Asian Journal of Biotechnology - Current Issue

Biological Control of Foodborne Pathogenic Enterobacter sp. and Bacillus sp. Using Different Spice Extracts Available in Bangladesh

10 June, 2026

Background and Objective: The relatively inexpensive, widely available poultry meat and eggs can be of centralimportance to meet shortfalls in essential nutrients, particularly to impoverished people. Contamination of foods by pathogenic microbes causes consumer illness. In this study, antibacterial activity of spice extracts against isolated foodborne pathogenic bacterial strains were evaluated. Materials and Methods: Egg and meat samples were collected from poultry egg and meat retailers of local market and screened on MacConkey and Mannitol salt agar media, respectively. The isolates were identified by morphological, biochemical and 16S rRNA gene sequence analysis. Anti-bacterial activity of different spice extracts against isolated bacteria was tested through disc diffusion method. Cytotoxicity was evaluated through probit mortality analysis software. Results: Bacillus sp. (from meat) showed more toxicity (LC₅₀ = 95.6205 μL mL^–¹) than Enterobacter sp. (from egg) (LC₅₀ = 143.2504 μL mL^–¹) against Artemia salina. For biological control, methanolic and aqueous extracts of Cinnamomum verum, Syzygium aromaticum, Piper chaba, Zingiber officinale were used. Methanolic extract of S. aromaticum acted as potential antimicrobial agent against Bacillus sp. with a inhibition zones of 15±0, 18.33±0.58 and 21±0 mm at a concentration of 50, 75, 100 μg mL^–¹, respectively. Similarly, Enterobacter sp. was susceptible at the same doses with a inhibition zones of 15.33±0.58, 16.67±0.58 and 18±0 mm. Moreover, C. verum oil with a dose of 30 μL showed the highest growth inhibitory effect against Bacillus sp. (inhibition zone 40±1 mm) than Enterobacter sp. (inhibition zone 34.33±1.53 mm). Conclusion: The result suggests that spices represent an alternative source of natural antibacterial substances for inhibiting the growth of foodborne bacteria.

Infusion Extraction of Toxin from Chili Pepper (Capsicum baccatum) for Bedbug Protection

10 June, 2026

Background and Objective: The developing trend of resistance in bed bugs toward synthetic insecticidal agents makes their management extremely difficult. So, there is an urgent need to develop new approach in the protection of bedbugs consist of using native plants with insecticidal value. The present experiment was conducted to protect bed bugs through the use of Capsicum baccatum (chilli pepper) extract. Materials and Methods: The experiment was conducted to extract toxin from Capsicum baccatum for bedbug protection. The extract was prepared in 3 different concentrations in liquid form viz. 14.2, 16 and 18.8% as a direct admixture of salt. Adult bedbugs were collected from student’s dormitory The collected insects were allowed to mate for 3 days and eggs from ovipositor site were collected. The extract was sprayed on adult bedbugs designed in experimental block with 3 treatment groups. The efficiency of acute toxicity of the extract was checked on the percentage of adults mortality in control with percentage control and inhibition of adult emergence was checked by percentage of adult emergence inhibition in control [IE %]. Bonferroni correction test was used to adjust for multiple comparisons of the blocks at 95% confidence interval [CI]. The experimental design for mortality and emergence test was randomized block design. Results: The result revealed that the extract was 100% effective at killing bedbugs and inhibiting adult emergence in all levels of concentration [CL] compared to treatments under control with significant mean difference (p<0.05). Conclusion: Generally, the study confirmed that the extract pose talented potential in protecting bedbugs and adult emergence inhibition only in small scale applications based on the demonstrated efficacy and reduced risk potential on non-target organisms and ecology.

Identification of Bioactive Peptides in Mussel Species of Kanyakumari Coast

10 June, 2026

Background and Objective: Anti-bacterial activity was evaluated in the whole body crude extracts of the 3 edible marine bivalves, namely Perna perna (brown mussel), Perna viridis (green mussel) and the parrot mussel collected from the coastal villages of Kanyakumari district. Materials and Methods: Six different solvents, namely ethanol, methanol, acetone, ethyl acetate, hexane and butanol were used to prepare the extracts. The efficacies of the whole body extract of different solvents were assessed for the antimicrobial activity against 13 different pathogenic bacteria viz., Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Proteus vulgaris, Staphylococcus epidermis, Klebsiella pneumoniae, Bacillus subtilis, Salmonella paratyphi, Streptococcus pyogenes, Vibrio sp., Shigella sp. and Haemophilus influenza. Results: Of the 6 different solvents methanol exhibits the highest activity followed by ethanol and acetone. The methanolic extracts of P. viridis exhibit the highest activity against E. coli, S. typhi and P. aeruginosa. The ethanolic extract of P. viridis shows the highest activity against E. coli, P. aeruginosa, S. typhi, K. pneumoniae and acetone extract showed good activity against E. coli. The methanolic extracts of P. perna exhibit the highest activity against E. coli, S. aureus, S. typhi, P. vulgaris. The ethanolic extract of P. perna is active against P. vulgaris and B. subtilis and the ethanolic extract showed good activity against P. aeruginosa and Shigella species. The methanolic extracts of the parrot mussel exhibit the highest activity against E. coli and Streptococcus pyogenes, ethanol extract shows good activity against E. coli and Staphylococcus aureus and the acetone extract shows maximum antibacterial activity against P. aeruginosa. Conclusion: The findings of the present study confirm that the mussel species have antimicrobial activity and that this activity appears to be dependent on the solvent used for the extraction process. FTIR analysis reveals the presence of bioactive compounds signals at different ranges.

Effect of Balanites aegyptiaca Fruit-pericarp Extract on Fructose Induced Hyperglycemia and Hyperlipidemia in Rats

10 June, 2026

Background and Objective: High fructose intake has been reported to alter metabolisms leading to hyperglycemia and dyslipidemia. This study investigated the effect of Balanites aegyptiaca fruit-pericarp extract on high fructose fed rats. Materials and Methods: Balanites aegyptiaca fruits after collection were dehulled to obtain pericarps, air-dried and pulverized into powdered then extracted with ethanol. Phytochemical content and acute toxicity of the extract were ascertained. The study was conducted on rats divided into 7 groups of 5 each, namely; normal control, extract control (received 600 mg kg^–¹ b.wt., extract), fructose control (received 30% fructose solution), standard drug control (fructose fed rats treated with simvastatin 25 mg kg^–¹) while group 4-6 were fructose fed rats treated with extract at 200, 400 and 800 mg kg^–¹ b.wt.. After 21 days of extract administration, rats were sacrificed, blood collected and serum separated which was used for the biochemical analysis. Results: The study showed pericarp extract possess variety of phytochemical (phenols, flavonoids, saponins, tannins) and is safe with lethal median dose (LD₅₀) assumed at 4000 mg kg^–¹ b.wt., of rats. Lipid profile varies significantly (p<0.05) between rats fed fructose untreated and treated whereas, fasting blood glucose and insulin are insignificantly (p>0.05) different among all groups. Fructose untreated rats had the highest weight increase at 17% compare to the treated rats. Conclusion: The study found pericarp extract of Balanites aegyptiaca safe, possess important phytochemicals and able to prevent fructose induced hyperglycemia and hyperlipidemia in rats. It may be a good source for the management of metabolic disorders.

Physiological Responses of Moringa (Moringa stenopetala L.) Seedlings to Drought Stress under Greenhouse Conditions, Southern Ethiopia

10 June, 2026

Background and Objective: Moringa stenopetala L. is a plant called miracle plant due to its adaptability and versatility in use. However, in spite of its marvelous importance, the plant has got little attention for research based on stress physiology. Therefore, in this study, pot experiment was conducted to investigate the chlorophylls concentration, Leaf gas exchanges, stomata traits and leaf water status responses of Moringa stenopetala L. accessions seedlings to drought stress under greenhouse condition. Materials and Methods: The experiment was consisted of 3 accessions (Konso, Arba Minch Zuria and Humbo) and 4 drought stresses (daily, 5 days interval, 10 days interval and 15 days interval watering) assigned in completely randomized design with 3 replications. Results: The accession “Arbaminch Zuria” was higher in all parameters except stomata number. Regarding to water stress, the experiment shown that, increased water stress reduced all parameters except stomata number. Additionally, photosynthetic rate, transpiration rate, stomatal conductance and leaf relative water content were significantly influenced due to the interaction effect of accession and drought stress. Accession “Arbaminch Zuria” grown under daily watering was higher in all traits those indicated significant due to interaction. Conclusion: Therefore, Arbaminch Zuria can be taken as a better accession both under stressed and unstressed conditions for production of moringa seedling. Furthermore, study is still needed on more indigenous and exotic accession under different drought stress for longer periods of time as a perennial crop.

Fractionated Ethanol Extract of Balanites aegyptiaca Fruit-Mesocarp Effect on Diabetes Mellitus Model Rats

10 June, 2026

Background and Objective: Balanites aegyptiaca fruit is a useful source of hypoglycaemic remedy for management of diabetes in some part of Northern Nigeria. This study evaluated the effects of fractionated ethanol extracts of Balanites aegyptiaca fruit-mesocarp (BAFM) in streptozotocin-induced diabetic rats. Materials and Methods: Ethanol crude extract of BAFM was fractionated with water and ethyl acetate (1:1 v/v) then separated to obtain the specific extract-fraction. The extract-fractions were evaluated for antidiabetic activities in rats induced with diabetes. Diabetes mellitus was induced in male Wistar rats by intra-peritoneal injection of streptozotocin at a dose of 60 mg kg^–¹ body weight. Results: From the results, rats induced with diabetes were characterized by low serum insulin, hyperglycemia and decrease in body weights. Treatment with the extract-fractions of BAFM elevated serum insulin, lowered fasting blood glucose levels and reversed serum total cholesterol, triglyceride, low density lipoprotein cholesterol and very low density lipoprotein cholesterol levels, serum albumin and total protein. The aqueous fraction (AFF) was more comparable in lowering fasting blood glucose by 18.61% when compared to 24.62% by metformin. A significant increase in serum insulin levels was recorded in diabetic rats treated with AFF when compared to diabetic control rats and diabetic rats treated with ethyl acetate fraction. Conclusion: Both aqueous and ethyl acetate extract-fractions of BAFM exert hypoglycaemic, antihyperglycaemic and antilipidaemic effects. However, the aqueous fraction was more potent. This study is a step towards the isolation of bioactive components. Further research is needed to explore the bioactive component(s) responsible for the antidiabetic effects.

Carcass and Meat Differentiation of Burnt and Stripped Sheeps in Benin

10 June, 2026

Background and Objective: Post-mortem treatments, the cooling regime and the cutting method have a great influence on organoleptic quality of the meat such as the color and tenderness. The aim of this study was to evaluate meat quality of burnt sheep and stripped sheep in Benin. Material and Methods: Sixty samples of Longissimus dorsi, 30 burnt and 30 stripped Sahelian ewes in Cotonou slaughterhouse were used. Animals were all aged from 2-3 years and they were weighed before and after slaughter. Meat color, pH during 48 h post-mortem, loss of juice by cooking and tenderness were also measured. A sensory analysis (flavor, juiciness, tenderness and overall rating) of the boiled samples was carried out on small identical cubes of the meat. Results: The slaughtering lively weight and the hot carcass weight didn't vary from a type of dressing to another. Longissimus dorsi of burnt ewes has a lower red index, flavor and shear force than that of stripped (p<0.05). On the other hand, the initial and final pH and tenderness were higher in these same burnt. The juiciness and the water retention capacity didn’t vary from burnt to stripped ewes. Conclusion: The study on the carcass quality and technological and organoleptic quality of the ewes slaughtered at the Cotonou slaughterhouse showed the effect of the type of dressing on the quality of the meat. The burning technique seems to influence the yield of the hot carcass.

Analysis of Yardlong Bean (Vigna unguiculata Subsp. sesquipedalis) Genetic Diversity using RAPD Markers

10 June, 2026

Background and Objective: Yardlong bean is a well-known vegetable because of its long, slender, succulent pods and its protein content. In the present study genetic variation and relationships among yardlong bean genotypes were investigated thorough RAPD marker technique. Materials and Methods: Thirty six genotypes of yardlong bean were planted in the field to characterize their genetic relatedness and identify variation at molecular level. Sixteen decamer RAPD oligonucleotide primers were screened and out of these, 10 primers were chosen for further evaluation. Results: Altogether 94 RAPD bands were scored of which 82 were polymorphic. The amplified product size ranged from 150-900 bp. The primer OPB-08 amplified maximum number of polymorphic bands. The average number of polymorphic bands/primer was 8.2. The frequency of polymorphism ranged from 0.0278-0.9722. Nei’s pair-wise genetic distance ranged from 0.055-0.83. A UPGMA dendrogram of genetic similarity was constructed based on 82 polymorphic bands obtained from 10 primers. The UPGMA dendrogram divided the studied individuals into four main clusters. BD-1528 and BD-1524 accession formed distinct cluster (I and II, respectively). Most of the genotypes were observed in cluster IV (29 genotypes) which was further sub-divided into two sub-clusters which were subdivided into sub-sub-clusters making the genotypes diverse. Accessions collected from Bangladesh Agricultural Research Institute, showed significant diversification as they were widely distributed in 4 clusters. Conclusion: The variability among the genotypes has the potential to be used in future plant breeding program as well as for commercial production.

Microbial Degradation of the Organophosphorus Insecticide, Methyl Parathion Using the Natural Bacterial Isolate, Pseudomonas aeruginosa

10 June, 2026

Background and Objective: Pesticides are hazardous to human beings, flora, fauna and ecosystems. Though they are applied to increase the productivity in crop fields for controlling pests, they cause pollution in air, water and soil. Bioremediation is employed to clean polluted sites using organisms. Microbes are ubiquitous and some of them can degrade pesticides. Hence the present study has been designed to isolate a bacterial strain capable of degrading methyl parathion and to test its efficiency of degradation. Materials and Methods: Soil samples collected from contaminated crop fields were subjected to serial dilution, plating and incubation. From the grown colonies one colony was chosen and it was identified using biochemical tests. It was tested for its efficiency after exposing to 50, 100, 150 and 200 ppm for 30 h by monitoring changes in pH, orthophosphate, turbidity and the influence of sugars and immobilization. UV-visible spectrophotometry, HPLC analysis and statistical analysis were carried out to confirm the degradation efficiency of the natural isolate. Results: The natural isolate was identified as Pseudomonas aeruginosa based on the results of biochemical tests. Maximum orthophosphate was released in 200 ppm methyl parathion. The pH declined during degradation while turbidity exhibited an increase which indirectly indicated the degradation by the natural isolate. Orthophosphate level increased steadily when immobilized cells were tested. All the tested carbohydrates enhanced the release of orthophosphate. Both UV-visible spectrophotometry and HPLC analysis confirmed the degradation of the pesticide by the natural isolate. Conclusion: The natural isolate can be used to degrade pesticides like methyl parathion and its capacity can be enhanced by immobilization or supplementation with carbohydrates.