SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 
    92, 93, 94, 95, 96, 97, 100, 101, 102, 
    103, 104, 105, 106, 107, 108, 109, 110, 
    111, 112, 113, 114, 115, 116, 117, 118, 
    119, 120, 121, 122, 123, 124, 125, 126, 
    127, 128, 129, 130, 131, 132, 133, 134, 
    135, 136, 137, 138, 139, 140, 141, 142, 
    143, 144, 145, 146
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00089

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "181.98"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "128.00"
      },
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "ALL",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "rows_examined_per_scan": 254,
        "rows_produced_per_join": 127,
        "filtered": "50.39",
        "cost_info": {
          "read_cost": "28.38",
          "eval_cost": "25.60",
          "prefix_cost": "53.98",
          "data_read_per_join": "2K"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`satishecarter_march_003`.`cscart_product_prices`.`lower_limit` = 1) and (`satishecarter_march_003`.`cscart_product_prices`.`product_id` in (81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146)) and (`satishecarter_march_003`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}

Result

product_id price
81 49.50000000
82 19.99000000
83 19.99000000
84 19.99000000
85 19.99000000
86 359.00000000
87 19.99000000
88 39.99000000
89 19.99000000
90 19.99000000
91 10700.00000000
92 3225.00000000
93 19.99000000
94 59.99000000
95 19.99000000
96 99.99000000
97 14.99000000
100 22.70000000
101 188.88000000
102 295.00000000
103 23.99000000
104 29.95000000
105 169.99000000
106 179.99000000
107 465.00000000
108 12.99000000
109 140.00000000
110 15.99000000
111 6.99000000
112 8.99000000
113 449.99000000
114 14.99000000
115 4595.00000000
116 6.99000000
117 729.99000000
118 30.99000000
119 17.99000000
120 199.99000000
121 17.99000000
122 5695.00000000
123 17.99000000
124 4595.00000000
125 149.99000000
126 129.99000000
127 4779.00000000
128 17.99000000
129 1799.00000000
130 49.95000000
131 1249.00000000
132 269.99000000
133 229.99000000
134 89.99000000
135 0.00000000
136 0.00000000
137 0.00000000
138 0.00000000
139 0.00000000
140 99.95000000
141 99.95000000
142 399.95000000
143 79.95000000
144 99.95000000
145 79.99000000
146 44.99000000