Effect of seaweed Kappaphycus alvarezii in the synthesis of Cu@Cu2O core–shell nanoparticles prepared by chemical reduction method

This study aims is to investigate the influence of different concentrations of Kappaphycus alvarezii (K. alvarezii) for the synthesis of Cu@Cu2O core–shell nanoparticles (NPs) in aqueous solution. The core–shell NPs were prepared by a chemical reduction method using K. alvarezii, CuSO4·5H2O, NaOH, ascorbic acid, hydrazinium hydroxide, as stabilizer, copper precursor, pH moderator, antioxidant and reducing agent under 120°C temperature, respectively. Formation of Cu@Cu2O-NPs was determined by UV–Vis spectroscopy where surface plasmon absorption maxima can be observed at 390-590 nm. The synthesized core–shell NPs were also characterized by X-ray diffraction. Moreover, the morphology and structure of the K. alvarezii/Cu@Cu2O-NPs were investigated by TEM, FESEM and EDXRF. The Fourier transform infrared spectrum suggested the complexation present between K. alvarezii and Cu@Cu2O-NPs. The study clearly showed that using various amounts of K. alvarezii leads to produce different ratios and sizes of Cu@Cu2O NPs. The size of the Cu@Cu2O-NPs decreased as the amount of K. alvarezii was increased. The ratio of Cu@Cu2O increases with the increasing concentration of K. alvarezii until 0.2 wt%

Effects of water addition level on physical properties, rheological profile and sensory evaluation of gluten-free bread : a preliminary approach

The amount of water in gluten-free recipes is very important to the quality of the end product. The research aimed to develop an alternative formula for gluten-free bread using different water levels. This research was conducted to determine the physical properties, rheological profile and sensory evaluation of natural gluten-free bread produced by adding different water levels to the recipe without adding hydrocolloid. Five types of bread with different levels of water at (A) 80%; (B) 90%; (C) 100%; (D) and control dough: 105% (control 1); (E) 60% (wheat breadcontrol 2) of the flour basis were investigated. Control 1 is the standard level of water for making gluten-free bread, while control 2 is the standard level of water for preparing wheat bread. Sample A has a lighter crust and crumbs, as well as a white index value and lower ΔE values comparable to wheat bread, better volume, increased pore size sharply and shows higher G’ and G”. G’ decreased as the amount of water in the dough increased. All dough formulations had higher gelatinisation enthalpy change (ΔH) values than sample A and sample E. The bakery sector could use the findings to design and reformulate the recipes of diabetic and/or reduced calorie and gluten-free bread recipes to better fulfill consumers’ expectations

Effects of different drying methods on the functional properties and physicochemical characteristics of chia mucilage powder (Salvia hispanica L.)

Chia seeds are a healthy source of omega-3 fatty acids and dietary fibre. The effects of different drying methods (freeze-drying and oven-drying) on the functional properties (water holding capacity, oil holding capacity and colour analysis) and physicochemical characteristics (scanning electron microscopy) of chia mucilage powder (Salvia hispanica L.) including comparison with xanthan gum, hydroxypropyl methylcellulose (HPMC), and arabic gum were investigated. Chia mucilage dried in a freeze dryer (FD) showed significantly higher (p<0.05) values of water holding and oil holding capacities compared to chia mucilage dried in air convection heat oven (ACHO), xanthan gum, HPMC and arabic gum. It also showed a higher L* value (lightness) than ACHO, HPMC, and xanthan gum but lower values of a*, b*, c*, BI, and ΔE than ACHO and xanthan gum. The morphology of FD is smaller, more uniform in size, with a fine fibrous relative structure compared to ACHO. FD is a novel mucilage that could potentially be used as a functional and environmentally friendly hydrocolloid for human consumption and significantly better than commercial hydrocolloids. These results can also help to select successful drying methods for food products based on their functional and physicochemical characteristics

Pengasingan dan pengesanan asid deoksiribonukleik (DNA) spesies haiwan menggunakan multipleks tindak balas rantaian polimerase (PCR) daripada minyak sapi

Kajian ini dijalankan untuk mengesan asid deoksiribonukleik (DNA) spesies haiwan dalam campuran minyak sapi menggunakan teknik tindak balas rantaian polimerase (PCR) multipleks. Kebolehdapatan DNA daripada produk berminyak membolehkan analisis PCR dijalankan dan sekaligus boleh menentukan kehadiran spesies haiwan produk tersebut dengan menggunakan primer haiwan yang khusus-spesies. Gen sasaran adalah DNA mitokondria (mtDNA) Sitokrom oksidase II (COII) untuk menentukan lembu, manakala mtDNA tRNA-ATP8 dan DNA nuklear (nDNA) Elemen Nuklear Berselang pendek (SINE) untuk menentukan babi. Terdapat satu kawalan (S1) dan tiga sampel campuran minyak sapi dengan gelatin babi ditambah pada kepekatan berbeza iaitu 1%, 3% dan 5% (w/v) (S2, S3 dan S4). Analisis PCR simpleks menggunakan primer spesies-spesifik yang disebutkan, berjaya mengamplifikasi DNA lembu dengan amplikon bersaiz 165 bp (COII) dan DNA babi dengan amplikon 212 bp (tRNA-ATP8) dan 161 bp (SINE). Manakala, teknik PCR multipleks yang telah dioptimumkan menggunakan primer mtDNA (tRNA-ATP8) dan nDNA (SINE) untuk menentukan kehadiran haiwan babi, juga menghasilkan amplikon bersaiz yang sama. Oleh itu, kajian menunjukkan bahawa kaedah PCR multipleks adalah kaedah yang mudah, ringkas dan pantas untuk menentukan kehadiran DNA babi di dalam sampel campuran produk minyak sapi selain daripada kaedah PCR simpleks

Effects of gold nanoparticles synthesized using water extract of brown seaweed; Sargassum glaucescens

Based on data published in April 2011 by WHO about Deaths in worldwide, cancer is the third leading cause of death (after heart disease and stroke) in most of developed countries and the second leading cause of death (after heart disease) in Malaysia . Therefore, one of the challenges for Malaysia and the whole world is carrying out research on cancer in order to find its causes and method for therapy and prevention of this disease. Metal nanoparticle synthesis using seaweed extract shows rapid and non-toxic process which resulted to nano sizes having the greatest potential for biomedical applications. The current study was aimed to investigate the anticancer properties of gold nanoparticles synthesized using water extract of brown seaweed; Sargassum glaucescens(Au/S.G-NPs). The effect of 3.65±1.69 nm Au/S.G-NPs were studied on HeLa (cervical cancer) and 3T3 (mouse fibroblast) using tetrazolium dye MTT assay. Later on, in vitro apoptosis effect was evaluated using fluorescent microscopy, flow cytometry, and protease caspase activities. After 72 h treatment , MTT assay revealed highest and significant cytotoxic effect of Au/S.G-NPs dose and time-dependently against cervical cancer cells with IC50 of 4.75 ± 1.23 μg/mL. On the other hand, Au/S.G-NPs showed no cytotoxic effect toward mouse fibroblast cells. Moreover, Au/S.G-NPs significantly (P < 0.05) arrests HeLa cells at G2/M phase and significantly (P < 0.05) activated caspases-3 and -9. The results revealed that Au/S.G-NPs can be further developed as chemotherapeutic compound for the treatment of cancers especially cervical cancer

Reduction of Saturated Fat in Dark Chocolate using Sacha Inchi (Plukenetia volubilis) Oil Oleogel

This research studied the effectiveness of Sacha Inchi Oil Oleogel (SIOO) as a partial replacement for saturated fat in dark chocolate. Sacha inchi (Plukenetia volubilis) oil is high in polyunsaturated fatty acids (α-linolenic and linoleic acids) and a good source of tocopherols. This study prepared oleogels using sacha inchi oil as a base oil and food-grade beeswax as an oleogelator. Different percentages of SIOO (1%, 2.5% and 5.0%) were added in the dark chocolate. Dark chocolate without SIOO was used as a control. Fatty acid profile, total polyphenols, antioxidant activity and sensory evaluation of the formulated dark chocolates with SIOO were investigated. The incorporation of SIOO significantly (p&lt;0.05) lowered the saturated fat and increased the polyunsaturated fatty acids in dark chocolate samples. This study also showed that the total polyphenols and antioxidant activity of dark chocolates enriched with 2.5 and 5.0% SIOO were significantly higher (p&lt;0.05) than the other chocolate samples. Sensory evaluation showed that control and dark chocolates added with SIOO (1% and 2.5%) received similar scores for all sensory attributes. However, the highest concentration of SIOO decreased significantly (p&lt;0.05) the scores for the taste and overall acceptability of dark chocolate. Therefore, the enrichment of sacha inchi oil oleogel as a functional ingredient could reduce the saturated fat and increase the polyunsaturated fatty acids and antioxidant activity of the formulated dark chocolate, which is well-accepted by consumers

Representative candidate of gelatinase encoded gene in Enterobacter aerogenes (Strain EA1) for hydrolyzing porcine gelatin

Enterobacter aerogenes (Strain EA1) was characterised as gelatinase species-specific bacterium to porcine and fish gelatin. This bacterium offers the possibility of enzymes production to each species gelatin. In this study, a bioinformatic analysis toward genome sequence of E. aerogenes was perfomed to determine genes encoded for gelatinase. E. aerogenes were partially genome sequenced resulting in 5.0 mega basepair total size of sequence. From pre-process pipeline, 78.58% of high quality reads was obtained for E. aerogenes. Genome assembly produced 120 contigs with 55.17% of GC base content. Protein prediction analysis determined 4705 genes from E. aerogenes. Two gelatinase candidate target genes selected from E. aerogenes were NODE_9_length_26866_cov_148.013245_12 containing 1029 bp sequence and NODE_24_length_155103_cov_177.082458_62 containing 717 bp sequence with highest similarity identity percentage against gelatinase enzyme available in Swiss-Prot and NCBI online database. Then, primers were designed for each target genes based on the open reading frame of selected genes. The expected gene candidate showed, 1029 bp and 717 bp amplicons for gen NODE_9_12 and gene NODE_24_62, respectively. Thus, gelatinase candidate encoded genes of E. aerogenes were identified for hydrolyzing porcine gelatin

Effect of processing on bread quality

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Optimization and characterization of chia seed (Salvia hispanica L.) oil extraction using supercritical carbon dioxide

Quality of chia seed (Salvia hispanica L.) oil obtained by supercritical carbon dioxide (SC−CO2) is compared with Soxhlet extraction and commercial cold-pressed oil. Response surface methodology (RSM) was conducted to determine the effect of different extraction parameters (pressure, temperature, and grinding time of chia seed) on chia seed oil yield. Linear and quadratic terms of pressure, temperature, and different particle sizes (various grinding times) significantly affected the amount of chia seed oil. The optimal extraction conditions using SC−CO2 to obtain the maximum yield of chia seed oil were as follows: chia seed particle size of 100−400 μm, 24 s of grinding time, extraction pressure of 335 bar and extraction temperature of 45 °C. However, the oil yield of chia seed extracted by SC−CO2 was lower than Soxhlet. Images captured by field emission scanning electron microscopy (FESEM) found a cracked surface in defatted chia seed powders with mostly oil released when high-pressure SC−CO2 is applied. Based on the optimized conditions, chia seed oils obtained by SC−CO2 and Soxhlet had comparable oxidation value, fatty acid composition, thermal properties, tocopherols, and antioxidant activity compared to commercial chia seed oil. However, oxidative stability test shows chia seed oil is less protected against oxidation due to the large amount of polyunsaturated fatty acids (PUFAs) more than 85 %. The present study suggests that SC−CO2 extraction is an effective method to produce chia seed oil with excellent sources of PUFAs and tocopherols

Antioxidant properties of three banana cultivars (Musa acuminate ‘Berangan’, ‘Mas’ and ‘Raja’) extracts

The effect of solvent type in antioxidant compounds extraction from banana tissues was studied. The solvent system used was pure methanol, ethanol, acetone and their aqueous solution at 50% and 70% concentrations. Comparison among three common cultivars of banana in Malaysia (Berangan, Mas and Raja) had been done and their antioxidant activities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging system, ferric reducing ability in plasma (FRAP) assays and total phenolic content (TPC) assays. Acetone 70% had the strongest antioxidant compounds extraction power as compared to other solvent. All banana samples were found to be low in primary antioxidant but powerful secondary antioxidant source of fruit. The ascending order of banana cultivars in term of their antioxidant activities in all antioxidant assays carried out were Berangan 0.70) than FRAP-DPPH and TPC-DPPH assays due to the same mechanism that occurred in the reaction of FRAP and TPC assay