Production, Properties And Applications Of Mycelium-Bound Lipase Of A Locally Isolated Strain Of Aspergillus Flavus Link

One of the most promising processes using lipase which will offer great potential application especially in term of cost reduction, is the use of mycelium-bound lipase (naturally immobilized lipase). However, there has been little work reported on the technology using mycelium-bound lipase (naturally immobilize) and work using it, is limited to a few microorganisms. This study was conducted with the aims to identifying a new source of mycelium-bound lipase, and consequently to study it's production, properties and applications.Aspergillus flavus, isolated from copra meal, produces a lipase (EC 3.1.1.3) which is partly bound to the mycelium. The production of the mycelium-bound lipase is concomitant with growth, and declines when growth ceases. Maximum productivity of the enzyme is obtained when the culture is incubated at 30°C, an initial culture pH of 6.5 and with 2% (w/v) each of com oil and yeast extract as carbon and organic nitrogen sources, respectively. Yeast extract affects not only the production of lipase but also the secretion of proteases into the culture medium. The presence of EDTA improved the productivity of the mycelium-bound lipase by 26% although growth of A. flavus was inhibited by 11%. The addition of Tween 80, into culture medium, decreased the activity of mycelium-bound lipase

Enrichment of Mung Bean with L-DOPA, GABA, Essential Amino Acids via Controlled Biofermentation Strategy

L-DOPA (L-3,4-dihydroxyphenylalanine) the precursor of neurotransmitter dopamine is used in the management of Parkinson disease and effective in controlling diabetic state. Gamma-aminobutyric acid (GABA), a non-protein amino acid is known to have many pharmacological functions and plays a major role in inhibiting neurotransmitter in brain. Whereas essential amino acids can't synthesize in human body and it must be taken from foods to maintain good immune function. This study aims to evaluate the enrichment of mung bean with L-DOPA, GABA and essential amino acids via controlled solid state fermentation using Rhizopus strain 5351. Fermentation was carried out for a duration up to 48 h at 30 °C and the samples were analyzed at certain time intervals. The concentration of glucosamine and beta-glucosidase, which indicated the growth of fungal was noted low at the early growth stage (0 to 10 h), but it was observing increased linearly within 18 to 48 h growth periods. The L-DOPA was produced after 10 h fermentation time (0.008 g/100 g dry weight, DW) and the highest yield of L-DOPA content (0.07 g/100 g DW) was attained at the fermentation time of 28 h. However, the concentration of L-DOPA was noted decreased after that. The protease activity, free and essential amino acids content also showed a drastic increment within the fermentation period of 10 to 38 h. The highest content of free and essential amino acids (FAAs and EAAs) and the protease activity of fermented mung bean were exhibited at 38 h incubation time, which were 3.74 g/100 g DW, 1.43 g/100 g DW and 18.4 U/g dry weight, respectively. The GABA content of fermented mung bean was found low (0.019 - 0.021 g/100 g DW) at early incubation time (0-10 h), however, it showed a drastic increment in the fermented mung bean after 18 h (0.132 g/100 g DW) and continuously increased until 38 h (0.198 g/100 g DW). This study showed the potential of solid state fermentation as a good strategy to enrich the fermented mung bean with L-DOPA, GABA and other beneficial bioactive compounds which play an important role to maintain good health as it helps to enhance our immune system and regulating neurotransmitter function

Composition and thermal characteristics of Madhuca longifolia seed fat and its solid and liquid fractions

This study was to characterize the seed fat from Madhuca longifolia known as Mee fat and its solid and liquid fractions with the objective of distinguishing them. A sample of Mee fat was partitioned into solid and liquid fractions using acetone as the solvent medium. The isolated fractions were compared to the native Mee fat sample with respect to various physico-chemical parameters using standard chemical methods as well as instrumental techniques such as, gas liquid chromatography (GLC), reversed-phase high performance liquid chromatography (RP-HPLC), and differential scanning calorimetry (DSC). Basic analyses indicated that there were wide variations between the native sample and its fractions with respect to iodine value (IV), and slip melting point (SMP). The cloud point (CP) of the liquid fraction was found to be 10.5 degrees C. Fatty acid compositional analyses showed that the proportion of saturated fatty acids (SFA) such as palmitic and stearic went up in the high-melting fraction (HMF) while in low-melting fraction (LMF) the proportion of unsaturated fatty acid (USFA) such as oleic and lenoleic increased. According to the HPLC analyses, Mee fat had a tiacyl glycerol (TAG) sequence similar to that of palm oil. After fractionation, the solid and liquid fractions obtained were found to have TAG profiles very much different from the native sample. Thermal analyses by DSC showed that Mee fat had two-widely separated high and low melting thermal transitions, a feature which was beneficial for the effective separation of solid and liquid fractions. The thermal profiles displayed by the fractions were clearly distinguishable from that of the native sample

Improvement of the specific activity of the extracted mycelium-bound lipase of Aspergillus flavus

Specific activity of lipase extracted from the mycelium of Aspergillus flavus, obtained from 3-day-old culture, increased nearly two times higher than from its culture supernatant. Different types of parameters were tested to optimise the extraction of mycelium-bound lipase. Highest specific activity of A. flavus lipase was obtained at 30 °C for 30 min with the agitation rate of 200 rev/min. Tris-HCl buffer (0.05 M) at pH 8.2 was the best extractant followed by Triton X-100 (0.1%), EDTA (0.01 M), NaCl (1 M) and Tween-80 (0.01%). The optimised conditions developed for the extraction of mycelium-bound lipase improved the purity of this lipase by 2.9 times higher than the control

Investment in technology based small and medium sized firms in Malaysia: roles for commercial banks

Financing is an important input in every business which allows for the smooth running of day-to-day operations, asset acquisitions, expert recruitment, and development of marketing and distribution channels. This is especially the case for high-tech startups that must undergo four development stages to turn ideas into commercial products and become full-blown enterprises; concept formation, amassing of resources, product development and business development. The purpose of this research is to understand the fundamental role of banks in Malaysia in bridging the startups financing gap, thereby, helping to grow technology based small and medium sized enterprises in the country. A qualitative research approach which aims first to identify all the commercial and investment banks in the country, then with a select sample size of ten biggest banks shall administer a semi-structured/open ended questionnaire. This methodology will allow respondents to open up on critical issues to be discussed and not limiting them to certain choices as in the case with a structured form of interview. Banks in Malaysia are not willing to finance high technology small and medium enterprises since it is a high risk industry. A the findings are compared to what is obtainable in other countries and Europe and America

Enhanced Virgin Coconut Oil (EVCO) as Natural Postmilking Teat Germicide to Control Environmental Mastitis Pathogens

The antimicrobial capability of oil containing medium-chain fatty acids and their corresponding monoglycerides, known as Enhanced Virgin Coconut Oil (EVCO) against microorganisms isolated from bovine mastitis milk was studied. EVCO contains an effective amount of medium-chain free fatty acids (caprylic, capric and lauric acid) and their corresponding derivatives (monocaprylin, monocaprin and monolaurin) can act as antimicrobial agent with broad spectrum of antimicrobial properties. An in vitro assessment of EVCO against bovine mastitis microorganisms isolated from locally collected mastitis milk samples was conducted to determine its minimum bactericidal concentration (MBC>99). In general, EVCO exhibited its great antimicrobial capability to kill all mastitis microorganisms isolated from the mastitis milk sample at different concentrations of MBC>99 value. In fact, EVCO was found more effective to kill Mycoplasma sp. and gram positive microbes rather than gram negative microbes, especially in Mycoplasma bovis, Acholeplasma oculi, Enterococcus sp., Streptococcus sp. and Staphylococcus aureus with lower MBC>99 values in comparison with the synthetic antibiotic, Mastivet. A further investigation of the antimicrobial activities of EVCO against Staphylococcus aureus and Mycoplasma bovis against time revealed that EVCO was more efficient in killing these two microorganisms in a shorter time at a lower concentration as opposed to Mastivet. These findings indicated that EVCO has great potential application in postmilking teat germicide, which can be used as a preventive measure to control mastitis cases, especially against environmental mastitis pathogens

Effect of chemical refining on the quality of kenaf (hibiscus cannabinus) seed oil

Crude kenaf seed oil was obtained by solvent extraction and chemically refined using industrial refining process, which includes degumming, neutralization, bleaching, and deodorization. The changes in physical characteristics, oxidation indexes, antioxidant activity, bioactive compounds, and fatty acid composition were determined after each stage of refining. The results obtained showed that there was no significant difference in the specific gravity of kenaf seed oil, but there was a significant increase in the refractive index and a significant decrease in the a* and b* values in the color determination after the refining. Peroxide value decreased from 2.64 to 0.55 meq/kg, p-Anisidine value increased from 2.41 to 3.41, TOTOX value decreased from 7.70 to 4.51, and free fatty acids decreased from 1.72 to 0.61 after the whole refining process. There was a removal of 64.5% of total phenolic content, 65.3% of total carotenoid content, 22.5% of phytosterol content and high retention of tocopherol content in kenaf seed oil after refining. Kenaf seed oil showed an increasing of 84.5% and 58.6% in DPPH value and ABTS+ value, respectively. Oleic acid was found in the largest amount in the refined kenaf seed oil (35.1%), followed by linoleic acid (32.3%) and palmitic acid (21.9%). There was a slight increase in unsaturated fatty acids and a slight decrease in saturated fatty acids after refining. This work showed that the chemical refining process offers an improvement in the quality of kenaf seed oil

Oxidative stability of sunflower oils supplemented with kenaf seeds extract, roselle seeds extract and roselle extract, respectively under accelerated storage

With the concern of adverse effects of lipid oxidation on food deterioration and human health, the antioxidant activities of kenaf seed extracts (KSE), roselle seed extracts (RSE) and roselle extracts (RE) were evaluated by comparing its oxidative stability in refined, bleached & deodorised (RBD) sunflower oils with that of in synthetic antioxidant, BHA. Established methods such as peroxide values (PV), p-anisidine values (AV), TOTOX values, free fatty acids (FFA), iodine values (IV), total phenolic contents (TPC), conjugated dienes (CD) and conjugated triene (CT) were employed to assess the extent of oil deterioration. During 24 days storage, consensus was accomplished based on the results assessed by PV, TOTOX, CD, CT, IV and TPC at which the antioxidant activities of KSE, RSE and RE were better than BHA. Surprisingly, the results obtained by AV and FFA assays showed the reversed. Among the extracts, RSE exhibited the best antioxidant activities. These suggest that KSE, RSE and RE may be used as potential source of natural antioxidants in the application of food industry to prevent lipid oxidation

Functional properties of roselle (Hibiscus sabdariffa L.) seed and its application as bakery product

Roselle (Hibiscus sabdariffa L.) seed is a valuable food resource as it has an excellent source of dietary fibre. Therefore, this study examined the functional properties of roselle seeds. Replacement of cookie flour with roselle seed powder at levels of 0–30 % was investigated for its effect on functional and nutritional properties of cookies. Among the four formulations cookies, the most preferred by panelists was 20 % roselle seed powder cookie (F3), followed by 10 % roselle seed powder cookie (F2) and 30 % roselle seed powder cookie (F4). The least preferred formulation among all was control cookie (F1). Cookie with 20 % roselle seed powder added showed higher content of total dietary fibre (5.6 g/100 g) as compared with control cookie (0.90 g/100 g). Besides that, cookies incorporated with roselle seed powder exhibited improved antioxidant properties. Thus, roselle seed powder can be used as a dietary fibre source and developed as a functional ingredient in food products

In-situ crosslinking of Aspergillus flavus lipase: improvement of activity, stability and properties

The mycelium-bound lipase of Aspergillus flavus was stabilised by cross-linkage using glutaraldehyde or methylglyoxal. Lipase activity was enhanced by up to 48% by treatment with methylglyoxal but not by glutaraldehyde. Cross-linking with methylglyoxal increased the thermal stability of the lipase by 58% at 50°C