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1 – 10 of 38Juliana Villasante, Johanan Espinosa-Ramírez, Esther Pérez-Carrillo, Erick Heredia-Olea and MariaPilar Almajano
Solid-state fermentation (SSF) has been highlighted as an alternative to obtain valuable compounds using agro-industrial wastes as a substrate. The present study evaluated the…
Abstract
Purpose
Solid-state fermentation (SSF) has been highlighted as an alternative to obtain valuable compounds using agro-industrial wastes as a substrate. The present study evaluated the impact of extrusion combined with SSF on the production of phenolic compounds and their antioxidant activity using pecan nut shell (PWS) as a substrate.
Design/methodology/approach
PWS and extruded pecan nut shell (PWSE) were fermented for 120 h at 30°C using Aspergillus oryzae (A. oryzae). Samples were withdrawn from incubator at 6 h, 12 h and then every 12 h until 120 h fermentation. PWS and PWSE samples were extracted. The total phenolic content (TPC) and radical scavenging activity (RSA) extracts were characterized from the resulting extracts.
Findings
The use of PWSE yielded higher A. oryzae biomass and at a higher rate after 120 h of fermentation (PWS 75.74% vs PWSE 87.50%). In general, the TPC and the RSA increased with fermentation time. However, the PWSE yielded significantly higher (p < 0.05) TPC and RSA values after SSF in comparison to the nonextruded PWS. Condensed tannins showed different trends depending on the fermented substrate. Overall, results showed that the extrusion pretreatment joint with the SSF represents a good alternative to raise the phenolic content and antiradical activity of lignocellulosic materials such as PWSs.
Originality/value
This study offers valuable information that may be used by the pecan walnut industry to valorize the shell coproduct as a substrate to produce functional ingredients or fungal enzymes.
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Dawa Dolma Bhutia, Yeka Zhimo, Ramen Kole and Jayanta Saha
The purpose of this paper was to determine the antifungal activities of different solvent extracts of common plants in vitro and in vivo against banana anthracnose fungus…
Abstract
Purpose
The purpose of this paper was to determine the antifungal activities of different solvent extracts of common plants in vitro and in vivo against banana anthracnose fungus Colletotrichum musae (Berk & M.A. Curtis) Arx, and to investigate its effects on the pathogen and identify the bio active component(s).
Design/methodology/approach
Extracts were obtained from leaves, tender shoots, rhizomes, bulbs, seeds and fruits of 42 naturally growing plant species following hot sequential extraction. Preliminary screening of the solvent extracts was done based on the inhibition of radial mycelial growth of C. musae following poison food technique and conidial germination inhibition by cavity slide technique. The selected extracts were assessed for their effect on harvested banana in reducing anthracnose during storage. The active components in the bio-active fractions of plant extract were identified by gas chromatography-mass spectroscopy.
Findings
Methanol extracted a larger quantity of material (between 6.9 and 12.5 per cent) than hexane or chloroform, and all its extracts were active against the test pathogen with mycelial growth inhibition ranging from 13.70 to 88.89 per cent. Zingiber officinale rhizome extract as well as Polyalthia longifolia and Clerodendrum inerme leaf extracts exhibited more than 80 per cent inhibition of mycelial growth. Total inhibition of spore germination of C. musae was recorded in Z. officinale and P. longifolia extracts at 0.3 per cent w/v and 0.5 per cent w/v concentration, respectively, while only 68 per cent spore inhibition was recorded in C. inerme at 0.5 per cent w/v concentration. Of the three plant species, Z. officinale had the best antifungal activity (18.0 per cent disease incidence; 2.2 disease severity scale) when banana fruits were dipped in the extract at a concentration of 0.5 per cent w/v at 5 days of storage in ambient condition (80-82 per cent R.H., 27 ± 1°C). The bio-active compounds in the extract of Z. officinale were identified as alpha-curcumene and zingerone.
Originality/value
Based on the antifungal activity, plant extract of Z. officinale can be used as an effective alternative to chemicals in controlling anthracnose pathogen in harvested banana.
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Daniella Cristine Fialho Lopes, Fernanda Meneghello Delvivo and Marialice Pinto Coelho Silvestre
This paper aims at testing several conditions using activated carbon for removing phenylalanine (Phe) from protein hydrolysates, in order to prepare dietary supplements for…
Abstract
Purpose
This paper aims at testing several conditions using activated carbon for removing phenylalanine (Phe) from protein hydrolysates, in order to prepare dietary supplements for phenylketonurics, based on skim milk.
Design/methodology/approach
Six hydrolysates from skim milk were prepared, using a protease from Aspergillus oryzae (AO), isolated or in association with papain (PA). Some parameters were tested for removing Phe, such as amount of activated carbon, temperature and stirring time. The second derivative spectrophotometry was used to evaluate the efficiency of Phe removal.
Findings
The best condition for removing Phe was achieved using an activated carbon: casein ratio of 118 (in g), a stirring time of 30 min, at a temperature of 25°C, which produced 96 to 99 per cent of Phe removal. Among the hydrolytic conditions employed, the association of AO and PA (1 hour, 1 per cent and 4 hours, 2 per cent, respectively) led to the lowest absolute value for the final Phe concentration (0.060 × 10−4 mg/100 mg of protein).
Original/value
Since we know, there is no formula for PKU on the market based on skim milk hydrolysed proteins. Isolated casein, the main milk protein, is the choice in most cases. This is a factor that may be taken in consideration especially in developing countries, where milk proteins are imported and, consequently, are much more expensive than skim milk.
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Daniella Cristine Fialho Lopes, Fernanda Meneghello Delvivo and Marialice Pinto Coelho Silvestre
The aim of this research is the evaluation of the profile of peptides isolated from skim milk hydrolysates.
Abstract
Purpose
The aim of this research is the evaluation of the profile of peptides isolated from skim milk hydrolysates.
Design/methodology/approach
Five hydrolysates were prepared using a protease from Aspergillus Oryzae (AO) separately or in combination with papain (PA) in different reaction times. The hydrolysates were fractionated by size‐exclusion HPLC and the rapid method of correct fraction area (CFA) was used for quantifying the peptides and free amino acids in the chromatographic fractions. The nutritional quality of hydrolysates is directly related to their di‐ and tripeptide contents, several reports show that the amino acid provided by these peptides are more quickly and completely absorbed than those from intact protein.
Findings
The results showed a nutritional similarity of the isolated action of AO and its combinations with PA, considering the peptide patterns produced, giving rise to 16 percent of di‐ and tripetides. Increasing the reaction time of the two enzymes led to poorer peptide profiles, while no change was achieved when the reaction time of only one enzyme (AO) in the combination was enlarged. Other hydrolytic conditions could be tested in order to improve the peptide profile of skim milk hydrolysates.
Practical implications
The application of this study relates to the possibility of using these hydrolysates for preparing high nutritional formulation for dietetic purposes. The use of a technique allowing the fractionation of peptides according to their size as well as the use of the skim milk as protein source, instead of casein, which is very expensive in the developing countries, represents a novel approach.
Originality/value
Provides an evaluation of the profile of peptides isolated from skim milk hydrolysates.
Zuzana Ciesarová, Kristína Kukurová and Cyntia Benešová
Acrylamide is a processing chemical contaminant arising from naturally occurring food components during heat treatment. The purpose of this paper is to ascertain and confirm the…
Abstract
Purpose
Acrylamide is a processing chemical contaminant arising from naturally occurring food components during heat treatment. The purpose of this paper is to ascertain and confirm the possibility of its reduction by L‐asparaginase enzyme application.
Design/methodology/approach
As acrylamide itself is formed from amino acid L‐asparagine and reducing saccharides via the Maillard reaction, the elimination of one of these precursors by L‐asparaginase enzyme in raw material leads to the suppression of acrylamide content in a final product.
Findings
The application of L‐asparaginase solution in a simulated potato matrix results in 50‐90 per cent reduction of acrylamide content depending on the conditions (enzyme dosage, time and temperature of incubation). No significant differences in the activities of bacterial‐ and fungal‐originated enzymes are observed. The positive effect of L‐asparaginase application on acrylamide content reduction is confirmed also in raw potato mash as well as in dehydrated potato‐wheat semi‐products for making of fried pancakes. No detrimental sensorial or quality impacts on final products are observed.
Research limitations/implications
A described way of an enzyme application is suitable for homogenised mixtures like batter or mash where the efficiency of enzyme activity in the whole mass is guaranteed.
Practical implications
The elimination of acrylamide content in thermally treated foods without an undesirable impact on quality of products could lead to the noticeable diminution of acrylamide intake from foods.
Originality/value
This procedure diversifies the possibility of the enzyme application from a cereal sector to potato‐based foods.
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Language may be a treasured heritage of small comunities, all that is left to bind them together. It is often a matter of national or regional pride, keeping alive a tongue dead…
Abstract
Language may be a treasured heritage of small comunities, all that is left to bind them together. It is often a matter of national or regional pride, keeping alive a tongue dead centuries past everywhere else; in an area of the Grisons forty thousand Swiss speak the Latin Romansch, the tongue spoken by the citizens of ancient Rome, and nowhere else in the world is it heard. There are so‐called official languages; in the councils of Europe, it has always been French, which is the official language of the European Economic Community; this means, of course, that all EEC Directives and in due course, judgments of its courts, will be first delivered in French.
The simplest forms of plant life may prove to be the answer to world food problems and the source of life‐saving nutrients for the hungry nations in the years to come.
The purpose of this paper is to outline the present status of various fermented foods and beverages across the globe and reviews on the microbiology and therapeutic effects of…
Abstract
Purpose
The purpose of this paper is to outline the present status of various fermented foods and beverages across the globe and reviews on the microbiology and therapeutic effects of fermented foods.
Design/methodology/approach
Fermented foods play an important socio-economic role in developing countries as well as making a major contribution to the nutrition requirements of natural populations. These foods have attracted attention all over the world as foods that might promote longevity. The approach is based on observations of online research with respect to fermented foods and their origins, analysis of research papers in journals and systematic research on the microbiology and health benefits of fermented products.
Findings
In general, traditional fermented foods produced with indigenous practices throughout the world are made under primitive conditions, which result in low yield and poor quality. But since, these foods are not only traditional but also functional foods. They are experiencing a burst of popularity as health foods worldwide. The raw materials traditionally used for fermentation are as diverse as: fruits, cereals, vegetables, milk, meat, and fish. It is possible to obtain a large variety of different food products by selecting different raw materials, starter cultures, and fermentation conditions.
Originality/value
The paper offers a holistic view that would guide a reader to identify various fermented products and enlighten them about their therapeutic properties.
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Ji Eun Song, Su Mi Kim and Hye Rim Kim
The purpose of this paper is to improve the dye affinity of natural dye of Terminalia chebula retzius (T. chebula) using the dye substrate of leather.
Abstract
Purpose
The purpose of this paper is to improve the dye affinity of natural dye of Terminalia chebula retzius (T. chebula) using the dye substrate of leather.
Design/methodology/approach
The dyeing conditions such as temperature, concentration of dye, and time are controlled by measuring the dye affinity. The effect of enzymatic post-tanning process on dye affinity is evaluated by using different type of proteases such as flavourzyme, alcalase, and bromelain. The optimum conditions for enzymatic post-tanning process are evaluated depending on different pH, temperature, and concentration of enzyme.
Findings
The highest dye affinity was obtained at 50°C using a dye concentration of 200 percent (owf) for 30 min treatment by measuring of K/S values of dyed leather. Distilled water was proved as a better extraction liquid to improve the dye affinity of T. chebula. The K/S values of dyed leather were enhanced after the enzymatic post-tanning process by flavourzyme. Moreover, the fastness properties against the rubbing and dry cleaning of the dyed leather were improved by the enzymatic post-tanning process.
Originality/value
In this paper, the enzymatic post-tanning process is introduced as the method to improve the dye affinity in natural dyeing using Terminalia chebula retzius (T. chebula) applied to leather. The results of the study could be applied for further natural dyeing of leather using various natural dyes.
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The next month or two behind us and this decade will have passed, to merge in the drab background of the post‐war years, part of the pattern of frustration, failure and fear. The…
Abstract
The next month or two behind us and this decade will have passed, to merge in the drab background of the post‐war years, part of the pattern of frustration, failure and fear. The ‘swinging sixties’ some called it, but to an older and perhaps slightly jaundiced eye, the only swinging seemed to be from one crisis to another, like the monkey swinging from bough to bough in his home among the trees; the ‘swingers’ among men also have their heads in the clouds! In the seemingly endless struggle against inflation since the end of the War, it would be futile to fail to see that the country is in retreat all the time. One can almost hear that shaft of MacLeodian wit christening the approaching decade as the ‘sinking seventies’, but it may not be as bad as all that, and certainly not if the innate good sense and political soundness of the British gives them insight into their perilous plight.