Nata De Coco Research Articles

Pretreatment of microcrystalline cellulose flakes with CaCl 2 increases the surface area, and thus improves enzymatic saccharification

Glucose production from cellulose flakes with cellulases was improved after pretreatment with saturated CaCl 2 at room temperature. When pretreated microcrystalline cellulose flakes (Funacel II, Funakoshi Co., Ltd, Tokyo, Japan) were saccharified with the cellulases, 76.8% of the substrate was converted into glucose within 5 h, whereas the corresponding conversion rate of water-pretreated cellulose flakes was 33.8%. To clarify the mechanism of the promotion, cellobiohydrolase I purified from Trichoderma longibrachiatum was used as the model cellulase, which degraded CaCl 2-pretreated cellulose more quickly than the water-pretreated cellulose under tested conditions. The maximum amount of the enzyme bound to CaCl 2-pretreated cellulose at 37 °C was estimated as 1.14 nmol/mg of cellulose, whereas that to water-pretreated cellulose was 0.527 nmol/mg of cellulose. The specific activity of the bound enzyme greatly decreased with the increase of the surface density ( ρ) of the bound enzyme, and no significant positive effects of the CaCl 2-pretreatment on the specific activity could be observed at the same ρ value, suggesting that the promotion was attributed mainly to the increase of the surface area of cellulose. The effect was also observed with dewaxed cotton or filter paper, but not with nata de coco cellulose or bagasse cellulose as the substrates. This suggests that the CaCl 2-pretreatment serves to increase the surface area of cellulose flakes via liberation of cellulose particles which were artificially aggregated during harsh drying processes of the flakes.

Acetobacter cibinongensisBacteremia in Human

<i>Acetobacter cibinongensis</i>Bacteremia in Human

Development of Functional Foods in the Philippines

Filipinos have traditionally recognized that some foods have benefits beyond nutrition although the term “functional foods” is new to them. Various studies show the nutritional and medical benefits of common Philippine foods. This paper reviews the functional attributes of selected traditional Philippine foods such as rice (Oryza sativa L.), coconut (Cocos nucifera L.), legumes [mungbean [Vigna radiata L. Wilczek]) and indigenous legumes], selected native vegetables (Momordica charantia and Moringa olifeira), root crops (sweetpotato (Ipomoea batatas), greater yam (Dioscorea alata) and taro (Colocasia esculenta)] and fruits [mango (Mangifera indica), papaya (Carica papaya), banana (Musa sp.) and pineapple (Ananas comosus)]. Processed food products with functional attributes include nata de coco and achara or pickled grated papaya. Germination and fermentation processes have been shown to improve the health benefits of some foods. Increasingly becoming popular are food products promoted with health benefits such as fermented milk drinks, yoghurt with lactobacillus, spirulina cereal, ganoderma coffee, milk with Bifidobacteria, etc. Evaluation of food products that qualify as functional foods on a scientific basis is done under the existing regulations of the Bureau of Food and Drugs of the Philippines Department of Health. Concerned government agencies have been involved in technical consultation meetings in the Asian region aimed at harmonizing the standards for regulating functional foods in the region. From this review, more studies are recommended on the functional attributes of Philippine traditional foods and newly developed ones, to establish their health benefits and determine the recommended amount and frequency of intake needed to obtain the benefits. An information campaign on functional foods among consumers and the general public should be conducted to enable them to enjoy the benefits of food “beyond nutrition.”

Effects of cereal and nata de coco supplementation on serum lipids in human

Effects of cereal and nata de coco supplementation on serum lipids in human

Growth of Human Keratinocytes and Fibroblasts on Bacterial Cellulose Film

Thin films of bacterial cellulose (BC) from a nata de coco culture system were developed, characterized, and investigated for the growth of human keratinocytes and fibroblasts. The average pore diameter and total surface area of the dried BC films estimated by BET were 224 A and 12.62 m(2)/g, respectively. With an film thickness of 0.12 mm, the average tensile strength and break strain of the dried films were 5.21 MPa and 3.75%, whereas those of the wet films were 1.56 MPa and 8.00%, respectively. The water absorption capacity of air-dried film was 5.09 g water/g dried films. For uses in the therapy of skin wounds, the potential biological mechanism of action of BC film was evaluated by using human keratinocytes and fibroblasts. Our results were the first direct demonstration that BC film supported the growth, spreading, and migration of human keratinocytes but not those of human fibroblasts. Expressions of E-cadherin and the alpha-3 chain of laminin confirmed the phenotype of human keratinocytes on BC film.

Development and production of cholesterol-lowering Monascus-nata complex

This study develops a new foodstuff, the Monascus-nata complex, which combines the functions of cholesterol-lowering monacolin k and bacterial dietary-fibre. Two Monascus strains, M. ruber and M. pilosus were fermented within cubical bacterial cellulose, nata de coco, obtained from Acetobacter fermented coconut juice, in a conditioned medium. The production levels and stability of monacolin k in the cultured Monascus-nata complex were determined to develop optimal fermentation conditions. The results indicated that a medium that comprised 5% glucose and 1.5% ammonium phosphate at pH 6.0–7.0 produced the most monacolin k (157 mg/l) for Monascus pilosus NCHU M-35. However, monosodium glutamate (MSG) and 0.001% ZnSO4 inhibited the intracellular accumulation of monacolin k. Monacolin k within the Monascus-nata complex was relatively resistant to washing and changes of pH, but thermal processing and freezing storage markedly reduced the amount present. This novel Monascus-nata complex is potentially a healthy foodstuff.

Acetobacter xylinum: An Inquiry into Cellulose Biosynthesis

Cellulose is the most abundant natural polymer on Earth. It is the major constituent of higher plants, and cellulose fibers have important industrial applications including the clothing that we wear and even the paper upon which this article is written. Cellulose forms the cell wall of eukaryotic plants, algae and fungi, and is synthesized by a variety of bacteria, including Acetobacter xylinum. A. xylinum, a Gramnegative bacterium found in the soil, can frequently be isolated from decaying fruit such as apples that have fallen to the ground. In addition to serving as a model organism for the study of cellulose synthesis, A. xylinum can serve as an interesting and instructive organism in the classroom to help students understand the process of science. The major focus of this article will be upon how students can experiment with A. xylinum using an inquiry approach to their learning. Acetobacter xylinum is an aerobic soil bacterium in the family of bacteria that ferments carbohydrates to vinegar (A. aceti). A. xylinum is an unusual member of this family because it synthesizes and extrudes fibrils of cellulose as part of the metabolism of glucose. The glucose subunits that form the cellulose microfibril are extruded through pores in the cell wall of the bacteria. In standing laboratory culture of the bacteria, the cellulose fibrils bundle together to form a mat or pellicle within which the bacteria are held. The pellicle floats on the surface of the medium allowing the bacteria to obtain plenty of oxygen, which they require for growth, multiplication, and more cellulose synthesis. Cellulose biosynthesis by A. xylinum may serve the bacterium in a number of ways in their microenvironment. These may include holding the bacteria at the air interface to ensure adequate oxygen, protection from ultraviolet radiation, protection from desiccation by holding water, acting as a biofilm to hold the organisms on substrates that they may be decomposing, and/or possibly providing protection from predators or competitors. Cellulose synthesis occurs as a multi-step series of chemical reactions beginning with glucose that is catalyzed by enzymes. The pathway is believed to be as shown in Figure 1. Cellulose is considered to be a secondary metabolite, which the organism synthesizes when major nutritional needs are met. There is genetic and molecular evidence that cellulose synthesis in A. xylinum is under operon control. Some practical applications of bacterial cellulose include: sensitive diaphragms for stereo headphones, thickeners for foods, paint, ink and adhesives. It has also been used as short term protection for burned skin prior to skin grafting. Most commercial applications of cellulose produced by Acetobacter have employed static batch culture to produce sheets of cellulose that can be sterilized to kill the bacteria and washed to remove microbial waste product contaminants. One large scale commercial application is the production of bacterial cellulose in a nonaseptic medium of sugar-enriched coconut milk in the Philippines, yielding an edible product called nata de coco. This food product has become popular in Japan as a high-fiber, low-calorie food. Recently, Japanese investigators have developed a technique to harvest Acetobacter cellulose from shallow culture pans with a windup roller device to pull the cellulose slowly from the surface of the culture medium. High yield commercial production of bacterial cellulose will require agitated (shaking) culture techniques. There has been some limited success in the laboratory studies producing cellulose in this way, but, at present, there are no commercial applications of this process.

Improved production of bacterial cellulose and its application potential

Bacterial cellulose, produced by Acetobacter species, displays unique properties, including high mechanical strength, high water absorption capacity, high crystallinity, and an ultra-fine and highly pure fibre network structure. It is expected to be a new commodity biochemical with diverse applications, if its mass production process could be improved, especially via submerged fermentation technology. It has already found application as a food matrix (nata de coco) and as dietary fibre, as a temporary dressing to heal skin burns, as an acoustic or filter membrane, as ultra-strength paper and as a reticulated fine fibre network with coating, binding, thickening and suspending characteristics. A wet spinning process for producing textile fibres from bacterial cellulose has also been developed, and applications as a superconducting and optical fibre matrix are under study. We have been able to improve bacterial cellulose production in surface culture (up to 28 g/l), as well as in submerged culture (up to 9 g/l) via strain selection, mutation, medium composition optimization and physico-chemical fermentation parameter control. Glucose and fructose as the carbon source and acetic acid as the energy source, combined with a precise control of pH and dissolved oxygen levels, results in highly improved cellulose yields. An internal pH control in stationary surface cultures was achieved by an appropriate choice of the ratio of fructose/glucose/acetic acid. It was also demonstrated that cellulose formation could be enhanced by adding insoluble microparticles such as diatomaceous earth, silica, small glass beads and loam particles to submerged, agitated/aerated Acetobacter cultures. This microcarrier-enhanced cellulose synthesis could be the result of the formation of microenvironments with locally lowered dissolved oxygen levels because of the attachment of Acetobacter cells as a biofilm on the particles. As such, less glucose is lost as gluconate, saving it for cellulose formation and maintaining the pH profile within the desirable range. We have also developed a UV-mutation and proton enrichment strategy, which allows the selection of A. xylinum mutants, which are highly restricted in (keto)gluconate synthesis and produce cellulose more efficiently, even under oxidative culture conditions. Combining these nutritional, genetic and bioprocess-technological improvements, very high levels of bacterial cellulose have been attained. Further improvements are needed to arrive at an economical fermentation process for mass production of bacterial cellulose.

Study on coloration of Monascus-nata complex using combination of rice flour, tofu solid waste, and rice bran extracts as the medium

Monascus-nata complex was made up from fermented nata which was grown in the medium containing Monascus purpureus fungi, that could be used as coloration of nata. Rice flour usually used as medium to produce pigments by M. purpureus. Tofu solid waste and rice bran could be used to produce pigments although the colour intensity of M. purpureus pigment was lower than rice. The aims of these research were to study colour, pH medium and weight of miselium Monascus-nata complex from the combination of rice flour with tofu solid waste extracts and rice flour with rice bran extracts as the medium. In these research, 5% (b/v) rice flour extracts, combination of rice flour extract : tofu solid waste extract in the ratio of 1:1, 1:2, 1:3 and rice flour : rice bran extracts in the ratio of 1:1, 1:2, 1:3 were used as the medium. Ten nata de coco (1x1x1 cm3) were put in to the extracts of medium (100mL) in bottle, then inoculated with 10% (v/v) starter of M. purpureus containing 1.3x107 cfu/mL and incubated at room temperature on an orbital shaker at 100 rpm for 16 days. Parameters which were measured, i.e. colour intensity, preferable test, pH medium, weight of miselium Monascus-nata complex. Data were analyzed using analysis of variant and followed by DMRT in 5% significations except preferable test which were analyzed using hedonic test. Combination of rice flour extract : tofu solid waste extracts in the ratio of 1:1 could be used to replace rice flour extracts on the making of Monascus-nata complex. Orange colour intensity from rice flour extract : tofu solid waste extracts in the ratio of 1:1 was higher than from rice flour extracts. Orange colour intensity from rice flour extract : tofu solid waste extracts in the ratio of 1:1 and rice flour were 0.156 and 0.123 respectively. Red colour intensity from medium rice flour extract : tofu solid waste extracts in the ratio of 1:1 approach the red colour intensity of rice flour. Red colour intensity from medium rice flour extract : tofu solid waste extracts in the ratio of 1:1 and rice flour extract were 0.088 and 0.145 respectively. All of pH value decreased from 7 to 6.82. Weight of miselium Monascus-nata complex from all medium was average 0.024 g. © 2005 Jurusan Biologi FMIPA UNS SurakartaKey words: Monascus-nata complex, rice flour, tofu solid waste, rice bran