Useful agents against aflatoxin B₁ – antibacterial azomethine and Mn(III) complexes involving L-Threonine, L-Serine, and L-Tyrosine

Figures & data

Figure 1. Structure of Aflatoxin B_1.

Figure 2. Structures and abbreviations of studied amino acid and Mn(III) complexes.

Table I. Analytical data, important IR vibration frequencies (cm^{− 1}), UV-visible spectra values (nm) of all synthesized molecules and ¹H-NMR spectral data of Schiff bases attached L-Threonine, L- Serine and L-Tyrosine.

Abbreviation of compounds (F. Weight; Mp^oC)	Elementel analysis found (calcd.) %			Important FTIR vibration (cm^−1) and UV-GB spectra (nm; cm^2mol^−1)
	C	H	N	υ(OH)	υ(C = O) υ(C = N)	λmax; ε × 10^2
(Ser-Sch)	64.53	4.89	5.42	3306	1634	304 (9.4), 400 (9.5)
259.62; 190	(64.85)	(5.05)	(5.40)		1620	418 (9.7)
Na[Mn(Ser-Sch)2]•3n	52.35	3.92	3.87	3381	–	304 (9.4) 400 (9.5)
646.46; 140	(52.02)	(4.36)	(4.33)		1620	418 (9.7)
(Thr-Sch)	65.93	5.49	5.12	3455	1640	304 (7.6), 402 (7.8)
273.63; 180	(65.93)	(5.49)	(5.12)		1620	420 (7.9)
[Mn(Thr-Sch)2]•4n	51.7	4.49	4.01	3387	–	224 (5.3), 268 (13.8
692.52; 220	(52.03)	(4.95)	(4.04)	3235	1625	295 (17.6), 325 (15.1)
(Tyr-Sch)	71.46	4.29	4.62	3658	1613	407 (7.3)
335.35; 219	(71.63)	(5.11)	(4.18)		1627	306 (5.9), 404 (4.3)
Na[Mn(Tyr-Sch)2]•3n	59.84	3.97	3.52		–	425 (4.4)
692.52; 220	(60.16)	(4.54)	(3.51)		1615	307 (6.5), 351 (3.4)
						406 (3.7), 488 (0.2)

	-OH	-COOH	-CH = N	ArC-H	C-H	CH2
(Ser-Sch)DMSO	14.09	10.92	9.06	6.90–8.05	4.44	4
(Thr-Sch)	14	10.89	9.3	6.93–8.10	4.47	3.99
(Tyr-Sch)DMSO	14.02	9.25	8.75	6.60–7.90	4.7	3.10–3.20

n: -H₂O

Figure 3. Imaging of antimicrobial affectivities of [Mn(Tyr-Sch)₂], (Tyr-Sch) [Mn(Thr-Sch)₂], and against B. abartuss, M. luteus.

Table II. Antimicrobiyal activity of studied compounds (0.25 μg/ml) and standard reagents (diameter of zone inhibition (mm)).

		(Thr-Sch)	(Ser-Sch)	(Thr-Sch)
Microorganisms		Na[Mn(Thr-Sch)2]	Na[Mn(Ser-Sch)2]	Na[Mn(Thr-Sch)2]	control
Gram (+)	L. monocytogenes 4b	11/16	14/11	12/12	–
	B. cereus	12/15	11/16	17/20	–
	S. aureus	-/13	12/12	12/11	–
	S. epidermis	11/14	-/14	12/11	–
	M. luteus	12/13	-/17	12/15	–
Gram (-)	Sh. dys. typ 7	19/19	20/24	17/19	–
	P. putida	12/-	11/20	24/20	–
	S. typhi H	15/19	16/18	13/19	–
	Br. abortus	22/20	20/26	13/18
	E. coli	12/14	16/11	12/13	–
Yeast	C. albicans	17/15	15/20	16/22	–
Pozitif control	S. aureus	P.putida	E.coli	S.typhi H	Br. abortus	C.albicans
K3025	25	14	25	20	–
SXT25	24	18	18	17	–	–
AMP10	30	8	10	11	–	–
AMC30	30	15	14	19	–	–
NYS100	–	–	–	–		20

SXT25, Sulphamethoxazol 25 μg; AMP10, Ampicillin 10 μg; NYS100, Nystatin 100 μg; K30, Kanamycin 30 μg; AMC30, Amoxycillin 30 μg.

Table III. Comparison the effects on the number of MN different concentrations of (Thr-Sch).

	Counted	Sight			Counted	Sight
	of MN	of MN	MN/Cell		of MN	of MN	MN/Cell
Control	1014	38	3.75 ± 0.12^a	Control	1008	43	4.27 ± 0.19^a
AFB1 5 μM	1006	62	6.16 ± 0.15^f	AFB1 5 μM	1004	74	7.37 ± 0.24^e
Mn(Thr-Sch) (40 μM)	1015	45	4.43 ± 0.12^bc	(Thr-Sch (40 μM)	1012	46	4.55 ± 0.16^ab
AFB1(5 μM)+ Mn(Thr -Sch)2(5 μM)	1011	53	5.24 ± 0.12^e	AFB1(5 μM)+ Thr-Sch (5 μM)	1009	66	6.54 ± 0.19^d
AFB1(5 μM)+ Mn(Thr -Sch)2(10 μM)	1016	48	4.72 ± 0.12^d	AFB1(5 μM)+ Thr-Sch (10 μM)	1010	55	5.45 ± 0.19^c
AFB1(5 μM)+ Mn(Thr -Sch)2(20 μM)	1016	43	4.23 ± 0.12^b	AFB1(5 μM)+ Thr-Sch (20 μM)	1009	48	4.76 ± 0.19^b
Control	1020	31	3.04 ± 0.81^a	Control	1010	38	2.48 ± 0.81^a
AFB1 5 μM	1015	63	6.21 ± 0.81^e	AFB1 5 μM	1019	55	5.27 ± 0.81^de
Mn(Ser -Sch)(OAc)(40 μM)	1019	53	5.20 ± 0.81^d	(Ser -Sch (40 μM)	1002	49	3.06 ± 0.81^abc
AFB1(5 μM)+ Mn(Ser-Sch)2(5 μM)	1023	45	4.40 ± 0.81^cd	AFB1(5 μM)+ Ser -Sch (5 μM)	1020	44	4.27 ± 0.81^bd
AFB1(5 μM)+ Mn(Ser-Sch)2(10 μM)	1011	39	4.39 ± 0.81^bc	AFB1(5 μM)+ Ser -Sch (10 μM)	1015	41	3.55 ± 0.81^abc
AFB1(5 μM)+ Mn(Ser-Sch)2(20 μM)	1018	34	3.34 ± 0.81^ab	AFB1(5 μM)+ Ser -Sch (20 μM)	1012	37	2.89 ± 0.81^ab
Control	1006	35	3.48 ± 0.41^a	Control	1012	20	1.98 ± 0.22^a
AFB1 5 μM	1000	69	6.90 ± 0.41^e	AFB1 5 μM	1004	43	4.28 ± 0.22^e
Mn(Tyr-Sch) (40 μM)	1003	51	5.04 ± 0.41^bcd	(Tyr-Sch) (40 μM)	1018	37	3.63 ± 0.22^d
AFB1(5 μM)+ Mn(Tyr -Sch)2(5 μM)	1001	49	4.90 ± 0.41^bc	AFB1(5 μM)+(Tyr-Sch)(5 μM)	1013	31	3.06 ± 0.22^c
AFB1(5 μM)+ Mn(Tyr -Sch)2(10 μM)	1003	41	4.09 ± 0.41^abc	AFB1(5 μM)+ Tyr-Sch (10 μM)	1011	25	2.47 ± 0.22^b
AFB1(5 μM)+ Mn(Tyr -Sch)2(20 μM)	1004	37	3.69 ± 0.41^ab	AFB1(5 μM)+ Tyr-Sch (20 μM)	1016	23	2.26 ± 0.22^a,b

[Mn(Thr-Sch)(OAc), (Ser-Sch), [Mn(Ser-Sch)OAc], (Tyr-Sch), [Mn(Tyr-Sch)(OAc) together with AFB₁ in human peripheral lymphocytes.

^aP < 0.05 compared with control.

^fP < 0.05 compared with AFB1 (5 μM) group.

Figure 4. Some products formed by oxidation of AFB_1.

Figure 5. Hypothesis reduced the effect mechanism of Aflatoxin derivaties.