Abdel-Nasser A Zohri

Bio: Abdel-Nasser A Zohri is an academic researcher from Assiut University. The author has contributed to research in topics: Mycobiota & Phyllosphere. The author has an hindex of 2, co-authored 6 publications receiving 86 citations.

Study of soil mycobiota diversity in some new reclaimed areas, Egypt

Abstract: The objective of this survey was to study the diversity of soil fungi, as they play an important role in knowing the soil quality and increase plant productivity. In this work, the chemical composition of soil samples in newly reclaimed localities at Assiut Governorate was studied; mycobiota of those areas were studied reporting some medically important substances produced by three fungal species, namely Aspergillus terreus , Emericella nidulans , and Penicillium chrysogenum , which recorded the highest occurrence all over the year in different studied areas. Soil samples were collected monthly for a whole year from the four selected reclaimed regions at Assiut Governorate, namely Protectorate of Assiut (PR), El-Ghorayeb (GH), El-Wady El-Assiuty (WA), and Petroleum's Farm (PF), and samples were identified using the morphological and microscopic features according to many references and confirmed by Assiut University Mycological Center (AUMC) followed by physiochemical analysis of soil, including measuring total soluble salts and determining the organic matter content, maximum and minimum temperatures, relative humidity, and soil texture. The highest numbers of fungal genera and species were recorded in PR followed by WA and PF, whereas the lowest numbers were recorded in GH. E. nidulans var. acristata and Penicillium funiculosum were isolated with moderate frequency from GH; Aspergillus aegyptiacus and Aspergillus ustus were isolated with moderate frequency from WA; A. aegyptiacus , Eurotium amstelodami , and Fusarium solani were isolated with moderate frequency from PF; Eurotium repens was isolated only from GH; Arthrinium sacchari , Cochliobolus sativus , and Fusarium xylarioides were isolated only from WA; Aspergillus deflectus , Penicillium expansum , and Rhizopus arrhizus were isolated only from PF; Aspergillus niger , Fusarilla indica , Fusarium semitectum , and Trimmatostroma eriodictyonis were isolated only from PR. There are no adequate mycological studies carried out to describe the fungal flora of these areas. Hence, any information on the endemic mycobiota is of great significance.

Biotechnology and Environmental applications of Trichoderma spp.

Abstract: The genus Trichoderma is multicultural soil-borne fungi found in different ecosystems. They are highly successful colonizers of their habitats. Genus Trichoderma is capable of dealing with various environments such as compost, agricultural soils, rhizosphere, and waste material. Therefore, different strains of Trichoderma have been applied in agriculture, bioremediation, waste management, and biotechnology. Many Trichoderma species act as biological control agents and plant growth promoters. Additionally, the genus Trichoderma is a new fungal source for the production of cyclosporin A as well as various hydrolytic enzymes with industrial importance.

Survey of all mycobiota associated with rhizosphere and rhizoplane of different cultivated plants in new reclaimed soil, upper Egypt, and examination of the most common fungal isolates to produce mycotoxins

Abstract: This survey was designed to study the diversity and occurrence of rhizosphere and rhizoplane fungi in the protectorate of Assiut in Egypt, followed by testing the ability of the most common isolated fungal strains to produce mycotoxins. Not many mycological studies have been carried out to describe the fungal flora of this area, which will be of great significance for the endemic mycobiota. Rhizosphere and rhizoplane samples were collected from the protectorate of Assiut, which represents one of the largest distinctive regions of newly reclaimed soil at the Assiut Governorate. The identification of the isolated fungi during our investigation was carried out using the morphological and microscopic features according to many references and confirmed by the Assiut University Mycology Center (AUMC). The most common four fungal species were examined for their capability to produce mycotoxins; in addition, chemical confirmatory tests for mycotoxins were examined.

Construction of a Novel Strictly NADPH- Dependent Pichia stipitis Xylose Reductase by Site-Directed Mutagenesis for Effective Bioethanol Production

Abstract: Xylose reductase (XR) is one of the key enzymes for bio-ethanol production from lignocellulosic biomass. Intercellular redox imbalance, caused by different coenzyme specificity of XR and Xylitol dehydrogenase (XDH), has been thought to be one of the main factors of xylitol excretion. We previously succeeded by protein engineering to improve the ethanol production by reverse the XDH dependence from NAD+ to NADP+. In this study, we employed protein engineering to construct a novel strictly NADPH dependent XR from Pichia stipitis by site directed mutagenesis, in order to effective recycling of cofactor between XR and XDH, which subsequently reduce xylitol accumulation. Double mutant E223G/S271A showed strictly NADPH dependent with 90% of wild-type activity.

Onions—A global benefit to health

Abstract: Onion (Allium cepa L.) is botanically included in the Liliaceae and species are found across a wide range of latitudes and altitudes in Europe, Asia, N. America and Africa. World onion production has increased by at least 25% over the past 10 years with current production being around 44 million tonnes making it the second most important horticultural crop after tomatoes. Because of their storage characteristics and durability for shipping, onions have always been traded more widely than most vegetables. Onions are versatile and are often used as an ingredient in many dishes and are accepted by almost all traditions and cultures. Onion consumption is increasing significantly, particularly in the USA and this is partly because of heavy promotion that links flavour and health. Onions are rich in two chemical groups that have perceived benefits to human health. These are the flavonoids and the alk(en)yl cysteine sulphoxides (ACSOs). Two flavonoid subgroups are found in onion, the anthocyanins, which impart a red/purple colour to some varieties and flavanols such as quercetin and its derivatives responsible for the yellow and brown skins of many other varieties. The ACSOs are the flavour precursors, which, when cleaved by the enzyme alliinase, generate the characteristic odour and taste of onion. The downstream products are a complex mixture of compounds which include thiosulphinates, thiosulphonates, mono-, di- and tri-sulphides. Compounds from onion have been reported to have a range of health benefits which include anticarcinogenic properties, antiplatelet activity, antithrombotic activity, antiasthmatic and antibiotic effects. Here we review the agronomy of the onion crop, the biochemistry of the health compounds and report on recent clinical data obtained using extracts from this species. Where appropriate we have compared the data with that obtained from garlic (Allium sativum L.) for which more information is widely available.

Biological properties of onions and garlic

Abstract: Garlic (Allium sativum) and onion (Allium cepa) are two food ingredients widely used in our gastronomy. Moreover, garlic and onion extracts have been recently reported to be effective in cardiovascular disease, because of their hypocholesterolemic, hypolipidemic, anti-hypertensive, anti-diabetic, antithrombotic and anti-hyperhomocysteinemia effects, and to possess many other biological activities including antimicrobial, antioxidant, anticarcinogenic, antimutagenic, antiasthmatic, immunomodulatory and prebiotic activities. Given the importance of these vegetables and derived supplements as much in feeding as in therapeutic, in the present work, their main biological activities have been reviewed, indicating the compounds responsible for each one of them. In addition, the influence of the processing on the bioactivity and the adverse effects and interactions with different medications have also been considered.

Advances in consolidated bioprocessing systems for bioethanol and butanol production from biomass: a comprehensive review

Abstract: Recently, lignocellulosic biomass as the most abundant renewable resource has been widely considered for bioalcohols production However, the complex structure of lignocelluloses requires a multi-step process which is costly and time consuming Although, several bioprocessing approaches have been developed for pretreatment, saccharification and fermentation, bioalcohols production from lignocelluloses is still limited because of the economic infeasibility of these technologies This cost constraint could be overcome by designing and constructing robust cellulolytic and bioalcohols producing microbes and by using them in a consolidated bioprocessing (CBP) system This paper comprehensively reviews potentials, recent advances and challenges faced in CBP systems for efficient bioalcohols (ethanol and butanol) production from lignocellulosic and starchy biomass The CBP strategies include using native single strains with cellulytic and alcohol production activities, microbial co-cultures containing both cellulytic and ethanologenic microorganisms, and genetic engineering of cellulytic microorganisms to be alcohol-producing or alcohol producing microorganisms to be cellulytic Moreover, high-throughput techniques, such as metagenomics, metatranscriptomics, next generation sequencing and synthetic biology developed to explore novel microorganisms and powerful enzymes with high activity, thermostability and pH stability are also discussed Currently, the CBP technology is in its infant stage, and ideal microorganisms and/or conditions at industrial scale are yet to be introduced So, it is essential to bring into attention all barriers faced and take advantage of all the experiences gained to achieve a high-yield and low-cost CBP process