The true experimental method of research using CRD- pre-test-post-test design [13] was used in conducting the study.

In preparing the commercial enzymatic solution, 41.70 ml of commercial enzymatic solution was diluted in 1.25 liters of distilled water based on the product label.

Equal grams of mango and banana peels where mixed and from that mixture, 321 g of waste was taken and mixed with 107 ml molasses and 1 L of water in a 2 L container and then fermented for 3 months for the experimental enzymatic solutions. After the fermentation period, the solution was filtered and analyzed for the corresponding parameters; pH and BOD (biological oxygen demand). After the laboratory analysis dilution was adjusted to pH 7, about 8 ml of the solution was diluted to 1.9 liters distilled water. Same procedure was also applied with the use of fish intestines as a substitute of fruit peels to make enzymatic solution with the dilution of 2 ml solution in 1.2 L of distilled water.

The prepared enzymatic solutions (experimental) made from fruit peels and fish intestines were mixed to determine the optimal mixture that would produce better result in bio-decomposition and odor reduction of organic solid waste. There were 5 formulations prepared: Formulation 1, a mixture of fruit peels (25%) and fish intestines (75%); formulation 2, a mixture of fish intestines (25%) and fruit peels (75%); formulation 3, a mixture of fish intestines (50%) and fruit peels (50%); formulation 4, an enzymatic solution composed of fruit peels (100%); formulation 5, an enzymatic solution composed of fish intestines (100%).

The amount of carbon dioxide evolved was determined by gravimetric analysis. From the air compressor, a rubber hose was connected to the carbon dioxide trap which contains soda lime to remove the carbon dioxide from the continuous flow of air (Figure 1). A humidifier was used to give enough moisture responsible for the degradation of organic waste. The suction flask/pet bottle that contains water was connected to the 1L suction flask/pet bottle containing 200g of organic waste and then connected to the dehumidifying trap which contains silica gel to remove the air moisture before going to the carbon dioxide absorbing column to avoid the increased in weight of carbon dioxide trap by moisture increase. The dehumidifying trap was connected to the CO₂ absorbing column that contains 80 ml of soda lime and soda talc mixture. This served as the absorbent of the carbon dioxide released by the bottle containing organic waste. The CO₂ absorbing columns were weighed every 24 hours of aeration, the air flow was set to 14 L/hour [14] .

The mass of the evaporating dish was recorded, followed by the grinding of the test specimen using a laboratory blender. The specimen was added to the evaporating dish and weighted. After recording the mass of the evaporating dish with the test specimen, it was then oven-dried uncovered for at least 6 h at 250˚C until there was no change in mass of the sample in excess of 1 hour. The test specimen was removed at the oven and placed in a desiccator for 5 minutes taking down the mass of the oven-dried test specimen. The percentage weight loss was calculated by subtracting the initial weight initial weight from the final dry weight taken from the moisture content determination result over initial weight multiplied by 100 percent.

During the test, the 20 panelists sniffed the prepared samples starting from the sample (a) to sample (g) absorbed via cotton balls. The arrangement was not revealed to the panelist to avoid bias. The panelists were ask to rate the samples based on the odor intensity referencing scale standard practice (Table 1). The result from the survey test was tallied to determine the difference of the odor intensity of the different samples [15] .

Fish intestines contain enzymes that facilitate digestion, absorption and assimilation of molecules like proteins and lipids [18] [19] [20] [21] . Thus it can degrade organic waste and transform it into carbon dioxide and water. Organic waste that contains dried leaves was enclosed in plant cell walls that make it hard to degrade causing long time degradation. Fruit peels contain plant cell wall degrading enzymes that aid in the degradation process. Fruit peels usually contain xylanase, polygalacturonase, cellulase and α-amylase [22] [23] [24] [25] . In this study, amount of carbon dioxide evolved per day was determined for the different enzyme solutions formulated. As shown in Figure 2, the formulation 3 (F3) (50% fruit peels and 50% fish intestines) has the highest increased amount of evolved CO₂ per day with about 1.96 g in 7 days and reached its peak (0.5 g) on day 2. However, on day 5 it falls gradually into 0.4 g and 0.26 g at day 7, respectively. It can also be noted that among the developed FES, F3 reached the greatest amount of CO₂ evolved within the least number of elapsed time.

The organic waste sample applied with F3 (50% fruit peels, 50% fish intestines) has the greatest decreased in weight from day 0 to day 7 as shown in Figure 3. Since F3 yielded the highest amount of CO₂ within the least number of days and the one with the greatest decrease in weight throughout the treatment, it was considered as the best formulation. Thus, the biodegradation efficiency of F3 was compared with that of the commercial enzymatic solution throughout the study.

The treatment of organic waste with F3 resulted to a percentage weight loss of 98.45% in 7 days which was slightly lower than the organic waste sample treated with the commercial enzymatic solution. To support the comparison, statistical analysis was done. The t-test results of total evolved CO₂ and percentage weight loss which indicates that there was no significant difference between the commercial solution and F3 since the computed t-stat value is lower than the critical value. Thus, it can be noted that the biodegradability efficiency of the F3 is comparable with the commercial enzymatic solution in terms of these parameters.

The organic waste sample applied with F3 has a percentage biodegradability of 0.71 with about 505.75 milligram per kilogram per day. Organic wastes on the average has a percent biodegradability of 0.1 - 0.7. This attainment of maximum percent biodegradability of the organic waste sample may be attributed to the treatment made.

The organic waste sample applied with the commercial enzyme solution has a

weighted mean of 2.7 which falls under normal odor. Commercial enzyme solution contains microbes which produces enzyme essential for odor reduction of organic solid waste. On the other hand, F3 has a weighted mean of 2.8 that also falls under the same description as having normal odor. Fruit peels contain enzymes that exhibit inhibition against gram positive and gram negative bacteria [26] [27] [28] [29] . Proliferation of these bacteria is the one responsible for the foul odor of organic waste. Thus, the application of enzymatic solution formulated resulted in normal acceptable odor of organic waste.

The t test results of odor survey indicate that there was no significant difference between the commercial enzymatic solution and F3 since the t stat is lower than the t critical value. Thus, it can be noted that the use of the developed FES comprising of fruit peels and fish intestines was comparable with the commercial enzymatic solution in terms of odor reduction upon degradation of organic waste.