Annual Research & Review in Biology

Aim: In recent years, natural products from medicinal plants have received considerable attention. Thymoquinone, the major compound from Nigella sativa L.  Is the most used due to its several pharmacological properties. This study was undertaken to evaluate the antioxidant effect of thymoquinone which is very useful in controlling free radicals noxious species causing the induction and / or amplification of a number of pathologies.

Study Design: Spectrophotometric methods.

Place and Duration of Study: Biochemistry Department, Applied Biochemistry Laboratory, Nature and Life Sciences Faculty, Ferhat Abbas Setif 1 University, Setif, Algeria, between December 2016 and September 2017.

Methodology: In vitro antioxidant study was characterized by using free radicals scavenging methods with reducing power, lipid peroxidation and ß-carotene bleaching assays. All tests were realized by spectrophotometric methods.

Results: Our study showed that thymoquinone is a potent antioxidant. It is less effective as a scavenger of both DPPH and ABTS radicals with IC₅₀ of 125.65 ± 0.76 and 332.5 ± 14.39 µg/ml, respectively; While it is  a strong  scavenger of hydroxyl radical with IC₅₀ of 26.3 ± 0.59 µg/ml and very strong hydrogen peroxide  scavenger  with IC₅₀ of 11.0  ± 0.57 µg/ml.  As superoxide anion scavenger it has inhibition ability less than 50%. In lipid peroxidation, TQ had a very efficient activity it inhibits peroxidation of β- carotene by 73.58 ± 0.50%. Thus, in lipid peroxidation assay, TQ had also a significant activity with percent inhibition of 79.5 ± 2.12%. 

Conclusion: Our results revealed that thymoquinone possesses a low antioxidant activity against DPPH, ABTS and superoxide anion radicals. Thus, it has a very low reducing power capacity, whereas it is a strong hydrogen peroxide, hydroxyl scavenger and lipid peroxidation inhibitor.

Among the various microorganisms reported for their capabilities of cellulases and xylanases production, fungi are the most potent producers. This study reports the production of xylanolytic and cellulolytic enzymes by potential decomposing fungal isolates using a cheap medium containing green manure substrate and chemically defined basal medium under solid-state culture. A number of decomposing fungi were screened for cellulolytic and xylanolytic potential. The  enzyme  production  with  purified  carboxy  methyl  cellulose  (CMC)  and  birch  wood  xylan  was  studied and found to be promising. Aspergillus niger produced the highest amount of endoglucanase and xylanase viz., 3.635 U mg^-1 protein min^-1 and 2498.20 U mg^-1 protein min^-1, respectively at 25ºC. Growth and enzyme production was affected by the alterations in temperature. Highest production of endoglucanse and xylanase were noted at 25ºC and 30ºC.

Objectives: Youngia japonica (YJA), belonging to the family asteraceae, exhibits strong antiallergic, antioxidant and antitumor activities. The present study was carried out to assess the antioxidant potentials, analgesic, anti-inflammatory and CNS depressant activities of different fractions of YJA plant extracts.

Study Design: For the purpose of this experiment the different plant extracts were subjected for an in-vitro and in-vivo study.

Place and Duration of Study: The study was carried out on March 2015 in the Department of Pharmacy, Southeast University, Dhaka, Bangladesh.

Methods: The antioxidant capacity of ethyl acetate (EA), pet ether (PET) and chloroform(CLF) extracts of YJA  were investigated for free radical scavenging activity using DPPH and hydroxyl radical scavenging assay. Total antioxidant activity and total phenolic content of different extracts were determined spectroscopically. Analgesic activity was evaluated by using acetic acid induced writhing, formalin test and eddy’s hot plate method. Extracts of YJA were also investigated for anti-inflammatory activity using carrageenan induced hind paw edema model. The CNS depressant activity was evaluated by hole cross test.

Results: In DPPH scavenging assay, CLF exhibited the highest DPPH scavenging activity (IC₅₀ 9.70 μg/ml). In case of hydroxyl radical scavenging assay, EA extracts showed the most significant activity (IC₅₀ 15.09 µg/ml). This result was in line up with the total phenolic content where EA extracts possessed the highest amount of it (43.92 mg of GAE / gm. of dried extract). Moreover, the highest total antioxidant activity was also found in EA fraction (109.30 GAE/gm of dried sample) that rationalizes the previous outcome. All fractions significantly (p<0.01) reduced the writhing and the number of licking in a dose dependent manner (100 and 200 mg/kg). The Extracts also showed significant (p<0.001) inhibition of carrageenan induced paw edema. A statistically significant (p<0.001) decrease in locomotor activity was also observed.

Conclusion: The result demonstrates that the YJA has appreciable antioxidant, analgesic, anti-inflammatory and CNS depressant activities.

Microflora (Cyanobacteria, Algae and Fungi) associated with the freshwater leech namely, Limnatis niloticawere observed for this particular study. The number of catch leeches was higher at Saiysad fresh water bodies (5-28 taxa) than that of Gahdeer Albannat water (1 taxon) throughout the wet season. The Saiysad water contains low oxygen and is highly polluted in comparison to other water bodies. The green algae and diatoms constitute the main bulk of the phytoplankton population of the following two water bodies. Though cyanobacteria in this particular water body of Saiyasad fresh water are much higher in respect to the others, so as the number of leeches are also higherin it respectively. Twenty-one fungal species those are representing 10 genera were collected from the Leech samples (jaws, pharynx and intestine) on the culture media of Potato Dextrose Agar.  After th isolation of fungus were done from its carried devices Then also the phytoplanktons show a rapid growth in the respective medium.

Pollution from petroleum products is of public health concern because of its attendant health and environmental impacts.

Aims: To study the biodegradation of Bonny light crude petroleum by bacteria isolated from soils of three different automobile mechanic workshops in Ota, Ogun State.

Study Design: Contaminated soils from three (3) different auto-mechanic sources were enriched with Bonny light crude oil for a period of twenty-one (21) days after which the culture was changed and further enriched using crude oil as the only source of carbon and energy.

Place and Duration of Study: Department of Biological Sciences (Microbiology Unit), Covenant University, Ota, Ogun State Nigeria, between June 2016 and March 2017.

Methodology: Bacteria were isolated using standard microbiological techniques from enrichment of the soil samples in minimal salt medium (MSM) supplemented with 1% (v/v) crude petroleum as the only source of carbon and energy. The petroleum utilizing bacteria belonging to the genera Bacillus sp. (SB4), Pseudomonas sp. (SC8), Serratia sp. (SC11), and Acinetobacter sp. (SC12) were screened and subjected to oil degradation procedures. Gas Chromatographic (GC) analysis was used to analyze the component and percentage of the petroleum utilized. Plasmid curing and profiling were performed to determine whether the ability to utilize carbon is plasmid or chromosomally encoded.

Results: Four (4) bacterial strains out of thirty-six (36) bacterial isolates were able to utilize petroleum as energy source. The GC fingerprints showed that both the aliphatic and aromatic components of crude petroleum were reduced to varying degree with the exception of nonadecane C19. Strain SC11 could not reduce anthracene, chrysene, benzo(a)pyrene and pyrene components of the crude petroleum. Strain SB4 depleted 24% - 57% of the aliphatic and 20% - 42% of the aromatics components while strain SC8 depleted 38% - 67% of the aliphatic and 30% - 79% of the aromatics components. However, strain SC11 only depleted 12% - 46% of the aliphatic and 13% - 29% of the aromatics components of the crude petroleum used.

Conclusion: All organisms harbored plasmid which suggests that petroleum degradation capabilities could be plasmid encoded. This indicates that the petroleum utilizing bacteria which are part of the ecosystem could be used for natural remediation of petroleum polluted environments.