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In the last years, increasing the population growth followed by an acceleration of the industrial process costs the quality of our ecosystem. Large waste quantities of industrial activities deposit risk concentrations of toxic materials like heavy metals. Heavy metal pollution has been distinguished as serious contaminants with worldwide risk since the industrial modern revolution. Environment depositions of these contaminants intimidate all the biological life forms for its high toxic characteristics. Chemical, physical, and mechanical strategies proved its low efficiency for its high energy needs, high costs, and even leave other secondary wastes to pass through the environment that raising another contaminant issue. Bioremediation through biological scavenging of heavy metals by microorganisms offers simple, low costs, low energy, and eco-friendly strategy for heavy metal elimination. Microorganisms developed …
Kojic acid is a remarkable secondary metabolite of Aspergillus with various hot spot applications in the field of medicine, cosmetics, food, agriculture, and chemistry field. However the needs of stable large production with safe cultures still need continuous searching. Microbial kojic acid concentrated highly on Aspergillus species especially Aspergillus flavus group. Ten isolates of A. flavus and A. oryzae isolated from various Egyptian sources were producible of KA in range 0.091 ±0.01 to 66.81 ±0.95 g/l. Aspergillus oryzae (no. 4) that give maximum production was selected as non-toxinogenic safe isolate for optimizing the production by five levels CCD design of RSM. Maximum value of kojic acid with 108.4% increasing was 139.24 g/L (predicted 135.8 g/L) using glucose (+ 1; 200 g/l), yeast extract (+ 1; 6 g/l), KH 2 PO 4,(+ 1; 1.5 g/l) and MgSO 4. 7H 2 O (+ 1; 1 g/l) through run (24). Model significance and validity tested by R 2 values of KA was 0.987, DM 0.989 and CS 0.9831 and calculated with Derringer’ s desirability function as 0.937. Optimized kojic acid showed stability against different range of heat stress from 40ÂC to 100ÂC during five continuous hours which may attribute that microbial product usually more stable than synthetic ones by attaching it with other active groups that guaranty more stability under stress conditions. Aspergillus oryzae (Ao-4) represents promising safe isolate for industrial kojic acid production with highly product stability using this significant valid experimental design.
Legumes represent one of the most valuable crops all over the world because of their high content of protein, carbohydrates, fibers and minerals. Legumes significantly affect animal and human health along with soil fertility enhancement. Despite large areas under legume cultivation, the per year legume produces are insufficient due to crop losses induced by several biotic and abiotic stress factors. Abiotic stress factors include numerous environmental parameters like temperature, soil compaction, soil contamination, chilling, frost, drought, humidity, and soil water content. Biotic stress factors involve parasites like nematodes, weeds, insects, viruses, bacteria, and fungi. Fungal plant pathogens are considered one of the major reasons of legume crop losses because of their high spreading instances and aggressive infection via seeds or entire plant body. Fungal diseases can even lead to 100% legume yield
Soils are rich with various precious fungi that produce significant metabolites which could solve many medical issues of human life. Kojic acid represents a significant medical metabolite produced by fungi and used as anti-browning, anti-cancer, and anti-diabetic agent in medical products. In this study, a total of 31 species plus 3 varieties belonging to 14 fungal genera were recovered as rhizospheric fungi from the roots area of 30 samples of 27 different plants. The most common isolated genus was Aspergillus however; the most common isolated species were Aspergillus parasiticus, and A. flavus. Fifty two fungal isolates were tested for their ability to produce kojic acid, only 25 fungal isolates have the ability to produce kojic acid with various degrees and 27 isolates couldn’t produce it. Aspergillus flavus var. columnaris Af-19, A. parasiticus Ap-48, A. flavus var. columnaris Af-7, A. flavus Af-52, and A. flavus Af-40 were the high producers of kojic acid giving (g/l) 42.68, 39.96, 39.85, 39.79, and 38.92 kojic acid, respectively. The percent of kojic acid yields based on consumed sugar by these five fungal isolates were 48.60, 44.84, 43.52, 45.00 and 43.62%, respectively. From the obtained data, it could be assumed that rhizospheric fungi represent a promising producers of kojic acid as significant fungal metabolite.
Tensamples of different types of cheese were collected from local markets in Assiut city. The samples included (four soft cheese, three Ras cheese and three Roquefort cheese). All samples were collected and kept under refrigeration condition (5 – 7 ºC).Czapek's dextrose agar medium used for isolation and identification the mycoflora of them. The results observed that nine species belonging to the genera Aspergillus, Penicillium, Alternaria, Eurotium and Rhizopus were recovered and identified. Aspergillus was the most predominant and represented by four species namely A. flavus, A. niger, A. paraciticus, and A. fumigatus. Euotium represented by two species namely E. repens and E. chevalieri. Aspergillus niger found in the four types of cheese. This research aimed to determine the chemical and microbiological quality of some types of cheese including detection and identification of fungi.
Because of their negative effects on the environment, humans, and other organisms, chemical pesticides have been prohibited in many countries. Alternative microbial management is easy-to-implement, effective, and safe for humans and the environment. Fungus-based bio-pesticide products like kojic acid could commercialize as effective alternative chemical pesticides. Aspergillus oryzae ASU44 (OL314732) was isolated from hollyhock rhizosphere and identified using 18S rRNA gene sequencing. The strain showed high ability of kojic acid production especially after optimizing the production using 41-run Box-Behnken statistical design. Maximum kojic acid production was 46.53 g/l (predicted values 46.62 g/l) obtained in run number (23) using Glucose (150, g/l), Yeast extract (5 g/l), KH2PO4 (3 g/l), MgSO4.7H2O (0.5 g/l) and pH (3). The design was effective to applied with coefficient (R2) 0.988, 0.986 (adjusted R2 0.975, 0.972) for kojic acid (g/l) and dry fungal mass formation (g/l). The pathogenicity of the fungus and their kojic acid in addition to standard synthetic kojic acid was investigated to the cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae). All treatments had a considerable impact on aphid mortality. The mortality rate was relative to the duration of exposure and the quantities of bio-pesticides agents. However, data revealed that as concentrations increased, the lethal time values decreased. Aspergillus oryzae ASU44 and its extract containing kojic acid were found effective against A. gossypii. As a result, this research suggests that these agents could be effective in aphid cotton management.
COVID-19 pandemic is a major worldwide health disaster
firstly reported in December 2019. The Food and Drug
Administration (FDA) has offered the public hope of
halting it, authorizing vaccinations for emergency use with
more than 85% efficacy against serious acute respiratory
syndrome (SARS-CoV-2). Recent outbreaks of SARS-CoV-2
variations including spike-protein mutations, the key
vaccines viral target for immune response, have prompted
a thorough investigation into the vaccine's long-term
effectiveness. Consequently, this review assayed the
details on SARS-CoV-2 infection mechanism and how to
control the infection by different types of SARS-CoV-2
vaccines, and their effectiveness against other mutant
strains. Additionally, the review summarized the different
complaints which have been recorded after vaccination. In
conclusion, these negative effects must be constantly
weighed against the predicted advantages in terms of
disease prevention. Although COVID-19 vaccination is
recommended for everyone aged 5 years and older, SARS-
CoV-2 is high likely to continue to be a pandemic
infectious as a result of the broadcasting of variants of th