β-Glucanase has received great attention in recent years regarding their potential biotechnological applications and antifungal activities. Herein, the specific objectives of the present study were to purify, characterize and immobilize β-glucanase from Aspergillus niger using covalent binding and cross linking techniques. The evaluation of β-glucanase in hydrolysis of different lignocellulosic wastes with subsequent bioethanol production and its capability in biocontrol of pathogenic fungi was investigated. Upon nutritional bioprocessing, β-glucanase production from A. niger EG-RE (MW390925.1) preferred ammonium nitrate and CMC as the best nitrogen and carbon sources, respectively. The soluble enzyme was purified by (NH₄)₂SO₄, DEAE-Cellulose and Sephadex G₂₀₀ with 10.33-fold and specific activity of 379.1 U/mg protein. Tyrosyl, sulfhydryl, tryptophanyl and arginyl were essential residues for enzyme catalysis. The purified β-glucanase was immobilized on carrageenan and chitosan with appreciable yield. However, the cross-linked enzyme exhibited superior activity along with remarkable improved thermostability and operational stability. Remarkably, the application of the above biocatalyst proved to be a promising candidate in liberating the associate lignocellulosic reducing sugars, which was utilized for ethanol production by Saccharomyces cerevisiae. The purified β-glucanase revealed an inhibitory effect on the growth of two tested phytopathogens Fusarium oxysporum and Penicillium digitatum.

Fusarium oxysporum causes wilt disease of tomato crop. Fungal management using fungicides results in several problems in the enviroment. Plant metabolites represent an alternative method since they have minute impact on the enviroment. The present investigation is an attempt to develop eco-friendly management of F. oxysporum using aqueous leaf extract of Ammi majus and Ammi visnaga (Family: Apiaceae). Treating the fungus with aqueous leaf extract from the two species of Ammi plants resulted in the inhibition of the fungal growth. Ammi leaf extracts inhibited the activities of metabolic enzymes including glucose-6-phosphate dehydrogenase (G-6-PD, EC: 1.1.1.49), glutamine synthetase (GS, EC: 6.3.1.2) and nitrate reductase (NR, EC: 1.7.99.4) but increased L-phenylalanine ammonia lyase (PAL, EC: 4.3.1.5) activities of F. oxysporum. Both of the total amino acids and the total soluble protein contents of F. oxysporum were reduced under the same treatment. The leaf extracts inhibited the activities of the enzymes which are involved in pathogenicity including pectinase (EC 3.2.1.15), protease (EC: 3.4.21.14), cellulase (EC: 3.2.1.4) and xylanase (EC: 3.2.1.8). IC50 values for the four enzymes were 93.32, 69.03, 71.27 and 74.93 mg ml-1, respectively. However, IC50 values were 134.22, 106.31, 90.65 and 100.26 mg ml-1 for the four enzymes in the same order under treatment with A. visnaga leaf extract. The total phenols and total flavonoids in leaf extracts from the two Ammi species were determined and they were higher in A. majus than those of A. visnaga. This study suggests efficiency of Ammi leaf extracts in suppression of Fusarium oxysporum pathogenicity.

Rosmarinic acid (RA) was extracted and determined from Ocimum basilicum, Origanum majorana, Salvia officinalis, Rosmarinus officinalis and Thymus vulgaris. R. officinalis expressed the highest content (186.4 mg/DW) followed by O. majorana (140 mg/DW). However, O. basilicum and T. vulgaris and S. officinalis showed 80.7 mg/DW, 66.7 mg/DW, and 50.4 mg/DW of RA, respectively. Treatment of O. majorana seedlings with the various seaweed extract from J. rubens, C. prolifera and C. sinuosa increased RA content with 7.7%, 21.6% and 50% , respectively. RA from O. majorana exhibited appreciable antioxidant activity using DPPH and ABTS compared to ascorbate as standard antioxidant

Tyrosinase (EC 1.14.18.1) was obtained from Aspergillus nidulans (Eidam) G. Winter (AUMC No. 7147). It is an important enzyme in biosynthesis of melanin and hydroxylation L-tyrosine to dihydroxy-phenylalanine and oxidation to dopaquinone. Tyrosinase was purified from Aspergillus nidulans by ammonium sulphate precipitation, DEAE-cellulose and Sephadex G-200 with specific activity of 230.76 units mg/ protein and the molecular weight was 40 kDa. Ethanolic extracts from Morus alba fruits and leaves of Chenopodium album, Rumex dentatus, Eruca sativa and Urtica urens showed an inhibitory effect against tyrosinase activity. The extract from Rumex dentatus leaves expressed the lowest IC50 value (The half-maximal inhibitory concentration) (33.8%), while Urtica urens leaves expressed the highest IC50 value for tyrosinase inhibition (82.6 µg/ mL). The contents of total phenols and flavonoids are investigated in the various plant extracts. Morus alba fruit extract expressed the highest content of phenols (328 mg/ g) and flavonoids (241 mg/ g) compared to the other plant extracts. All plant extracts exhibited appreciable scavenging activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) method. Eruca sativa leaves exhibited the highest scavenging activity of 150.9 μg/ mL with DPPH and 142.4 μg/ mL with ABTS+ .This present article reveals that the potential of leaf extract from Eruca sativa is a hopeful whitening agent of natural source versus skin hyperpigmentation.