Biotechnology Journal International

Aim: The aim of this work was to find new fungal sources of biosurfactants via bioprospecting and to produce biosurfactants from fungal isolates using inexpensive culture media.

Methodology:  Bioprocess tests were conducted with five fungal species isolated from soil from the Amazon region in order to investigate which of them presented the highest productivity in a kinetics experiment. The possibility of using the peels from the fruit of Astrocaryum aculeatum Meyer (PFAC), Bactris gasipaes Kunth (PFBG), Theobroma grandiflorum Schumann (PFTG), Musa paradisiaca (PFMP) as substrates was also evaluated.

Results: Fusarium oxysporum LM 5634 had the highest productivity, and PFBG was the best substrate for biosurfactant production.

Conclusion: Thus, the present study showed the potential of fungi and wastes (fruit peels) from the Amazon region for biosurfactant production.

Flavonoids have been shown to have antioxidant factors and effective against hepatotoxicity.  This in vivo study aimed to evaluate the efficacy of flavonoids rich extracts in a model of chemical-induced liver cell injury.

Materials and Methods: Flavonoids were extracted from leaves and flowers of Arbutus pavarii using Microwave assisted extraction method. Different concentrations of extracted flavonoids (200, 500, 1000, 2000 and 5000mg/kg bw) were evaluated up to two weeks on mice model. The hepatoprotective effects of the extracts were examined using mice pretreated orally with 200 and 400 mg/kg bw of flavonoids extracted from leaves and flowers as well as their combination (200 mg/kg; 1:1) for 28 days.  At day 28, the mice were received orally a single dose of 1ml/kg CCl₄ in corn oil. Forty-eight hours after Carbon tetrachloride (CCl₄₎ treatment, the animals were sacrificed and their liver and blood samples were collected for determination of biochemical parameters (Alkaline phosphatase (ALT), Aspartate-aminotransferase (AST) and Alanine-aminotransferase (ALP)), histopathological investigation and antioxidant status.  

Results: Treatment of the mice with a daily dose of flavonoids extracts up to 5 g/kg bw did not cause mortality and did not show hepatotoxicity. Pretreatment with extracts decreased the increased serum levels of ALT, AST, and ALP, decreased lipid peroxidation and maintained the levels of glutathione and antioxidant enzymes status in the CCl₄ treated mice, especially in the group treated with combined extracts. The hepato-protcitve effects were confirmed by histopathological examinations.

Conclusion: The results shown by the extracted flavonoids need further investigation.

Seedlessness is a major objective in Morocco Citrus improvement programmes. Triploidy has played an important role in the development of new seedless mandarin cultivars for fresh fruit market and has received increasing attention for the consumers. For that, many series of diploid crosses were assessed. At maturity, the fruits have been harvested, and small embryos were extracted from undeveloped seed and cultured on the medium of Murashig and Skoog supplemented with 1mg/l gibberellic acid according. Triploids seedling selected by flow cytometry analysis were budded on Troyer citrange and planted in INRA domain with spacing 6 m X 3 m. Tow new seedless selections of mandarins have been evaluated in a citrus breeding program at Morocco INRA: Hana and Aya that were compared with their female parent clementine Sidi Aissa. These promising seedless mandarins were identified by easy-peeling, juicy fruits, have a pleasant taste and are sweet like the Sidi Aissa Clementine. These clones, showing commercial interest, were described and registered in Moroccan official catalogue.

Aim: The study of laccase production by Trametes pubescens cultured on cladode extractive residues alone, and as co-carbon source with wheat, using submerged fermentation condition.

Place and Duration of Study: Biotechnology Laboratory, Durban University of Technology, Durban, South Africa.

Methodology: Plant extraction, submerged fermentation, enzyme activity and characterization techniques were utilized.

Results: The highest laccase activity was observed at 60-80% wheat: residue ratio combinations under submerged conditions with copper and xylidine supplementation. Partially purified enzyme fractions showed similar characteristics at different temperatures and pHs. There was good retention of relative enzyme activity at temperatures near 60°C, and pH stability from pH 4.0-6.0. At optimal culture conditions laccase activity was highest at 49.01±0.21 U/ml (80% wheat: 20% residue ratio), and lower at 10.02±0.51 U/ml (80% wheat:20% NEP residue). The optimum temperature for laccase fractions was 25°C and pH optimum at 5. Highest specific activity was 3.55 U/mg of protein for the 80% wheat: 20% residue ratio laccase extract.

Conclusion: These results show the potential of cladode extractable phenol residues as potential economic growth medium for laccase production, offering a new alternative use for this agro-industrial and/or laboratory by-product.

Gas Chromatography-Mass Spectrometric (GC-MS) was used to investigate the chemical constituents of the essential oil from fresh leaves of Nicotiana tabacum L. The result revealed thirty six (36) compounds representing 100% of the essential oil characterized from the leaves of Nicotiana tabacum L. The major constituents are 3, 7, 11, 15-Tetramethyl-2-hexadecen-1-ol 16.37%, P-xylene 12.37%, Cyclohexane 8.43%, Farnesol isomer a 3.08%, and 1-Naphthalenepropanol 3.08%.