formation, laggard chromosomes, anaphase bridges, and polyploidy. The findings indicate that prolonged exposure to higher concentrations of DAP induces significant cytotoxic effects in Allium cepa root meristem cells and may interfere with normal mitotic activity and chromosomal behavior.