As per section 68 of income tax Act, “Where any sum is found credited in the books of an assessee maintained for any previous year, and the assessee offers no explanation about the nature and source thereof or the explanation offered by him is not (in the opinion of the AO) satisfactory, the sum so credited may be charged to income- tax as the income of the assessee of that previous year.”
In your question, the sum credited is unsecured cash loan from 50 different persons. Hence this sum may not be taxable under section 68 of income tax act, the above sum a actually a loan amount and also reflected in the books of person giving such loan. Assessee may provide necessary documentation and explanation to the income tax department so that the transaction is not covered under section 68 of income tax act. 
Please further note that under section 269SS, no person is allowed to accept cash loan of Rs. 20000 or more.
under section 269T, no person is allowed to repay loan in cash for rs. 20000 or more.
Violation of above section is subject to penalty of 100% of loan amount.
Section 269 of the Income Tax Act states that no person/ individual must receive in cash an amount of INR 2 lakhs or more in total from another person/ individual in a day. 
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