Journal of Bioprocessing & Biotechniques

Different Fusarium oxysporum isolates were tested under greenhouse conditions to determine their virulence potential toward tomato plants. Severity and development of Fusarium wilt disease was recorded 4, 6 and 8 weeks after pathogen inoculation. Chromatogram assay was conducted using HPLC to evaluate the capability of the tested isolates to produce Fusaric acid and to investigate the possible correlation between FA accumulation and Fusarium wilt disease development on tomato plants. The results showed that all tested isolates were pathogenic and varied significantly with regard to their virulence potential on tomato under the test conditions. The results showed also that all tested isolates were able to produce FA. Moreover, remarkable variation in FA accumulation was observed among the tested isolates at 4, 6 and 8 weeks post inoculation with the individual isolates. Four weeks post inoculation; the recorded data indicated that no clear correlation could be detected between FA accumulation and virulence of the tested isolates. In contrary, FA accumulation was in positive proportional relationship with virulence of the tested Fusarium isolates at 6 weeks post inoculation. Furthermore, differences in production of total secondary metabolites were observed within Fusarium isolates under in vitro conditions. These results revealed that FA could be play an important role in the development of Fusarium wilt disease at middle and last stages of tomato growth, while, it seems that no distinctive role of FA in the first stages of pathogenesis process of the tested Fusarium oxysporum isolates.

Rice straw, an agricultural waste, is readily available as a potential feedstock for the production of fermentable sugars. However, the recalcitrant nature of the lignin during digestion has been the major hindrances for the feasibility of the anaerobic process. At the same time, conversion of animal manure to value added product like biofuels is an important breakthrough for alternative treatment of such materials. Considering the aforementioned statements, in this study, we propose a combined use of alkaline and biological pretreatment of rice straw followed by the subsequent anaerobic co-digestion with pig manure for the production of methane. 1.5M NaOH was used for alkaline pretreatment which improved the delignification of the rice straw by removing 45.5% of the lignin content. Aspergillus niger BCRC31130 was employed for the biological pretreatment. Alkaline pretreatment followed by five days of biological pretreatment and subsequent thermophilic co-digestion resulted in the highest amount of methane and reducing sugars production 1834.20 mL and 2.23 g/L respectively. Methane production of the proposed process was 3.17 times higher than that obtained from the untreated rice straw. These results suggested that the enhancement of biodegradation of the rice straw through the combined use of alkaline and biological pretreatment led to higher production of reducing sugars which were converted to methane during co-digestion.

The plant growth enhancer property of seaweeds has been studied in different crops. Seaweed (Sargassum wightii and Uluva lectuca) were collected from costal region of Mangrol and studied for its effect on germination and storage of chickpea. Chickpea seeds were soaked in 1% seaweed extracts for 6 h and dried at room temperature before sowing for germination in the soil. Percentage of seeds germination was less in S. wightii (67%) and U. lectuca (65%) treated seeds as compared to control. Furthermore, the treatment also prolonged germination time as compared to untreated control. Seaweed extracts effects on seeds viability upon longer storage was affected by the storage conditions. For instance, storage of seeds treated with seaweeds extracts at room temperature was more affected as compared to 4-8°C and -20°C. These results showed that seaweed extract is possible to use for increasing post harvest shelf life of chickpea without affecting its natural texture.

Lignocellulosics are widely available natural products which are the tremendous source for the production of enzymes being used for the numerous applications in food, feed, paper, textile and agro-biotechnological industries, ethanol production, bioremediation processes and many more. Enzyme productions from microorganisms are stimulated aggressively through solid state fermentation which meets the demand of getting rid of agro-industrial waste and strengthen the consumption of renewable resources through biotechnology. Though well-developed techniques for enzyme production by submerged fermentation has been found very successful at the industrial sectors; solid state fermentation helps to overcome to the issues of production cost and high yield. Additionally the availability of the substrate with very much economical rate can compensate the overall economic expenses which promote the application of solid state fermentation at industrial level. However several reports regarding fermentation techniques and their pre-treatments are available, the present review will discuss about utilization of lignocellulosics through solid state fermentation for production of enzymes and their enhanced applications in different sectors in recent years.