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Volume 13, Issue 2, 2024
Online ISSN: 2182-1054
Volume 13 , Issue 2, (2024)
Published: 18.10.2024.
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Contents
18.04.2020.
Original scientific paper
Zizyphus lotus (L.) extracts as prebiotics in the aggregation and adhesion of probiotic and inhibition of pathologic bacteria from patients with colorectal cancer
The mucosal surfaces of the intestinal tract harbor a complex microbiota. Bacteria enter in contact with intestinal cells and bestow important nutritional, metabolic and protective functions which benefit the host. Various factors are able to alter the balances between different intestinal bacteria. Dysbiosis has been described in various pathologies and metabolic diseases in humans, such as cancer. Colorectal cancer pathology can benefit from gut microbial imbalance. Its overgrowth may lead to acute symptoms. An alternative strategy to restore this balance is the use of plant extracts which exhibit a prebiotic activity by stimulating of probiotic bacteria and antimicrobial activity against pathogenic bacteria colonization. The present study aims to evaluate the in vitro antioxidant and antibacterial activity of phenolic extracts (Aqueous extract "AE" and Methanolic extract "ME" ) from Zizyphus lotus. It aims also to investigate the effect of this extract as a prebiotic on the aggregation of probiotic and inhibitory effects of pathogenic bacteria isolated from faeces of patients with colorectal cancer. Phytochemical analysis of different extracts from Zizyphus lotus by HPLC showed that all are rich in phenolic compounds (225.40 mgAGE/gDW for AE and 63.04 mgAGE/gDW for ME extracts). Moreover, all extracts showed an important antioxidant activity (227 µg/ml for AE and 195 µg/ml for ME). These extracts also exhibited a significant prebiotic effect and antibacterial activity. Characterization of the in vitro effect of the aqueous extract showed that the percentage of autoaggregation and adhesion of probiotic and inhibitory effects of pathogenic bacteria increased in the presence of aqueous extracts.
Sara Ouldchikh, Aicha TirTouil, Boumédiene Meddah
18.04.2020.
Original scientific paper
Effect of olive pulp enrichment on physicochemical and antioxidant properties of wheat bread
Black and green olive pulp was added to wheat bread formulation at different levels (5, 10, 15%) with the aim to improve its nutritional value by enhancing the phenolic content and antioxidant capacity. Additionally, the effects of the fortification with olive pulp on the physical characteristics, staling rate and overall consumer acceptability of the formulated breads were explored. Both olive pulps exhibited significantly higher antioxidant activity than refined wheat flour. Baking imparted an impressive increase in TPC, TFC and antioxidant activity of breads as revealed by comparison of experimental with theoretical values but returned significant differences only in the case of TPC when a two-tailed t-test for paired data was applied. Texture measurements showed a substantial increase in hardness with storage along with decreasing loaf volume and increased density. Hydroxytyrosol was the major phenolic compound of fortified breads followed by tyrosol. Olive pulp could be incorporated in a bread formulation without interfering with the general sensory acceptability.
Anna Marinopoulou, Maria Papageorgiou, Maria Irakli, Dimitrios Gerasopoulos
18.10.2020.
Original scientific paper
Biodegradable film development by nisin Z addition into hydroxypropylmethylcellulose matrix for mozzarella cheese preservation
Currently, improvement of food preservation has been a substantial challenge for industries to increase shelf-life of products and to maintain food quality during storage. These goals are often tied to the sustainable tendency for use of eco-friendly packaging to store these products without loss of the packaging features. Therefore, the aim of this study was to produce biodegradable antimicrobial films by the incorporation of nisin Z peptide under different concentrations (0 %, 5 %, 10 %, 15 % and 20 % wt.) into hydroxypropylmethylcellulose (HPMC) matrices. The active film properties were evaluated in terms of their antimicrobial capacity in vitro, mechanical performance and microscopic characteristics. Hence, active films containing 10 % (wt.) of nisin Z and control films were placed in contact with sliced mozzarella cheese for eight days, and microbiological growth was monitored during storage. Nisin Z’s antimicrobial effects were observed against the Gram-positive microorganisms such as Staphylococcus aureus and Listeria innocua, regardless if the compound was free as a suspension or incorporated into HPMC matrices. However, the expected low action of nisin Z against Gram-negative bacteria, as reported in literature, was not observed since Salmonella enterica Choleraesuis’s growth was inhibited. Moreover, active films with added nisin Z (10 % wt.) were more effective than the control film to inhibit mesophilic microorganisms in mozzarella cheese during 8 days of storage. The mechanical properties of the films were not influenced by nisin Z incorporation, since the addition of the compound enhanced the active function without the loss of mechanical properties required for a good food packaging. These results suggest that biodegradable films produced by nisin Z addition into HPMC matrix are an excellent biomaterial for mozzarella cheese preservation.
Pedro Augusto de Freitas, Rafael R. A. Silva, Taíla V. de Oliveira, Raquel R. A. Soares, Nilda F. F. Soares
18.04.2020.
Original scientific paper
Evaluation of growth and cereulide production by Bacillus cereus isolated from cooked rice
Conditions influencing Bacillus cereus growth and cereulide production, such as temperature and pH, were evaluated at varying incubation periods. The growth and cereulide production at different temperatures and pH values ranging from 10 to 40 ºC and 5.0 to 8.5, respectively showed that the temperature from 20 to 30 ºC and at pH from 6.0 to 7.0 gave the optimum growth and cereulide production by B. cereus SA105. pH below 6.0 resulted in reduced growth and cereulide production. Cereulide production increased along with the incubation period, and maximum cereulide titre (ng/mL) of 1219.1±8.90 was obtained after 6 days of incubation at 30 ºC and pH 6.5 under static conditions. There was no quantifiable toxin at incubation temperatures of 10 and 40 ºC by B. cereus SA105. This work further reveals that B. cereus growth and cereulide production was significantly affected by temperature and pH in relation to the incubation period. Furthermore, the findings of this study will serve as a means for reducing the diversity of emetic toxin-producing B. cereus population in food and food products, thus preventing food poisoning.
Damilola Seyi-Amole, Abiodun A. Onilude, Dasari S. Rani, Prakash M. Halami
18.04.2020.
Original scientific paper
Bacterial diversity, biogenic amines and lipids oxidation in traditional dried anchovy (Encrasicholina punctifer) during ambient storage
This study aimed to elucidate the effect of ambient storage (23±2°C, 68% RH) on the bacterial load and diversity, biogenic amines and lipids oxidation in traditional dried anchovy (E. punctifer) in order to evaluate its safety, quality and stability during 12 weeks of storage. Total aerobic bacteria (TAB), Staphylococcus aureus, Enterobacteriaceae (ENT), histidine decarboxylating bacteria (HDB), lysine decarboxylating bacteria (LDB) and ornithine decarboxylating bacteria (ODB) were enumerated and identified by conventional, VITEK 2 compact and sequencing of 16S rRNA gene methods. Histamine, cadaverine and putrescine contents were determined by high performance liquid chromatography. Lipid oxidation was evaluated by peroxide value (PV). Total aerobic bacteria, S. aureus, ENT, HDB, LDB and ODB initial counts of log10 4.9 ± 0.85, 3.7 ± 0.57, 4.2 ± 0.05, 3.7 ± 0.72, 3.9 ± 0.40 and 4.1 ± 0.24 CFU/g respectively did not significantly change (p > 0.05) during 12 weeks of storage. A high bacterial diversity of 27 species belonging to 20 genera was found, with the dominance of S. aureus, Acinetobacter lwoffii and S. warneri and the first incidence of Psychrobacter celer, Desemzia incerta, Granulicatella elegans and Bhargavaea indica in dried fish. Initial histamine, cadaverine and putrescine contents and PV of 5.2 ± 4.3, 8.5 ± 1.9 and 5.8 ± 0.6 mg/100g and 0.19 ± 0.02 meq/kg respectively did not significantly change (p > 0.05) during 12 weeks of storage. This study found that ambient storage at 23±2°C, 68% RH for 12 weeks did not affect the bacterial load, biogenic amines and lipids, and that the dried anchovy remained microbiologically safe and of good quality.
Ismail Al Bulushi, Nejib Guizani, Mutamed Ayyash, Mohammed Al Za'abi, Aisha Abushelaibi, Hilton C. Deeth, Zahra Al Kharousi, Fathiya Al Hamadani, Salha Al Maskari, Jamila Alkalbani
18.04.2020.
Original scientific paper
Chemical constituents in leaves and aroma products of Nicotiana rustica L. tobacco
Nicotiana rustica L. (Aztec tobacco) is the only Nicotiana species, except common tobacco (N. tabacum L.), which is cultivated for tabacco products. The leaves of N. rustica, however, accumulate various specialized metabolites of potential interest. Therefore, the objective of this study was to evaluate certain classes of metabolites (by HPLC and GC-MS) in the leaves, the essential oil (EO), concrete and resinoid of N. rustica. Three pentacyclic triterpenes were identified in the leaves (by HPLC): betulin (252.78 µg g-1), betulinic (182.53 µg g-1) and oleanolic (69.44 µg g-1) acids. The dominant free phenolic acids in the leaves (by HPLC) were rosmarinic (4257.38 µg g-1) and chlorogenic (1714.40 µg g-1), and conjugated forms of vanillic (3445.71 µg g-1), sinapic (1963.11 µg g-1), and syringic (1784.96 µg g-1). The major flavonoids in the leaves were luteolin (960.44 µg g-1), apigenin (880.66 µg g-1) and hyperosid (780.72 µg g-1). The GS-MS profiling of the EO identified 19 components and the major ones were phytol (43.68 %), solanone (5.54 %), cis-5-butyl-4-methyldihydrofuran-2(3H)-one (5.23 %), dihydro-β-ionone (4.25 %), α-ionene (3.54 %),and β-damascenone (3.03 %). The major volatiles in the concrete were isoamyl alcohol (28.82 %), oxynicotine (9.02 %), phytol (7.80 %), 4-mеthyl-1-penthanol (6.33 %), cotinine (5.55 %) and 3-metyl-3-penthanol (4.09 %). Resinoid composition was dominant by nicotine (39.75 %), phytol (11.23 %), eicosane (4.88 %), diethyl phthalate (4.19 %), dibutyl phthalate (3.48 %) and solanone (3.27 %). Concrete and resinoid showed weak antibacterial activity . These results create grounds for considering N. rustica as a source to obtain aroma or other bioproducts.
Venelina Popova, Tanya A. Ivanova, Albena S. Stoyanova, Violeta V. Nikolova, Margarita H. Docheva, Tzveta H. Hristeva, Stanka T. Damyanova, Nikolay P. Nikolov
18.10.2020.
Original scientific paper
Cooking and functional properties of parboiled milled local rice marketed in the south-east zone of Nigeria
Imported rice is perceived to have better cooking properties than locally grown rice in Nigeria and it has increased its market share while reducing patronage for local rice. Rice in Nigeria has many applications, including consumption as whole cooked grain or dumpling or use as an adjunct in making beverages. Eighteen varieties of parboiled milled local rice and three imported rice varieties, coded Ip1, Ip2 and Ip3, were studied for their cooking and functional properties using standard methods. There was a significant (p<0.05) increase in the dimensions of all the rice varieties when cooked. There was a 25 g increase in the grain weight and an elongation ratio of more than 1.26 in all the rice varieties. Ghesua had the highest cooked grain weight (68.67 g) while Omor-Mas (6.00) and R-Bus (6.00) had the highest volume expansion ratio (VER). The VER was more than 3.00 for all the rice varieties. All the local rice varieties imbibed less water (17.67-25.33 ml) compared to the imported rice varieties (26.00-27.67ml) before they reached their optimum cooking time. The imported rice varieties were of soft gel consistency (89.67-73.50 mm) and intermediate amylose content (20.71-23.14 %) while the local rice varied in amylose and gel consistency. Abakiliki-Mas (27.00 mm) and R-8 (33.67 mm) were of hard gel-consistency, intermediate (21.11 %) and high amylose (27.21 %) content respectively and have not been exploited although they would be appropriate for making canned rice, dry mixes and rice-noodles.
Chinenye Azuka, Iro Nkama, Chinwendu R. Eze, Nahemiah Danbaba, Felix U. Asoiro
18.10.2020.
Original scientific paper
Sensory perception and psychological aspects of eating behavior: factors influencing fat hedonics in Malaysia
Understanding the causes of obesity epidemic requires examination of what contributes to preference of palatable foods. Using a sensorial-consumer approach, this research examined the relationship between the sensation of the hedonic liking of fat with psychological and weight profiles. The study began with preliminary testing of the hedonic ratings of 24 food items (12 low fat (LF), 12 high fat(HF)) and completion of the Three Factor Eating Questionnaire (TFEQ-R18) investigating cognitive restraint, uncontrolled eating and emotional eating aspects. Eight (8) out of the twelve (12) food pairs that had discriminating characteristics were selected, for inclusion in the study, by 347 panellists. Results showed that overweight individuals had significantly lower liking towards LF sensation (4.27±2.13, p= 0.001) but significantly higher liking towards HF sensation (5.26±2.33, p= 0.001), compared to normal BMI individuals who had a significantly higher liking towards LF sensation (5.69±2.35, p= 0.001) but significantly lower liking towards HF sensation (4.17±2.40, p= 0.001). The Pearson product-moment correlation revealed similar trends on the association between liking of fat sensation and eating behaviour regardless of weight statuses. Specifically, cognitive restrainers were found to prefer the LF sensation while HF sensation were more favoured among uncontrolled and emotional eaters. This highlights the importance of investigating the combined effect of psychological aspects of eating behaviour and weight profiles towards liking of fat sensation.
Yun Fei Tan, See Kwong Goh, See Wan Yan
18.10.2020.
Original scientific paper
Food, fish and campylobacteriosis
Food is a necessity of human beings, and the consumption of food is aimed at obtaining energy and nutrients necessary for the growth and proper functioning of the body. However, food can also be a vehicle for various diseases, and the causal agents can have physical, chemical or biological origin with relevance to health due to their incidence, mortality and negative consequences in the population. Bacteria are the main agents of biological origin associated with foodborne diseases. Among these microorganisms are species of the genus Campylobacter, which cause a zoonosis with one of the highest incidences globally, known as Campylobacteriosis. This document provides an overview of foodborne diseases, specifically the causal agents of Campylobacteriosis, including the different measures of control and prevention for this disease in different foods such as poultry, milk, meat, and fish, among others. It also covers the phenomenon of resistance to antimicrobials by these pathogens and the health implications to consumers. The above can generate and maintain safety practices in food production for the protection of public health in different regions around the world.
Alejandro De Jesús Cortés Sánchez
18.10.2020.
Original scientific paper
Modelling relationships between raw milk quality parameters and climatic conditions - the case study of a 3-years survey in Serbia
This work examined the relationships between quality characteristics of raw milk and climatic conditions. Over a period of three years, a total of 5,065 samples were collected encompassing two types of farms. The quality characteristics analysed were titratable acidity (TA), total plate count (TPC) and somatic cells count (SCC). Climatic conditions were evaluated in respect to the outdoor air temperature, pressure, humidity and precipitation. Big farms showed a stronger correlation between TA and climatic conditions as opposed to SCC and climatic conditions. TPC was out of limit in big farms when the outdoor air temperature was higher than 19.8 °C (p<0.05) and during periods with accumulated precipitation over 4.2 mm (p>0.05). Small farms showed a stronger correlation between SCC and climatic conditions as opposed to TA. In these farms, occurrence of acidity out of limit was detected in less than 7.2% of samples. Samples with TA out of limit were observed when air temperature was higher than 18.4 °C (p<0.05) and accumulated precipitation was below 3.1 mm (p>0.05). These results can be used to improve good agricultural practices in respect to climatic conditions and size of farms.
Ilija Djekic, Jelena Miočionović, Marija Bojčevski, Nada Šmigić, Igor Tomašević