Dr Taiwo Akanbi

The Australian native plant, lemon-scented tea tree (LSTT) is rich in polyphenols with strong antioxidant activities. Encapsulation enhances the potential applications of plant extracts and additionally protects them from degradation. The encapsulating agent is one of the key elements in the encapsulation process. In this study, lemon pomace powder (LPP) was investigated as a new carrier agent for LSTT leaf phenolic extract, and its performance was compared with the commonly used polysaccharide (i.e., maltodextrin (MD)) and protein-based (i.e., soy protein isolate (SPI)) coating materials. The encapsulation efficiency, colour, polyphenol and antioxidant property retention, particle morphology, crystallinity, flow properties, and release behaviour in food simulants and gastrointestinal fluid were studied to compare the performance of the carrier agents individually and in combinations. The encapsulation efficiency of lemon pomace powder (LPP) was above 95 % and the order for the retention of polyphenol and antioxidant capacities were MD>LPP>SPI. LPP offers better flow properties and unique particle morphology, which was also amorphous in nature with some degree of crystallinity. The release profile in the food simulants showed a controlled and sustained release rate over the tested period, which was comparable with MD and SPI. In gastrointestinal fluids, the percent release followed the order of SPI>LPP>MD for the carrier agents. The incorporation of LPP with MD and SPI can improve several properties of the individual carrier agents. Thus, LPP can be used as a potential carrier agent for polyphenols in functional food formulation either on its own or in combination with other coating materials.

The processing and consumption of mango (Mangifera indica) generate a sizeable amount of kernel waste with enormous and largely unexplored potential, while by-products from njangsa (Ricinodendron heudelotii) seed and bush mango (Irvingia gabonensis) kernel oil extraction are often discarded. This study aims to repurpose these kernels and seed wastes into added/high-value products and evaluate the ethanolic and methanolic extracts of their pressed marcs for polyphenolic content and potential antioxidant activity. The total phenolic content (TPC) and total flavonoid content (TFC) in the marc extracts ranged between 47.87 and 376.0 mg GAE/g and 4.85 and 13.70 mg Rutin/g, respectively. Both mango kernel marc extracts showed higher potent reducing power, ABT¿+ radical and DPP¿ radical scavenging activities with half effective concentration (EC50) values (0.20¿0.22 mg/mL) comparable to the reference compound; ascorbic acid (0.20 mg/mL). The TPC and TFC of the marc extracts generally strongly correlated with antioxidant activity. Relatively higher contents of xanthophyll and ß-carotene were detected in bush mango kernel methanolic extract than in the other extracts. Extraction solvent affected the composition and content of bioactives in pressed marcs of njangsa seed and mango kernel.

The fatty acid (FA) profile, nutritional index, and thermal properties of lipids from Tenebrio molitor and Hermetia illucens larvae were studied. T. molitor and H. illucens larvae had high lipid contents (respectively 28.8% and 42.6%), saturated (25.0% and 55.8%), monounsaturated (MUFA) (39.2% and 28.3%), and polyunsaturated (PUFA) fatty acids (35.8% and 15.9%). Both larvae fats contained beneficial ¿-3, ¿-6, and ¿-9 FA. For T. molitor and H. illucens, the lipid nutritional indices were atherogenicity indices 0.68 and 2.75, thrombogenicity indices 0.58 and 0.74, and health-promoting indices 3.51 and 0.80 hypocholesterolemic/hypercholesterolemic acid ratio 1.38 and 0.23, suggesting the nutritional superiority of T. molitor larvae fat. Regioisomeric distribution analysis showed that PUFA in H. illucens larvae fat are concentrated on the sn-1,3 positions, whereas those in T. molitor larvae fat are distributed in all three positions. The thermal stability and crystallisation profiles differed for both larvae fats and demonstrated their potential use in thermally processed foods.

Lipids possess numerous and diverse applications as nutritional, bioactive and techno-functional components of foods. However, their propensity to oxidize, react with other food constituents, negatively modify their properties and attendant losses in food value and quality as well as their link to pathogenesis of several degenerative diseases continue to be of concern and make them an object of research attention. In this review, we highlight significant advances and current knowledge in controlling and/or minimizing oxidation during processing, storage and formulation, preserving functionalities and enhancing nutritional value in light of increasing interest from government, food industry and consumers in novel lipid sources, natural product antioxidants and labeling/regulatory requirements.

The lemon-scented tea tree (LSTT) is an Australian native herb and is a rich source of essential oil and phenolics. The ETHOS X extraction system is known as a commercial microwave-assisted extraction (MAE) system for extracting bioactive compounds from plant materials. This study investigated the influence of soaking time, radiation time, microwave power, and sample to solvent ratio on the extraction efficiency of polyphenols and antioxidant properties from lemon-scented tea tree leaves and optimized the extraction conditions using response surface methodology (RSM). The effectiveness of ETHOS X was further compared with ultrasound-assisted extraction (UAE) and shaking water bath (SWB) techniques. The results revealed that soaking time did not significantly affect the recovery of phenolics from the leaves (p > 0.05). Thus, soaking is not required for the ETHOS X extraction of polyphenols from LSTT leaves. RSM was successfully applied to explore the impact of ETHOS X extraction conditions and optimize the extraction conditions. Radiation time significantly affects the recovery yield of phenolics (p < 0.05) positively, whereas irradiation power and sample to solvent ratio adversely influenced the extraction yields of phenolics. The optimal ETHOS X extraction conditions were: radiation time of 60 min, irradiation power of 600 W, and sample to solvent ratio of 2 g/100 mL. Under these conditions, 119.21 ± 7.09 mg of phenolic, 85.31 ± 4.55 mg of flavonoids, and 137.51 ± 12.52 mg of proanthocyanidins can be extracted from a gram of dried LSTT leaves. In comparison with UAE and SWB, ETHOS X is not more effective for the extraction of phenolics than UAE and SWB. However, this technique can save half of the solvent volume compared to UAE and SWB techniques.

Driven by consumer demand and government policies, synthetic additives in aquafeed require substitution with sustainable and natural alternatives. Seaweeds have been shown to be a sustainable marine source of novel bioactive phenolic compounds that can be used in food, animal and aqua feeds, or microencapsulation applications. For example, phlorotannins are a structurally unique polymeric phenolic group exclusively found in brown seaweed that act through multiple antioxidant mechanisms. Seaweed phenolics show high affinities for binding proteins via covalent and non-covalent bonds and can have specific bioactivities due to their structures and associated physicochemical properties. Their ability to act as protein cross-linkers means they can be used to enhance the rheological and mechanical properties of food-grade delivery systems, such as micro-encapsulation, which is a new area of investigation illustrating the versatility of seaweed phenolics. Here we review how seaweed phenolics can be used in a range of applications, with reference to their bioactivity and structural properties.

Pure concentrates of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were used to produce monoacylglycerol and diacylglycerol (MDG) oils via enzymatic glycerolysis in a solvent-free system. Immobilized lipase from Candida antarctica B (Novozym 435) was employed for the glycerolysis reaction with up to 90% product formation in one hour. This lipase also favoured diacylglycerol (DAG) over monoacylglycerol (MAG) production. Products were purified using silica gel chromatography and characterised by capillary chromatography with flame ionization detection (Iatroscan-FID). Purified products were added to extra virgin olive oil (EVOO) at a concentration of 20% w/w. The fortified olive oil was stabilized using hydroxytyrosyl palmitate, an antioxidant prepared by conjugating hydroxytyrosol with palmitic acid using Novozym 435 lipase. In vitro hydrolysis of the fortified oil was also carried out using porcine pancreatic lipase to investigate the mechanism of action of this enzyme on the oil mixtures.

Tenebrio molitor (mealworms) and Hermetia illucens (Black soldier fly) larvae were analysed for the effect of feed composition on the fatty acid profiles. The larvae were raised on various feeds to which the basal diet had been supplemented to various levels with seed meals (flax seed, chia seed, hemp seed, and rapeseed). Fatty acid classes and composition of both insect larvae were similar in T. molitor and H. illucens larvae fat; however, the actual percentage composition differed; saturated (28.61% and 86.75%), monounsaturated (MUFA) (52.89% and 7.94%), and polyunsaturated (PUFA) fatty acids (18.49% and 5.31%). The supplementation of the basal diet resulted in larvae fat with increased omega-3 fatty acids levels, and subsequently a lower omega-6 to omega-3 ratio (T. molitor; 4.28:1 in the diet with 10% chia seed, H. illucens; 3.52:1 in the diet with 20% hemp seed) than those of the basal diets (50:1 and 9.91:1 in T. molitor and H. illucens respectively). In most of the larvae samples, the ratio achieved was closer to that recommended for a healthy diet.

Microorganisms from extreme environments tend to undergo various adaptations due to environmental conditions such as extreme pH, temperature, salinity, heavy metals, and solvents. Thus, they produce enzymes with unique properties and high specificity, making them useful industrially, particularly in the food industries. Despite these enzymes' remarkable properties, only a few instances can be reported for actual exploitation in the food industry. This review's objectives are to highlight the properties of these enzymes and their prospects in the food industry. First, an introduction to extremophilic organisms is presented, followed by the categories and application of food enzymes from extremophiles. Then, the unique structural features of extremozymes are shown. This review also covers the prospective applications of extremozymes in the food industry in a broader sense, including degradation of toxins, deconstruction of polymers into monomers, and catalysis of multistep processes. Finally, the challenges in bioprocessing of extremozymes and applications in food are presented. Practical applications: Enzymes are important players in food processing and preservation. Extremozymes, by their nature, are ideal for a broad range of food processing applications, particularly those that require process conditions of extreme pH, temperature, and salinity. As the global food industry grows, so too will grow the need to research and develop food products that are diverse, safe, healthy, and nutritious. There is also the need to produce food in a sustainable way that generates less waste or maximizes waste valorization. We anticipate that extremozymes can meet some of the research and development needs of the food industry.

Complex coacervation is a highly promising microencapsulation technique that is extensively employed in pharmaceutical, food, agriculture and textile industries. The process involves the interaction of oppositely charged polyelectrolytes in aqueous form. High payload and high encapsulation efficiency (up to 99%), relatively lower cost of processing, ability to use food-grade shell materials and synthesis at ambient temperature makes coacervation an appropriate choice in food and agrochemical industries. Various works have been documented using different polymer systems and core-shell combinations. This review paper intends to summarize some of the recent advances in complex coacervation for use in the food and agriculture areas. Current status and future trends of plant proteins utilization for complex coacervation have been reviewed. It is expected that this review will be a useful resource for material scientists, food technologists and food engineers.

Candida antarctica lipase B-catalysed synthesis of lipophilic esters of polydatin was investigated along with their antioxidant activities. The effects of synthesis parameters such as solvent, substrate molar ratio, enzyme concentration, addition of molecular sieves, reaction temperature and time on the production of ester were studied and optimised. The highest production of esters was obtained with acetone as the reaction solvent. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and a-tocopherol. All polydatin esters inhibited the oxidative destruction of ß-carotene more effectively than did BHT and a-tocopherol. Results of thiobarbituric acid tests showed that in bulk fish oil, all esters were more effective than a-tocopherol at 2 mmol/kg concentration but were not as effective as BHT. In fish oil-emulsions, all esters were more effective than both BHT and a-tocopherol at 2 mmol/kg concentration. The synthesized polydatin esters are promising antioxidants for oil/fat-based foods.

The incorporation of bioactive macromolecules from natural sources into marketable functional foods and nutraceuticals is of major significance to the agri-food sector. Interest in this area of research stems from the application of purified bioactive macromolecules in enhancing food quality and as an alternative to some pharmaceutical drugs for delivery of potential health benefits, with less associated adverse effects. To obtain bioactive macromolecules of high quality, appropriate use of extraction techniques and its influence on sensory and physicochemical properties is paramount. With the advent of technology-aided processes, there has been remarkable improvement in the extraction efficiency of these bioactive agents. An overview of the influence of these new techniques on extraction efficiency and physicochemical properties of proteins, lipids and fibers, which this detailed review provides, will prove to be a valuable resource to food industries aiming to maximize production of bioactive macromolecules from natural sources as well as the scientific community.

In this work, Candida antarctica lipase A was applied to selectively remove saturated fatty acids from palm oil to prepare palm oil acylglycerol concentrate (POAC), where palmitic acid decreased from 40.0 to 28.7% and oleic acid increased from 40.0 to 50.5% after 3 h of hydrolysis. Lipozyme RMIM from Rhizomucor miehei was then used to incorporate either alpha linolenic acid (ALA) or eicosapentaenoic acid (EPA) into the resulting POAC. Optimum omega-3 incorporation was achieved when POAC to omega-3 ratio was 6:3, reaction temperature was 40 °C and reaction time was 18 h. Under these conditions, the ALA content in the separated ALA incorporated structured lipid (POAC-ALA) was 27.1%, and the EPA content in the EPA incorporated structured lipids (POAC-EPA) was 30.9%. The formed structured lipids had lower levels of saturated fatty acids, and significantly lower melting points, in both cases below 8 °C. The enzymatic process developed produces new structured lipids, with lower saturated fat and higher omega-3, with potential as a healthy palm oil derived lipid ingredient.

In this study, several lipophilic hydroxytyrosyl esters were prepared enzymatically using immobilized lipase from Candida antarctica B. Oxidation tests showed that these conjugates are excellent antioxidants in lipid-based matrices, with hydroxytyrosyl eicosapentaenoate showing the highest antioxidant activity. Hydroxytyrosyl eicosapentaenoate effectively stabilized bulk fish oil, fish-oil-in-water emulsions and microencapsulated fish oil. The stabilizing effect of this antioxidant may either be because it orients itself with the omega-3 fatty acids in the oil, thereby protecting them against oxidation, or because this unstable fatty acid can preferentially oxidise, thus providing an additional mechanism of antioxidant protection. Hydroxytyrosyl eicosapentaenoate itself was stable for one year when stored at -20 ¿C.

Nuclear magnetic resonance (NMR) spectroscopy and chromatography, particularly thin layer chromatography with flame ionisation detector (TLC-FID), were used to investigate fish oil adulteration of krill oil with ethyl esters and triacylglycerol. Natural krill oil has higher levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in phospholipid than in triacylglycerol and so high levels of these omega-3 fatty acids in krill oil triacylglycerol was indicative of adulteration. Carbon (13C) NMR detected adulteration of krill oil with 10% or more anchovy oil, while TLC-FID detected levels as low as 1% adulteration with EPA ethyl esters. However, positional distribution of EPA and DHA, as determined using 13C NMR, was similar for both fish oil and krill oil, indicating that positional distribution cannot be used to show adulteration. Phosphorous (31P) NMR spectroscopy can show adulteration with low cost sources of phospholipid but was not useful for determining adulteration of krill oil with fish oil.

The seaweed industry is a multi-billion venture, owing to the plethora of products that can be obtained from it, including hydrocolloids (as thickening and gelling agent); biomass for fuel, fertilizer, animal feed additives; biomolecules for cosmetics; and food-grade pigments. Seaweeds such as red algae, brown algae, and green algae are an excellent source of a large range of natural food colours which imparts sensorial and health properties to food. The type, amount, and biochemical compositions, and biological properties of seaweed pigment are highly variable, and these characteristics affect the choice of protocol useful for extracting these pigments. Techniques for the recovery of seaweed pigments in worthwhile owing to the growth in interest of natural food colours that also provide health benefits.

The fatty acid selectivity of Candida antarctica lipase A (CAL-A) was applied to produce DHA concentrate by controlling the rate and extent of hydrolysis. Calcium was utilized to achieve a higher degree of hydrolysis. CAL-A was not regioselective but rather fatty acid selective, showing sequential selectivity for saturated, monounsaturated and polyunsaturated fatty acids in the order of increasing double bonds. Based on its strong initial preference for saturates, CAL-A was used to concentrate 82% docosahexaenoic acid (DHA) and 11% omega-6 docosapentaenoic acid (DPA-n6) after partial hydrolysis of algal oil. Thermomyces lanuginosus (TL 100L) lipase was used to partially remove DPA-n6, further concentrating DHA to 89%. CAL-A was immobilized on octadecyl-activated resin without altering its fatty acid selectivity.

Anchovy oil was selectively partially hydrolysed at 30% and 60% using Thermomyces lanuginosus lipase (TL 100L) to produce EPA and DHA concentrates. These concentrates were subsequently microencapsulated into ¿multi-core¿ microcapsules using complex coacervation. Microcapsules produced from these concentrates were significantly more stable than those produced from unconcentrated anchovy oil, even though the concentrated oils themselves were significantly less stable than anchovy oil. Morphological and physicochemical analysis indicated that the microcapsule from concentrates exhibits significantly smoother surfaces and improved mechanical strength in addition to enhanced oxidative stability compared to the microcapsules fabricated from native anchovy oil.

The lipid profile, in vitro digestion and oxidative stability of mutton bird oil were investigated. Wax ester, triacylglycerol and sterol were the major lipids present as determined using capillary chromatography with flame ionisation detector (Iatroscan). Fatty acid analysis by gas chromatography (GC) showed that wax esters had a higher total omega-3 fatty acids content including EPA, DPA and DHA than TAGs (31¿% and 24¿%, respectively). In TAGs, 13C nuclear magnetic resonance (NMR) data showed that EPA was statistically positioned at sn-1,3 and sn-2, while DHA was preferentially at sn-2. In vitro digestion using porcine pancreatic lipase resulted in 75¿% of TAG and 10¿% wax ester hydrolysis in 120¿min. As reflected in the measured conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS) values during accelerated oxidation at 60¿°C for 5¿days, the oil was relatively stable against oxidation considering its high omega-3 content.

Lipases, which can be immobilized and reused for many reaction cycles, are important enzymes with many industrial applications. A key challenge in lipase immobilization for catalysis is to open the lipase lid and maintain it in an open conformation in order to expose its active site. Here we have designed "tailor-made" graphene-based nanosupports for effective lipase (QLM) immobilization through molecular engineering, which is in general a grand challenge to control biophysicochemical interactions at the nano-bio interface. It was observed that increasing hydrophobic surface increased lipase activity due to opening of the helical lid present on lipase. The molecular mechanism of lid opening revealed in molecular dynamics simulations highlights the role of hydrophobic interactions at the interface. We demonstrated that the open and active form of lipase can be achieved and tuned with an optimized activity through chemical reduction of graphene oxide. This research is a major step toward designing nanomaterials as a platform for enhancing enzyme immobilization/activity.

Partial hydrolysis of emu oil was performed using Thermomyces lanuginosus lipase to remove some shorter chain fatty acids. Then eicosapentaenoic acid (EPA) was incorporated into the modified emu oil using either Lipozyme RMIM or Lipozyme TLIM to produce new EPA enriched structured lipids. Using Isooctane as a reaction solvent increased the level of EPA incorporation, which was higher with RMIM than with TLIM. TLIM incorporated EPA almost exclusively into the sn-1,3 positions, whereas RMIM incorporated EPA at sn-1,3 and sn-2 positions in an almost statistical ratio. Both structured lipids were less oxidatively stable than emu oil.

The enzymatic hydrolysis of canola, anchovy and seal oils with different types and amounts of polyunsaturated fatty acids was measured using porcine pancreatic lipase (PPL) to establish the fatty acid selectivity of PPL. Substrates were subjected to the same conditions of hydrolysis, with percent hydrolysis monitored using Iatroscan and fatty acid selectivity monitored using gas chromatography (GC). Regardless of their distribution on the glycerol backbone, as monitored by 13C nuclear magnetic resonance (NMR), a-linolenic acid (ALA) and docosapentaenoic acid (DPA) were rapidly cleaved by PPL while eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and stearidonic acid (STA) were hydrolysed more slowly. Results show that PPL preferentially hydrolyses ALA and DPA over EPA, DHA and STA, and this selectivity is due to fatty acid rather than regioselectivity. The primary structural factor associated with resistance to PPL appears to be the distance of the first double bond from the ester linkage being hydrolysed. © 2014 Published by Elsevier Ltd.

The selectivity of anchovy oil hydrolysis was optimised for Thermomyces lanuginosus lipase, so that docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were concentrated and partially separated from each other. Enzyme concentration and pH control were important factors for effective hydrolysis. Monitoring percent hydrolysis using capillary chromatography with flame ionisation detector (Iatroscan) and fatty acid selectivity using gas chromatography (GC) indicated that during hydrolysis DHA primarily remained on the glycerol backbone, while EPA was progressively removed. 13C nuclear magnetic resonance (NMR) data showed that selectivity of hydrolysis was primarily due to fatty acid selectivity and not regioselectivity, with hydrolysis from both sn-1,3 and sn-2 sites being equally favoured. © 2012 Elsevier Ltd. All rights reserved.

We report that the hydrolytic performance of Thermomyces lanuginosus lipase, TLL, and its selectivity towards concentrating clinically important omega 3 fatty acids was increased by the addition of a protic ionic liquid, pIL, Triethylammonium mesylate, TeaMs. We show that TeaMs has a structure altering effect on TLL, changing both the secondary and tertiary structure of TLL. The thermal activity of TLL was also significantly enhanced by the addition of TeaMs. © 2012 The Royal Society of Chemistry.

This study investigated the effects of carcass conditioning on shear force values and water holding capacity of various major skeletal muscles (Infraspinatus, Supraspinatus, Triceps brachii, Longissimus dorsi, Rectus femoris, Vastus lateralis, Semitendinosus, Semimembranosus and Adductor femoris) obtained from a total of 18, 1 year old Malaysian Indigenous rams. It also studied the effect of conditioning on changes in their pH and glycogen contents. Sequel to the conditioning, muscle samples were analysed for shear force values and water holding capacity. The postmortem conditioning resulted in significant decline (p>0.05) in muscle pH, glycogen, shear force values and drip loss while the cooking loss remained unaffected. Statistically, there was no interaction (p>0.05) between the conditioning period and muscle type and this indicates that the effects of conditioning on muscle pH, shear force values, drip loss and cooking loss were independent of the muscle type. Meanwhile, its effect on glycogen was influenced by the muscle type. © Medwell Journals, 2011.

Proximate compositions, culinary and sensory properties of noodles prepared from proportionate combinations of breadfruit starch and wheat flour were investigated. Breadfruit starch (BS) isolated from matured breadfruit (Artocarpus altilis) was used to produce noodles in combination with hard red wheat flour (WF) at a ratio of 100% WF:0% BS, 80% WF:20% BS, 60% WF:40% BS, 40% WF:60% BS, 20% WF:80% BS. The protein, fat, ash, crude fibre and moisture contents of the Breadfruit starch-Wheat flour (BSWF) noodles prepared from the above blends ranged from 0.65 to 10.88%, 0.35 to 3.15%, 1.28 to 2.25%, 1.18 to 1.45% and 4.65 to 5.45%, respectively. The contents of protein, fat, ash and crude fibre increased as the percentage breadfruit starch decreased. However, values of moisture content did not follow the same trend, instead higher values were found for 100% BS:0% WF (5.35%) and 20% BS:80% WF (5.45%). The cooking yield of the BSWF noodles ranged from 21.02 (60% BS:40% WF) to 23.75 g (100% BS:0% WF), cooking loss ranged from 5.49 (20% BS:80% WF) to 9.19% (100% BS:0% WF), while swelling index ranged from 3.1 (20% BS:80% WF) to 3.4 (100% BS:0% WF). Throughout the study, noodles produced from blends of 20% breadfruit starch and 80% wheat flour showed superior proximate, culinary and sensory attributes. © 2008 IFRJ, Faculty of Food Science & Technology, UPM.

The objective of this study was to determine the level of preservatives and microbiological loads in various brands of commercially available chili bo (paste). Fifteen different brands of chili bo obtained from the local market and hypermarkets were analyzed for pH, moisture and benzoic acid content, microbiological loads (aerobic, anaerobic, aerobic spores, and fungi), and thermophilic microorganisms. Results showed that both moisture content and pH vary among samples. The concentrations of benzoic acid detected in chili bo were found to be in the range of 537 to 5,435 mg/kg. Nine of fifteen brands were found to exceed the maximum level permitted by the Malaysian Food Law in accordance with the Codex Alimentarius (1,000 mg/kg for benzoic acid). An apparent correlation between benzoic acid concentration and microbiological loads present in the chili bo was observed. The microbiological loads were found to be relatively low in the end products containing high amounts of benzoic acid. The heat-resistant (70 to 80°C) microorganisms present in chili bo were identified as Ochrobacterum tritici, Stenotrophomonas rhizophila. Microbacterium maritypicum. Roseomonas spp., CDC group II-E subgroup A, Flavimonas oryzihabitans, and Pseudomonas aeruginosa, with M. maritypicum being the most frequently found (in 9 of 15 samples) microorganism. Most of these identified microorganisms were not known to cause foodborne illnesses. Copyright ©, International Association for Food Protection.

The activities of lipase produced by five lipases-producing thermophilic bacteria strains (SY1, SY5, SY6, SY7 and SY9) isolated from Selayang Hot Spring in the western part of Peninsular Malaysia were analyzed and compared. SY7 and SY9 had considerably higher lipolytic activities than those of SY1, SY5 and SY6. Thermostabilities of lipase produced by all strains were determined after heating at 80°C for 30 minutes. Strain SY7 retained the highest lipolytic activity of 77°, while others had infinitesimally low thermostability (retaining less than 34° of their original activity) at the same temperature and time. SY7 was chosen for further characterization because it showed exceptionally high lipase activity and thermostability. It was identified as belonging to Bacillus species by the conventional Gram-staining technique, Biochemical tests and Biolog Microstation system. By using 16S rRNA gene sequencing, strain SY7 generated the same expected PCR product with molecular weight of 1500 base pair. It displayed 98° sequence similarity to Bacillus cereus strain J-1 16S rRNA gene partial sequence with accession number: AY305275 and has been deposited in the database of Genbank.

Eleven lipase-producing thermophilic bacteria strains were recently isolated from Kuala Woh Hot Spring, in Peninsular Malaysia. These strains have been qualitatively screened using Rhodamine B-olive oil plate agar. All strains showed lipase activity in the range of 0.56-2.62 U/ml. Their thermostabilities were then determined by incubation at 80°C for 30 min. Results showed that strain KW 6 and KW 12 produced relatively thermostable lipases, which retained 62 and 54% of their original activity, respectively. They were identified based on their morphological characteristics, biochemical tests and the Biolog system. Strain KW 12 showed exceptionally unique characteristics (over KW 6) being able to grow in a broad range of pH and temperature. It was further identified using 16S rRNA partial sequence analysis and the result of 16S rRNA partial sequence analysis identified KW 12 as Anoxybacillus kamchatkensis. © Springer Science+Business Media B.V. 2009.

This study was carried out to determine the proximate, functional and pasting properties of breadfruit starch. Breadfruit starch was isolated from matured breadfruit (Artocarpus altilis) and was analyzed for its functional, proximate and pasting properties. The starch contains 10.83%, 0.53%, 0.39%, 22.52%, 77.48% and 1.77% moisture, crude protein, fat, amylose, amylopectin and ash contents respectively. The average particle size, pH, bulk density and dispersibility of the breadfruit starch were 18 µm, 6.5, 0.673 g/mls, and 40.67% respectively. The swelling power of the breadfruit starch increases with increase in temperature, but there was a rapid increase in the swelling power from 70 to 800C. The pasting temperature of the starch paste was 84.050C, setback and breakdown values were 40.08 and 7.92 RVU respectively. The peak viscosity value was 121.25 RVU while final viscosity value was 153.42 RVU. This study concluded that breadfruit starch has an array of functional, pasting and proximate properties that can facilitate its use in so many areas where the properties of other starches are acceptable. © All Right Reserved.