الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
In this work, an investigation was performed to study the biological activities of some endophytes. Endophytes are considered the chemical synthesizers within plants and some of these compounds have been used for new drug discovery. Recent reports showed the ability of some microorganisms that resides plants named, endophytes to produce these compounds similarly as were produced by the host plant.
In this study, some endophytic fungi and bacteria were isolated from different plant parts (roots, stems, leaves, and flowers) of Catharanthus roseus (Winka) plants with violet and white flowers, grown in areas in Egypt and Libya. Endophytic isolates underwent cultivation, alkaloid extraction by ethyl acetate, and screening for potential production for Vinblastine. The most potential vinblastine producers were examined morphological and identified molecularly as Aspergillus nidulans OR687485, Talaromyces verruculosusOR755888, Brevibacillus borstelensis OR770212, and Planococcus maitriensis OR770212.
Additionally, Aspergillus nidulans OR687485, fungal strain recovered from flowers, violet Catharanthus roseus, grown in Egypt. For cytotoxic activity against cancer cells in a concentration-dependent and time-dependent manner. The ethyl acetate extract of A. nidulans strain showed the best anticancer activity towards MCF-7 Breast Adenocarcinoma cell line with the lowest recorded IC50 value of (3.76 µg/ml). Moreover, data of the DPPH assay illustrates that the ethyl acetate crude extract of Aspergillus nidulans OR687485, exhibited the antioxidant activity and the recorded IC50 value was found to be 368.7±1.82µg/ml.
Furthermore, antimicrobial was found in the ethyl acetate crude extract of Aspergillus nidulans OR687485 was able to inhibit the growth all tested pathogenic organisms, Gram negative bacteria (E. coli ATCC® 25922, and Shigella sonnei ATCC®29930), and effective and able to inhibit the growth both Gram positive bacteria (S. aureus ATCC® 6538 and B. subtilis ATCC® 6633). Moreover, ethyl acetate crud extracts of Aspergillus nidulans, were effective against Candida albicans ATCC® 10231. It is the first time to report that, cytopathic effect inhibition assay displayed reasonable potentiality of ethyl acetate crude extract of A. nidulans in controlling the Coronavirus 229E. The crud extract of Aspergillus nidulans showed low antiviral activity against 229E (low pathogenic corona virus) with selective indices estimated = CC50/estimated IC50 = 1.75.
The present study showed that, Brevibacillus borstelensis OR770212, bacterial strain recovered from the leaves of Catharanthus roseus plant with violet flowers, grown in Egypt. The ethyl acetate extract of the bacterial B. borstelensis strain showed the best anticancer activity towards A-549Lung Cancer cell line with the lowest recorded IC50 value of 7.08 µg/ml. While, Planococcus maitriensis OR770213, bacterial strain recovered from violet flowers of Catharanthus roseus plant grown in Libya. Ethyl acetate crude extract of Planococcus maitriensis OR770213 showed the moderate anticancer activity towards MCF-7: Breast Adenocarcinoma cell line and showed IC50 at 31.04 µg/ml. On the other the ethyl acetate crude extracts of the two studied endophytic bacterial strains, Planococcus maitriensis and Brevibacillus borstelensis showed no antioxidant and antimicrobial activities against all tested pathogenic strains.
In the current study, Talaromyces verruculosus OR755888, fungal strain recovered from root of Catharanthus roseus plant with violet flowers grown in Libya. Ethyl acetate crude extract of T. verruculosus OR755888 showed the moderate anticancer activity towards MCF-7: Breast Adenocarcinoma cell line and t showed IC50 value of 62.57 µg/ml. additionally, data of the DPPH assay illustrates that the ethyl acetate crude extract of T. verruculosus OR755888, exhibited the antioxidant activity and recorded IC50 value was found to be 277.9± 2.63 µg/ml. As antimicrobial activity, ethyl acetate crude extract of T. verruculosu was stronger effective against all tested pathogenic organisms of except Shigella sonnei ATCC®29930. Compared to the extract of A. nidulans, the extract of T. verruculosus is more efficient as an antimicrobial agent recording higher zones of inhibition towards the tested pathogens.
Additionally, as the bast productivity of vinblastine were in the ethyl acetate crude extract Aspergillus nidulans OR687485, and ethyl acetate crude extract Planococcus maitriensis OR770213, were optimized using full factional design. Response surface methodology applied in this study was competent in optimizing the vinblastine production by A. nidulans AUMC15307. Since, unprecedented high yield of vinblastine, 130.53 mg. L-1 could be successfully attained under the recommended optimum values of the tested variables under the employed BBD. On the other hand, the employed CCD was efficient in maximizing the Planococcus maitriensis OR770213 vinblastine to reach 48.747 mg.L-1 under the recommended optimum values of the tested variables. The production of vinblastine was found to reach 130.53 mg. L-1 and 48.747 mg. L-1 suggesting a promising alternative way for fungal and bacterial vinblastine production in a large scale.
Concerning the results of this study, ethyl acetate crude extracts of endophytic fungal strains A. nidulans OR687485 and T. verruculosu OR755888 which carry the bioactive constituents may responsible for the anticancer, antioxidant, and antimicrobial activities. In this study, a number of 17 constituents were detected by GC-MS analysis in the ethyl acetate crude extract of Aspergillus nidulans, and the major constituents were; Heptadecene-(8)-carbonic acid (34.36%), 10-Methoxy-nb alpha methyl corynantheol (32.74%), Triethyl phosphate (10.97%), and Butyl-2-ethylhexyl phthalate (4.23%). While,15 constituents were detected by GC-MS analysis in the ethyl acetate crude extract of Talaromyces verruculosus. The major constituents have been detected in T. verruculosus crude extract were; Butyl-2-ethylhexyl phthalate (52.99 %), Heptadecene-(8)-carbonic acid (21.69%), Triethyl phosphate (4.45 %), and Benzoic acid, 4-[(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)-NNO-azoxy]-, methyl ester (2.72%).
This study proved the potential biological activities of endophytic fungal and bacterial strains. Endophytic microorganisms are an unlimited source of new metabolites, and the crude extracts from these microorganisms may be a promising alternative since its bioactive compounds can be produced on an industrial scale, thus contributing to both a reduction in cost of the final product and the preservation of plant species.
Recommendation
Based on the results of this study, a recommendation can be given to use the alkaloid extracts of Aspergillus nidulans, Brevibacillus borstelensis, Talaromyces verruculosus, and Planococcus maitriensis as promising and attractive sources for developing a cost-effective and more productive Vinblastine source compared to plant.
The advantage of production of vinblastine by endophytes rather than plants, could be the overcoming of the problem of the seasonal availability of the plant. Moreover, strains improvement of new, safe, and inexpensive drugs of plant origin that exhibit anticancer, antioxidant, and antimicrobial agents to minimize the side effects from using the chemical synthetic antibiotic or chemical preservatives.
Additionally, further studies need to be done to compare the efficiency of vinblastine produced by plants vs that produced by endophytes, and also compare bioactive compounds as; antioxidant, antibacterial, antiviral, antifungal, antitumor, antiparasitic, and insecticidal, produced by plants vs those produced by endophytes.