CONSOLIDATED STATEMENTS OF SHAREHOLDERS` EQUITY - USD ($)	Series A Preferred Stock [Member] 5% Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Subscriptions Receivable [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balances at May. 31, 2018		$ 711,040	$ 20,843,550	$ (9,062)	$ (26,136)	$ (17,193,618)	$ 4,325,774
Balances (in Shares) at May. 31, 2018		8,888,011
Exercise of stock options		$ 13,080	108,710				121,790
Exercise of stock options (in Shares)		163,500
Net proceeds from ATM		$ 50,053	1,726,522				1,776,575
Net proceeds from ATM (in Shares)		625,677
Stock subscription receivable				$ 9,062			9,062
Foreign currency translation					(10,395)		(10,395)
Compensation expense in connection with options granted			151,224				151,224
Net loss						(2,393,060)	(2,393,060)
Balances at May. 31, 2019		$ 774,173	22,830,006		(36,531)	(19,586,678)	3,980,970
Balances (in Shares) at May. 31, 2019		9,677,188
Exercise of stock options		$ 11,037	212,497				223,534
Exercise of stock options (in Shares)		137,958
Net proceeds from ATM		$ 133,995	10,098,862				10,232,857
Net proceeds from ATM (in Shares)		1,674,943
Issuance of preferred stock	$ 45,714		1,871,872				1,917,586
Issuance of preferred stock (in Shares)	571,429
Foreign currency translation					(3,310)		(3,310)
Conversion of preferred to common stock	$ (20,000)	$ 20,000
Conversion of preferred to common stock (in Shares)	(250,000)	250,000
Compensation expense in connection with options granted			200,470				200,470
Net loss						(2,339,054)	(2,339,054)
Balances at May. 31, 2020	$ 25,714	$ 939,205	$ 35,213,707		$ (39,841)	$ (21,925,732)	$ 14,213,053
Balances (in Shares) at May. 31, 2020	321,429	11,740,089