الفهرس 
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Abstract
The biomass production from Leucaena leucocephala (Lam.) de Wit (family Fabaceae)
is a valuable source for chemical biorefinery. The bioactive molecules from the methanol
extracts (MES) from various parts of L. leucocephala grown in Egypt were evaluated.
The antibacterial activity against the growth of Erwinia amylovora, Agrobacterium
tumefaciens, and Staphylococcus aureus was determined by the inhibition zones (IZs)
and the minimum inhibitory concentrations (MICs). The antifungal activity against the
growth of Rhizoctonia solani, Fusarium solani, and Alternaria solani was recorded by
measuring the fungal growth inhibition (FGI %) and MICs. The phytochemical
compounds in the MEs were identified by HPLC-DAD, where the higher compounds
identified (mg/kg ME) in seeds were benzoic acid (1520.44), myricetin (848.73), and
rosmarinic acid (792.46); in roots, were benzoic acid (554.04), naringenin (419.99), and
myricetin (205.51); in leaves were rosmarinic acid (4768.16), resveratrol (2983.99),
quercetin (2052.43), myricetin (1432.63), and naringenin (1182.39); in branches, were
rosmarinic acid (2230.26), resveratrol (1605.3), o-coumaric acid (691.16), and myricetin
(681.93); in fruits were rosmarinic acid (431.43) and resveratrol (261.07); in stem-wood,
were ellagic acid (1319.75), p-coumaric acid (1051.59), and ferulic acid (512.45); and in
stem-bark, were resveratrol (1079.01), benzoic acid (1071.11), and catechol (305.51).
The MEs at the concentration of 4000 mg/L from stem-wood, leaves, and stem-bark, the
higher I1Zs against the growth of E. amylovora, A. tumefaciens, and S. aureus with
values of 4.06 cm, 2.5 cm, and 2.63 cm, respectively, were found. The range of MICs
values of MEs was 75-500 mg/L, 75-125 mg/L, and 75-125 mg/L, against the growth of
A. tumefaciens, E. amylovora, and S. aureus, respectively. MEs prepared from seeds,
fruits (pod), and stem-bark at 4000 mg/L showed the higher FGI (100%) against the
growth of A. solani; MEs from seeds and branches observed the higher FGI values of
63.83% and 63.6%, respectively, against the growth of F. solani, and all MEs showed
potent antifungal activity (FGI 100%) against R. solani except for leaf ME (88.06%).
MICs were in the range of 250-500, 250-500, and 500-1000 mg/L against A. solani, F.
solani, and R. solani, respectively. At 500 mg/L, the roots ME showed the highest total
antioxidant activity (94.30%) compared to vitamin C (VC) (98.30%) at 100 mg/L. The
EC50 values of the MEs from seeds, fruits, stem-bark, branches, stem-wood, leaves,
and roots were 424.24 mg/L, 131.40 mg/L, 341.78 mg/L, 380.50 mg/L, 153.59 mg/L,
153.59 mg/L, and 129.89 mg/L compared with VC (6.88 mg/L). In conclusion, the
botanical parts of L. leucocephala have several bioactive compounds, which can act as
promising antimicrobial and antioxidant properties.